/* ============================================
   AS.Tools - Professional Revit Plugin Website
   Design System: Industrial Precision
   ============================================ */

/* CSS Variables */
:root {
    /* Colors */
    --color-bg-primary: #0A1628;
    --color-bg-secondary: #0F2137;
    --color-bg-tertiary: #152642;
    --color-surface: #1A2942;
    --color-surface-hover: #22334D;

    --color-primary: #3B82F6;
    --color-primary-light: #60A5FA;
    --color-primary-dark: #2563EB;

    --color-accent: #06B6D4;
    --color-accent-light: #22D3EE;

    --color-text-primary: #F1F5F9;
    --color-text-secondary: #94A3B8;
    --color-text-muted: #64748B;

    --color-border: rgba(148, 163, 184, 0.1);
    --color-border-hover: rgba(148, 163, 184, 0.2);

    --color-success: #10B981;
    --color-warning: #F59E0B;
    --color-error: #EF4444;

    /* Typography */
    --font-display: 'Manrope', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-body: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, sans-serif;

    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 2rem;
    --text-4xl: 2.5rem;
    --text-5xl: 3.5rem;

    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 24px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.25);
    --shadow-glow: 0 0 60px rgba(59, 130, 246, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* Container */
    --container-max-width: 1200px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img, svg {
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

button, input {
    font-family: inherit;
    border: none;
    outline: none;
}

ul {
    list-style: none;
}

/* Container */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ============================================
   Navigation
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 22, 40, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--space-6);
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-family: var(--font-display);
    font-weight: 700;
    font-size: var(--text-xl);
    color: var(--color-text-primary);
}

.logo-icon {
    width: 40px;
    height: 40px;
    object-fit: contain;
}

.nav-links {
    display: flex;
    gap: var(--space-8);
}

.nav-links a {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--transition-base);
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    cursor: pointer;
    padding: var(--space-2);
}

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

/* ============================================
   Hero Section
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 70px;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    inset: 0;
    z-index: -1;
}

.grid-overlay {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(148, 163, 184, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(148, 163, 184, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 80% 50% at 50% 50%, black 40%, transparent 100%);
}

.gradient-mesh {
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 100%;
    background: radial-gradient(ellipse 60% 50% at 50% 50%, rgba(59, 130, 246, 0.15), transparent 70%);
    filter: blur(60px);
    animation: meshFloat 20s ease-in-out infinite;
}

@keyframes meshFloat {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50% { transform: translate(-5%, 5%) rotate(5deg); }
}

.hero-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: var(--space-20) var(--space-6);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
}

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.2);
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    color: var(--color-primary-light);
    margin-bottom: var(--space-6);
}

.badge-dot {
    width: 6px;
    height: 6px;
    background: var(--color-primary);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-family: var(--font-display);
    font-size: var(--text-5xl);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: var(--space-6);
}

.gradient-text {
    background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-accent-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-8);
    max-width: 500px;
}

.hero-actions {
    display: flex;
    gap: var(--space-4);
    margin-bottom: var(--space-12);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-base);
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.5);
}

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

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

.hero-stats {
    display: flex;
    gap: var(--space-8);
}

.stat {
    text-align: left;
}

.stat-value {
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 700;
    color: var(--color-primary-light);
}

.stat-label {
    font-size: var(--text-sm);
    color: var(--color-text-muted);
    margin-top: var(--space-1);
}

.stat-divider {
    width: 1px;
    background: var(--color-border);
}

/* Hero Visual */
.hero-visual {
    animation: fadeInRight 0.8s ease-out 0.2s both;
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.visual-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-glow);
}

.visual-header {
    display: flex;
    align-items: center;
    padding: var(--space-4);
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg-tertiary);
}

.window-controls {
    display: flex;
    gap: var(--space-2);
    margin-right: var(--space-4);
}

.window-controls span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.window-controls span:nth-child(1) { background: #FF5F57; }
.window-controls span:nth-child(2) { background: #FFBD2E; }
.window-controls span:nth-child(3) { background: #28C840; }

.visual-title {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-text-secondary);
}

.visual-body {
    padding: var(--space-6);
}

/* ============================================
   AI Workflow Display
   ============================================ */

.ai-workflow {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.user-command {
    padding: var(--space-4);
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(6, 182, 212, 0.1) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(59, 130, 246, 0.3);
}

