/* 全局重置与基础 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: #f8f9fc;
    color: #1a1a2e;
    transition: background 0.3s, color 0.3s;
    line-height: 1.6;
}

body.dark {
    background: #0f0f1a;
    color: #e0e0e0;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

:root {
    --primary: #1a1a2e;
    --secondary: #f0c040;
    --accent: #e94560;
    --bg: #f8f9fc;
    --text: #1a1a2e;
    --glass: rgba(255, 255, 255, 0.25);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    --radius: 20px;
    --transition: 0.3s ease;
}

body.dark {
    --primary: #e0e0e0;
    --secondary: #f0c040;
    --accent: #ff6b6b;
    --bg: #0f0f1a;
    --text: #e0e0e0;
    --glass: rgba(255, 255, 255, 0.08);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

/* 头部导航 */
header {
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding: 0 20px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: background 0.3s;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.header-logo svg {
    width: 40px;
    height: 40px;
    flex-shrink: 0;
}

.header-logo span {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #f0c040, #e94560);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-menu {
    display: flex;
    gap: 8px;
    align-items: center;
    flex-wrap: wrap;
}

.nav-menu a {
    padding: 8px 16px;
    border-radius: 30px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s;
    color: var(--text);
}

.nav-menu a:hover,
.nav-menu a.active {
    background: var(--secondary);
    color: #1a1a2e;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    background: none;
    border: none;
    padding: 5px;
}

.menu-toggle span {
    display: block;
    width: 28px;
    height: 3px;
    background: var(--text);
    border-radius: 3px;
    transition: all 0.3s;
}

.dark-toggle {
    background: var(--glass);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 30px;
    padding: 8px 16px;
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--text);
    transition: all 0.3s;
    backdrop-filter: blur(10px);
}

.dark-toggle:hover {
    background: var(--secondary);
    color: #1a1a2e;
}

.search-box {
    display: flex;
    align-items: center;
    background: var(--glass);
    border-radius: 30px;
    padding: 5px 15px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.search-box input {
    background: transparent;
    border: none;
    outline: none;
    color: var(--text);
    padding: 8px 0;
    width: 160px;
    font-size: 0.9rem;
}

.search-box input::placeholder {
    color: var(--text);
    opacity: 0.6;
}

.search-box button {
    background: transparent;
    border: none;
    cursor: pointer;
    color: var(--text);
    padding: 5px;
}

/* Banner 横幅 */
.banner {
    position: relative;
    overflow: hidden;
    height: 100vh;
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 70px;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
}

.banner-slide {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 1s ease;
    padding: 40px;
}

.banner-slide.active {
    opacity: 1;
}

.banner-content {
    text-align: center;
    color: #fff;
    max-width: 800px;
    z-index: 2;
}

.banner-content h1 {
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.2;
    background: linear-gradient(135deg, #f0c040, #e94560);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.banner-content p {
    font-size: 1.3rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.banner-content .btn {
    display: inline-block;
    padding: 15px 40px;
    background: var(--secondary);
    color: #1a1a2e;
    border-radius: 50px;
    font-weight: 700;
    font-size: 1.1rem;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.banner-content .btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(240, 192, 64, 0.4);
}

.banner-nav {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 3;
}

.banner-nav button {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 2px solid rgba(255, 255, 255, 0.6);
    background: transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.banner-nav button.active {
    background: var(--secondary);
    border-color: var(--secondary);
}

/* 通用区块 */
section {
    padding: 80px 0;
}

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

.section-title h2 {
    font-size: 2.6rem;
    font-weight: 700;
    margin-bottom: 16px;
    background: linear-gradient(135deg, #f0c040, #e94560);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-title p {
    font-size: 1.1rem;
    opacity: 0.8;
    max-width: 600px;
    margin: 0 auto;
}

/* 毛玻璃卡片 */
.glass-card {
    background: var(--glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: var(--radius);
    padding: 40px;
    box-shadow: var(--shadow);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s;
}

.glass-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

/* 网格布局 */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

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

.mt-20 {
    margin-top: 20px;
}

.mb-20 {
    margin-bottom: 20px;
}

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

.gap-10 {
    gap: 10px;
}

/* 滚动动画 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

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

/* 数字统计 */
.stat-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--secondary);
}

.stat-label {
    font-size: 1rem;
    opacity: 0.8;
    margin-top: 8px;
}

/* FAQ 手风琴 */
.accordion-item {
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding: 16px 0;
}

.accordion-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-weight: 600;
    font-size: 1.1rem;
}

.accordion-body {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
    padding-top: 0;
}

.accordion-body.open {
    max-height: 500px;
    padding-top: 16px;
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--secondary);
    color: #1a1a2e;
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    box-shadow: 0 4px 20px rgba(240, 192, 64, 0.3);
    transition: all 0.3s;
    z-index: 999;
    display: none;
    align-items: center;
    justify-content: center;
}

.back-to-top.show {
    display: flex;
}

.back-to-top:hover {
    transform: scale(1.1);
}

/* 页脚 */
footer {
    background: var(--primary);
    color: #fff;
    padding: 60px 0 30px;
    margin-top: 40px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
}

.footer-grid h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--secondary);
}

.footer-grid a {
    display: block;
    padding: 6px 0;
    opacity: 0.8;
    transition: all 0.3s;
}

.footer-grid a:hover {
    opacity: 1;
    color: var(--secondary);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 40px;
    padding-top: 20px;
    text-align: center;
    font-size: 0.9rem;
    opacity: 0.7;
}

/* 面包屑 */
.breadcrumb {
    display: flex;
    gap: 8px;
    padding: 10px 0;
    font-size: 0.9rem;
    opacity: 0.7;
    flex-wrap: wrap;
}

.breadcrumb a:hover {
    color: var(--secondary);
}

/* 响应式布局 */
@media (max-width: 1024px) {
    .grid-2,
    .grid-3,
    .grid-4,
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }

    .banner-content h1 {
        font-size: 3rem;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--glass);
        backdrop-filter: blur(30px);
        padding: 20px;
        border-radius: 0 0 20px 20px;
        gap: 12px;
    }

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

    .menu-toggle {
        display: flex;
    }

    .search-box input {
        width: 100px;
    }

    .banner-content h1 {
        font-size: 2.4rem;
    }

    .banner-content p {
        font-size: 1rem;
    }

    .grid-2,
    .grid-3,
    .grid-4,
    .footer-grid {
        grid-template-columns: 1fr;
    }

    section {
        padding: 50px 0;
    }

    .section-title h2 {
        font-size: 2rem;
    }

    .stat-number {
        font-size: 2.2rem;
    }
}

@media (max-width: 480px) {
    .banner-content h1 {
        font-size: 1.8rem;
    }

    .header-logo span {
        font-size: 1.2rem;
    }

    .container {
        padding: 0 12px;
    }
}