/* ========================================
   筋斗云学院 - 样式表
   现代简约科技感 + 活泼有趣
   ======================================== */

/* CSS Variables */
:root {
    /* Primary Colors - 活泼的蓝紫渐变 */
    --color-primary: #6366f1;
    --color-primary-dark: #4f46e5;
    --color-primary-light: #818cf8;
    --color-secondary: #a855f7;
    --color-accent: #f59e0b;
    --color-accent-light: #fbbf24;
    --color-success: #10b981;

    /* Gradient */
    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
    --gradient-hero: linear-gradient(135deg, #e0e7ff 0%, #f3e8ff 50%, #fce7f3 100%);
    --gradient-text: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);

    /* Background Colors - Light Theme */
    --bg-primary: #fafafa;
    --bg-secondary: #f5f5f5;
    --bg-card: #ffffff;
    --bg-card-hover: #f9f9f9;

    /* Text Colors - Light Theme */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-muted: #9ca3af;

    /* Border - Light Theme */
    --border-color: rgba(0, 0, 0, 0.08);
    --border-radius: 16px;
    --border-radius-sm: 8px;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    /* Typography */
    --font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;
    --font-size-4xl: 3rem;
    --font-size-5xl: 4rem;

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* Shadows - Light Theme */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.1);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.15);

    /* Container */
    --container-max: 1200px;
    --container-padding: 1.5rem;
}

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

html {
    scroll-behavior: smooth;
}

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

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

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

ul {
    list-style: none;
}

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

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

/* ========================================
   Navigation
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--spacing-sm) 0;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition-normal);
}

.navbar.scrolled {
    padding: var(--spacing-xs) 0;
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-sm);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: var(--font-size-xl);
    font-weight: 700;
}

.logo img {
    width: 40px;
    height: 40px;
}

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

.nav-links a {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
    padding: var(--spacing-xs) 0;
}

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

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

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

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: relative;
    padding: var(--spacing-2xl) var(--spacing-md);
    overflow: hidden;
}

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

/* Animated Clouds */
.cloud {
    position: absolute;
    background: radial-gradient(ellipse at center, rgba(99, 102, 241, 0.08) 0%, transparent 70%);
    border-radius: 50%;
    animation: float 20s ease-in-out infinite;
}

.cloud-1 {
    width: 600px;
    height: 200px;
    top: 10%;
    left: -10%;
    animation-delay: 0s;
}

.cloud-2 {
    width: 400px;
    height: 150px;
    top: 40%;
    right: -5%;
    animation-delay: -7s;
}

.cloud-3 {
    width: 500px;
    height: 180px;
    bottom: 20%;
    left: 20%;
    animation-delay: -14s;
}

@keyframes float {
    0%, 100% {
        transform: translateX(0) translateY(0);
    }
    25% {
        transform: translateX(30px) translateY(-20px);
    }
    50% {
        transform: translateX(-20px) translateY(10px);
    }
    75% {
        transform: translateX(20px) translateY(-10px);
    }
}

/* Gradient Orbs */
.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.5;
    animation: pulse 10s ease-in-out infinite;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: var(--color-primary);
    top: -200px;
    right: -200px;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: var(--color-secondary);
    bottom: -100px;
    left: -100px;
    animation-delay: -5s;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.2);
        opacity: 0.3;
    }
}

/* Hero Content */
.hero-content {
    text-align: center;
    max-width: 800px;
    z-index: 1;
}

.hero-logo {
    margin-bottom: var(--spacing-lg);
    animation: float-logo 6s ease-in-out infinite;
}

.hero-logo img {
    width: 120px;
    height: 120px;
    margin: 0 auto;
    filter: drop-shadow(0 0 30px rgba(99, 102, 241, 0.5));
}

@keyframes float-logo {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

.hero-title {
    font-size: clamp(var(--font-size-3xl), 8vw, var(--font-size-5xl));
    font-weight: 900;
    margin-bottom: var(--spacing-sm);
    line-height: 1.1;
}

.gradient-text {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-slogan {
    font-size: clamp(var(--font-size-xl), 4vw, var(--font-size-3xl));
    font-weight: 300;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    letter-spacing: 0.1em;
}

.hero-desc {
    font-size: var(--font-size-lg);
    color: var(--text-muted);
    margin-bottom: var(--spacing-xl);
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: var(--font-size-base);
    font-weight: 600;
    border-radius: 50px;
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--text-primary);
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.6);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover {
    border-color: var(--color-primary);
    background: rgba(99, 102, 241, 0.1);
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-muted);
    font-size: var(--font-size-xs);
    animation: bounce 2s infinite;
}

