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

:root {
    --bg-primary: #0b0f1a;
    --bg-secondary: #131826;
    --bg-card: rgba(19, 24, 38, 0.6);
    --text-primary: #e8edf5;
    --text-secondary: #a0aec0;
    --accent: #1a73e8;
    --accent-light: #4a9afa;
    --accent-gradient: linear-gradient(135deg, #1a73e8, #6c5ce7);
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --radius: 16px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 暗色模式支持（默认即为暗色） */
@media (prefers-color-scheme: light) {
    :root {
        --bg-primary: #f0f2f5;
        --bg-secondary: #ffffff;
        --bg-card: rgba(255, 255, 255, 0.8);
        --text-primary: #1a202c;
        --text-secondary: #4a5568;
        --glass-bg: rgba(0, 0, 0, 0.03);
        --glass-border: rgba(0, 0, 0, 0.08);
        --shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    }
}

/* 滚动动画基础 */
section {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.8s ease forwards;
}

section:nth-child(2) { animation-delay: 0.1s; }
section:nth-child(3) { animation-delay: 0.2s; }
section:nth-child(4) { animation-delay: 0.3s; }
section:nth-child(5) { animation-delay: 0.4s; }
section:nth-child(6) { animation-delay: 0.5s; }
section:nth-child(7) { animation-delay: 0.6s; }
section:nth-child(8) { animation-delay: 0.7s; }
section:nth-child(9) { animation-delay: 0.8s; }
section:nth-child(10) { animation-delay: 0.9s; }
section:nth-child(11) { animation-delay: 1s; }
section:nth-child(12) { animation-delay: 1.1s; }
section:nth-child(13) { animation-delay: 1.2s; }
section:nth-child(14) { animation-delay: 1.3s; }
section:nth-child(15) { animation-delay: 1.4s; }
section:nth-child(16) { animation-delay: 1.5s; }
section:nth-child(17) { animation-delay: 1.6s; }
section:nth-child(18) { animation-delay: 1.7s; }

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

/* 头部导航 */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
    padding: 0.75rem 1.5rem;
    transition: var(--transition);
}

header:hover {
    background: rgba(11, 15, 26, 0.9);
}

nav[aria-label="主导航"] ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

nav[aria-label="主导航"] a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: var(--transition);
    position: relative;
}

nav[aria-label="主导航"] a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 60%;
    height: 2px;
    background: var(--accent-gradient);
    transition: transform 0.3s ease;
}

nav[aria-label="主导航"] a:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

nav[aria-label="主导航"] a:hover::after {
    transform: translateX(-50%) scaleX(1);
}

nav[aria-label="主导航"] a[aria-current="page"] {
    color: var(--accent-light);
}

/* 主内容 */
main {
    padding-top: 70px;
    max-width: 1200px;
    margin: 0 auto;
    padding-left: 1.5rem;
    padding-right: 1.5rem;
}

/* 通用section样式 */
section {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: var(--radius);
    border: 1px solid var(--glass-border);
    padding: 2.5rem 2rem;
    margin: 2rem 0;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

section:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
    border-color: var(--accent);
}

/* 标题通用 */
h1, h2, h3 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.8rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: inline-block;
}

h2 {
    font-size: 2rem;
    color: var(--text-primary);
    position: relative;
    padding-bottom: 0.5rem;
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 4px;
    background: var(--accent-gradient);
    border-radius: 2px;
}

h3 {
    font-size: 1.4rem;
    color: var(--text-primary);
}

p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

/* Hero区域 */
#hero {
    text-align: center;
    background: linear-gradient(135deg, rgba(26, 115, 232, 0.15), rgba(108, 92, 231, 0.1)), var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(26, 115, 232, 0.2);
    padding: 4rem 2rem;
    position: relative;
    overflow: hidden;
}

#hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(26, 115, 232, 0.1), transparent 60%);
    animation: heroGlow 8s ease infinite;
}

@keyframes heroGlow {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(5%, 5%); }
}

#hero h1 {
    font-size: 3.2rem;
    margin-bottom: 1rem;
    position: relative;
    z-index: 1;
}

#hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    position: relative;
    z-index: 1;
}

