/* =========================================
   1. 全局变量与重置 (Global Variables & Reset)
   ========================================= */
:root {
    /* 品牌色 - 高级深空蓝与活力橙 */
    --color-primary: #0f172a;       /* 深蓝背景 */
    --color-secondary: #1e293b;     /* 次级背景 */
    --color-accent: #f59e0b;        /* 品牌金/橙 */
    --color-accent-hover: #d97706;
    --color-text-main: #f8fafc;     /* 主要文字 */
    --color-text-muted: #94a3b8;    /* 次要文字 */
    
    /* 字体 */
    --font-family: 'Helvetica Neue', Helvetica, 'PingFang SC', 'Microsoft YaHei', Arial, sans-serif;
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;

    /* 动画 */
    --transition-speed: 0.3s;
    --border-radius: 8px;
}

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

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

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

ul {
    list-style: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
    position: relative;
    z-index: 2;
}

/* =========================================
   2. 通用组件 (Components)
   ========================================= */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-speed);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.9rem;
}

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

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

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

.btn-outline:hover {
    background-color: var(--color-text-main);
    color: var(--color-primary);
    transform: translateY(-2px);
}

.section {
    padding: var(--spacing-xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    background: linear-gradient(to right, #fff, #94a3b8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-desc {
    color: var(--color-text-muted);
    font-size: 1.1rem;
}

/* =========================================
   3. 导航栏 (Header)
   ========================================= */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: var(--spacing-sm) 0;
    z-index: 1000;
    transition: background-color var(--transition-speed), padding var(--transition-speed);
}

.header.scrolled {
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    padding: var(--spacing-xs) 0;
    box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: 2px;
}

.nav-list {
    display: flex;
    gap: var(--spacing-md);
}

.nav-list a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-text-main);
    position: relative;
}

.nav-list a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-accent);
    transition: width var(--transition-speed);
}

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

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background-color: var(--color-text-main);
    transition: all 0.3s;
}

/* =========================================
   4. Hero 区域 (Hero Section)
   ========================================= */
.hero {
    height: 100vh;
    min-height: 600px;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: 80px; /* Offset for fixed header */
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    /* 使用 Unsplash 影视相关图片 */
    background-image: linear-gradient(to bottom, rgba(15, 23, 42, 0.7), rgba(15, 23, 42, 0.9)), url('https://images.unsplash.com/photo-1536440136628-849c177e76a1?ixlib=rb-1.2.1&auto=format&fit=crop&w=1920&q=80');
    background-size: cover;
    background-position: center;
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 800px;
}

.hero-title {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
    font-weight: 800;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-lg);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* 插画风格装饰形状 */
.illustration-shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    z-index: 1;
    opacity: 0.6;
}

.shape-1 {
    width: 300px;
    height: 300px;
    background: var(--color-accent);
    top: 20%;
    left: -100px;
    animation: float 6s ease-in-out infinite;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: #4f46e5; /* Indigo */
    bottom: 10%;
    right: -150px;
    animation: float 8s ease-in-out infinite reverse;
}

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

/* =========================================
   5. 服务模块 (Services)
   ========================================= */
.services {
    background-color: var(--color-secondary);
    position: relative;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.service-card {
    background: rgba(255, 255, 255, 0.03);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: transform var(--transition-speed), background var(--transition-speed);
    text-align: center;
}

.service-card:hover {
    transform: translateY(-10px);
    background: rgba(255, 255, 255, 0.06);
    border-color: var(--color-accent);
}

.service-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
    display: block;
}

.service-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-xs);
    color: var(--color-text-main);
}

.service-card p {
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

/* =========================================
   6. 案例模块 (Portfolio)
   ========================================= */
.portfolio {
    background-color: var(--color-primary);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: var(--spacing-sm);
}

.portfolio-item {
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    aspect-ratio: 16/9;
    cursor: pointer;
    group: 'portfolio';
}

.portfolio-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.portfolio-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: var(--spacing-md);
    opacity: 0;
    transition: opacity var(--transition-speed);
}

.portfolio-item:hover .portfolio-img {
    transform: scale(1.1);
}

.portfolio-item:hover .portfolio-overlay {
    opacity: 1;
}

.portfolio-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #fff;
    transform: translateY(20px);
    transition: transform var(--transition-speed);
}

.portfolio-category {
    font-size: 0.9rem;
    color: var(--color-accent);
    margin-bottom: 5px;
    transform: translateY(20px);
    transition: transform var(--transition-speed) 0.1s;
}

.portfolio-item:hover .portfolio-title,
.portfolio-item:hover .portfolio-category {
    transform: translateY(0);
}

/* =========================================
   7. 联系 CTA (Contact CTA)
   ========================================= */
.contact-cta {
    background: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-primary) 100%);
    text-align: center;
    border-top: 1px solid rgba(255,255,255,0.05);
}

.contact-cta h2 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.contact-cta p {
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
}

/* =========================================
   8. 页脚 (Footer)
   ========================================= */
.footer {
    background-color: #020617;
    padding: var(--spacing-lg) 0 var(--spacing-md);
    border-top: 1px solid rgba(255,255,255,0.05);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.footer-info h3 {
    color: var(--color-accent);
    margin-bottom: var(--spacing-sm);
}

.footer-info p {
    color: var(--color-text-muted);
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.footer-copyright {
    text-align: right;
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

/* =========================================
   9. 动画类 (Animations)
   ========================================= */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* =========================================
   10. 响应式适配 (Media Queries)
   ========================================= */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }

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

    .nav-list {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background-color: var(--color-secondary);
        flex-direction: column;
        padding: var(--spacing-md);
        gap: var(--spacing-sm);
        transform: translateY(-150%);
        transition: transform 0.3s ease-in-out;
        box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    }

    .nav-list.active {
        transform: translateY(0);
    }

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

    .footer-copyright {
        text-align: center;
        margin-top: var(--spacing-sm);
    }
}