/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #ffffff;
    overflow-x: hidden;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid #e5e5e5;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    height: 64px;
}

.nav-logo .logo-text {
    font-size: 24px;
    font-weight: 700;
    color: #1a1a1a;
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-link {
    color: #666;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s ease;
}

.nav-link:hover {
    color: #1a1a1a;
}

/* Navigation Dropdown */
.nav-dropdown {
    position: relative;
}

.dropdown-toggle {
    background: none;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    padding: 0;
}

.dropdown-arrow {
    transition: transform 0.2s ease;
}

.dropdown-toggle:hover .dropdown-arrow {
    transform: translateY(1px);
}

.dropdown-menu {
    position: absolute;
    top: calc(100% + 12px);
    left: 0;
    background: white;
    border-radius: 12px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
    border: 1px solid #e5e5e5;
    padding: 8px;
    min-width: 220px;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
    transform: translateY(-8px);
    z-index: 1001;
}

.dropdown-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu::before {
    content: '';
    position: absolute;
    top: -6px;
    left: 24px;
    width: 12px;
    height: 12px;
    background: white;
    border-left: 1px solid #e5e5e5;
    border-top: 1px solid #e5e5e5;
    transform: rotate(45deg);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    color: #333;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    border-radius: 8px;
    transition: background 0.2s ease, color 0.2s ease;
}

.dropdown-item:hover {
    background: #f5f5f5;
    color: #1a1a1a;
}

.dropdown-item svg {
    flex-shrink: 0;
    opacity: 0.7;
}

.dropdown-item:hover svg {
    opacity: 1;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

/* Hero Section */
.hero {
    background-color: #ffffff;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #1a1a1a;
    padding-top: 64px;
}

.hero-content {
    max-width: 800px;
    padding: 0 24px;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
    color: #1a1a1a;
}

.hero-description {
    font-size: 20px;
    font-weight: 400;
    margin-bottom: 40px;
    color: #666;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Sections */
.auth-section,
.main-section,
.payment-section {
    padding: 80px 0;
    background-color: #fafafa;
}

.payment-section {
    background-color: #ffffff;
    border-top: 1px solid #e5e5e5;
}

/* Problems Section */
.problems-section {
    padding: 80px 0;
    background-color: #ffffff;
}

.problems-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
    flex-wrap: wrap;
    gap: 16px;
}

.problems-title {
    font-size: 32px;
    font-weight: 700;
    color: #1a1a1a;
    margin: 0;
}

.problems-controls {
    display: flex;
    gap: 16px;
    align-items: center;
    flex-wrap: wrap;
}

.problems-filters {
    display: flex;
    gap: 12px;
    align-items: center;
}

.filter-select {
    padding: 8px 12px;
    border: 1px solid #d5d5d5;
    border-radius: 6px;
    background-color: #ffffff;
    font-size: 14px;
    color: #333;
    cursor: pointer;
    transition: border-color 0.2s ease;
}

.filter-select:focus {
    outline: none;
    border-color: #1a1a1a;
}

.problems-table-container {
    background-color: #ffffff;
    border-radius: 8px;
    border: 1px solid #e5e5e5;
    overflow: hidden;
}

.problems-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
    table-layout: fixed;
}

.problems-table thead {
    background-color: #f8f9fa;
    border-bottom: 1px solid #e5e5e5;
}

.problems-table th {
    padding: 12px 16px;
    text-align: left;
    font-weight: 600;
    color: #666;
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.problems-table td {
    padding: 12px 16px;
    border-bottom: 1px solid #f0f0f0;
    vertical-align: middle;
    font-size: 13px;
}

.problems-table tbody tr:hover {
    background-color: #f8f9fa;
}

.problems-table tbody tr:last-child td {
    border-bottom: none;
}

.number-col {
    width: 50px;
    text-align: center;
}

.title-col {
    width: 35%;
    min-width: 200px;
}

.topic-col {
    width: 15%;
    min-width: 100px;
}

.difficulty-col {
    width: 12%;
    min-width: 80px;
}

.views-col {
    width: 10%;
    min-width: 70px;
    text-align: right;
}

.asked-col {
    width: 18%;
    min-width: 120px;
}

.problem-title {
    font-weight: 500;
    color: #1a1a1a;
    text-decoration: none;
    display: flex;
    align-items: center;
    line-height: 1.4;
}

.problem-title:hover {
    color: #0071e3;
}

.premium-icon {
    color: #ffd700;
    font-size: 12px;
}

.topic-tag {
    display: inline-block;
    background-color: #1a1a1a;
    color: #ffffff;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.difficulty-easy {
    color: #22c55e;
    font-weight: 500;
}

.difficulty-medium {
    color: #f59e0b;
    font-weight: 500;
}

.difficulty-hard {
    color: #ef4444;
    font-weight: 500;
}

.views-count {
    color: #666;
    font-size: 12px;
    font-weight: 400;
}

.asked-in {
    display: flex;
    align-items: center;
    gap: 3px;
    flex-wrap: wrap;
}

.company-logo {
    width: 18px;
    height: 18px;
    border-radius: 2px;
    background-color: #f0f0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 8px;
    font-weight: 600;
    color: #666;
}

/* Cards */
.auth-card,
.form-card,
.names-card,
.payment-card {
    background: white;
    border-radius: 18px;
    padding: 40px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    max-width: 500px;
    margin: 0 auto;
}

.payment-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
}

/* Typography */
.auth-title,
.section-title,
.payment-title {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 24px;
    text-align: center;
    color: #1d1d1f;
}

.payment-title {
    color: white;
}

.card-title {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 16px;
    color: #1d1d1f;
}

.payment-description {
    font-size: 17px;
    color: #a1a1a6;
    text-align: center;
    margin-bottom: 32px;
}

/* Forms */
.auth-form,
.name-form {
    margin-bottom: 24px;
}

.form-group {
    margin-bottom: 16px;
}

.form-input {
    width: 100%;
    padding: 16px;
    border: 1px solid #d2d2d7;
    border-radius: 12px;
    font-size: 17px;
    font-family: inherit;
    background-color: #f5f5f7;
    transition: all 0.3s ease;
}

.form-input:focus {
    outline: none;
    border-color: #0071e3;
    background-color: white;
    box-shadow: 0 0 0 4px rgba(0, 113, 227, 0.1);
}

.form-actions {
    display: flex;
    gap: 12px;
    margin-top: 24px;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    min-width: 100px;
}

.btn-primary {
    background-color: #1a1a1a;
    color: white;
}

.btn-primary:hover {
    background-color: #333;
}

.btn-outline {
    background-color: transparent;
    color: #1a1a1a;
    border: 1px solid #d5d5d5;
}

.btn-outline:hover {
    background-color: #f5f5f5;
    border-color: #1a1a1a;
}

.btn-signin {
    background-color: transparent;
    color: #666;
    border: 1px solid #d5d5d5;
    font-size: 14px;
    font-weight: 500;
}