#hero a[role="button"] {
    display: inline-block;
    padding: 1rem 2.5rem;
    background: var(--accent-gradient);
    color: #fff;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: 0 4px 20px rgba(26, 115, 232, 0.4);
    position: relative;
    z-index: 1;
}

#hero a[role="button"]:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 8px 30px rgba(26, 115, 232, 0.6);
}

/* 卡片样式（用于article、blockquote等） */
article, blockquote, details {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-radius: 12px;
    border: 1px solid var(--glass-border);
    padding: 1.5rem;
    margin: 1rem 0;
    transition: var(--transition);
}

article:hover, blockquote:hover, details:hover {
    transform: translateY(-2px);
    border-color: var(--accent);
    box-shadow: 0 4px 20px rgba(26, 115, 232, 0.15);
}

/* 列表样式 */
ul, ol {
    padding-left: 1.5rem;
    color: var(--text-secondary);
}

li {
    margin-bottom: 0.5rem;
}

/* 常见问题 details */
details summary {
    cursor: pointer;
    font-weight: 600;
    color: var(--text-primary);
    padding: 0.5rem 0;
    transition: var(--transition);
}

details summary:hover {
    color: var(--accent-light);
}

details[open] summary {
    color: var(--accent-light);
}

details p {
    margin-top: 0.5rem;
    padding-left: 1rem;
    border-left: 3px solid var(--accent);
}

/* 联系地址 */
address {
    font-style: normal;
    background: var(--glass-bg);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--glass-border);
}

address p {
    margin-bottom: 0.5rem;
}

/* 底部 */
footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--glass-border);
    padding: 2rem 1.5rem;
    text-align: center;
    margin-top: 3rem;
}

footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

nav[aria-label="底部导航"] ul {
    list-style: none;
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

nav[aria-label="底部导航"] a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

nav[aria-label="底部导航"] a:hover {
    color: var(--accent-light);
}

/* 法律信息链接 */
#legal a {
    color: var(--accent-light);
    text-decoration: none;
    transition: var(--transition);
}

#legal a:hover {
    text-decoration: underline;
    color: var(--accent);
}

/* 知识中心链接 */
#knowledge-center a {
    color: var(--accent-light);
    text-decoration: none;
    transition: var(--transition);
}

#knowledge-center a:hover {
    text-decoration: underline;
    color: var(--accent);
}

/* 响应式布局 */
@media (max-width: 768px) {
    html {
        font-size: 14px;
    }

    header {
        padding: 0.5rem 1rem;
    }

    nav[aria-label="主导航"] ul {
        gap: 0.5rem;
    }

    nav[aria-label="主导航"] a {
        font-size: 0.85rem;
        padding: 0.4rem 0.8rem;
    }

    main {
        padding-left: 1rem;
        padding-right: 1rem;
        padding-top: 60px;
    }

    section {
        padding: 1.5rem 1rem;
        margin: 1.5rem 0;
    }

    h1 {
        font-size: 2rem;
    }

    #hero h1 {
        font-size: 2.2rem;
    }

    h2 {
        font-size: 1.6rem;
    }

    h3 {
        font-size: 1.2rem;
    }

    #hero {
        padding: 3rem 1rem;
    }

    #hero a[role="button"] {
        padding: 0.8rem 2rem;
        font-size: 1rem;
    }

    article, blockquote, details {
        padding: 1rem;
    }

    footer {
        padding: 1.5rem 1rem;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 13px;
    }

    nav[aria-label="主导航"] ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.3rem;
    }

    nav[aria-label="主导航"] a {
        font-size: 0.8rem;
        padding: 0.3rem 0.6rem;
    }

    h1 {
        font-size: 1.8rem;
    }

    #hero h1 {
        font-size: 1.9rem;
    }

    h2 {
        font-size: 1.4rem;
    }
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 8px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--accent);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-light);
}

/* 选中文本样式 */
::selection {
    background: var(--accent);
    color: #fff;
}

/* 链接通用 */
a {
    color: var(--accent-light);
    transition: var(--transition);
}

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

/* 图片适配 */
img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

/* 辅助功能 */
.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;
}