.mouse {
    width: 24px;
    height: 36px;
    border: 2px solid var(--text-secondary);
    border-radius: 12px;
    position: relative;
}

.mouse::before {
    content: '';
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 4px;
    background: var(--text-secondary);
    border-radius: 50%;
    animation: scroll-wheel 2s infinite;
}

@keyframes scroll-wheel {
    0% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(12px);
    }
}

@keyframes bounce {
    0%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(-10px);
    }
}

/* ========================================
   Section Styles
   ======================================== */
section {
    padding: var(--spacing-2xl) 0;
    position: relative;
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--spacing-2xl);
}

.section-tag {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(99, 102, 241, 0.08);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: 50px;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-primary-dark);
    margin-bottom: var(--spacing-md);
}

.section-title {
    font-size: clamp(var(--font-size-2xl), 5vw, var(--font-size-3xl));
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    line-height: 1.3;
}

.section-desc {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
}

/* ========================================
   Courses Section
   ======================================== */
.courses {
    background: var(--bg-secondary);
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
}

.course-card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: var(--transition-normal);
}

.course-card:hover {
    transform: translateY(-8px);
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: var(--shadow-glow);
}

.course-card.disabled {
    opacity: 0.6;
    background: var(--bg-secondary);
    cursor: not-allowed;
}

.course-card.disabled:hover {
    transform: none;
    border-color: var(--border-color);
    box-shadow: none;
}

.course-card.disabled .course-content h3 {
    color: var(--text-muted);
}

.course-card.disabled .course-content p {
    color: var(--text-muted);
}

.course-card.disabled .course-overlay {
    background: linear-gradient(135deg, rgba(148, 163, 184, 0.08), rgba(100, 116, 139, 0.08));
}

.course-card.disabled .course-number {
    color: var(--text-muted);
}

.course-thumbnail {
    position: relative;
    padding: var(--spacing-md);
    padding-bottom: 0;
}

.course-thumbnail img {
    width: 100%;
    height: auto;
    object-fit: cover;
    transition: var(--transition-slow);
}

.course-card:hover .course-thumbnail img {
    transform: scale(1.05);
}

.course-overlay {
    position: relative;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(168, 85, 247, 0.08));
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
}

.course-number {
    font-size: 2.5rem;
    font-weight: 900;
    color: var(--color-primary);
    opacity: 0.7;
    line-height: 1;
}

.course-content {
    padding: var(--spacing-md);
}

.course-content h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.course-content p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.6;
}

.course-link {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-primary-light);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.course-link:hover {
    color: var(--color-accent);
}

/* ========================================
   Course Tools Section
   ======================================== */
.course-tools-section {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.course-tools-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.course-tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.course-tool-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-md);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    transition: var(--transition-normal);
}

.course-tool-card:hover {
    border-color: rgba(99, 102, 241, 0.3);
    transform: translateY(-4px);
}

.course-tool-icon {
    width: 48px;
    height: 48px;
    background: var(--bg-secondary);
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
}

.course-tool-info {
    flex: 1;
    min-width: 0;
}

.course-tool-info h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.course-tool-links {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-xs);
    flex-wrap: wrap;
}

.course-tool-links .tool-link {
    font-size: var(--font-size-xs);
    padding: 4px 12px;
    background: var(--gradient-primary);
    border-radius: 20px;
    color: var(--text-primary);
    font-weight: 500;
}

.course-tool-links .tool-link.docs {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.course-tool-links .tool-link.docs:hover {
    border-color: var(--color-primary);
    color: var(--text-primary);
}

.course-tool-code {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: var(--font-size-xs);
}

.code-label {
    color: var(--text-muted);
}

.code-value {
    color: var(--color-accent);
    font-family: monospace;
    font-weight: 500;
}

.copy-code-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 4px;
    margin-left: 4px;
    border-radius: 4px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.copy-code-btn:hover {
    color: var(--color-primary);
    background: rgba(99, 102, 241, 0.1);
}

.copy-code-btn svg {
    width: 14px;
    height: 14px;
}

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

.code-benefit {
    font-size: var(--font-size-xs);
    color: var(--color-primary);
    margin-top: 4px;
    font-weight: 500;
}

/* ========================================
   Tools Section
   ======================================== */
.tools-filter {
    margin-bottom: var(--spacing-xl);
}

.filter-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm);
}

.filter-btn {
    padding: var(--spacing-xs) var(--spacing-md);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50px;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: var(--transition-fast);
}

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

.filter-btn.active {
    background: var(--gradient-primary);
    border-color: transparent;
    color: var(--text-primary);
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-md);
    transition: var(--transition-normal);
}

