:root{
/* V4 palette — no paper beige */
--bg:#F7F9FC;
--bg-soft:#FFFFFF;
--bg-deep:#08111F;
--bg-deep-2:#0B1F3A;
--surface:#FFFFFF;
--surface-2:#F7F9FC;
--ink:#08111F;
--ink-2:#1A2B45;
--ink-muted:#4A5B73;
--ink-faint:#7A8BA3;
--ink-on-dark:#F7F9FC;
--ink-on-dark-muted:rgba(247,249,252,.72);
--brand:#2F6BFF;
--brand-hover:#1E56E0;
--brand-soft:rgba(47,107,255,.12);
--brand-glow:rgba(105,210,255,.35);
--cyan:#69D2FF;
--accent:#FFB15A;
--accent-soft:rgba(255,177,90,.14);
--line:rgba(8,17,31,.08);
--line-strong:rgba(8,17,31,.14);
--line-on-dark:rgba(247,249,252,.12);
--focus:#2F6BFF;
--ok:#1F8A5B;
--danger:#C23B2E;
--wrap:1200px;
--gutter:24px;
--radius:14px;
--radius-sm:8px;
--font:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,sans-serif;
--fs-body:16px;--fs-sm:14px;--fs-lg:18px;
--fs-h1:clamp(2.35rem,5.2vw,4.25rem);
--fs-h2:clamp(1.65rem,3vw,2.35rem);
--fs-h3:1.15rem;
--shadow-soft:0 8px 32px rgba(8,17,31,.08);
--shadow-lift:0 16px 48px rgba(8,17,31,.14);
--header-h:72px;
--ease:cubic-bezier(.22,1,.36,1);
--dur-fast:160ms;
--dur-ui:220ms;
--dur-enter:560ms;
--dur-reveal:600ms;
--stagger:40ms;
--parallax:8%;
}