.btn-signin:hover {
    background-color: #f5f5f5;
    color: #1a1a1a;
}

.btn-google {
    background-color: #4285f4;
    color: white;
    width: 100%;
}

.btn-google:hover {
    background-color: #3367d6;
}

.btn-large {
    padding: 16px 32px;
    font-size: 16px;
    min-width: 200px;
}

/* Divider */
.divider {
    text-align: center;
    margin: 24px 0;
    position: relative;
}

.divider::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 1px;
    background-color: #d2d2d7;
}

.divider span {
    background-color: white;
    padding: 0 16px;
    color: #86868b;
    font-size: 14px;
}

/* Section Header */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
    flex-wrap: wrap;
    gap: 16px;
}

/* Content Grid */
.content-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    margin-top: 40px;
}

@media (max-width: 768px) {
    .content-grid {
        grid-template-columns: 1fr;
    }
}

/* Names List */
.names-list {
    list-style: none;
    max-height: 300px;
    overflow-y: auto;
}

.names-list li {
    padding: 12px 16px;
    border-bottom: 1px solid #f5f5f7;
    font-size: 17px;
    color: #1d1d1f;
}

.names-list li:last-child {
    border-bottom: none;
}

/* Response Messages */
.auth-response,
.form-response {
    margin-top: 16px;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 14px;
    text-align: center;
    font-weight: 500;
}

.auth-response {
    color: #1d1d1f;
}

.form-response {
    color: #1d1d1f;
}

/* Error state for auth responses */
.auth-response.error,
.form-response.error {
    background-color: #fee;
    border: 2px solid #ef4444;
    color: #dc2626;
    font-weight: 600;
}

/* Success state for auth responses */
.auth-response.success,
.form-response.success {
    background-color: #f0fdf4;
    border: 2px solid #10b981;
    color: #059669;
    font-weight: 600;
}

/* Forgot Password Styles */
.forgot-password-link {
    text-align: center;
    margin-top: 16px;
}

.forgot-password-link a {
    color: #007dfa;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s ease;
}

.forgot-password-link a:hover {
    color: #0056b3;
    text-decoration: underline;
}

.forgot-password-section {
    margin-top: 24px;
}

.forgot-password-title {
    font-size: 24px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
    text-align: center;
}

.forgot-password-description {
    font-size: 14px;
    color: #666;
    text-align: center;
    margin-bottom: 24px;
    line-height: 1.5;
}

/* Reset Password Styles */
.reset-password-section {
    margin-top: 24px;
}

.reset-password-title {
    font-size: 24px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
    text-align: center;
}

.reset-password-description {
    font-size: 14px;
    color: #666;
    text-align: center;
    margin-bottom: 24px;
    line-height: 1.5;
}

/* Footer */
.footer {
    background-color: #1a1a1a;
    color: #ffffff;
    padding: 60px 0 20px;
    margin-top: 80px;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section {
    display: flex;
    flex-direction: column;
}

.footer-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
    color: #ffffff;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.footer-link {
    color: #cccccc;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s ease;
}

.footer-link:hover {
    color: #ffffff;
}

.footer-bottom {
    border-top: 1px solid #333;
    padding-top: 20px;
    text-align: center;
}

.footer-copyright {
    color: #999;
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-description {
        font-size: 18px;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
        gap: 32px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .auth-card,
    .form-card,
    .names-card,
    .payment-card {
        padding: 24px;
        margin: 0 16px;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-description {
        font-size: 16px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 24px;
    }
}

/* Problem Detail Page Styles */
/* Back to Problems Link at Top */
.back-section-top {
    padding: 24px 0 16px;
    background-color: #ffffff;
}

.back-section-top .back-link {
    color: #666;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    transition: color 0.2s ease;
}

.back-section-top .back-link:hover {
    color: #007dfa;
}

.problem-detail-section {
    padding: 32px 0 80px;
    background-color: #f8f9fa;
    min-height: calc(100vh - 200px);
}

.problem-detail-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    overflow: hidden;
    max-width: 900px;
    margin: 0 auto;
    border: 1px solid #e5e5e5;
}

/* Centered Header Styles */
.problem-detail-header-centered {
    text-align: center;
    padding: 48px 40px 32px;
    border-bottom: 1px solid #e5e5e5;
    background: linear-gradient(180deg, #fafbfc 0%, #ffffff 100%);
}

.problem-meta-centered {
    display: flex;
    gap: 12px;
    justify-content: center;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.problem-title-centered {
    font-size: 32px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 16px;
    line-height: 1.3;
    letter-spacing: -0.02em;
}

.problem-stats-centered {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    color: #666;
    font-size: 14px;
    flex-wrap: wrap;
}

.stats-separator {
    color: #ccc;
    font-weight: 300;
}

.problem-detail-header {
    margin-bottom: 40px;
    max-width: 800px;
}

.problem-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.problem-difficulty {
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.problem-topic {
    background-color: #1a1a1a;
    color: #ffffff;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 500;
}

.premium-badge {
    background-color: #ffd700;
    color: #1a1a1a;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
}

.problem-title {
    font-size: 36px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 16px;
    line-height: 1.2;
    letter-spacing: -0.01em;
}

.problem-stats {
    display: flex;
    align-items: center;
    gap: 16px;
    color: #666;
    font-size: 13px;
    flex-wrap: wrap;
}

.views-count {
    display: flex;
    align-items: center;
    gap: 4px;
}

.asked-in {
    display: flex;
    align-items: center;
    gap: 4px;
}

.problem-content {
    padding: 40px;
}

.section-heading {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 20px;
}

.problem-description {
    background-color: #fafbfc;
    border-radius: 8px;
    padding: 32px;
    margin-bottom: 32px;
    border: 1px solid #e5e5e5;
}

.problem-description h2 {
    font-size: 18px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
}

.problem-description p {
    font-size: 15px;
    line-height: 1.5;
    color: #333;
    margin: 0;
}

/* List styling */
.problem-description ul,
.problem-description ol {
    font-size: 15px;
    line-height: 1.8;
    color: #333;
    margin: 16px 0;
    padding-left: 24px;
}

.problem-description li {
    margin-bottom: 8px;
}

.problem-description ul {
    list-style-type: disc;
}

.problem-description ol {
    list-style-type: decimal;
}

/* MathJax styling */
.problem-description .MathJax {
    font-size: 1em !important;
}

.problem-description .MathJax_Display {
    margin: 1em 0 !important;
}

.problem-description mjx-container {
    overflow-x: auto;
    overflow-y: hidden;
}

.problem-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 32px;
    justify-content: flex-start;
}

.problem-solution {
    background-color: #fafbfc;
    border-radius: 12px;
    padding: 32px;
    margin-top: 32px;
    border: 1px solid #e5e5e5;
    border-left: 4px solid #007dfa;
}

.problem-solution h2 {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.problem-solution h2::before {
    content: "💡";
    font-size: 18px;
}

.solution-content {
    font-size: 15px;
    line-height: 1.6;
    color: #333;
}

.solution-content p {
    margin: 0;
}

.solution-content ul,
.solution-content ol {
    margin: 16px 0;
    padding-left: 24px;
}