.command-label {
    font-size: var(--text-xs);
    color: var(--color-accent);
    font-weight: 600;
    margin-bottom: var(--space-2);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.command-text {
    font-size: var(--text-sm);
    color: var(--color-text-primary);
    line-height: 1.6;
}

.ai-process {
    padding: var(--space-4);
    background: var(--color-bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
}

.process-label {
    font-size: var(--text-xs);
    color: var(--color-text-secondary);
    font-weight: 600;
    margin-bottom: var(--space-3);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.process-steps {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.process-step {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3);
    background: var(--color-bg-primary);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    opacity: 0;
    transform: translateX(-20px);
    animation: slideIn 0.5s ease-out forwards;
}

.process-step:nth-child(1) {
    animation-delay: 0.3s;
}

.process-step:nth-child(2) {
    animation-delay: 1.0s;
}

.process-step:nth-child(3) {
    animation-delay: 1.7s;
}

.process-step:hover {
    border-color: var(--color-primary);
    background: rgba(59, 130, 246, 0.05);
}

@keyframes slideIn {
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.step-icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-primary);
    border-radius: var(--radius-sm);
    color: white;
}

.step-content {
    flex: 1;
}

.step-text {
    font-size: var(--text-sm);
    color: var(--color-text-primary);
    line-height: 1.5;
}

.workflow-status {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3);
    background: rgba(16, 185, 129, 0.1);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(16, 185, 129, 0.3);
    opacity: 0;
    animation: fadeIn 0.5s ease-out 2.4s forwards;
}

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

.status-icon {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-success);
    border-radius: 50%;
    color: white;
    font-weight: bold;
}

.status-text {
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-success);
}

/* ============================================
   Features Section
   ============================================ */
.features {
    padding: var(--space-20) 0;
    background: var(--color-bg-secondary);
    position: relative;
}

.features::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--color-border), transparent);
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-16);
    animation: fadeIn 0.6s ease-out;
}

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

.section-tag {
    display: inline-block;
    padding: var(--space-2) var(--space-4);
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.2);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-primary-light);
    margin-bottom: var(--space-4);
}

.section-title {
    font-family: var(--font-display);
    font-size: var(--text-4xl);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--space-4);
}

.section-description {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
}

.feature-card {
    position: relative;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: var(--space-8);
    transition: all var(--transition-base);
    animation: fadeInUp 0.6s ease-out both;
}

.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }
.feature-card:nth-child(4) { animation-delay: 0.4s; }
.feature-card:nth-child(5) { animation-delay: 0.5s; }
.feature-card:nth-child(6) { animation-delay: 0.6s; }

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

.feature-card-featured {
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(6, 182, 212, 0.1) 100%);
    border-color: rgba(59, 130, 246, 0.3);
}

.feature-card-featured:hover {
    border-color: rgba(59, 130, 246, 0.5);
    box-shadow: 0 10px 30px rgba(59, 130, 246, 0.2);
}

.featured-badge {
    position: absolute;
    top: var(--space-4);
    right: var(--space-4);
    padding: var(--space-1) var(--space-3);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    color: white;
    font-size: var(--text-xs);
    font-weight: 600;
    border-radius: var(--radius-full);
}

.feature-icon-wrapper {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-5);
    color: var(--color-primary);
}

.feature-icon {
    width: 32px;
    height: 32px;
}

.feature-card h3 {
    font-family: var(--font-display);
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--space-3);
}

.feature-card p {
    font-size: var(--text-base);
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ============================================
   Version Section - Interactive Showcase
   ============================================ */
.version-section {
    padding: var(--space-20) 0;
    background: var(--color-bg-primary);
    overflow: hidden;
}

.version-showcase {
    max-width: 1200px;
    margin: 0 auto;
}

.version-timeline {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: var(--space-8) var(--space-4);
    position: relative;
    margin-bottom: var(--space-12);
}

.version-timeline::before {
    content: '';
    position: absolute;
    top: 50%;
    left: var(--space-8);
    right: var(--space-8);
    height: 2px;
    background: linear-gradient(90deg,
        transparent 0%,
        var(--color-border) 15%,
        var(--color-border) 85%,
        transparent 100%
    );
    z-index: 0;
    transform: translateY(-50%);
}

.version-item {
    position: relative;
    z-index: 1;
    flex-shrink: 0;
    transition: transform var(--transition-slow), z-index 0s;
}

