/* Horizon Ai · dark theme, inspired by startupweekendsf.com */

@layer reset, tokens, base, layout, components, utilities, motion, responsive;

/* ========== reset ========== */
@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  html, body { margin: 0; padding: 0; }
  html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
  body { min-height: 100svh; line-height: 1.6; -webkit-font-smoothing: antialiased; }
  img, svg, video { display: block; max-width: 100%; height: auto; }
  a { color: inherit; text-decoration: none; }
  button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
  input, textarea, select { font: inherit; color: inherit; }
  ul, ol { margin: 0; padding: 0; list-style: none; }
  h1, h2, h3, h4, h5, h6, p { margin: 0; }
  [hidden] { display: none !important; }
  :focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }
}

/* ========== tokens ========== */
@layer tokens {
  :root {
    /* color */
    --bg: #000000;
    --bg-soft: #0E0E0E;
    --bg-deep: #050505;
    --ink: #FFFFFF;
    --ink-soft: #C9C9C9;
    --muted: #8A8A8A;
    --line: rgba(255, 255, 255, 0.10);
    --line-strong: rgba(255, 255, 255, 0.20);
    --panel: #0E0E0E;
    --panel-soft: #141414;
    --accent: #54ffa8;
    --accent-ink: #000000;
    --signal: #1DC48A;

    /* type */
    --font-sans: "Inter", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-mono: "JetBrains Mono", "SF Mono", "Menlo", "Consolas", monospace;
    --font-display: var(--font-sans);

    /* scale */
    --step--1: clamp(.82rem, .8rem + .1vw, .9rem);
    --step-0:  clamp(.95rem, .9rem + .2vw, 1.05rem);
    --step-1:  clamp(1.1rem, 1rem + .4vw, 1.3rem);
    --step-2:  clamp(1.3rem, 1.1rem + .8vw, 1.75rem);
    --step-3:  clamp(1.7rem, 1.3rem + 1.6vw, 2.6rem);
    --step-4:  clamp(1.8rem, 1.4rem + 2vw, 3.8rem);
    --step-5:  clamp(3rem, 2rem + 4.6vw, 6.2rem);
    --step-6:  clamp(3.6rem, 2.2rem + 6.4vw, 8.8rem);
    --step-7:  clamp(3.2rem, 2.8rem + 9vw, 12rem);

    /* layout */
    --content-max: 1320px;
    --pad-x: clamp(20px, 4vw, 56px);
    --gutter: clamp(16px, 2vw, 28px);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --radius-pill: 999px;
    --header-h: 72px;

    /* motion */
    --ease-out: cubic-bezier(.16, 1, .3, 1);
    --ease-in-out: cubic-bezier(.65, 0, .35, 1);
    --t-fast: 220ms;
    --t-med:  520ms;
    --t-slow: 900ms;
  }
}

/* ========== base ========== */
@layer base {
  html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 20px); }
  body {
    background: var(--bg);
    color: var(--ink);
    font-family: var(--font-sans);
    font-size: var(--step-0);
    opacity: 0;
    animation: pageLoad 600ms var(--ease-out) forwards 100ms;
  }
  @keyframes pageLoad { from { opacity: 0; } to { opacity: 1; } }
  h1, h2, h3 { font-family: var(--font-display); font-weight: 800; letter-spacing: -.025em; line-height: .95; }
  h1 { font-size: var(--step-7); }
  h2 { font-size: var(--step-4); line-height: 1.15; font-weight: 800; letter-spacing: -.02em; max-width: 24ch; transition: color 400ms var(--ease-out); }
  h2:hover { color: var(--accent); }
  h3 { font-size: var(--step-2); font-weight: 700; line-height: 1.15; letter-spacing: -.015em; }
  p  { color: var(--ink-soft); max-width: 60ch; }
  small { font-size: var(--step--1); color: var(--muted); }
  ::selection { background: var(--accent); color: var(--accent-ink); }
  .mono { font-family: var(--font-mono); letter-spacing: .04em; text-transform: uppercase; font-size: var(--step--1); }
  .eyebrow { display: inline-block; color: var(--accent); font-family: var(--font-mono); font-size: 10px; letter-spacing: .14em; text-transform: uppercase; padding-bottom: 6px; border-bottom: 1px solid var(--accent); transition: padding-bottom 400ms var(--ease-out), border-color 400ms, letter-spacing 400ms var(--ease-out); }
  .eyebrow:hover { padding-bottom: 8px; letter-spacing: .18em; border-color: var(--signal); }
  .eyebrow em { font-style: normal; color: var(--ink); transition: color var(--t-fast); }
  .eyebrow:hover em { color: var(--accent); }
  .kicker-mini { display: inline-block; font-family: var(--font-mono); font-size: clamp(.95rem, .8vw + .5rem, 1.15rem); color: var(--ink-soft); letter-spacing: .02em; }
  .date-pill { display: inline-flex; align-items: center; gap: 8px; padding: 0 0 0 14px; border-left: 2px solid var(--accent); background: transparent; color: var(--ink-soft); font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .14em; text-transform: uppercase; }
  .hero-date { display: inline-block; font-family: var(--font-mono); font-size: var(--step--1); letter-spacing: .14em; color: var(--ink-soft); text-transform: uppercase; }

