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

        :root {
            --bg: #0a0d14;
            --bg-soft: #0f131c;
            --ink: #f1f5f9;
            --ink-soft: #cbd5e6;
            --muted: #7e8aa8;
            --accent: #06b6d4;
            --accent-light: rgba(6, 182, 212, 0.12);
            --coral: #ff7b5c;
            --coral-light: rgba(255, 123, 92, 0.1);
            --mint: #2dd4bf;
            --mint-light: rgba(45, 212, 191, 0.1);
            --amber: #fbbf24;
            --amber-light: rgba(251, 191, 36, 0.1);
            --violet: #a78bfa;
            --violet-light: rgba(167, 139, 250, 0.1);
            --line: rgba(203, 213, 230, 0.08);
            --line-dark: rgba(203, 213, 230, 0.14);
            --card: #11161f;
            --card-hover: #18202c;
            --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.35);
            --shadow: 0 10px 28px rgba(0, 0, 0, 0.45);
            --shadow-lg: 0 24px 56px rgba(0, 0, 0, 0.55);
            --radius-sm: 12px;
            --radius: 18px;
            --radius-lg: 26px;
            --radius-xl: 34px;
            --ease: cubic-bezier(0.2, 0.9, 0.4, 1.1);
        }

        body {
            font-family: 'DM Sans', sans-serif;
            background: var(--bg);
            color: var(--ink);
            overflow-x: hidden;
            line-height: 1.55;
            -webkit-font-smoothing: antialiased;
        }

        ::selection {
            background: var(--accent);
            color: #0a0d14;
        }

        a {
            text-decoration: none;
            color: inherit;
            transition: all 0.25s var(--ease);
        }

        ul {
            list-style: none;
        }

        .container {
            width: 100%;
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 clamp(20px, 3vw, 48px);
        }

        h1, h2, h3, h4 {
            font-family: 'Instrument Serif', serif;
            font-weight: 400;
            letter-spacing: -0.02em;
        }

        /* 导航 (与首页完全一致) */
        nav {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 999;
            backdrop-filter: blur(20px) saturate(1.6);
            background: rgba(10, 13, 20, 0.78);
            border-bottom: 1px solid var(--line);
            transition: all 0.3s ease;
        }
        nav.scrolled {
            background: rgba(10, 13, 20, 0.92);
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
        }
        .nav-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 66px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 8px;
            font-family: 'Instrument Serif', serif;
            font-size: 1.45rem;
            font-weight: 500;
            letter-spacing: -0.01em;
        }
        .logo-icon {
            background: linear-gradient(135deg, var(--accent), #0891b2);
            width: 34px;
            height: 34px;
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            box-shadow: 0 4px 12px rgba(6, 182, 212, 0.3);
        }
        .logo-icon svg {
            width: 18px;
            height: 18px;
        }
        .nav-right {
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .nav-right a {
            padding: 8px 16px;
            border-radius: 40px;
            font-size: 0.85rem;
            font-weight: 500;
            color: var(--ink-soft);
        }
        .nav-right a:hover, .nav-right a.active {
            background: var(--accent-light);
            color: var(--accent);
        }
        .mobile-btn {
            display: none;
            background: none;
            border: none;
            color: var(--ink);
            font-size: 1.7rem;
            cursor: pointer;
        }
        .mobile-menu {
            position: fixed;
            top: 66px;
            left: 0;
            right: 0;
            background: rgba(10, 13, 20, 0.96);
            backdrop-filter: blur(28px);
            border-bottom: 1px solid var(--line);
            padding: 20px;
            display: none;
            flex-direction: column;
            gap: 14px;
            z-index: 998;
            transform: translateY(-100%);
            transition: transform 0.3s var(--ease);
        }
        .mobile-menu.show {
            transform: translateY(0);
            display: flex;
        }
        .mobile-menu a {
            font-size: 1rem;
            padding: 10px 0;
            border-bottom: 1px solid var(--line);
            color: var(--ink-soft);
        }
        .mobile-menu a.active {
            color: var(--accent);
        }

        /* 面包屑 */
        .breadcrumb {
            padding: 20px 0 6px;
            font-size: 0.75rem;
            color: var(--muted);
        }
        .breadcrumb a:hover { color: var(--accent); }

        /* Hero */
        .help-hero {
            padding-top: 110px;
            padding-bottom: 40px;
            text-align: center;
        }
        .badge {
            background: var(--card);
            border: 1px solid var(--line);
            border-radius: 100px;
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 4px 12px 4px 6px;
            font-size: 0.8rem;
            margin-bottom: 22px;
        }
        .badge-dot {
            width: 8px;
            height: 8px;
            background: var(--accent);
            border-radius: 50%;
            box-shadow: 0 0 8px var(--accent);
            animation: dotPulse 1.8s infinite;
        }
        @keyframes dotPulse {
            0%, 100% { opacity: 1; transform: scale(1);}
            50% { opacity: 0.5; transform: scale(1.3);}
        }
        .help-hero h1 {
            font-size: clamp(2.4rem, 5vw, 4rem);
            line-height: 1.15;
            margin-bottom: 16px;
        }
        .help-hero h1 em {
            background: linear-gradient(135deg, var(--accent), #2dd4bf);
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
        }
        .help-sub {
            color: var(--muted);
            max-width: 600px;
            margin: 0 auto 32px;
            font-size: 1rem;
        }

