:root {
    /* Brand colors */
    --bh-ink: #171b20;
    --bh-paper: #f7f7f5;
    --bh-paper-soft: #efeee9;
    --bh-muted: #666b70;
    --bh-copy: #4f555a;
    --bh-line: rgba(23, 27, 32, 0.22);
    --bh-accent: #c9795b;
    --bh-accent-ink: #a8583d;
    --bh-accent-soft: rgba(201, 121, 91, 0.1);
    --bh-surface-paper: #fff;
    --bh-surface-soft: #efefed;
    --bh-surface-ink: var(--bh-ink);
    --bh-surface-featured: #f2e8e1;
    --bh-surface-line: rgba(23, 27, 32, 0.18);
    --bh-surface-hover: rgba(201, 121, 91, 0.07);
    --bh-media-paper: var(--bh-surface-paper);
    --bh-media-frame: rgba(23, 27, 32, 0.72);
    --bh-media-caption: var(--bh-muted);
    --bh-media-caption-gap: 10px;
    --bh-media-shadow: 0 1rem 2.5rem rgba(23, 27, 32, 0.09);
    --bh-media-hover-scale: 1.015;

    /* Typography */
    --bh-serif: "BH Serif TC", "Noto Serif TC", Georgia, serif;
    --bh-sans: "BH Sans TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif;
    --bh-type-hero: clamp(68px, 5.8vw, 84px);
    --bh-type-hero-mobile: clamp(34px, 9vw, 40px);
    --bh-type-home-hero-mobile: clamp(46px, 12vw, 54px);
    --bh-type-section-xl: clamp(52px, 4.8vw, 72px);
    --bh-type-section: clamp(46px, 4.2vw, 64px);
    --bh-type-section-mobile: clamp(32px, 8.4vw, 40px);
    --bh-type-subsection: clamp(26px, 2.8vw, 40px);
    --bh-type-subsection-mobile: clamp(22px, 6vw, 28px);
    --bh-type-card-title: clamp(20px, 2vw, 28px);
    --bh-type-body: 17px;
    --bh-type-body-mobile: 16px;
    --bh-type-meta: 11px;
    --bh-type-meta-mobile: 10px;
    --bh-type-mark: clamp(64px, 8vw, 120px);
    --bh-type-mark-mobile: clamp(58px, 18vw, 84px);

    /* Layout rhythm */
    --bh-rhythm-roomy: clamp(84px, 7vw, 112px);
    --bh-rhythm-standard: clamp(64px, 5.5vw, 88px);
    --bh-rhythm-compact: clamp(44px, 4vw, 64px);
    --bh-rhythm-row: clamp(28px, 3vw, 48px);
    --bh-rhythm-card: clamp(24px, 2.8vw, 40px);
    --bh-rhythm-roomy-mobile: 60px;
    --bh-rhythm-standard-mobile: 52px;
    --bh-rhythm-compact-mobile: 40px;
    --bh-rhythm-row-mobile: 24px;
    --bh-rhythm-card-mobile: 20px;
    --bh-content-gap: clamp(28px, 4.5vw, 72px);
    --bh-content-gap-mobile: 24px;
    --bh-section-space: var(--bh-rhythm-roomy);
    --bh-section-space-mobile: var(--bh-rhythm-roomy-mobile);
    --bh-hero-block: clamp(520px, 70svh, 680px);
    --bh-hero-block-mobile: clamp(540px, 68svh, 620px);

    /* Controls and motion */
    --bh-control-min: 44px;
    --bh-cta-height: 48px;
    --bh-cta-height-compact: 44px;
    --bh-cta-padding-inline: 20px;
    --bh-cta-padding-inline-compact: 16px;
    --bh-cta-font-size: 12px;
    --bh-cta-font-size-compact: 11px;
    --bh-cta-letter-spacing: 0.08em;
    --bh-cta-radius: 0;
    --bh-cta-radius-pill: 999px;
    --bh-motion-fast: 180ms;
    --bh-motion-standard: 240ms;

    /* Navigation compatibility aliases; canonical values remain above. */
    --bh-menu-ink: var(--bh-ink);
    --bh-menu-paper: var(--bh-paper);
    --bh-menu-muted: var(--bh-muted);
    --bh-menu-line: var(--bh-line);
    --bh-menu-accent: var(--bh-accent);
    --bh-menu-serif: var(--bh-serif);
    --bh-menu-sans: var(--bh-sans);
}