.solution-content li {
    margin: 8px 0;
    line-height: 1.5;
}

.solution-content ul {
    list-style-type: disc;
}

.solution-content ol {
    list-style-type: decimal;
}

.solution-content strong {
    font-weight: 600;
    color: #1a1a1a;
}

.solution-content em {
    font-style: italic;
    color: #2c3e50;
}

.solution-content code {
    background-color: #f1f3f4;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.9em;
    color: #d63384;
}

.solution-content u {
    text-decoration: underline;
    text-decoration-color: #007dfa;
}

.back-section {
    padding: 32px 0;
    background-color: #f5f5f7;
    border-top: 1px solid #e5e5e5;
}

/* About Page Styles */
.about-hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.about-hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 24px;
    line-height: 1.2;
}

.about-hero-description {
    font-size: 20px;
    line-height: 1.6;
    max-width: 800px;
    margin: 0 auto;
    opacity: 0.9;
}

.about-mission,
.about-story,
.about-team {
    padding: 80px 0;
    background-color: #ffffff;
}

.about-values {
    padding: 80px 0;
    background-color: #f8f9fa;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-section-title {
    font-size: 36px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 32px;
    line-height: 1.2;
}

.about-section-title.text-center {
    text-align: center;
}

.about-paragraph {
    font-size: 18px;
    line-height: 1.7;
    color: #333;
    margin-bottom: 24px;
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.value-card {
    background: white;
    padding: 32px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    border: 1px solid #e5e5e5;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.value-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.value-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.value-title {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
}

.value-description {
    font-size: 16px;
    line-height: 1.6;
    color: #666;
}

.about-cta {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.cta-content {
    max-width: 600px;
    margin: 0 auto;
}

.cta-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 16px;
    line-height: 1.2;
}

.cta-description {
    font-size: 18px;
    line-height: 1.6;
    margin-bottom: 32px;
    opacity: 0.9;
}

.cta-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.logo-link {
    text-decoration: none;
    color: inherit;
}

.logo-link:hover {
    text-decoration: none;
    color: inherit;
}

.back-link {
    color: #666;
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    transition: color 0.2s ease;
}

.back-link:hover {
    color: #1a1a1a;
}

/* Responsive Design for Problem Detail */
@media (max-width: 768px) {
    .problem-detail-section {
        padding: 80px 0 60px;
    }
    
    .problem-title {
        font-size: 28px;
    }
    
    .problem-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 6px;
    }
    
    .problem-stats {
        flex-direction: column;
        align-items: flex-start;
        gap: 6px;
    }
    
    .problem-description {
        padding: 20px;
    }
    
    .problem-actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .problem-title {
        font-size: 24px;
    }
    
    .problem-description {
        padding: 16px;
    }
    
    .problem-description h2 {
        font-size: 16px;
    }
}

/* Resources Section */
.resources-section {
    padding: 80px 0;
    background-color: #f8f9fa;
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.resource-card {
    background: white;
    border-radius: 12px;
    padding: 32px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.resource-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.resource-icon {
    font-size: 48px;
    margin-bottom: 16px;
    display: block;
}

.resource-title {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
}

.resource-description {
    font-size: 15px;
    color: #666;
    line-height: 1.5;
    margin-bottom: 20px;
}

.resource-link {
    color: #1a1a1a;
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
    transition: color 0.2s ease;
}

.resource-link:hover {
    color: #0071e3;
}

/* Pricing Section */
.pricing-section {
    padding: 80px 0;
    background-color: #ffffff;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.pricing-card {
    background: white;
    border: 2px solid #e5e5e5;
    border-radius: 16px;
    padding: 40px 32px;
    text-align: center;
    position: relative;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.pricing-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
}

.pricing-card-featured {
    border-color: #1a1a1a;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: #1a1a1a;
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.pricing-title {
    font-size: 24px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 16px;
}

.pricing-price {
    font-size: 48px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 32px;
}

.pricing-period {
    font-size: 16px;
    font-weight: 400;
    color: #666;
}

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
    text-align: left;
}

.pricing-features li {
    padding: 8px 0;
    font-size: 15px;
    color: #333;
    display: flex;
    align-items: center;
}

.pricing-features li:before {
    content: '';
    width: 4px;
    height: 4px;
    background: #22c55e;
    border-radius: 50%;
    margin-right: 12px;
}

/* Responsive Design for New Sections */
@media (max-width: 768px) {
    .resources-grid,
    .pricing-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .resource-card,
    .pricing-card {
        padding: 24px;
    }
    
    .pricing-price {
        font-size: 36px;
    }
}

/* Companies Section */
.companies-section {
    padding: 80px 0;
    background-color: #f8f9fa;
    text-align: center;
}

.companies-title {
    font-size: 32px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 48px;
    line-height: 1.3;
}

.highlight {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}

.companies-grid {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 48px;
    flex-wrap: wrap;
    max-width: 1000px;
    margin: 0 auto;
}

.company-logo-large img {
    height: 40px;
    width: auto;
}

/* Testimonials Section */
.testimonials-section {
    padding: 80px 0;
    background-color: #ffffff;
    text-align: center;
}

.testimonials-title {
    font-size: 32px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 48px;
    line-height: 1.3;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.testimonial-card {
    background: white;
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    text-align: left;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.testimonial-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
}

.testimonial-text {
    font-size: 16px;
    line-height: 1.6;
    color: #333;
    margin-bottom: 24px;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.testimonial-author strong {
    font-size: 15px;
    color: #1a1a1a;
}

.linkedin-icon {
    background: #0077b5;
    color: white;
    width: 24px;
    height: 24px;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    font-weight: 600;
    font-size: 12px;
}

/* FAQ Section */
.faq-section {
    padding: 80px 0;
    background-color: #f8f9fa;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.faq-item {
    background: white;
    border-radius: 12px;
    padding: 32px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.faq-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}

.faq-question {
    font-size: 18px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 12px;
    line-height: 1.4;
}

.faq-answer {
    font-size: 15px;
    line-height: 1.6;
    color: #666;
    margin: 0;
}

/* Responsive Design for New Sections */
@media (max-width: 768px) {
    .companies-grid {
        gap: 24px;
    }
    
    .companies-title,
    .testimonials-title {
        font-size: 28px;
    }
    
    .testimonials-grid,
    .faq-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .testimonial-card,
    .faq-item {
        padding: 24px;
    }
}

/* Apple-inspired Problems Page Styles */
.problems-hero {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    padding: 120px 0 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.problems-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 30% 20%, rgba(255, 255, 255, 0.3) 0%, transparent 50%);
    pointer-events: none;
}

.problems-hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
}

.problems-hero-title {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 56px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 24px;
    letter-spacing: -0.005em;
    line-height: 1.1;
}

.problems-hero-description {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 21px;
    font-weight: 400;
    color: #86868b;
    line-height: 1.4;
    margin: 0;
}

.problems-section-apple {
    background-color: #fbfbfd;
    padding: 60px 0 100px;
    min-height: 70vh;
}