/* ========== layout ========== */
@layer layout {
  .container { width: 100%; max-width: var(--content-max); margin-inline: auto; padding-inline: var(--pad-x); }
  .section { padding-block: clamp(80px, 10vw, 160px); }
  .section.tight { padding-block: clamp(48px, 6vw, 96px); }
  .section.alt { background: var(--bg-soft); }
  .grid { display: grid; gap: var(--gutter); }
  .grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .split { display: grid; grid-template-columns: minmax(0, 0.35fr) minmax(0, 1fr); gap: clamp(28px, 5vw, 88px); }
  .split.right { grid-template-columns: minmax(0, 1fr) minmax(0, 0.35fr); }
  .split-2 { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: clamp(28px, 5vw, 88px); align-items: start; }
  .stack { display: flex; flex-direction: column; gap: var(--gutter); }
  .row { display: flex; gap: var(--gutter); align-items: center; flex-wrap: wrap; }
}

/* ========== components ========== */
@layer components {
  /* header */
  .site-header { position: fixed; top: 16px; left: 0; right: 0; z-index: 50; transition: top var(--t-fast) var(--ease-out); pointer-events: none; }
  .site-header .container { padding: 0; max-width: none; width: 100%; }
  .header-shell { display: flex; justify-content: center; align-items: center; padding: 0 20px; pointer-events: auto; max-width: 1280px; margin: 0 auto; }

  /* nav pill (center, contains brand + nav + actions) */
  .nav-pill { display: inline-flex; align-items: center; gap: 4px; padding: 5px 6px; background: rgba(0, 0, 0, 0.7); backdrop-filter: saturate(1.8) blur(20px); -webkit-backdrop-filter: saturate(1.8) blur(20px); border: 1px solid var(--line); border-radius: 999px; box-shadow: 0 6px 20px rgba(0,0,0,0.35); transition: all 400ms var(--ease-out); animation: pill-drop 700ms var(--ease-out) both; }
  .nav-pill:hover { background: rgba(0, 0, 0, 0.82); border-color: var(--line-strong); transform: translateY(-1px); }

  @keyframes pill-drop {
    0% { opacity: 0; transform: translateY(-12px) scale(0.96); }
    60% { opacity: 1; transform: translateY(2px) scale(1.01); }
    100% { opacity: 1; transform: translateY(0) scale(1); }
  }
  .nav-inner { display: flex; align-items: center; }
  .divider { width: 1px; height: 22px; background: var(--line); flex-shrink: 0; }

  /* brand (inside nav-pill, no own chrome) */
  .brand-pill { display: inline-flex; align-items: center; gap: 8px; padding: 6px 12px 6px 8px; border-radius: 999px; text-decoration: none; color: var(--ink); transition: background 300ms var(--ease-out), transform 300ms var(--ease-out); }
  .brand-pill:hover { background: rgba(255,255,255,0.06); }
  .brand-pill:hover img { transform: rotate(-8deg) scale(1.08); }
  .brand-pill img { width: 22px; height: 22px; filter: brightness(0) invert(1); transition: transform 500ms var(--ease-out); }
  .brand-pill strong { font-family: var(--font-display); font-size: 15px; font-weight: 700; letter-spacing: -.01em; }

  /* actions (inside nav-pill, no own chrome) */
  .actions-pill { display: inline-flex; align-items: center; gap: 6px; padding-right: 2px; }
  .actions-pill .button.primary { padding: 7px 16px; font-size: 13px; min-height: 0; }
  .actions-pill .button.primary:hover { transform: translateY(-1px) scale(1.04); box-shadow: 0 6px 18px rgba(224,242,210,0.3), 0 2px 6px rgba(0,0,0,0.2); }
  .brand { display: none; }

  .nav-wrapper { display: flex; align-items: center; gap: 6px; }

  .nav { display: flex; gap: 2px; align-items: center; }
  .nav a { padding: 6px 11px; border-radius: 999px; font-size: 13px; color: var(--ink-soft); transition: color 250ms var(--ease-out), background 250ms var(--ease-out), transform 250ms var(--ease-out); font-weight: 500; white-space: nowrap; }
  .nav a:hover { color: var(--ink); background: rgba(255,255,255,0.08); transform: translateY(-1px); }
  .nav a.is-active { background: rgba(255,255,255,0.95); color: var(--bg); font-weight: 600; }

