/* SpinCube 官网样式。
   自包含、零依赖——CDN 版 Tailwind 在国内会卡首屏，而这个站一共三页，
   不值得为它上一条构建流水线。颜色取自 App 的设计 token（DesignSystem.swift）。 */

:root {
    --background: #0a0d12;
    --surface: #171a21;
    --surface-elevated: #212630;
    --stroke: rgba(255, 255, 255, 0.1);
    --text-primary: #f5f5f5;
    --text-secondary: #b8b8b8;
    --text-muted: #737373;
    --accent: #47d1e5;
    --accent-soft: #142c34;
    --on-accent: #05141a;
    --radius-card: 16px;
    --radius-pill: 999px;
    --measure: 1080px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    margin: 0;
    background: var(--background);
    color: var(--text-primary);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
    font-size: 17px;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.wrap {
    max-width: var(--measure);
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------- 顶栏 ---------- */

.nav {
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(10, 13, 18, 0.82);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--stroke);
}

.nav .wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
    gap: 16px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-primary);
    font-weight: 650;
    letter-spacing: -0.01em;
}

.brand:hover {
    text-decoration: none;
}

.brand svg {
    width: 26px;
    height: 26px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
    font-size: 15px;
}

.nav-links a {
    color: var(--text-secondary);
}

.nav-links a:hover {
    color: var(--text-primary);
    text-decoration: none;
}

/* ---------- Hero ---------- */

.hero {
    padding: 84px 0 56px;
    text-align: center;
}

.hero h1 {
    margin: 0 0 16px;
    font-size: clamp(38px, 6.4vw, 62px);
    line-height: 1.08;
    letter-spacing: -0.03em;
    font-weight: 700;
}

.hero p {
    max-width: 620px;
    margin: 0 auto 32px;
    color: var(--text-secondary);
    font-size: clamp(17px, 2.2vw, 20px);
}

.accent {
    color: var(--accent);
}

.cta-row {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    align-items: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 26px;
    border-radius: var(--radius-pill);
    background: var(--accent);
    color: var(--on-accent);
    font-weight: 620;
    font-size: 16px;
}

.btn:hover {
    text-decoration: none;
    filter: brightness(1.08);
}

.btn.ghost {
    background: var(--surface-elevated);
    color: var(--text-primary);
    border: 1px solid var(--stroke);
}

.note {
    margin-top: 18px;
    color: var(--text-muted);
    font-size: 14px;
}

/* ---------- 截图 ---------- */

.shots {
    display: flex;
    gap: 18px;
    justify-content: center;
    flex-wrap: wrap;
    padding: 8px 0 72px;
}

.shots img {
    width: min(238px, 62vw);
    border-radius: 26px;
    border: 1px solid var(--stroke);
    background: var(--surface);
    display: block;
}

/* ---------- 功能块 ---------- */

.section {
    padding: 64px 0;
    border-top: 1px solid var(--stroke);
}

.section h2 {
    margin: 0 0 8px;
    font-size: clamp(26px, 3.6vw, 34px);
    letter-spacing: -0.02em;
}

.section .lede {
    margin: 0 0 40px;
    color: var(--text-secondary);
    max-width: 640px;
}

.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 16px;
}

.card {
    background: var(--surface);
    border: 1px solid var(--stroke);
    border-radius: var(--radius-card);
    padding: 24px;
}

.card h3 {
    margin: 0 0 8px;
    font-size: 18px;
}

.card p {
    margin: 0;
    color: var(--text-secondary);
    font-size: 15px;
}

.card .icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    margin-bottom: 14px;
    border-radius: 12px;
    background: var(--accent-soft);
    color: var(--accent);
    font-size: 20px;
}

/* ---------- 法务页 ---------- */

.legal {
    padding: 56px 0 88px;
    max-width: 760px;
}

.legal h1 {
    font-size: clamp(30px, 4.6vw, 40px);
    letter-spacing: -0.02em;
    margin: 0 0 6px;
}

.legal .updated {
    color: var(--text-muted);
    font-size: 14px;
    margin: 0 0 40px;
}

.legal h2 {
    font-size: 20px;
    margin: 40px 0 10px;
    letter-spacing: -0.01em;
}

.legal p,
.legal li {
    color: var(--text-secondary);
}

.legal ul {
    padding-left: 22px;
}

.legal li {
    margin-bottom: 8px;
}

.legal strong {
    color: var(--text-primary);
    font-weight: 620;
}

.callout {
    background: var(--accent-soft);
    border: 1px solid var(--accent);
    border-radius: var(--radius-card);
    padding: 20px 22px;
    margin: 28px 0;
}

.callout p {
    margin: 0;
    color: var(--text-primary);
}

/* ---------- 页脚 ---------- */

.footer {
    border-top: 1px solid var(--stroke);
    padding: 36px 0 56px;
    color: var(--text-muted);
    font-size: 14px;
}

.footer .wrap {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 22px;
    align-items: center;
    justify-content: space-between;
}

.footer a {
    color: var(--text-secondary);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 18px;
}

@media (max-width: 640px) {
    .nav-links {
        gap: 14px;
        font-size: 14px;
    }

    .hero {
        padding: 56px 0 40px;
    }

    .section {
        padding: 48px 0;
    }
}