/* ============================================
   H Heuristics Data Marketplace
   Design System & Styles
   ============================================ */

/* CSS Custom Properties */
:root {
    /* Colors - Dark, sophisticated palette */
    --color-bg-primary: #0d1117;
    --color-bg-secondary: #161b22;
    --color-bg-tertiary: #1c2128;
    --color-bg-elevated: #21262d;
    
    --color-text-primary: #f0f6fc;
    --color-text-secondary: #8b949e;
    --color-text-tertiary: #6e7681;
    
    --color-accent: #58a6b1;
    --color-accent-muted: #3d6d73;
    --color-accent-light: rgba(88, 166, 177, 0.15);
    
    --color-border: rgba(240, 246, 252, 0.1);
    --color-border-emphasis: rgba(240, 246, 252, 0.2);
    
    --color-success: #3fb950;
    --color-warning: #d29922;
    --color-error: #f85149;
    
    /* Typography */
    --font-serif: 'Cormorant Garamond', Georgia, 'Times New Roman', serif;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 400ms ease;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.6);
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

img {
    max-width: 100%;
    height: auto;
}

ul, ol {
    list-style: none;
}

/* Container */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-serif);
    font-weight: 500;
    line-height: 1.2;
}

.section-label {
    display: inline-block;
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-md);
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    color: var(--color-text-primary);
    margin-bottom: var(--space-lg);
}

.section-description {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    max-width: 600px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-xl);
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    transition: all var(--transition-base);
    white-space: nowrap;
}

.btn-primary {
    background-color: var(--color-text-primary);
    color: var(--color-bg-primary);
}

.btn-primary:hover {
    background-color: var(--color-accent);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-text-primary);
    border: 1px solid var(--color-border-emphasis);
}

.btn-secondary:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.btn-accent {
    background-color: var(--color-accent);
    color: var(--color-bg-primary);
}

.btn-accent:hover {
    background-color: var(--color-accent-muted);
}

.btn-block {
    width: 100%;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* ============================================
   Header & Navigation
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(13, 17, 23, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.logo-mark {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: var(--color-text-primary);
    color: var(--color-bg-primary);
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
}

.logo-text {
    font-family: var(--font-serif);
    font-size: 1.375rem;
    font-weight: 500;
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-link {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.nav-link:hover {
    color: var(--color-text-primary);
}

.cart-btn {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.cart-btn:hover {
    color: var(--color-text-primary);
}

.cart-count {
    position: absolute;
    top: 2px;
    right: 2px;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 18px;
    height: 18px;
    padding: 0 5px;
    font-size: 0.6875rem;
    font-weight: 600;
    background: var(--color-accent);
    color: var(--color-bg-primary);
    border-radius: var(--radius-full);
    opacity: 0;
    transform: scale(0.8);
    transition: all var(--transition-fast);
}

.cart-count.visible {
    opacity: 1;
    transform: scale(1);
}

.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}

.mobile-toggle span {
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    transition: all var(--transition-base);
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-toggle {
        display: flex;
    }
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-4xl) 0;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(88, 166, 177, 0.15), transparent),
        radial-gradient(ellipse 60% 40% at 100% 50%, rgba(88, 166, 177, 0.08), transparent),
        linear-gradient(180deg, var(--color-bg-primary) 0%, var(--color-bg-secondary) 100%);
}

.hero-bg::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.02'%3E%3Ccircle cx='30' cy='30' r='1'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    position: relative;
    text-align: center;
    max-width: 900px;
}

.hero-label {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-lg);
    animation: fadeInUp 0.8s ease forwards;
}

.hero-title {
    font-size: clamp(2.5rem, 7vw, 4.5rem);
    font-weight: 400;
    line-height: 1.1;
    margin-bottom: var(--space-xl);
    animation: fadeInUp 0.8s ease 0.1s forwards;
    opacity: 0;
}

.hero-description {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    max-width: 700px;
    margin: 0 auto var(--space-2xl);
    animation: fadeInUp 0.8s ease 0.2s forwards;
    opacity: 0;
}

.hero-actions {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.8s ease 0.3s forwards;
    opacity: 0;
}

.hero-scroll {
    position: absolute;
    bottom: var(--space-2xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
    animation: fadeIn 1s ease 0.6s forwards;
    opacity: 0;
}

@media (max-width: 768px) {
    .hero-scroll {
        display: none;
    }
}

.hero-scroll span {
    font-size: 0.75rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-tertiary);
}

.scroll-line {
    width: 1px;
    height: 60px;
    background: linear-gradient(180deg, var(--color-accent), transparent);
    animation: scrollPulse 2s ease-in-out infinite;
}

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

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

@keyframes scrollPulse {
    0%, 100% { opacity: 1; transform: scaleY(1); }
    50% { opacity: 0.5; transform: scaleY(0.8); }
}

/* ============================================
   Stats Section
   ============================================ */
.stats {
    padding: var(--space-3xl) 0;
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-family: var(--font-serif);
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 500;
    color: var(--color-text-primary);
    margin-bottom: var(--space-xs);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
}