  .header-actions { display: flex; align-items: center; gap: 6px; }
  .header-actions .button { padding: 6px 14px; font-size: 13px; min-height: auto; white-space: nowrap; font-weight: 600; border-radius: 999px; }
  .lang-switch { display: inline-flex; border: 1px solid var(--line); border-radius: 999px; padding: 2px; font-family: var(--font-mono); font-size: 10px; letter-spacing: .12em; background: rgba(255,255,255,0.04); transition: border-color 300ms var(--ease-out), background 300ms var(--ease-out); }
  .lang-switch:hover { border-color: var(--line-strong); background: rgba(255,255,255,0.06); }
  .lang-switch button { padding: 4px 8px; border-radius: 999px; color: var(--muted); transition: color 250ms var(--ease-out), background 350ms var(--ease-out), transform 250ms var(--ease-out); font-weight: 500; }
  .lang-switch button:hover { color: var(--ink); }
  .lang-switch button.is-active { background: var(--ink); color: var(--bg); transform: scale(1.04); }

  .nav-toggle { display: none; width: 34px; height: 34px; position: relative; border-radius: 999px; transition: background 300ms; }
  .nav-toggle:hover { background: rgba(255,255,255,0.08); }
  .nav-toggle span { position: absolute; left: 9px; right: 9px; height: 2px; background: var(--ink); transition: transform var(--t-fast) var(--ease-out), opacity var(--t-fast); border-radius: 2px; }
  .nav-toggle span:nth-child(1) { top: 11px; }
  .nav-toggle span:nth-child(2) { top: 16px; }
  .nav-toggle span:nth-child(3) { top: 21px; }
  .nav-open .nav-toggle span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
  .nav-open .nav-toggle span:nth-child(2) { opacity: 0; }
  .nav-open .nav-toggle span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }
  .nav-toggle { display: none; width: 36px; height: 36px; position: relative; border-radius: 50%; transition: background 300ms; }
  .nav-toggle:hover { background: rgba(255,255,255,0.1); }
  .nav-toggle span { position: absolute; left: 8px; right: 8px; height: 2px; background: var(--ink); transition: transform var(--t-fast) var(--ease-out), opacity var(--t-fast); border-radius: 2px; }
  .nav-toggle span:nth-child(1) { top: 12px; }
  .nav-toggle span:nth-child(2) { top: 17px; }
  .nav-toggle span:nth-child(3) { top: 22px; }
  .nav-open .nav-toggle span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
  .nav-open .nav-toggle span:nth-child(2) { opacity: 0; }
  .nav-open .nav-toggle span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

  /* buttons */
  .button { display: inline-flex; align-items: center; gap: 10px; padding: 14px 28px; border-radius: var(--radius-pill); font-size: var(--step-0); line-height: 1; border: 1px solid transparent; transition: background var(--t-fast) var(--ease-out), color var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-out), border-color var(--t-fast) var(--ease-out), box-shadow var(--t-fast) var(--ease-out); font-weight: 600; }
  .button.primary { background: var(--ink); color: var(--bg); box-shadow: 0 2px 8px rgba(255,255,255,0.1); }
  .button.primary:hover { background: var(--accent); color: var(--accent-ink); transform: translateY(-2px) scale(1.02); box-shadow: 0 8px 24px rgba(224,242,210,0.35), 0 4px 12px rgba(0,0,0,0.2); }
  .button.primary:active { transform: translateY(0) scale(0.98); }
  .button.ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
  .button.ghost:hover { background: var(--ink); color: var(--bg); border-color: var(--ink); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(255,255,255,0.15); }
  .button .arrow { width: 14px; height: 14px; transition: transform var(--t-fast) var(--ease-out); }
  .button:hover .arrow { transform: translateX(3px); }

  /* text link (inline green accent) */
  .text-link { display: inline-flex; align-items: center; gap: 8px; color: var(--accent); position: relative; padding-bottom: 2px; transition: color var(--t-fast) var(--ease-out), gap 400ms var(--ease-out); align-self: start; }
  .text-link::after { content: ""; position: absolute; left: 0; bottom: 0; width: 100%; height: 1px; background: var(--accent); transform-origin: left; transition: transform var(--t-med) var(--ease-out), background var(--t-fast); }
  .text-link:hover { color: var(--ink); gap: 12px; }
  .text-link:hover::after { background: var(--ink); transform: scaleX(1.05); }
  .text-link span:last-child { transition: transform 400ms var(--ease-out); }
  .text-link:hover span:last-child { transform: translateX(4px); }