.tool-card:hover {
    border-color: rgba(99, 102, 241, 0.3);
    background: var(--bg-card-hover);
    transform: translateY(-4px);
}

.tool-card.hidden {
    display: none;
}

/* Tool Cards Filter Animation */
.tool-card {
    animation: fadeInScale 0.4s ease forwards;
}

.tool-card.filtering-out {
    animation: fadeOutScale 0.3s ease forwards;
}

@keyframes fadeInScale {
    0% {
        opacity: 0;
        transform: scale(0.9) translateY(10px);
    }
    50% {
        opacity: 0.5;
        transform: scale(0.95) translateY(5px);
    }
    100% {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

@keyframes fadeOutScale {
    0% {
        opacity: 1;
        transform: scale(1);
    }
    100% {
        opacity: 0;
        transform: scale(0.9);
    }
}

.tool-icon {
    width: 48px;
    height: 48px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.tool-icon img {
    width: 28px;
    height: 28px;
    filter: none;
    object-fit: contain;
}

.emoji-icon {
    font-size: 28px;
    line-height: 1;
}

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

.tool-info {
    flex: 1;
    min-width: 0;
}

.tool-info h3 {
    font-size: var(--font-size-base);
    font-weight: 600;
    margin-bottom: 4px;
}

.tool-info p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    line-height: 1.5;
}

.tool-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tool-link {
    font-size: var(--font-size-xs);
    padding: 4px 12px;
    background: var(--gradient-primary);
    border-radius: 20px;
    color: var(--text-primary);
    font-weight: 500;
}

.tool-link:hover {
    opacity: 0.9;
}

.invite-code {
    font-size: var(--font-size-xs);
    color: var(--color-accent);
    font-family: monospace;
}

/* ========================================
   Prompts Section
   ======================================== */
.prompts {
    background: var(--bg-secondary);
}

.prompts-filter {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
}

.prompt-filter-btn {
    padding: var(--spacing-xs) var(--spacing-md);
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 50px;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 500;
    transition: var(--transition-fast);
}

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

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

.prompts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-md);
}

.prompt-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: var(--transition-normal);
}

.prompt-card:hover {
    border-color: rgba(99, 102, 241, 0.3);
}

.prompt-card.hidden {
    display: none;
}

.prompt-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    background: rgba(99, 102, 241, 0.04);
    border-bottom: 1px solid var(--border-color);
}

.prompt-tag {
    font-size: var(--font-size-xs);
    padding: 4px 10px;
    background: var(--gradient-primary);
    border-radius: 20px;
    font-weight: 500;
}

.copy-btn {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    padding: 4px 10px;
    border-radius: 20px;
    transition: var(--transition-fast);
}

.copy-btn:hover {
    background: rgba(99, 102, 241, 0.1);
    color: var(--text-primary);
}

.copy-btn svg {
    width: 14px;
    height: 14px;
}

.prompt-card h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    padding: var(--spacing-sm) var(--spacing-md);
    padding-bottom: 0;
}

.prompt-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    padding: var(--spacing-xs) var(--spacing-md);
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.prompt-result {
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: var(--bg-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.prompt-result img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.prompt-emoji {
    font-size: 4rem;
}

/* ========================================
   Policy Section
   ======================================== */
.policy-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.policy-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: var(--transition-normal);
}

.policy-card:hover {
    border-color: rgba(99, 102, 241, 0.3);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.policy-header {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-card) 100%);
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.policy-platform {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.platform-icon {
    font-size: 1.5rem;
}

.policy-platform h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin: 0;
    color: var(--text-primary);
}

.policy-badge {
    background: rgba(99, 102, 241, 0.1);
    color: var(--color-primary);
    font-size: var(--font-size-xs);
    font-weight: 500;
    padding: 4px 10px;
    border-radius: 20px;
    white-space: nowrap;
}

.policy-content {
    padding: var(--spacing-lg);
}

.policy-time {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px dashed var(--border-color);
}

.policy-items {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.policy-item h4 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.policy-item p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.6;
}

.policy-item ul {
    margin: 0;
    padding-left: 0;
    list-style: none;
}

.policy-item li {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    padding: var(--spacing-xs) 0;
    padding-left: var(--spacing-md);
    position: relative;
    line-height: 1.5;
}

.policy-item li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--color-primary);
}

.policy-table {
    width: 100%;
    border-collapse: collapse;
    font-size: var(--font-size-xs);
    margin-top: var(--spacing-sm);
}

.policy-table th,
.policy-table td {
    padding: 8px 6px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.policy-table th {
    background: var(--bg-secondary);
    font-weight: 600;
    color: var(--text-primary);
}