/* Hover effect: card moves up and displays on top */
.version-item:hover {
    transform: translateY(-16px);
    z-index: 100;
}

/* Cards overlap - key to the carousel effect */
.version-item:not(:first-child) {
    margin-left: -30px;
}

.version-card {
    width: 140px;
    height: 170px;
    background: var(--color-surface);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-xl);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
    overflow: hidden;
}

.version-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg,
        rgba(59, 130, 246, 0) 0%,
        rgba(59, 130, 246, 0.05) 100%
    );
    opacity: 0;
    transition: opacity var(--transition-base);
}

.version-item:hover .version-card::before {
    opacity: 1;
}

//* Hover effect: card moves up and displays on top */
.version-item:hover {
    transform: translateY(-16px);
    z-index: 10;
}

.version-year {
    font-family: var(--font-display);
    font-size: var(--text-xs);
    font-weight: 700;
    color: var(--color-text-muted);
    margin-bottom: var(--space-2);
    transition: all 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.version-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-lg);
    transition: all 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
    overflow: visible;
}

.version-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    position: relative;
    z-index: 2;
}

.version-icon::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(135deg,
        var(--color-primary),
        var(--color-accent)
    );
    opacity: 0;
    z-index: 1;
    pointer-events: none;
    transition: opacity var(--transition-base);
}

.version-badge {
    position: absolute;
    top: var(--space-2);
    right: var(--space-2);
    padding: var(--space-1) var(--space-2);
    background: linear-gradient(135deg,
        var(--color-primary) 0%,
        var(--color-accent) 100%
    );
    color: white;
    font-size: 10px;
    font-weight: 700;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    opacity: 1;
}

/* Hover effects for cards */
.version-item:hover .version-card {
    border-color: var(--color-primary);
    box-shadow: 0 16px 60px rgba(59, 130, 246, 0.4);
}

.version-item:hover .version-year {
    color: var(--color-primary);
    font-size: var(--text-lg);
}

.version-item:hover .version-icon {
    background: white;
    transform: scale(1.08);
}

.version-item:hover .version-icon::after {
    opacity: 1;
}

/* .NET 8.0 versions use cyan instead of blue */
.version-item[data-modern="true"] .version-card {
    border-color: rgba(6, 182, 212, 0.3);
}

.version-item[data-modern="true"]:hover .version-card {
    border-color: var(--color-accent);
    box-shadow: 0 16px 60px rgba(6, 182, 212, 0.4);
}

.version-item[data-modern="true"]:hover .version-year {
    color: var(--color-accent);
}

.version-item[data-modern="true"]:hover .version-icon {
    color: var(--color-accent);
}

/* Architecture Labels */
.architecture-labels {
    display: flex;
    justify-content: center;
    gap: var(--space-12);
    margin-bottom: var(--space-12);
}

.arch-label {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}

.arch-label-modern {
    color: var(--color-primary);
}

.arch-dot {
    width: 8px;
    height: 8px;
    background: var(--color-text-muted);
    border-radius: 50%;
}

.arch-label-modern .arch-dot {
    background: var(--color-primary);
}

.arch-range {
    padding: var(--space-1) var(--space-2);
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-sm);
    font-size: var(--text-xs);
}

.badge-new {
    padding: var(--space-1) var(--space-3);
    background: linear-gradient(135deg,
        var(--color-primary) 0%,
        var(--color-accent) 100%
    );
    color: white;
    font-size: 10px;
    font-weight: 700;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    animation: pulse 2s ease-in-out infinite;
}

/* Info Panel */
.version-info-panel {
    padding: var(--space-8);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    text-align: center;
}

.info-panel-content {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--space-12);
}

.info-panel-version,
.info-panel-runtime,
.info-panel-status {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.info-label {
    font-size: var(--text-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.info-value {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--color-text-primary);
    display: flex;
    align-items: center;
    gap: var(--space-2);
    justify-content: center;
    transition: opacity var(--transition-base);
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    position: relative;
}

.status-dot::after {
    content: '';
    position: absolute;
    inset: -2px;
    border-radius: 50%;
    background: inherit;
    opacity: 0.3;
    animation: pulse 2s ease-in-out infinite;
}

.status-active {
    background: var(--color-success);
}

.status-latest {
    background: var(--color-primary);
}

/* ============================================
   Download Section
   ============================================ */
.download-section {
    padding: var(--space-20) 0;
    background: var(--color-bg-secondary);
}