        /* 搜索框 */
        .search-box {
            max-width: 560px;
            margin: 0 auto 40px;
            position: relative;
        }
        .search-box input {
            width: 100%;
            padding: 14px 20px 14px 48px;
            background: var(--card);
            border: 1px solid var(--line);
            border-radius: 60px;
            color: var(--ink);
            font-size: 0.95rem;
            outline: none;
            transition: all 0.2s;
        }
        .search-box input:focus {
            border-color: var(--accent);
            background: var(--card-hover);
        }
        .search-box::before {
            content: "🔍";
            position: absolute;
            left: 18px;
            top: 50%;
            transform: translateY(-50%);
            font-size: 1rem;
            opacity: 0.7;
        }

        /* FAQ 分类网格 */
        .faq-categories {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 12px;
            margin: 30px 0 40px;
        }
        .cat-btn {
            background: var(--card);
            border: 1px solid var(--line);
            border-radius: 40px;
            padding: 8px 20px;
            font-size: 0.85rem;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.2s;
        }
        .cat-btn.active, .cat-btn:hover {
            background: var(--accent-light);
            border-color: var(--accent);
            color: var(--accent);
        }

        /* 问答卡片区 */
        .faq-grid {
            display: flex;
            flex-direction: column;
            gap: 24px;
            margin-bottom: 60px;
        }
        .faq-card {
            background: var(--card);
            border-radius: var(--radius-lg);
            border: 1px solid var(--line);
            overflow: hidden;
            transition: 0.2s;
        }
        .faq-question {
            padding: 20px 28px;
            font-weight: 600;
            font-size: 1.05rem;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: rgba(255,255,255,0.02);
        }
        .faq-question span:first-child {
            flex: 1;
            padding-right: 16px;
        }
        .faq-question .icon {
            font-size: 1.3rem;
            transition: transform 0.25s;
            color: var(--accent);
        }
        .faq-card.open .faq-question .icon {
            transform: rotate(45deg);
        }
        .faq-answer {
            padding: 0 28px 24px 28px;
            display: none;
            color: var(--muted);
            line-height: 1.7;
            border-top: 1px solid var(--line);
            background: rgba(0,0,0,0.1);
        }
        .faq-card.open .faq-answer {
            display: block;
        }
        .faq-answer p {
            margin: 12px 0;
        }
        .faq-answer ul, .faq-answer ol {
            margin-left: 24px;
            margin-top: 8px;
        }
        .faq-answer li {
            margin: 6px 0;
        }
        .faq-answer code {
            background: var(--bg);
            padding: 2px 6px;
            border-radius: 8px;
            font-family: 'JetBrains Mono', monospace;
            font-size: 0.8rem;
            color: var(--mint);
        }

        /* 其他帮助资源 */
        .resource-links {
            background: linear-gradient(95deg, #0f1822, #0b1018);
            border-radius: var(--radius-xl);
            padding: 44px 32px;
            margin: 30px 0 50px;
            text-align: center;
        }
        .resource-grid {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 28px;
            margin-top: 28px;
        }
        .resource-item {
            background: var(--card);
            border-radius: var(--radius);
            padding: 20px 28px;
            min-width: 160px;
            transition: 0.2s;
            border: 1px solid var(--line);
        }
        .resource-item:hover {
            transform: translateY(-4px);
            border-color: var(--accent);
        }
        .resource-item .emoji {
            font-size: 2rem;
        }

        /* 统计数据 */
        .stats-row {
            display: flex;
            justify-content: center;
            gap: 40px;
            flex-wrap: wrap;
            margin: 40px 0 20px;
        }
        .stat-circle {
            text-align: center;
        }
        .stat-circle .num {
            font-size: 2rem;
            font-weight: 700;
            color: var(--accent);
            font-family: 'Instrument Serif', serif;
        }
        .footer {
            border-top: 1px solid var(--line);
            margin-top: 30px;
            padding: 50px 0 28px;
            background: var(--bg-soft);
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
        }
        .footer-col h4 { font-family: 'JetBrains Mono', monospace; font-size: 0.75rem; letter-spacing: 0.1em; margin-bottom: 16px; }
        .footer-col li { margin-bottom: 10px; }
        .footer-col a { color: var(--muted); font-size: 0.85rem; }
        .footer-col a:hover { color: var(--accent); }
        .footer-bottom { display: flex; justify-content: space-between; align-items: center; margin-top: 32px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 0.7rem; color: var(--muted); }

        @media (max-width: 1024px) {
            .footer-grid { grid-template-columns: 1fr 1fr; }
        }
        @media (max-width: 780px) {
            .nav-right a:not(.active) { display: none; }
            .mobile-btn { display: block; }
            .footer-grid { grid-template-columns: 1fr; }
            .faq-question { padding: 16px 20px; font-size: 0.95rem; }
            .faq-answer { padding: 0 20px 20px 20px; }
            .resource-grid { flex-direction: column; align-items: center; }
            .stats-row { gap: 24px; }
        }
        .reveal {
            opacity: 0;
            transform: translateY(24px);
            transition: all 0.7s var(--ease);
        }
        .reveal.show {
            opacity: 1;
            transform: translateY(0);
        }