:root {
        --brand: #1953f2;
        --brand-light: #6f8dff;
        --cyan: #2fa3bf;
        --ink: #0f172a;
        --bg: #f6f8fd;
        --nav-h: 80px;
    }
    html { scroll-behavior: smooth; }
    body {
        background-color: var(--bg);
        color: var(--ink);
        -webkit-font-smoothing: antialiased;
    }
    section[id] { scroll-margin-top: 92px; }

    /* 背景光晕与网格（浅色） */
    .bg-aurora {
        background-image:
            radial-gradient(900px 520px at 12% -8%, rgba(25, 83, 242, .10), transparent 62%),
            radial-gradient(760px 460px at 88% 4%, rgba(47, 163, 191, .10), transparent 60%),
            radial-gradient(680px 520px at 50% 108%, rgba(79, 70, 229, .07), transparent 62%);
    }
    .bg-grid {
        background-image:
            linear-gradient(rgba(15, 23, 42, .04) 1px, transparent 1px),
            linear-gradient(90deg, rgba(15, 23, 42, .04) 1px, transparent 1px);
        background-size: 64px 64px;
        -webkit-mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 35%, transparent 100%);
        mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 35%, transparent 100%);
    }

    /* 玻璃拟态（浅色） */
    .glass {
        background: linear-gradient(150deg, rgba(255, 255, 255, .92) 0%, rgba(255, 255, 255, .64) 100%);
        border: 1px solid rgba(15, 23, 42, .08);
        backdrop-filter: blur(16px) saturate(140%);
        -webkit-backdrop-filter: blur(16px) saturate(140%);
        box-shadow: 0 12px 30px -20px rgba(15, 23, 42, .28);
    }
    .glass-strong {
        background: rgba(255, 255, 255, .92);
        border: 1px solid rgba(15, 23, 42, .08);
        backdrop-filter: blur(20px) saturate(150%);
        -webkit-backdrop-filter: blur(20px) saturate(150%);
        box-shadow: 0 16px 40px -24px rgba(15, 23, 42, .32);
    }

    .text-gradient {
        background: linear-gradient(100deg, #1443c9 0%, #1953f2 46%, #2fa3bf 100%);
        -webkit-background-clip: text;
        background-clip: text;
        -webkit-text-fill-color: transparent;
    }
    .text-gradient-brand {
        background: linear-gradient(100deg, #1953f2 0%, #2fa3bf 100%);
        -webkit-background-clip: text;
        background-clip: text;
        -webkit-text-fill-color: transparent;
    }

    /* 卡片 */
    .card-lift {
        position: relative;
        transition: transform .38s cubic-bezier(.2, .7, .3, 1), border-color .38s, box-shadow .38s, background .38s;
    }
    .card-lift:hover {
        transform: translateY(-6px);
        border-color: rgba(25, 83, 242, .35);
        box-shadow: 0 26px 54px -24px rgba(25, 83, 242, .35);
    }
    .card-active {
        border-color: rgba(25, 83, 242, .5) !important;
        box-shadow: 0 18px 44px -22px rgba(25, 83, 242, .4);
        background: linear-gradient(150deg, rgba(25, 83, 242, .1) 0%, rgba(47, 163, 191, .04) 100%);
    }

    /* 发光按钮（保持品牌蓝 + 白字） */
    .btn-glow {
        position: relative;
        overflow: hidden;
        color: #fff;
        background: linear-gradient(100deg, #1a45c4 0%, #2050d8 58%, #1c7a94 130%);
        box-shadow: 0 12px 26px -12px rgba(25, 83, 242, .55);
        transition: transform .25s, box-shadow .25s, filter .25s;
    }
    .btn-glow:hover { transform: translateY(-2px); box-shadow: 0 16px 36px -12px rgba(25, 83, 242, .7); filter: brightness(1.05); }
    .btn-glow:active { transform: translateY(0) scale(.99); }
    .btn-glow, .btn-glow * { color: #fff !important; }