.download-card {
    max-width: 600px;
    margin: 0 auto;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-2xl);
    padding: var(--space-10);
}

.download-header {
    text-align: center;
    margin-bottom: var(--space-8);
}

.download-header h2 {
    font-family: var(--font-display);
    font-size: var(--text-3xl);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--space-3);
}

.download-header p {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
}

/* Captcha Container */
.captcha-container {
    animation: fadeIn 0.5s ease-out;
}

.captcha-label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    margin-bottom: var(--space-6);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
}

.captcha-label svg {
    width: 20px;
    height: 20px;
    color: var(--color-primary);
}

.captcha-prompt {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    margin-bottom: var(--space-5);
    font-size: var(--text-base);
    color: var(--color-text-primary);
}

.math-question {
    font-family: 'SF Mono', 'Monaco', monospace;
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-primary);
    padding: var(--space-2) var(--space-4);
    background: rgba(59, 130, 246, 0.1);
    border-radius: var(--radius-md);
}

.captcha-input-group {
    display: flex;
    gap: var(--space-3);
}

.captcha-input {
    flex: 1;
    padding: var(--space-4);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    color: var(--color-text-primary);
    font-size: var(--text-base);
    transition: border-color var(--transition-fast);
}

.captcha-input:focus {
    outline: none;
    border-color: var(--color-primary);
}

.captcha-input::placeholder {
    color: var(--color-text-muted);
}

.captcha-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-4) var(--space-6);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
    font-family: var(--font-display);
    font-weight: 600;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
}

.captcha-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 14px rgba(59, 130, 246, 0.4);
}

.captcha-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.captcha-error {
    margin-top: var(--space-4);
    font-size: var(--text-sm);
    color: var(--color-error);
    text-align: center;
    display: none;
}

.captcha-error.show {
    display: block;
}

/* Download Result */
.download-result {
    animation: fadeIn 0.5s ease-out;
}

.download-success {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    margin-bottom: var(--space-6);
    color: var(--color-success);
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-lg);
}

.download-success-warning {
    color: var(--color-warning);
    flex-direction: column;
    gap: var(--space-2);
}

.download-success-warning small {
    font-size: var(--text-sm);
    font-weight: 400;
    color: var(--color-text-secondary);
}

.download-success svg {
    width: 32px;
    height: 32px;
}

.download-version {
    text-align: center;
    margin-bottom: var(--space-6);
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
}

.download-version strong {
    color: var(--color-primary);
    font-size: var(--text-2xl);
}

.download-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    width: 100%;
    padding: var(--space-5);
    background: linear-gradient(135deg, var(--color-success) 0%, #059669 100%);
    color: white;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: var(--text-lg);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
    margin-bottom: var(--space-4);
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.4);
}

.download-btn svg {
    width: 24px;
    height: 24px;
}

.file-size {
    font-size: var(--text-sm);
    opacity: 0.9;
}

.remaining-info {
    text-align: center;
    padding: var(--space-3);
    background: rgba(59, 130, 246, 0.1);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
}

.remaining-info strong {
    color: var(--color-primary);
    font-weight: 600;
}

.download-meta {
    text-align: center;
}

.download-meta p {
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

/* Primary Download Links */
.download-links-primary {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    margin-bottom: var(--space-6);
}

/* Backup Download Section */
.backup-section {
    margin-top: var(--space-6);
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border);
}

.backup-section-only {
    border-top: none;
    margin-top: var(--space-4);
}

.backup-header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    margin-bottom: var(--space-4);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    position: relative;
}

.backup-header svg {
    width: 16px;
    height: 16px;
}

.backup-badge {
    margin-left: var(--space-2);
    padding: var(--space-1) var(--space-3);
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    border-radius: var(--radius-full);
    font-size: var(--text-xs);
    color: var(--color-success);
    font-weight: 600;
}

.download-btn-secondary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
}

.download-btn-secondary:hover {
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

/* Baidu Pan Download Button */
.download-btn-baidu {
    background: linear-gradient(135deg, #2932E1 0%, #1E23AA 100%);
}

.download-btn-baidu:hover {
    box-shadow: 0 6px 20px rgba(41, 50, 225, 0.4);
}

/* Baidu Extract Code */
.baidu-extract-code {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    margin-top: var(--space-4);
    padding: var(--space-3) var(--space-4);
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
}