.policy-table td {
    color: var(--text-secondary);
}

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

.policy-link {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-primary-light);
}

.policy-link:hover {
    color: var(--color-accent);
}

.policy-notice {
    background: rgba(245, 158, 11, 0.08);
    border: 1px solid rgba(245, 158, 11, 0.25);
    border-radius: var(--border-radius);
    padding: var(--spacing-md) var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.policy-notice p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin: 0;
}

.notice-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.notice-content h4 {
    font-size: var(--font-size-base);
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--color-accent);
}

.notice-content p {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========================================
   About Section
   ======================================== */
.about {
    background: var(--bg-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: center;
}

.about-text .section-tag {
    margin-bottom: var(--spacing-sm);
}

.about-text h2 {
    font-size: clamp(var(--font-size-2xl), 4vw, var(--font-size-3xl));
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    line-height: 1.3;
}

.about-text p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.about-stats {
    display: flex;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: var(--font-size-3xl);
    font-weight: 900;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.about-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.about-card {
    width: 300px;
    height: 300px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.about-card::before {
    content: '';
    position: absolute;
    inset: -2px;
    background: var(--gradient-primary);
    border-radius: var(--border-radius);
    z-index: -1;
    opacity: 0.5;
    filter: blur(20px);
}

.floating-icons {
    position: relative;
    width: 100%;
    height: 100%;
}

.float-icon {
    position: absolute;
    font-size: 3rem;
    animation: float-icon 6s ease-in-out infinite;
}

.float-icon:nth-child(1) {
    top: 20%;
    left: 20%;
    animation-delay: 0s;
}

.float-icon:nth-child(2) {
    top: 20%;
    right: 20%;
    animation-delay: -1.5s;
}

.float-icon:nth-child(3) {
    bottom: 20%;
    left: 20%;
    animation-delay: -3s;
}

.float-icon:nth-child(4) {
    bottom: 20%;
    right: 20%;
    animation-delay: -4.5s;
}

@keyframes float-icon {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-15px) rotate(5deg);
    }
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

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

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: var(--font-size-xl);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.footer-logo img {
    width: 36px;
    height: 36px;
}

.footer-tagline {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
}

.social-links {
    display: flex;
    gap: var(--spacing-sm);
}

.social-link {
    width: 40px;
    height: 40px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.social-link:hover {
    background: var(--gradient-primary);
    border-color: transparent;
    color: var(--text-primary);
    transform: translateY(-2px);
}

.social-link svg {
    width: 18px;
    height: 18px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.footer-column h4 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.footer-column li {
    margin-bottom: var(--spacing-xs);
}

.footer-column a {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

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

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

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

/* ========================================
   Toast Notification
   ======================================== */
.toast {
    position: fixed;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 50px;
    padding: var(--spacing-sm) var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    box-shadow: var(--shadow-lg);
    z-index: 9999;
    opacity: 0;
    transition: all 0.3s ease;
}

.toast-message {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--bg-primary);
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.toast-icon {
    width: 24px;
    height: 24px;
    background: var(--bg-primary);
    color: var(--text-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
}

/* ========================================
   Animations
   ======================================== */
[data-aos] {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos].aos-animate {
    opacity: 1;
    transform: translateY(0);
}

[data-aos="fade-right"] {
    transform: translateX(-30px);
}

[data-aos="fade-right"].aos-animate {
    transform: translateX(0);
}

[data-aos="fade-left"] {
    transform: translateX(30px);
}

[data-aos="fade-left"].aos-animate {
    transform: translateX(0);
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 968px) {
    .nav-links {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

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

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

    .footer-brand {
        flex-direction: column;
        align-items: center;
    }

    .social-links {
        justify-content: center;
    }

    .footer-links {
        text-align: left;
    }
}

@media (max-width: 640px) {
    :root {
        --container-padding: 1rem;
    }

    .hero-cta {
        flex-direction: column;
        width: 100%;
        max-width: 280px;
    }

    .btn {
        width: 100%;
    }

    .courses-grid,
    .tools-grid,
    .prompts-grid,
    .policy-grid {
        grid-template-columns: 1fr;
    }

    .about-stats {
        flex-direction: column;
        gap: var(--spacing-md);
    }

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

    .filter-tags,
    .prompts-filter {
        justify-content: flex-start;
        overflow-x: auto;
        padding-bottom: var(--spacing-xs);
        -webkit-overflow-scrolling: touch;
    }
}

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

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

::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}

/* ========================================
   Selection
   ======================================== */
::selection {
    background: var(--color-primary);
    color: var(--text-primary);
}