/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 根变量 - 参考Suno配色方案 */
:root {
    --primary-color: #ff4e4e;
    --secondary-color: #8b5cf6;
    --accent-color: #f59e0b;
    --dark-bg: #0a0a0a;
    --dark-secondary: #1a1a1a;
    --dark-card: #252525;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --gradient-primary: linear-gradient(135deg, #ff4e4e 0%, #8b5cf6 100%);
    --gradient-secondary: linear-gradient(135deg, #8b5cf6 0%, #f59e0b 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    background-color: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* 通用容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏样式 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 24px;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

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

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width 0.3s;
}

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

/* Hero区域 */
.hero {
    margin-top: 70px;
    padding: 100px 20px;
    text-align: center;
    background: radial-gradient(ellipse at center, rgba(139, 92, 246, 0.15) 0%, transparent 70%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 78, 78, 0.1) 0%, transparent 50%);
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero h1 {
    font-size: 56px;
    font-weight: 800;
    margin-bottom: 20px;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto 40px;
}

.cta-button {
    display: inline-block;
    padding: 16px 48px;
    background: var(--gradient-primary);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 18px;
    transition: transform 0.3s, box-shadow 0.3s;
    box-shadow: 0 10px 30px rgba(255, 78, 78, 0.3);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 40px rgba(255, 78, 78, 0.4);
}

/* 教程卡片 */
.tutorial-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    margin-top: 32px;
    padding: 20px 36px;
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.15) 0%, rgba(245, 158, 11, 0.15) 100%);
    border: 1px solid rgba(139, 92, 246, 0.3);
    border-radius: 16px;
    text-decoration: none;
    color: var(--text-primary);
    transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
    max-width: 480px;
    margin-left: auto;
    margin-right: auto;
    cursor: pointer;
}

.tutorial-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent-color);
    box-shadow: 0 12px 36px rgba(139, 92, 246, 0.25);
}

.tutorial-badge {
    display: inline-block;
    padding: 3px 14px;
    font-size: 12px;
    font-weight: 700;
    color: #fff;
    background: var(--gradient-secondary);
    border-radius: 20px;
    letter-spacing: 1px;
}

.tutorial-title {
    font-size: 20px;
    font-weight: 700;
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tutorial-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
    text-align: center;
}

.tutorial-arrow {
    font-size: 14px;
    font-weight: 600;
    color: var(--accent-color);
    transition: letter-spacing 0.3s;
}

.tutorial-card:hover .tutorial-arrow {
    letter-spacing: 2px;
}

@media (max-width: 768px) {
    .tutorial-card {
        padding: 16px 20px;
        max-width: 90%;
    }
    .tutorial-title {
        font-size: 17px;
    }
}

/* 关于部分 */
.about {
    padding: 80px 20px;
    background: var(--dark-secondary);
}

.about h2 {
    font-size: 40px;
    margin-bottom: 30px;
    text-align: center;
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.about p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.8;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

/* 功能特点 */
.features {
    padding: 80px 20px;
}

.features h2 {
    font-size: 40px;
    margin-bottom: 60px;
    text-align: center;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: var(--dark-card);
    padding: 40px 30px;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-color);
    box-shadow: 0 10px 40px rgba(255, 78, 78, 0.2);
}

.feature-card h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: var(--text-primary);
}

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

/* 视频展示区域 */
.videos {
    padding: 80px 20px;
    background: var(--dark-secondary);
}

.videos h2 {
    font-size: 40px;
    margin-bottom: 20px;
    text-align: center;
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    text-align: center;
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 50px;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    max-width: 1200px;
    margin: 0 auto;
}

/* 国内站按钮 */
.domestic-button {
    display: inline-block;
    margin-left: 20px;
    padding: 16px 48px;
    border-radius: 30px;
    background: var(--gradient-secondary);
    color: white;
    text-decoration: none;
    font-weight: 600;
    transition: transform .15s ease, box-shadow .15s ease;
}