.problems-controls-apple {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    margin-bottom: 48px;
}

.problems-search-apple {
    width: 100%;
    max-width: 500px;
}

.search-input-apple {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    width: 100%;
    padding: 12px 20px;
    border: none;
    border-radius: 16px;
    background-color: rgba(255, 255, 255, 0.9);
    font-size: 16px;
    font-weight: 400;
    color: #1d1d1f;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(0, 0, 0, 0.04);
}

.search-input-apple::placeholder {
    color: #8e8e93;
    font-weight: 400;
}

.search-input-apple:hover {
    background-color: rgba(255, 255, 255, 1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.search-input-apple:focus {
    outline: none;
    background-color: rgba(255, 255, 255, 1);
    box-shadow: 0 0 0 4px rgba(0, 125, 250, 0.15);
    border-color: rgba(0, 125, 250, 0.3);
}

.problems-filters-apple {
    display: flex;
    gap: 16px;
    align-items: center;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 12px 20px;
    border-radius: 20px;
    border: 1px solid rgba(0, 0, 0, 0.04);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.filter-select-apple {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    padding: 8px 16px;
    border: none;
    border-radius: 12px;
    background-color: rgba(255, 255, 255, 0.9);
    font-size: 14px;
    font-weight: 400;
    color: #1d1d1f;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    outline: none;
    appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6,9 12,15 18,9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 16px;
    padding-right: 40px;
    min-width: 140px;
}

.filter-select-apple:hover {
    background-color: rgba(255, 255, 255, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.filter-select-apple:focus {
    background-color: rgba(255, 255, 255, 1);
    box-shadow: 0 0 0 4px rgba(0, 125, 250, 0.15);
}

.problems-table-container-apple {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 18px;
    border: 1px solid rgba(0, 0, 0, 0.04);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
    overflow: hidden;
}

/* Pagination Styles */
.pagination-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    margin-top: 32px;
    padding: 24px;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 18px;
    border: 1px solid rgba(0, 0, 0, 0.04);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
}

.pagination-info {
    font-size: 14px;
    color: #666;
    font-weight: 500;
}

.pagination-controls {
    display: flex;
    align-items: center;
    gap: 8px;
}

.pagination-pages {
    display: flex;
    gap: 4px;
}

.pagination-btn {
    min-width: 36px;
    height: 36px;
    padding: 0 12px;
    border: 1px solid #e0e0e0;
    background: white;
    color: #333;
    font-size: 14px;
    font-weight: 500;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.pagination-btn:hover:not(:disabled) {
    background: #f5f5f5;
    border-color: #d0d0d0;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.pagination-btn:active:not(:disabled) {
    transform: translateY(0);
    box-shadow: none;
}

.pagination-btn.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: #667eea;
    font-weight: 600;
}

.pagination-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.pagination-ellipsis {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 36px;
    height: 36px;
    color: #999;
    font-size: 14px;
    font-weight: 500;
}

.problems-table-apple {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
    table-layout: fixed;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.problems-table-apple thead {
    background: linear-gradient(135deg, rgba(247, 247, 247, 0.8) 0%, rgba(255, 255, 255, 0.9) 100%);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

.problems-table-apple th {
    padding: 20px 24px;
    text-align: left;
    font-weight: 600;
    color: #6e6e73;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.problems-table-apple td {
    padding: 20px 24px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.04);
    vertical-align: middle;
    font-size: 15px;
    font-weight: 400;
    color: #1d1d1f;
    transition: background-color 0.2s ease;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.problems-table-apple tbody tr:hover {
    background-color: rgba(0, 125, 250, 0.03);
}

.problems-table-apple tbody tr:last-child td {
    border-bottom: none;
}

/* Apple-style column widths */
.number-col-apple {
    width: 60px;
    text-align: center;
}

.title-col-apple {
    width: 35%;
    min-width: 200px;
}

.topic-col-apple {
    width: 15%;
    min-width: 100px;
}

.difficulty-col-apple {
    width: 12%;
    min-width: 80px;
}

.views-col-apple {
    width: 10%;
    min-width: 70px;
    text-align: right;
}

.asked-col-apple {
    width: 18%;
    min-width: 120px;
}

/* Apple-style problem title */
.problems-table-apple .problem-title {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-weight: 500;
    color: #1d1d1f;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 15px;
    line-height: 1.4;
    transition: color 0.2s ease;
}

.problems-table-apple .problem-title:hover {
    color: #007dfa;
}

/* Apple-style topic tags */
.problems-table-apple .topic-tag {
    display: inline-block;
    background: linear-gradient(135deg, #1d1d1f 0%, #2d2d2f 100%);
    color: #ffffff;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 0.3px;
    text-transform: uppercase;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* Apple-style difficulty indicators */
.problems-table-apple .difficulty-easy {
    color: #30d158;
    font-weight: 600;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.problems-table-apple .difficulty-medium {
    color: #ff9f0a;
    font-weight: 600;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.problems-table-apple .difficulty-hard {
    color: #ff3b30;
    font-weight: 600;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* Apple-style views count */
.problems-table-apple .views-count {
    color: #86868b;
    font-size: 13px;
    font-weight: 400;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* Apple-style company logos */
.problems-table-apple .company-logo {
    width: 20px;
    height: 20px;
    border-radius: 4px;
    background: linear-gradient(135deg, #f5f5f7 0%, #e5e5e7 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 9px;
    font-weight: 600;
    color: #6e6e73;
    border: 1px solid rgba(0, 0, 0, 0.06);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* Responsive design for Apple-style problems page */
@media (max-width: 768px) {
    .problems-hero {
        padding: 100px 0 60px;
    }
    
    .problems-hero-title {
        font-size: 40px;
    }
    
    .problems-hero-description {
        font-size: 19px;
    }
    
    .problems-search-apple {
        max-width: 100%;
        padding: 0 12px;
    }
    
    .search-input-apple {
        font-size: 16px; /* Prevent zoom on iOS */
        padding: 14px 16px;
    }
    
    .problems-filters-apple {
        flex-direction: column;
        gap: 12px;
        padding: 16px;
    }
    
    .filter-select-apple {
        width: 100%;
        min-width: auto;
    }
    
    .problems-table-container-apple {
        border-radius: 12px;
        margin: 0 -12px;
    }
    
    .problems-table-apple th,
    .problems-table-apple td {
        padding: 16px 12px;
        font-size: 13px;
    }
    
    .problems-hero-title {
        font-size: 32px;
    }
    
    .pagination-container {
        padding: 16px;
        margin-top: 24px;
        border-radius: 12px;
    }
    
    .pagination-info {
        font-size: 13px;
        text-align: center;
    }
    
    .pagination-controls {
        flex-wrap: wrap;
        gap: 6px;
        justify-content: center;
    }
    
    .pagination-btn {
        min-width: 32px;
        height: 32px;
        padding: 0 10px;
        font-size: 13px;
    }
    
    .pagination-ellipsis {
        min-width: 32px;
        height: 32px;
        font-size: 13px;
    }
}