@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ============================================
   Datasets Section
   ============================================ */
.datasets {
    padding: var(--space-4xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-header .section-description {
    margin: 0 auto;
}

/* Category Filters */
.category-filters {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-2xl);
}

.filter-btn {
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.filter-btn:hover {
    border-color: var(--color-border-emphasis);
    color: var(--color-text-primary);
}

.filter-btn.active {
    background: var(--color-accent);
    border-color: var(--color-accent);
    color: var(--color-bg-primary);
}

/* Dataset Grid */
.dataset-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: var(--space-lg);
}

.dataset-card {
    position: relative;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    transition: all var(--transition-base);
    cursor: pointer;
}

.dataset-card:hover {
    border-color: var(--color-accent-muted);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.dataset-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
    flex-wrap: wrap;
}

.dataset-category {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-accent);
    background: var(--color-accent-light);
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-sm);
}

.dataset-tier {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    padding: 0 12px;
    border-radius: var(--radius-sm);
    white-space: nowrap;
    height: 28px;
}

.tier-core {
    background: linear-gradient(135deg, #2d5a3d, #1a3d27);
    color: #7ecea0;
    border: 1px solid #3d7a52;
}

.tier-advanced {
    background: linear-gradient(135deg, #4a3d6e, #2d2548);
    color: #b4a0e8;
    border: 1px solid #6a5a8e;
}

.tier-institutional {
    background: linear-gradient(135deg, #6e5a2d, #48391a);
    color: #e8d4a0;
    border: 1px solid #8e7a4a;
}

/* Ensure category and tier badges align */
.dataset-category {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 28px;
    padding: 0 10px;
}

.modal-header-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    align-items: center;
    margin-bottom: var(--space-md);
}

.modal-header-tags .modal-category,
.modal-header-tags .dataset-tier {
    margin: 0;
}

.dataset-title {
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: var(--space-sm);
    line-height: 1.3;
}

.dataset-description {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-lg);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.dataset-meta {
    display: flex;
    gap: var(--space-lg);
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
    margin-bottom: var(--space-lg);
}

.dataset-meta-item {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.dataset-meta-label {
    font-size: 0.6875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
}

.dataset-meta-value {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-primary);
}

.dataset-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.dataset-price {
    font-family: var(--font-serif);
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--color-text-primary);
}

.dataset-actions {
    display: flex;
    gap: var(--space-sm);
}

.btn-add-cart {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-md);
    font-size: 0.8125rem;
    font-weight: 500;
    background: var(--color-accent);
    color: var(--color-bg-primary);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.btn-add-cart:hover {
    background: var(--color-text-primary);
}

.btn-add-cart.added {
    background: var(--color-success);
}

.btn-preview {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}

.btn-preview:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

@media (max-width: 640px) {
    .dataset-grid {
        grid-template-columns: 1fr;
    }
}

/* ============================================
   Features Section
   ============================================ */
.features {
    padding: var(--space-4xl) 0;
    background: var(--color-bg-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
}

.feature-card {
    padding: var(--space-xl);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
}

.feature-card:hover {
    border-color: var(--color-accent-muted);
    transform: translateY(-4px);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--color-accent-light);
    border-radius: var(--radius-md);
    color: var(--color-accent);
    margin-bottom: var(--space-lg);
}

.feature-title {
    font-size: 1.125rem;
    font-weight: 500;
    margin-bottom: var(--space-sm);
}

.feature-description {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
}

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 640px) {
    .features-grid {
        grid-template-columns: 1fr;
    }
}

/* ============================================
   Sources Section
   ============================================ */
.sources {
    padding: var(--space-3xl) 0;
    background: var(--color-bg-tertiary);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.sources-content {
    text-align: center;
}

.sources-content h3 {
    font-size: 1.25rem;
    margin-bottom: var(--space-sm);
}

.sources-content > p {
    color: var(--color-text-secondary);
    margin-bottom: var(--space-xl);
}

.sources-list {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-md);
}

.sources-list span {
    padding: var(--space-sm) var(--space-lg);
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

/* Mobile nav */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--color-bg-primary);
        padding: var(--space-lg);
        flex-direction: column;
        gap: var(--space-md);
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
    }
    
    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .mobile-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .mobile-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
}

/* ============================================
   CTA Section
   ============================================ */
.cta {
    padding: var(--space-4xl) 0;
}

.cta-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
    padding: var(--space-3xl);
    background: linear-gradient(135deg, var(--color-bg-secondary), var(--color-bg-tertiary));
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
}

.cta-title {
    font-size: clamp(1.5rem, 4vw, 2rem);
    margin-bottom: var(--space-md);
}

.cta-description {
    font-size: 1.0625rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-xl);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    padding: var(--space-4xl) 0 var(--space-xl);
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: var(--space-3xl);
    margin-bottom: var(--space-3xl);
}

.footer-brand .logo {
    margin-bottom: var(--space-md);
}

.footer-tagline {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    font-style: italic;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-lg);
}