.domestic-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(139,92,246,0.18);
}

/* CTA 组合，确保按钮并排且在小屏下换行 */
.cta-group {
    display: inline-flex;
    gap: 14px;
    align-items: center;
}

@media (max-width: 720px) {
    .cta-group {
        gap: 10px;
    }
    .cta-button, .domestic-button {
        padding: 12px 20px;
        font-size: 16px;
    }
}

/* 案例展示 */
.cases {
    padding: 60px 20px;
    background: linear-gradient(180deg, rgba(10,10,10,0.6), rgba(15,15,15,0.6));
}

.cases h2 {
    font-size: 36px;
    margin-bottom: 14px;
    text-align: center;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.case-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    max-width: 1100px;
    margin: 30px auto 0;
}

.case-card {
    display: block;
    text-decoration: none;
    color: var(--text-primary);
    background: var(--dark-card);
    padding: 20px;
    border-radius: 14px;
    border: 1px solid rgba(255,255,255,0.06);
    transition: transform .2s ease, box-shadow .2s ease;
}

.case-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 34px rgba(0,0,0,0.6);
    border-color: rgba(139,92,246,0.18);
}

.case-card h3 {
    font-size: 20px;
    margin-bottom: 8px;
}

.case-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.video-card {
    background: var(--dark-card);
    border-radius: 16px;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(139, 92, 246, 0.3);
}

.video-placeholder {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 宽高比 */
    background: linear-gradient(135deg, rgba(255, 78, 78, 0.2) 0%, rgba(139, 92, 246, 0.2) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-placeholder iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
/* sound controls removed */

/* 使用指南 */
.guide {
    padding: 80px 20px;
}

.guide h2 {
    font-size: 40px;
    margin-bottom: 60px;
    text-align: center;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.guide-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.step {
    position: relative;
    padding: 30px;
    background: var(--dark-card);
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: transform 0.3s;
}

.step:hover {
    transform: translateY(-5px);
}

.step h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.step h4 {
    font-size: 16px;
    margin-bottom: 10px;
    color: var(--accent-color);
}

.step p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* 优势说明 */
.advantages {
    padding: 80px 20px;
    background: var(--dark-secondary);
}

.advantages h2 {
    font-size: 40px;
    margin-bottom: 60px;
    text-align: center;
    background: var(--gradient-secondary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.advantage-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.advantage-item {
    padding: 30px;
    background: var(--dark-card);
    border-radius: 16px;
    border-left: 4px solid var(--primary-color);
    transition: transform 0.3s;
}

.advantage-item:hover {
    transform: translateX(5px);
}

.advantage-item h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.advantage-item p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* FAQ部分 */
.faq {
    padding: 80px 20px;
}

.faq h2 {
    font-size: 40px;
    margin-bottom: 50px;
    text-align: center;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.faq-item {
    max-width: 900px;
    margin: 0 auto 30px;
    padding: 30px;
    background: var(--dark-card);
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: border-color 0.3s;
}

.faq-item:hover {
    border-color: var(--secondary-color);
}

.faq-item h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--text-primary);
}

.faq-item p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* 页脚 */
.footer {
    padding: 40px 20px;
    text-align: center;
    background: var(--dark-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer p {
    color: var(--text-secondary);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        gap: 15px;
        font-size: 14px;
    }

    .hero h1 {
        font-size: 36px;
    }

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

    .about h2,
    .features h2,
    .videos h2,
    .guide h2,
    .advantages h2,
    .faq h2 {
        font-size: 32px;
    }

    .feature-grid,
    .video-grid,
    .guide-steps,
    .advantage-list {
        grid-template-columns: 1fr;
    }

    .cta-button {
        padding: 14px 36px;
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 20px;
    }

    .logo img {
        width: 32px;
        height: 32px;
    }

    .nav-menu {
        gap: 10px;
        font-size: 12px;
    }

    .hero {
        padding: 60px 20px;
    }

    .hero h1 {
        font-size: 28px;
    }
}