/* Resources Page Styles */
.resources-hero-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 120px 0 80px;
    text-align: center;
    color: white;
}

.resources-hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.resources-hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.resources-hero-description {
    font-size: 20px;
    opacity: 0.95;
    line-height: 1.6;
}

.resources-content-section {
    padding: 80px 0;
    background-color: #fbfbfd;
    min-height: 60vh;
}

.resource-category-section {
    margin-bottom: 64px;
}

.resource-category-section:last-child {
    margin-bottom: 0;
}

.resource-category-header {
    margin-bottom: 32px;
}

.resource-category-title {
    font-size: 32px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.resource-category-divider {
    width: 80px;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
}

.resources-list {
    list-style: none;
    counter-reset: resource-counter;
    padding: 0;
    margin: 0;
}

.resource-list-item {
    counter-increment: resource-counter;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    background: white;
    border: 1px solid #e5e7eb;
    margin-bottom: 12px;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.resource-list-item:hover {
    border-color: #667eea;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.1);
}

.resource-list-item::before {
    content: counter(resource-counter);
    font-size: 18px;
    font-weight: 700;
    color: #667eea;
    min-width: 32px;
    margin-right: 16px;
}

.resource-list-content {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 12px;
}

.resource-title-link {
    font-size: 16px;
    font-weight: 500;
    color: #1a1a1a;
    text-decoration: none;
    transition: color 0.2s ease;
}

.resource-title-link:hover {
    color: #667eea;
    text-decoration: underline;
}

.resource-size {
    font-size: 14px;
    color: #6b7280;
    white-space: nowrap;
}

.btn-download {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}

.btn-download:hover {
    background: #5568d3;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.btn-download svg {
    flex-shrink: 0;
}

.resources-loading,
.resources-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 80px 20px;
    color: #666;
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 16px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.empty-icon {
    font-size: 64px;
    margin-bottom: 16px;
}

.resources-empty h3 {
    font-size: 24px;
    margin-bottom: 8px;
    color: #333;
}

.resources-empty p {
    font-size: 16px;
    color: #666;
}


.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.btn-secondary {
    background: #f5f5f5;
    color: #333;
    border: 1px solid #e0e0e0;
}

.btn-secondary:hover {
    background: #e8e8e8;
    border-color: #d0d0d0;
}

/* PDF Preview Modal */
.pdf-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.pdf-modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(8px);
}

.pdf-modal-content {
    position: relative;
    background: white;
    border-radius: 16px;
    width: 90%;
    max-width: 1200px;
    height: 90vh;
    max-height: 900px;
    display: flex;
    flex-direction: column;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.pdf-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-bottom: 1px solid #e0e0e0;
}

.pdf-modal-title {
    font-size: 20px;
    font-weight: 600;
    color: #1d1d1f;
    margin: 0;
}

.pdf-modal-close {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    border: none;
    background: #f5f5f5;
    color: #666;
    font-size: 20px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.pdf-modal-close:hover {
    background: #e8e8e8;
    color: #333;
}

.pdf-modal-body {
    flex: 1;
    overflow: hidden;
    padding: 0;
}

.pdf-pages-container {
    padding: 20px;
    max-height: 100%;
    overflow-y: auto;
}

.pdf-page-wrapper {
    margin-bottom: 30px;
}

.pdf-page-wrapper:last-child {
    margin-bottom: 0;
}

.pdf-page-label {
    text-align: center;
    font-size: 14px;
    color: #666;
    margin-bottom: 10px;
    font-weight: 500;
}

.pdf-canvas {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    border-radius: 4px;
}

.pdf-modal-footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 12px;
    padding: 20px 24px;
    border-top: 1px solid #e0e0e0;
}

/* Responsive Styles for Resources Page */
@media (max-width: 768px) {
    .resources-hero-section {
        padding: 80px 0 60px;
    }
    
    .resources-hero-title {
        font-size: 36px;
    }
    
    .resources-hero-description {
        font-size: 18px;
    }
    
    .resources-content-section {
        padding: 40px 0;
    }
    
    .resource-category-section {
        margin-bottom: 48px;
    }
    
    .resource-category-title {
        font-size: 24px;
    }
    
    .resource-list-item {
        flex-direction: column;
        align-items: flex-start;
        padding: 16px;
    }
    
    .resource-list-item::before {
        margin-bottom: 8px;
    }
    
    .resource-list-content {
        flex-direction: column;
        align-items: flex-start;
        width: 100%;
        gap: 8px;
        margin-bottom: 12px;
    }
    
    .btn-download {
        width: 100%;
        justify-content: center;
    }
    
    .pdf-modal-content {
        width: 100%;
        height: 100%;
        border-radius: 0;
        max-height: 100vh;
    }
    
    
    .pdf-modal-header,
    .pdf-modal-footer {
        padding: 16px;
    }
    
    .pdf-modal-footer {
        flex-direction: column;
    }
    
    .pdf-modal-footer .btn {
        width: 100%;
    }
}

/* Auth Page Styles */
.auth-section-full {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-top: 100px;
    padding-bottom: 40px;
}

.auth-card-centered {
    background: white;
    border-radius: 16px;
    padding: 48px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
    width: 100%;
    max-width: 400px;
    border: 1px solid #e5e5e5;
}

.verification-message {
    background: #f0f9ff;
    border: 1px solid #0ea5e9;
    color: #0369a1;
    padding: 16px;
    border-radius: 8px;
    margin-bottom: 24px;
    text-align: center;
}

.social-auth {
    margin-top: 24px;
}

.btn-google {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    width: 100%;
    padding: 12px 24px;
    border: 1px solid #e5e5e5;
    background: white;
    color: #333;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.2s ease;
}

.btn-google:hover {
    background: #f9f9f9;
    border-color: #d1d5db;
}

/* User Dropdown Styles */
.user-dropdown {
    position: relative;
    display: inline-block;
}

.user-button {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    background: #f8f9fa;
    border: 1px solid #e5e5e5;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: #333;
    text-decoration: none;
    transition: all 0.2s ease;
}

.user-button:hover {
    background: #e9ecef;
    border-color: #d1d5db;
}

.user-email {
    max-width: 150px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.dropdown-arrow {
    width: 16px;
    height: 16px;
    transition: transform 0.2s ease;
}

.user-dropdown.open .dropdown-arrow {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background: white;
    border: 1px solid #e5e5e5;
    border-radius: 8px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
    min-width: 200px;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.2s ease;
}

.user-dropdown.open .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-item {
    display: block;
    padding: 12px 16px;
    color: #333;
    text-decoration: none;
    font-size: 14px;
    border-bottom: 1px solid #f1f3f4;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.dropdown-item:last-child {
    border-bottom: none;
}

.dropdown-item:hover {
    background: #f8f9fa;
}

.dropdown-item.danger {
    color: #dc3545;
}

.dropdown-item.danger:hover {
    background: #fef2f2;
}

.dropdown-item.user-status {
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: default;
    padding: 12px 16px;
}