    /* 导航 */
    .nav-link {
        position: relative;
        transition: color .25s;
    }
    .nav-link::after {
        content: '';
        position: absolute;
        left: 0; bottom: -7px;
        height: 2px; width: 0;
        border-radius: 2px;
        background: linear-gradient(90deg, var(--brand), var(--cyan));
        transition: width .3s cubic-bezier(.2, .7, .3, 1);
    }
    .nav-link:hover::after, .nav-link.active::after { width: 100%; }
    .nav-link.active { color: #1443c9; }

    /* 进场动画 */
    .reveal {
        opacity: 0;
        transform: translateY(26px);
        transition: opacity .7s cubic-bezier(.2, .7, .3, 1), transform .7s cubic-bezier(.2, .7, .3, 1);
    }
    .reveal.is-visible { opacity: 1; transform: none; }

    @media (prefers-reduced-motion: reduce) {
        html { scroll-behavior: auto; }
        .reveal { opacity: 1; transform: none; transition: none; }
        .card-lift { transition: none; }
        .cursor-glow { display: none; }
    }

    /* 滚动条（浅色） */
    ::-webkit-scrollbar { width: 10px; height: 10px; }
    ::-webkit-scrollbar-track { background: #eef1f7; }
    ::-webkit-scrollbar-thumb { background: #c6cfdf; border-radius: 8px; }
    ::-webkit-scrollbar-thumb:hover { background: #aab6cc; }

    /* 时间轴 */
    .timeline-line {
        background: linear-gradient(180deg, rgba(25, 83, 242, .55), rgba(47, 163, 191, .35), rgba(15, 23, 42, .06));
    }

    .tag {
        display: inline-flex; align-items: center; gap: .35rem;
        padding: .25rem .6rem;
        font-size: .7rem; font-weight: 500;
        border-radius: 999px;
        background: rgba(25, 83, 242, .08);
        border: 1px solid rgba(25, 83, 242, .22);
        color: #1443c9;
        white-space: nowrap;
    }

    .divider-soft { border-top: 1px solid rgba(15, 23, 42, .1); }

    .logo-chip {
        background: #fff;
        box-shadow: 0 6px 18px -8px rgba(15, 23, 42, .35);
    }

    /* 业务详情 Tab */
    .tab-btn { color: #475569; }
    .tab-btn:hover {
        background: rgba(25, 83, 242, .06);
        color: #1443c9;
    }
    .tab-btn.tab-active {
        background: rgba(25, 83, 242, .1);
        border: 1px solid rgba(25, 83, 242, .3);
        color: #1443c9;
    }

    /* ===================== 视觉特效 ===================== */

    /* 鼠标跟随光斑 */
    .cursor-glow {
        position: fixed;
        top: 0; left: 0;
        width: 520px; height: 520px;
        margin: -260px 0 0 -260px;
        border-radius: 50%;
        pointer-events: none;
        z-index: 1;
        background: radial-gradient(circle, rgba(25, 83, 242, .10) 0%, rgba(47, 163, 191, .07) 38%, transparent 70%);
        opacity: 0;
        transition: opacity .5s ease;
        will-change: transform;
    }
    .cursor-glow.is-on { opacity: 1; }
    @media (hover: none) { .cursor-glow { display: none; } }

    /* 卡片高光（跟随鼠标） */
    .card-shine {
        position: absolute;
        inset: 0;
        border-radius: inherit;
        pointer-events: none;
        opacity: 0;
        transition: opacity .3s ease;
        background: radial-gradient(340px circle at var(--mx, 50%) var(--my, 50%), rgba(25, 83, 242, .14), transparent 60%);
    }
    .card-lift:hover .card-shine { opacity: 1; }

    /* 浮动光斑 */
    .float-orb {
        position: absolute;
        border-radius: 50%;
        filter: blur(48px);
        pointer-events: none;
        animation: orbFloat 16s ease-in-out infinite;
    }
    @keyframes orbFloat {
        0%, 100% { transform: translate(0, 0) scale(1); }
        50% { transform: translate(24px, -34px) scale(1.08); }
    }

    /* 时间轴节点点亮 */
    .timeline-dot {
        transition: box-shadow .4s, transform .4s;
    }
    .timeline-dot.is-lit {
        box-shadow: 0 0 0 5px rgba(25, 83, 242, .14);
        transform: scale(1.12);
        border-color: var(--brand);
    }