.extract-label {
    color: var(--color-text-secondary);
}

.extract-code {
    font-family: 'SF Mono', 'Monaco', monospace;
    font-size: var(--text-base);
    font-weight: 600;
    color: var(--color-primary);
    background: rgba(59, 130, 246, 0.1);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-sm);
}

.copy-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-1);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--color-text-secondary);
}

.copy-btn:hover {
    background: var(--color-surface-hover);
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.copy-btn.copied {
    color: var(--color-success);
    border-color: var(--color-success);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--color-bg-secondary);
    border-top: 1px solid var(--color-border);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--space-12);
    margin-bottom: var(--space-12);
}

.footer-brand {
    padding-right: var(--space-8);
}

.footer-logo {
    font-family: var(--font-display);
    font-size: var(--text-2xl);
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--space-3);
}

.footer-brand p {
    font-size: var(--text-base);
    color: var(--color-text-secondary);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
}

.footer-link-group h4 {
    font-family: var(--font-display);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: var(--space-4);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-link-group a {
    display: block;
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-3);
    transition: color var(--transition-fast);
}

.footer-link-group a:hover {
    color: var(--color-primary);
}

.footer-bottom {
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--space-4);
}

.footer-bottom p {
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

.footer-beian {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    font-size: var(--text-sm);
}

.footer-beian span {
    color: var(--color-text-muted);
}

.footer-beian a {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

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

.footer-beian img {
    width: 16px;
    height: 16px;
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-description {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-visual {
        display: none;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --text-5xl: 2.5rem;
        --text-4xl: 2rem;
        --text-3xl: 1.75rem;
    }

    .nav-links {
        display: none;
    }

    .nav-menu-btn {
        display: flex;
    }

    .hero-title {
        font-size: var(--text-4xl);
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--space-6);
    }

    .stat-divider {
        display: none;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .version-timeline {
        flex-wrap: wrap;
        gap: var(--space-2);
        padding: var(--space-4);
    }

    .version-timeline::before {
        display: none;
    }

    /* Disable overlap on mobile */
    .version-item:not(:first-child) {
        margin-left: 0;
    }

    /* Disable push effect on mobile */
    .version-item:hover ~ .version-item {
        left: 0;
    }

    .version-card {
        width: 120px;
        height: 150px;
    }

    .version-year {
        font-size: 10px;
    }

    .version-icon {
        width: 48px;
        height: 48px;
        font-size: 24px;
    }

    /* Adjust badge position on tablet */
    .version-badge {
        top: auto;
        bottom: 4px;
        right: 4px;
        font-size: 9px;
    }

    .architecture-labels {
        flex-direction: column;
        gap: var(--space-4);
        align-items: center;
    }

    .info-panel-content {
        flex-direction: column;
        gap: var(--space-6);
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: 1fr;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

    .captcha-input-group {
        flex-direction: column;
    }

    /* AI Workflow responsive */
    .visual-body {
        padding: var(--space-4);
    }

    .process-steps {
        gap: var(--space-2);
    }

    .process-step {
        padding: var(--space-2);
    }

    .step-icon {
        width: 24px;
        height: 24px;
    }

    .step-text {
        font-size: var(--text-xs);
    }

    .hide-mobile {
        display: none;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-4);
    }

    .hero {
        padding-top: 60px;
    }

    .nav-container {
        height: 60px;
    }

    .download-card {
        padding: var(--space-6);
    }

    .version-timeline {
        gap: var(--space-1);
    }

    /* Disable overlap on small mobile */
    .version-item:not(:first-child) {
        margin-left: 0;
    }

    /* Disable push effect on small mobile */
    .version-item:hover ~ .version-item {
        left: 0;
    }

    .version-card {
        width: 110px;
        height: 140px;
    }

    .version-year {
        font-size: 10px;
    }

    .version-icon {
        width: 42px;
        height: 42px;
        font-size: 20px;
    }

    /* Move badge to bottom of card on mobile */
    .version-badge {
        top: auto;
        bottom: 3px;
        right: 3px;
        font-size: 9px;
        padding: 2px 4px;
    }

    .architecture-labels {
        gap: var(--space-3);
    }

    .arch-label {
        font-size: var(--text-xs);
    }

    .info-panel-content {
        gap: var(--space-4);
    }

    .info-value {
        font-size: var(--text-base);
    }
}