.dropdown-item.user-status:hover {
    background: transparent;
}

.status-label {
    color: #666;
    font-weight: 500;
}

.status-badge {
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-badge.free {
    background: #f3f4f6;
    color: #6b7280;
}

.status-badge.premium {
    background: #fef3c7;
    color: #d97706;
}

.dropdown-divider {
    height: 1px;
    background: #e5e7eb;
    margin: 4px 0;
}

/* Pulse animation for highlighting buttons */
@keyframes pulse {
    0% {
        transform: scale(1);
        box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.7);
    }
    50% {
        transform: scale(1.02);
        box-shadow: 0 0 0 10px rgba(59, 130, 246, 0.3);
    }
    100% {
        transform: scale(1);
        box-shadow: 0 0 0 0 rgba(59, 130, 246, 0);
    }
}

/* Access Control Messages */
.access-message {
    margin: 24px 0;
}

.access-card {
    background: #f8fafc;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    padding: 32px;
    text-align: center;
    max-width: 500px;
    margin: 0 auto;
}

.access-card.premium {
    background: linear-gradient(135deg, #fef3c7 0%, #fed7aa 100%);
    border-color: #f59e0b;
}

.access-card h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 16px;
    color: #1f2937;
}

.access-card.premium h3 {
    color: #92400e;
}

.access-card p {
    font-size: 16px;
    color: #6b7280;
    margin-bottom: 24px;
    line-height: 1.6;
}

.access-card.premium p {
    color: #a16207;
}

.access-card .btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    font-weight: 500;
}

/* Problem solution section styling */
.problem-solution {
    margin-top: 32px;
    padding: 24px;
    background: #f9fafb;
    border-radius: 8px;
    border-left: 4px solid #3b82f6;
}

.problem-solution h2 {
    font-size: 20px;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 16px;
}

.solution-content {
    color: #374151;
    line-height: 1.7;
}

.solution-content p {
    margin-bottom: 16px;
}

/* Settings Page Styles */
.settings-hero {
    padding: 80px 0 40px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.settings-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 12px;
}

.settings-description {
    font-size: 18px;
    opacity: 0.9;
}

.settings-section {
    padding: 60px 0 100px;
    background-color: #f8f9fa;
}

.settings-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    max-width: 700px;
    margin: 0 auto;
    padding: 40px;
    border: 1px solid #e5e5e5;
}

.settings-group {
    margin-bottom: 48px;
}

.settings-group:last-child {
    margin-bottom: 0;
}

.settings-group-title {
    font-size: 24px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 2px solid #e5e5e5;
}

.settings-item {
    margin-bottom: 24px;
}

.settings-label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: #666;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.settings-value {
    font-size: 16px;
    color: #1a1a1a;
    padding: 12px 0;
}

.settings-form .form-group {
    margin-bottom: 24px;
}

.settings-form .form-label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: #333;
    margin-bottom: 8px;
}

.settings-form .form-input {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.settings-form .form-input:focus {
    outline: none;
    border-color: #007dfa;
    box-shadow: 0 0 0 3px rgba(0, 125, 250, 0.1);
}

.settings-form .form-actions {
    margin-top: 32px;
}

.settings-message {
    margin-top: 16px;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
}

.settings-message.success {
    background-color: #d1fae5;
    color: #065f46;
    border: 1px solid #6ee7b7;
}

.settings-message.error {
    background-color: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

/* Responsive Styles for Settings Page */
@media (max-width: 768px) {
    .settings-hero {
        padding: 60px 0 30px;
    }
    
    .settings-title {
        font-size: 28px;
    }
    
    .settings-card {
        padding: 24px;
        border-radius: 0;
    }
    
    .settings-group-title {
        font-size: 20px;
    }
}

/* Bookmark Styles */
.bookmark-btn {
    background: none;
    border: none;
    font-size: 22px;
    cursor: pointer;
    padding: 4px 8px;
    transition: all 0.2s ease;
    color: #d1d5db;
    line-height: 1;
}

.bookmark-btn:hover {
    transform: scale(1.2);
    color: #fbbf24;
}

.bookmark-btn.bookmarked {
    color: #fbbf24;
    animation: bookmarkPop 0.3s ease;
}

@keyframes bookmarkPop {
    0% { transform: scale(1); }
    50% { transform: scale(1.3); }
    100% { transform: scale(1); }
}

.bookmark-col {
    text-align: center;
    vertical-align: middle;
    width: 50px;
}

.bookmark-col-apple {
    text-align: center;
    vertical-align: middle;
    width: 50px;
}

/* Completed button styles (table) */
.completed-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 18px;
    color: #d1d5db;
    transition: all 0.2s ease;
    padding: 4px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: 4px;
}

.completed-btn:hover {
    color: #10b981;
    background-color: #f0fdf4;
}

.completed-btn.completed {
    color: #10b981;
    font-weight: bold;
}

.completed-btn.completed:hover {
    color: #059669;
    background-color: #dcfce7;
}

.status-col {
    width: 50px;
    text-align: center;
}

.status-col-apple {
    width: 50px;
}

/* Completed button on detail page */
.completed-detail-btn {
    background: none;
    border: 1px solid #e5e7eb;
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    color: #6b7280;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s ease;
    height: 36px;
}

.completed-detail-btn:hover {
    border-color: #10b981;
    color: #059669;
    background-color: #f0fdf4;
}

.completed-detail-btn.completed {
    border-color: #10b981;
    color: #059669;
    background-color: #d1fae5;
}

.completed-detail-btn #completedIcon {
    font-size: 16px;
    line-height: 1;
    font-weight: bold;
}

/* Bookmark button on detail page */
.bookmark-detail-btn {
    background: none;
    border: 1px solid #e5e7eb;
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 18px;
    color: #d1d5db;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    min-width: 40px;
    height: 36px;
}

.bookmark-detail-btn:hover {
    border-color: #fbbf24;
    color: #f59e0b;
    background-color: #fffbeb;
}

.bookmark-detail-btn.bookmarked {
    border-color: #fbbf24;
    color: #f59e0b;
    background-color: #fef3c7;
}

.bookmark-detail-btn #bookmarkIcon {
    font-size: 18px;
    line-height: 1;
}

/* Notification Styles */
.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 12px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 9999;
    font-size: 14px;
    font-weight: 500;
    opacity: 0;
    transform: translateX(400px);
    transition: all 0.3s ease;
}

.notification.show {
    opacity: 1;
    transform: translateX(0);
}

.notification-success {
    background: #10b981;
    color: white;
}

.notification-error {
    background: #ef4444;
    color: white;
}

.notification-info {
    background: #3b82f6;
    color: white;
}

/* Comments Section Styles */
.comments-section {
    margin-top: 40px;
    background: #ffffff;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    border: 1px solid #e5e5e5;
    padding: 40px;
}

.comments-title {
    font-size: 24px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 24px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.comments-count {
    font-size: 18px;
    font-weight: 400;
    color: #6b7280;
}

