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

body {
    font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, sans-serif;
    background-color: #0A0F1E;
    color: #EFF3FC;
    line-height: 1.5;
    scroll-behavior: smooth;
}

:root {
    --primary: #2A6DFF;
    --primary-dark: #1E52CC;
    --primary-glow: rgba(42, 109, 255, 0.25);
    --bg-card: #111827;
    --bg-elevated: #1E293B;
    --border-dim: #2D3A5E;
    --text-muted: #A0B3D9;
    --trust-bg: #F3F6FC;
    --trust-text: #0A1428;
}

html {
    scroll-behavior: smooth;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.2s ease;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: rgba(10, 15, 30, 0.92);
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid rgba(45, 58, 94, 0.5);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 0;
    flex-wrap: wrap;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.6rem;
    font-weight: 700;
}

.logo i {
    font-size: 2rem;
    color: var(--primary);
    transform: rotate(-20deg);
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-links a {
    font-weight: 500;
    font-size: 1rem;
}

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

.btn-outline {
    border: 1.5px solid var(--primary);
    padding: 8px 20px;
    border-radius: 40px;
    font-weight: 600;
}

.btn-primary {
    background: var(--primary);
    padding: 8px 24px;
    border-radius: 40px;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(42, 109, 255, 0.3);
}

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

.btn-outline:hover {
    background: rgba(42, 109, 255, 0.1);
}

#menu-toggle {
    display: none;
}

.menu-icon {
    display: none;
    font-size: 1.8rem;
    cursor: pointer;
}

/* 页面 Hero */
.page-hero {
    padding: 80px 0 60px;
    position: relative;
    overflow: hidden;
}

.page-hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 30% 50%, #0f172f, #030614);
    z-index: -1;
}

.page-hero-bg::before {
    content: "";
    position: absolute;
    width: 200%;
    height: 200%;
    top: -50%;
    left: -50%;
    background: radial-gradient(circle, rgba(42,109,255,0.15) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: drift 40s linear infinite;
    pointer-events: none;
}

@keyframes drift {
    0% { transform: translate(0, 0); }
    100% { transform: translate(20%, 20%); }
}

.page-hero-content {
    text-align: center;
    position: relative;
    z-index: 2;
}

.page-hero h1 {
    font-size: 3.2rem;
    font-weight: 800;
    background: linear-gradient(135deg, #FFFFFF, #7AA9FF);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 20px;
}

.page-hero .sub {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 28px;
}

/* 搜索框 */
.search-box {
    max-width: 600px;
    margin: 0 auto;
    position: relative;
    background: var(--bg-card);
    border-radius: 60px;
    border: 2px solid var(--border-dim);
    padding: 6px 6px 6px 24px;
    display: flex;
    align-items: center;
}

.search-box input {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-muted);
    font-size: 1.1rem;
    padding: 14px 10px;
    outline: none;
    font-family: inherit;
}

.search-box i {
    color: var(--text-muted);
    font-size: 1.2rem;
}

.search-box button {
    background: var(--primary);
    border: none;
    color: white;
    padding: 14px 28px;
    border-radius: 60px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
}

/* 分类导航 */
.category-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    margin: 40px 0 20px;
}

.category-chip {
    background: var(--bg-elevated);
    border: 1px solid var(--border-dim);
    color: var(--text-muted);
    padding: 10px 22px;
    border-radius: 60px;
    font-size: 0.95rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
}

.category-chip i {
    margin-right: 6px;
    font-size: 0.9rem;
}

.category-chip:hover {
    border-color: var(--primary);
    color: white;
}

/* 章节标题 */
.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 20px;
    margin-top: 40px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.1rem;
    margin-bottom: 32px;
}

.faq-section-tag {
    text-align: center;
    color: var(--primary);
    font-size: 0.9rem;
    font-weight: 600;
    letter-spacing: 2px;
    margin-bottom: 8px;
    text-transform: uppercase;
}