.footer-address {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
    line-height: 1.8;
}

.footer-links {
    display: flex;
    gap: var(--space-3xl);
}

.footer-col h4 {
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-lg);
}

.footer-col ul {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.footer-col a {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.footer-col a:hover {
    color: var(--color-text-primary);
}

.footer-bottom {
    padding-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
    text-align: center;
}

.footer-bottom p {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
}

@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
    }
    
    .footer-links {
        flex-direction: row;
        gap: var(--space-2xl);
    }
}

/* ============================================
   Cart Sidebar
   ============================================ */
.cart-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 1100;
}

.cart-overlay.active {
    opacity: 1;
    visibility: visible;
}

.cart-sidebar {
    position: fixed;
    top: 0;
    right: 0;
    width: 100%;
    max-width: 420px;
    height: 100%;
    background: var(--color-bg-secondary);
    border-left: 1px solid var(--color-border);
    transform: translateX(100%);
    transition: transform var(--transition-base);
    z-index: 1101;
    display: flex;
    flex-direction: column;
}

.cart-sidebar.active {
    transform: translateX(0);
}

.cart-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
}

.cart-header h3 {
    font-size: 1.25rem;
    font-weight: 500;
}

.cart-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

.cart-close:hover {
    color: var(--color-text-primary);
}

.cart-items {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-lg);
}

.cart-empty {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 200px;
    color: var(--color-text-tertiary);
}

.cart-item {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-md);
}

.cart-item-info {
    flex: 1;
}

.cart-item-title {
    font-size: 0.9375rem;
    font-weight: 500;
    margin-bottom: var(--space-xs);
    line-height: 1.3;
}

.cart-item-category {
    font-size: 0.75rem;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.cart-item-price {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    font-weight: 500;
    white-space: nowrap;
}

.cart-item-remove {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    color: var(--color-text-tertiary);
    transition: color var(--transition-fast);
    align-self: flex-start;
}

.cart-item-remove:hover {
    color: var(--color-error);
}

.cart-footer {
    padding: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.cart-total {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-lg);
    font-size: 1.125rem;
}

.cart-total span:last-child {
    font-family: var(--font-serif);
    font-size: 1.5rem;
    font-weight: 500;
}

.cart-secure {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    margin-top: var(--space-md);
    font-size: 0.8125rem;
    color: var(--color-text-tertiary);
}

/* ============================================
   Modal
   ============================================ */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.8);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 1200;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.95);
    width: 94%;
    max-width: 720px;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 1201;
}

@media (max-width: 768px) {
    .modal {
        max-height: 85vh;
        overflow-y: auto;
    }
}

.modal.active {
    opacity: 1;
    visibility: visible;
    transform: translate(-50%, -50%) scale(1);
}

.modal-close {
    position: absolute;
    top: var(--space-md);
    right: var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
    z-index: 1;
}

.modal-close:hover {
    color: var(--color-text-primary);
}

.modal-content {
    padding: var(--space-xl) var(--space-2xl);
}

.modal-category {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 28px;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-accent);
    background: var(--color-accent-light);
    padding: 0 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-accent-muted);
}

.modal-title {
    font-size: 1.5rem;
    margin-bottom: var(--space-md);
}

.modal-description {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-lg);
}

.modal-specs {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-sm);
    padding: var(--space-lg);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-lg);
}

.modal-spec {
    text-align: center;
}

.modal-spec-value {
    display: block;
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--color-text-primary);
    margin-bottom: 2px;
}

.modal-spec-label {
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.modal-features {
    margin-bottom: var(--space-lg);
}

.modal-features h4 {
    font-family: var(--font-sans);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-md);
}

.modal-features ul.features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px 20px;
}

.modal-features li {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

.modal-features li svg {
    flex-shrink: 0;
    color: var(--color-success);
}

.modal-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
}

.modal-price {
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 500;
}

/* ============================================
   Success Page Styles
   ============================================ */
.success-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-xl);
}

.success-content {
    text-align: center;
    max-width: 500px;
}

.success-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-xl);
    background: rgba(63, 185, 80, 0.15);
    border-radius: 50%;
    color: var(--color-success);
    animation: scaleIn 0.5s ease forwards;
}

.success-title {
    font-size: 2rem;
    margin-bottom: var(--space-md);
}

.success-message {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-2xl);
}

.download-list {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    margin-bottom: var(--space-2xl);
    text-align: left;
}

.download-list h3 {
    font-size: 1rem;
    margin-bottom: var(--space-md);
}

.download-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-sm);
}

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

.download-item-name {
    font-size: 0.9375rem;
    font-weight: 500;
}

@keyframes scaleIn {
    from {
        transform: scale(0);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

/* ============================================
   Loading States
   ============================================ */
.loading {
    position: relative;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: inherit;
    border-radius: inherit;
}

.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--color-border);
    border-top-color: var(--color-accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================
   Utilities
   ============================================ */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-bg-elevated);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-tertiary);
}