/* Comment Form */
.comment-form-container {
    margin-bottom: 32px;
}

.comment-form-auth {
    padding: 20px;
    background: #f9fafb;
    border-radius: 8px;
    text-align: center;
    border: 1px solid #e5e7eb;
}

.comment-form-auth p {
    margin: 0;
    color: #6b7280;
}

.comment-form-auth a {
    color: #007dfa;
    text-decoration: none;
    font-weight: 500;
}

.comment-form-auth a:hover {
    text-decoration: underline;
}

.comment-form {
    background: #ffffff;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    padding: 20px;
}

.comment-textarea {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    font-family: inherit;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    resize: vertical;
    min-height: 100px;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.comment-textarea:focus {
    outline: none;
    border-color: #007dfa;
    box-shadow: 0 0 0 3px rgba(0, 125, 250, 0.1);
}

.comment-form-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 12px;
}

.char-count {
    font-size: 13px;
    color: #6b7280;
}

/* Comments List */
.comments-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.comments-loading,
.comments-empty {
    text-align: center;
    padding: 40px 20px;
    color: #6b7280;
}

/* Individual Comment */
.comment-item {
    background: #ffffff;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    padding: 20px;
    transition: box-shadow 0.2s ease;
}

.comment-item:hover {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.comment-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
}

.comment-author {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.author-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

.author-name {
    font-weight: 600;
    color: #1a1a1a;
    font-size: 14px;
}

.comment-time {
    font-size: 13px;
    color: #6b7280;
}

.edited-badge {
    font-size: 12px;
    color: #9ca3af;
    font-style: italic;
}

.comment-actions {
    display: flex;
    gap: 8px;
}

.comment-action-btn {
    background: none;
    border: none;
    color: #6b7280;
    font-size: 13px;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.comment-action-btn:hover {
    background: #f3f4f6;
    color: #1a1a1a;
}

.comment-action-btn.delete:hover {
    background: #fee2e2;
    color: #dc2626;
}

.comment-body {
    color: #374151;
    line-height: 1.6;
    font-size: 15px;
}

.comment-body p {
    margin: 0;
    white-space: pre-wrap;
    word-wrap: break-word;
}

/* Responsive Comments */
@media (max-width: 768px) {
    .comments-section {
        margin-top: 24px;
        padding: 24px;
        border-radius: 0;
        box-shadow: none;
    }
    
    .comments-title {
        font-size: 20px;
    }
    
    .comment-form {
        padding: 16px;
    }
    
    .comment-item {
        padding: 16px;
    }
    
    .comment-header {
        flex-direction: column;
        gap: 12px;
    }
    
    .comment-actions {
        width: 100%;
        justify-content: flex-start;
    }
    
    .author-avatar {
        width: 32px;
        height: 32px;
        font-size: 13px;
    }
}

@media (max-width: 480px) {
    .comments-section {
        padding: 20px;
    }
}

/* Responsive Styles for Centered Problem Detail */
@media (max-width: 768px) {
    .problem-detail-card {
        border-radius: 0;
        box-shadow: none;
    }
    
    .problem-detail-header-centered {
        padding: 32px 24px 24px;
    }
    
    .problem-title-centered {
        font-size: 24px;
    }
    
    .problem-meta-centered {
        flex-direction: column;
        gap: 8px;
    }
    
    .problem-stats-centered {
        flex-direction: column;
        gap: 6px;
    }
    
    .problem-content {
        padding: 24px;
    }
    
    .problem-description {
        padding: 20px;
    }
    
    .back-section-top {
        padding: 16px 0 8px;
    }
}

@media (max-width: 480px) {
    .problem-title-centered {
        font-size: 22px;
    }
    
    .problem-description {
        padding: 16px;
    }
    
    .problem-solution {
        padding: 20px;
    }
    
    .problem-content {
        padding: 20px;
    }
    
    .problem-detail-header-centered {
        padding: 24px 20px 20px;
    }
}

/* ============================================================================
   QUESTION OF THE DAY STYLES
   ============================================================================ */

/* QOTD Section (Homepage) */
.qotd-section {
    padding: 40px 0;
    background: #f9fafb;
}

.qotd-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.15);
    color: white;
}

.qotd-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.qotd-badge {
    display: flex;
    align-items: center;
    gap: 8px;
}

.qotd-icon {
    font-size: 24px;
}

.qotd-label {
    font-size: 18px;
    font-weight: 600;
}

.qotd-date {
    font-size: 14px;
    opacity: 0.9;
}

.qotd-content {
    min-height: 150px;
}

.qotd-loading,
.qotd-error {
    text-align: center;
    padding: 40px 20px;
    opacity: 0.8;
}

.qotd-problem {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.qotd-meta {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    align-items: center;
}

.qotd-topic {
    background: rgba(255, 255, 255, 0.2);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 13px;
}

.qotd-company {
    background: rgba(255, 255, 255, 0.2);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 13px;
}

.qotd-completed-badge {
    background: #10b981;
    color: white;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 600;
}

.qotd-title {
    margin: 0;
    font-size: 24px;
    font-weight: 600;
}

.qotd-title a {
    color: white;
    text-decoration: none;
    transition: opacity 0.2s ease;
}

.qotd-title a:hover {
    opacity: 0.8;
}

.qotd-description {
    font-size: 15px;
    line-height: 1.6;
    opacity: 0.95;
    margin: 0;
}

.qotd-btn {
    align-self: flex-start;
    background: white;
    color: #667eea;
    font-weight: 600;
}

.qotd-btn:hover {
    background: #f9fafb;
    color: #667eea;
}

/* QOTD Banner (Problems Page) */
.qotd-banner-section {
    padding: 24px 0;
    background: #f9fafb;
}

.qotd-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 12px;
    padding: 16px 24px;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.15);
}

.qotd-banner-loading {
    text-align: center;
    color: white;
    padding: 8px;
    opacity: 0.9;
}

.qotd-banner-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
}

.qotd-banner-left {
    display: flex;
    align-items: center;
    gap: 16px;
    flex: 1;
}

.qotd-banner-icon {
    font-size: 28px;
}

.qotd-banner-text {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.qotd-banner-label {
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: rgba(255, 255, 255, 0.8);
    font-weight: 600;
}

.qotd-banner-title {
    font-size: 18px;
    font-weight: 600;
    color: white;
    text-decoration: none;
    transition: opacity 0.2s ease;
}

.qotd-banner-title:hover {
    opacity: 0.8;
}

.qotd-banner-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

.qotd-banner-btn {
    background: white;
    color: #667eea;
    font-weight: 600;
    padding: 8px 20px;
    white-space: nowrap;
}

.qotd-banner-btn:hover {
    background: #f9fafb;
    color: #667eea;
}

.btn-sm {
    font-size: 14px;
    padding: 6px 16px;
}

/* Responsive QOTD */
@media (max-width: 768px) {
    .qotd-section {
        padding: 24px 0;
    }
    