/* FAQ 列表 */
.faq-list {
    margin: 20px 0 64px;
    display: flex;
    flex-direction: column;
    gap: 16px;
    max-width: 860px;
    margin-left: auto;
    margin-right: auto;
}

details {
    background: var(--bg-elevated);
    border-radius: 24px;
    padding: 20px 28px;
    border: 1px solid var(--border-dim);
}

summary {
    font-weight: 700;
    font-size: 1.15rem;
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

summary::-webkit-details-marker {
    display: none;
}

summary:after {
    content: "➕";
    font-size: 1rem;
    flex-shrink: 0;
}

details[open] summary:after {
    content: "➖";
}

details p {
    margin-top: 16px;
    padding-left: 8px;
    border-left: 3px solid var(--primary);
    color: var(--text-muted);
    line-height: 1.75;
}

details ul {
    margin-top: 12px;
    padding-left: 24px;
    color: var(--text-muted);
    line-height: 1.75;
}

details ul li {
    margin: 6px 0;
}

details code {
    background: #050A15;
    padding: 2px 8px;
    border-radius: 6px;
    color: #6EE7B7;
    font-family: monospace;
    font-size: 0.9rem;
}

/* 快速入门 */
.quick-start-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    margin: 40px 0 60px;
}

.quick-card {
    background: var(--bg-card);
    border-radius: 28px;
    padding: 32px 28px;
    border: 1px solid var(--border-dim);
    transition: all 0.3s;
}

.quick-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
}

.quick-card i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 16px;
    display: block;
}

.quick-card h3 {
    font-size: 1.3rem;
    margin-bottom: 10px;
}

.quick-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* 联系支持 */
.support-section {
    background: linear-gradient(135deg, rgba(42,109,255,0.08), rgba(42,109,255,0.02));
    border-radius: 48px;
    padding: 56px 48px;
    margin: 40px 0 60px;
    text-align: center;
    border: 1px solid rgba(42,109,255,0.2);
}

.support-section h2 {
    font-size: 2.2rem;
    margin-bottom: 16px;
}

.support-section p {
    color: var(--text-muted);
    font-size: 1.1rem;
    margin-bottom: 32px;
}

.support-methods {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}

.support-method {
    background: var(--bg-card);
    border-radius: 24px;
    padding: 28px 24px;
    border: 1px solid var(--border-dim);
    min-width: 220px;
    text-align: center;
}

.support-method i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 12px;
    display: block;
}

.support-method h4 {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.support-method .detail {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* Footer */
footer {
    background: #050A15;
    padding: 48px 0 24px;
    margin-top: 80px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 32px;
}

.footer-col h4 {
    font-size: 1.1rem;
    margin-bottom: 16px;
    color: #fff;
}

.footer-col a {
    display: block;
    color: var(--text-muted);
    font-size: 0.92rem;
    margin: 8px 0;
}

.footer-col a:hover {
    color: var(--primary);
}

.footer-col .logo {
    font-size: 1.4rem;
    margin-bottom: 12px;
}

.footer-col p {
    color: var(--text-muted);
    font-size: 0.92rem;
    line-height: 1.6;
}

.social-icons {
    display: flex;
    gap: 16px;
    margin-top: 16px;
}

.social-icons a {
    font-size: 1.4rem;
    margin: 0;
    display: inline-block;
}

.copyright {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    border-top: 1px solid var(--border-dim);
    padding-top: 24px;
}

/* 移动端 */
@media (max-width: 768px) {
    .navbar {
        flex-wrap: wrap;
    }
    .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        padding: 24px 0;
        gap: 20px;
    }
    .menu-icon {
        display: block;
    }
    #menu-toggle:checked ~ .nav-links {
        display: flex;
    }
    .page-hero h1 {
        font-size: 2.2rem;
    }
    .section-title {
        font-size: 1.8rem;
    }
    .search-box {
        padding: 4px;
    }
    .search-box input {
        font-size: 1rem;
        padding: 12px 8px;
    }
    .search-box button {
        padding: 12px 20px;
        font-size: 0.9rem;
    }
    .support-section {
        padding: 32px 20px;
    }
}

@media (min-width: 769px) {
    .nav-links {
        display: flex !important;
    }
}

a, .btn-primary, .btn-outline, .category-chip, summary {
    cursor: pointer;
}