/* ==================== 基础设置 ==================== */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #8b5cf6;
    --accent: #22d3ee;
    --dark: #0f172a;
    --darker: #020617;
    --light: #f8fafc;
    --gray: #94a3b8;
    --glass-bg: rgba(255, 255, 255, 0.08);
    --glass-border: rgba(255, 255, 255, 0.15);
    --shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    --radius: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    min-height: 100vh;
    color: var(--light);
    background: var(--darker);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ==================== 动态背景 ==================== */
.bg-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.bg-animation::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: 
        radial-gradient(circle at 20% 80%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(34, 211, 238, 0.1) 0%, transparent 40%);
    animation: bgMove 20s ease-in-out infinite;
}

@keyframes bgMove {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    25% { transform: translate(2%, 2%) rotate(1deg); }
    50% { transform: translate(-1%, 1%) rotate(-1deg); }
    75% { transform: translate(1%, -2%) rotate(0.5deg); }
}

/* 浮动粒子 */
.particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: var(--accent);
    border-radius: 50%;
    opacity: 0.6;
    animation: float 15s infinite;
}

.particle:nth-child(1) { left: 10%; animation-delay: 0s; animation-duration: 20s; }
.particle:nth-child(2) { left: 20%; animation-delay: 2s; animation-duration: 18s; }
.particle:nth-child(3) { left: 30%; animation-delay: 4s; animation-duration: 22s; }
.particle:nth-child(4) { left: 40%; animation-delay: 1s; animation-duration: 19s; }
.particle:nth-child(5) { left: 50%; animation-delay: 3s; animation-duration: 21s; }
.particle:nth-child(6) { left: 60%; animation-delay: 5s; animation-duration: 17s; }
.particle:nth-child(7) { left: 70%; animation-delay: 0.5s; animation-duration: 23s; }
.particle:nth-child(8) { left: 80%; animation-delay: 2.5s; animation-duration: 20s; }
.particle:nth-child(9) { left: 90%; animation-delay: 4.5s; animation-duration: 18s; }

@keyframes float {
    0%, 100% {
        transform: translateY(100vh) scale(0);
        opacity: 0;
    }
    10% { opacity: 0.6; }
    90% { opacity: 0.6; }
    100% {
        transform: translateY(-100vh) scale(1);
        opacity: 0;
    }
}

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 20px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--light), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 8px;
}

.nav-link {
    padding: 10px 20px;
    color: var(--gray);
    text-decoration: none;
    font-weight: 500;
    border-radius: 10px;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover {
    color: var(--light);
    background: var(--glass-bg);
}

.nav-link.active {
    color: var(--accent);
    background: var(--glass-bg);
}

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

/* ==================== Hero 区域 ==================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 24px 80px;
    text-align: center;
}

.hero-content {
    max-width: 900px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 50px;
    font-size: 14px;
    color: var(--accent);
    margin-bottom: 32px;
    animation: fadeInUp 0.8s ease-out;
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: #10b981;
    border-radius: 50%;
    animation: pulse 2s infinite;
}

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

.hero-title {
    font-size: clamp(48px, 10vw, 80px);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fadeInUp 0.8s ease-out 0.1s both;
}

.hero-title .gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent), var(--secondary));
    background-size: 200% 200%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 5s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-description {
    font-size: 20px;
    color: var(--gray);
    max-width: 600px;
    margin: 0 auto 40px;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.8s ease-out 0.3s both;
}

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

/* ==================== 按钮样式 ==================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 16px 32px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    border-radius: 12px;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: var(--glass-bg);
    color: var(--light);
    border: 1px solid var(--glass-border);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-3px);
}

.btn-icon {
    font-size: 20px;
}

/* ==================== 统计卡片 ==================== */
.stats-section {
    padding: 60px 0;
    animation: fadeInUp 0.8s ease-out 0.4s both;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 24px;
}

.stat-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 32px;
    text-align: center;
    transition: var(--transition);
}

.stat-card:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.12);
    box-shadow: var(--shadow);
}

.stat-icon {
    font-size: 40px;
    margin-bottom: 16px;
}

.stat-number {
    font-size: 36px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--light), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
}

.stat-label {
    color: var(--gray);
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ==================== 特性卡片 ==================== */
.features-section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-badge {
    display: inline-block;
    padding: 8px 16px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 50px;
    font-size: 14px;
    color: var(--accent);
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 700;
    margin-bottom: 16px;
}

.section-description {
    color: var(--gray);
    font-size: 18px;
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 32px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow);
    border-color: rgba(255, 255, 255, 0.3);
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: 20px;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.feature-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-description {
    color: var(--gray);
    font-size: 15px;
    line-height: 1.7;
}

/* ==================== 下载页面 ==================== */
.download-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 24px 80px;
}

.download-content {
    max-width: 600px;
    text-align: center;
}

.download-icon {
    width: 120px;
    height: 120px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 60px;
    margin: 0 auto 32px;
    box-shadow: 0 20px 40px rgba(99, 102, 241, 0.4);
    animation: floatIcon 3s ease-in-out infinite;
}

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

.download-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 12px;
}

.download-subtitle {
    font-size: 18px;
    color: var(--gray);
    margin-bottom: 40px;
}

.download-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 40px;
    margin-bottom: 32px;
}

.download-version {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 24px;
}

.download-info {
    margin-bottom: 32px;
}

.download-info-item {
    display: flex;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--glass-border);
}

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

.info-label {
    color: var(--gray);
}

.info-value {
    font-weight: 500;
}

.download-btn-large {
    width: 100%;
    padding: 20px;
    font-size: 18px;
}

.back-link {
    margin-top: 32px;
}

.back-link a {
    color: var(--gray);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
}

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

/* ==================== 404 页面 ==================== */
.error-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 24px 80px;
}

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

.error-code {
    font-size: clamp(120px, 30vw, 200px);
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--secondary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
    margin-bottom: 24px;
    animation: errorPulse 2s ease-in-out infinite;
}

@keyframes errorPulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

.error-title {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 16px;
}

.error-description {
    font-size: 18px;
    color: var(--gray);
    margin-bottom: 40px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.error-illustration {
    font-size: 80px;
    margin-bottom: 32px;
    animation: wobble 2s ease-in-out infinite;
}

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

/* ==================== 页脚 ==================== */
.footer {
    padding: 40px 24px;
    text-align: center;
    border-top: 1px solid var(--glass-border);
    color: var(--gray);
    font-size: 14px;
}

.footer a {
    color: var(--accent);
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 768px) {
    .navbar {
        padding: 16px 20px;
    }

    .nav-links {
        gap: 4px;
    }

    .nav-link {
        padding: 8px 12px;
        font-size: 14px;
    }

    .hero {
        padding: 100px 20px 60px;
    }

    .hero-description {
        font-size: 16px;
    }

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

    .btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }

    .stats-section,
    .features-section {
        padding: 60px 0;
    }

    .download-page,
    .error-page {
        padding: 100px 20px 60px;
    }

    .download-card {
        padding: 24px;
    }

    .download-icon {
        width: 100px;
        height: 100px;
        font-size: 50px;
    }

    .error-illustration {
        font-size: 60px;
    }
}

/* ==================== 加载动画 ==================== */
.page-transition {
    animation: pageIn 0.5s ease-out;
}

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

/* ==================== 工具类 ==================== */
.text-gradient {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}