    .qotd-card {
        padding: 24px 20px;
        border-radius: 12px;
    }
    
    .qotd-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
    }
    
    .qotd-title {
        font-size: 20px;
    }
    
    .qotd-banner-section {
        padding: 16px 0;
    }
    
    .qotd-banner {
        padding: 16px;
    }
    
    .qotd-banner-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
    
    .qotd-banner-left {
        width: 100%;
    }
    
    .qotd-banner-right {
        width: 100%;
        justify-content: space-between;
    }
    
    .qotd-banner-btn {
        flex: 1;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .qotd-card {
        padding: 20px 16px;
    }
    
    .qotd-icon,
    .qotd-banner-icon {
        font-size: 20px;
    }
    
    .qotd-label {
        font-size: 16px;
    }
    
    .qotd-title {
        font-size: 18px;
    }
    
    .qotd-banner-title {
        font-size: 16px;
    }
    
    .qotd-meta {
        gap: 8px;
    }
}

/* ============================================================================
   PROGRESS PAGE STYLES
   ============================================================================ */

/* Progress Hero */
.progress-hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 60px 0 40px;
    color: white;
}

.progress-hero-title {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 8px;
    text-align: center;
}

.progress-hero-description {
    font-size: 18px;
    opacity: 0.9;
    text-align: center;
}

/* Progress Section */
.progress-section {
    padding: 40px 0 80px;
    background: #f9fafb;
}

.progress-grid {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
}

/* Stats Cards */
.stats-card {
    background: white;
    border-radius: 12px;
    padding: 24px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    border: 1px solid #e5e7eb;
}

/* Progress Chart Card */
.progress-chart-card {
    margin-bottom: 24px;
}

.progress-chart-container {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.progress-circle {
    width: 250px;
    height: 250px;
}

.progress-segment {
    transition: stroke-dasharray 1s ease, stroke-dashoffset 1s ease;
}

.progress-number {
    font-size: 42px;
    font-weight: 700;
    fill: #1a1a1a;
}

.progress-total {
    font-size: 20px;
    fill: #6b7280;
}

.progress-label {
    font-size: 14px;
    fill: #6b7280;
    font-weight: 500;
}

/* Difficulty Breakdown Card */
.difficulty-breakdown-card {
    margin-bottom: 24px;
}

.difficulty-item {
    margin-bottom: 20px;
}

.difficulty-item:last-child {
    margin-bottom: 0;
}

.difficulty-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.difficulty-badge {
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
}

.difficulty-count {
    font-size: 14px;
    font-weight: 600;
    color: #1a1a1a;
}

.difficulty-progress-bar {
    width: 100%;
    height: 8px;
    background: #e5e7eb;
    border-radius: 4px;
    overflow: hidden;
}

.difficulty-progress-fill {
    height: 100%;
    border-radius: 4px;
    transition: width 0.6s ease;
}

.difficulty-progress-easy {
    background: #10b981;
}

.difficulty-progress-medium {
    background: #f59e0b;
}

.difficulty-progress-hard {
    background: #ef4444;
}

/* Calendar Card */
.calendar-card {
    margin-bottom: 24px;
}

.calendar-header {
    margin-bottom: 20px;
}

.calendar-title {
    font-size: 14px;
    color: #6b7280;
    margin-bottom: 8px;
}

.calendar-title strong {
    color: #1a1a1a;
    font-weight: 600;
}

.calendar-stats {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.calendar-stat {
    font-size: 12px;
    color: #6b7280;
}

.calendar-stat strong {
    color: #1a1a1a;
    font-weight: 600;
}

.calendar-grid {
    display: flex;
    gap: 3px;
    overflow-x: auto;
    padding-bottom: 8px;
}

.calendar-week {
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.calendar-day {
    width: 11px;
    height: 11px;
    border-radius: 2px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.calendar-day-empty {
    background: transparent;
}

.calendar-day-0 {
    background: #ebedf0;
}

.calendar-day-1 {
    background: #9be9a8;
}

.calendar-day-2 {
    background: #40c463;
}

.calendar-day-3 {
    background: #30a14e;
}

.calendar-day-4 {
    background: #216e39;
}

.calendar-day:not(.calendar-day-empty):hover {
    outline: 2px solid rgba(0, 0, 0, 0.2);
    outline-offset: 1px;
}

.calendar-legend {
    display: flex;
    align-items: center;
    gap: 4px;
    margin-top: 12px;
    font-size: 11px;
    color: #6b7280;
}

.legend-label {
    margin: 0 4px;
}

.legend-item {
    width: 11px;
    height: 11px;
    border-radius: 2px;
}

.legend-0 {
    background: #ebedf0;
}

.legend-1 {
    background: #9be9a8;
}

.legend-2 {
    background: #40c463;
}

.legend-3 {
    background: #30a14e;
}

.legend-4 {
    background: #216e39;
}

/* Recent Activity Card */
.recent-activity-card {
    position: sticky;
    top: 20px;
}

.recent-activity-title {
    font-size: 16px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 16px;
}

.recent-activity-list {
    max-height: 600px;
    overflow-y: auto;
}

.activity-item {
    padding: 12px 0;
    border-bottom: 1px solid #e5e7eb;
}

.activity-item:last-child {
    border-bottom: none;
}

.activity-title {
    display: block;
    font-size: 14px;
    color: #1a1a1a;
    font-weight: 500;
    margin-bottom: 6px;
    text-decoration: none;
    transition: color 0.2s ease;
}

.activity-title:hover {
    color: #667eea;
}

.activity-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
}

.activity-time {
    color: #9ca3af;
}

.loading-message,
.no-activity {
    text-align: center;
    color: #9ca3af;
    padding: 20px;
    font-size: 14px;
}

.error-message {
    text-align: center;
    padding: 40px 20px;
    color: #ef4444;
}

/* Responsive Progress Page */
@media (max-width: 1024px) {
    .progress-grid {
        grid-template-columns: 1fr;
    }
    
    .recent-activity-card {
        position: static;
    }
}

@media (max-width: 768px) {
    .progress-hero {
        padding: 40px 0 30px;
    }
    
    .progress-hero-title {
        font-size: 28px;
    }
    
    .progress-hero-description {
        font-size: 16px;
    }
    
    .progress-section {
        padding: 24px 0 40px;
    }
    
    .stats-card {
        padding: 20px;
    }
    
    .progress-circle {
        width: 200px;
        height: 200px;
    }
    
    .progress-number {
        font-size: 36px;
    }
    
    .calendar-grid {
        gap: 2px;
    }
    
    .calendar-week {
        gap: 2px;
    }
    
    .calendar-day {
        width: 10px;
        height: 10px;
    }
    
    .calendar-stats {
        flex-direction: column;
        gap: 4px;
    }
}

@media (max-width: 480px) {
    .progress-hero-title {
        font-size: 24px;
    }
    
    .stats-card {
        padding: 16px;
        border-radius: 8px;
    }
    
    .progress-circle {
        width: 180px;
        height: 180px;
    }
    
    .progress-number {
        font-size: 32px;
    }
    
    .calendar-day {
        width: 8px;
        height: 8px;
    }
    
    .legend-item {
        width: 10px;
        height: 10px;
    }
}