  /* hero (photo) */
  .hero-photo { position: relative; min-height: min(100svh, 880px); display: flex; align-items: end; padding-block: clamp(60px, 8vw, 100px); overflow: clip; color: var(--ink); }
  .hero-photo .hero-bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center 35%; z-index: 0; }
  .hero-photo .hero-veil { position: absolute; inset: 0; background: linear-gradient(180deg, rgba(0,0,0,.5) 0%, rgba(0,0,0,.3) 40%, rgba(0,0,0,.8) 100%); z-index: 1; transition: opacity 800ms var(--ease-out); }
  .hero-photo:hover .hero-veil { opacity: 0.85; }
  .hero-photo .hero-copy { position: relative; z-index: 2; display: flex; flex-direction: column; gap: 20px; max-width: 1000px; padding-bottom: clamp(20px, 3vw, 40px); }
  .hero-photo .hero-display { display: flex; flex-direction: column; gap: 0; font-size: clamp(2.8rem, 5vw + 1.5rem, 7rem); font-weight: 900; line-height: .9; letter-spacing: -.03em; margin-top: 8px; text-shadow: 0 6px 32px rgba(0,0,0,0.75), 0 3px 12px rgba(0,0,0,0.6); }
  .hero-photo .hero-display .line { display: block; transition: transform 600ms var(--ease-out), opacity 600ms; }
  .hero-photo .hero-display .line:hover { transform: translateX(4px); }
  .hero-photo .hero-display .accent { color: var(--accent); text-shadow: 0 6px 32px rgba(0,0,0,0.75); transition: text-shadow 400ms var(--ease-out); }
  .hero-photo .hero-display .accent:hover { text-shadow: 0 6px 32px rgba(0,0,0,0.75); }
  .hero-photo .hero-display .white { color: var(--ink); }
  .hero-photo .lede { color: var(--ink); font-size: var(--step-1); max-width: 58ch; text-shadow: 0 2px 16px rgba(0,0,0,0.65); line-height: 1.65; transition: transform 500ms var(--ease-out); }
  .hero-photo .lede:hover { transform: translateY(-2px); }
  .hero-photo .actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 12px; }
  .hero-photo .kicker-mini { text-shadow: 0 2px 10px rgba(0,0,0,0.5); }
  .hero-photo .hero-date { text-shadow: 0 2px 10px rgba(0,0,0,0.5); transition: color var(--t-fast), transform var(--t-fast); }
  .hero-photo .hero-date:hover { color: var(--accent); transform: scale(1.05); }

  /* page header (interior pages) */
  .page-header { padding-top: clamp(72px, 8vw, 110px); padding-bottom: clamp(36px, 4vw, 64px); border-bottom: 1px solid var(--line); }
  .page-header .crumb { display: flex; gap: 8px; font-family: var(--font-mono); font-size: 10px; letter-spacing: .14em; text-transform: uppercase; color: var(--muted); margin-bottom: 10px; }
  .page-header h1 { font-size: clamp(1.6rem, 2.8vw + .8rem, 3.6rem); line-height: 1.15; max-width: 36ch; letter-spacing: -.015em; font-weight: 800; }
  .page-header h1 em { font-style: normal; color: var(--accent); }
  .page-header .lede { margin-top: 12px; font-size: var(--step--1); max-width: 65ch; line-height: 1.6; }

  /* partner bar (marquee) */
  .partner-bar { position: relative; display: block; padding-block: 28px; border-block: 1px solid var(--line); color: var(--ink-soft); font-family: var(--font-mono); font-size: clamp(.95rem, 1vw + .3rem, 1.15rem); letter-spacing: .04em; overflow: hidden; transition: border-color 600ms var(--ease-out); }
  .partner-bar:hover { border-color: var(--line-strong); }
  .partner-bar .marquee-track { display: flex; gap: clamp(48px, 8vw, 120px); align-items: center; width: max-content; animation: marquee 28s linear infinite; will-change: transform; }
  .partner-bar:hover .marquee-track { animation-play-state: paused; }
  .partner-bar span { display: inline-block; white-space: nowrap; transition: color 400ms var(--ease-out); }
  .partner-bar:hover span { color: var(--ink); }
  @keyframes marquee { from { transform: translateX(0); } to { transform: translateX(-50%); } }

  /* section nav (right side dots) */
  .section-nav { position: fixed; right: clamp(16px, 2vw, 28px); top: 50%; transform: translateY(-50%); z-index: 40; display: flex; flex-direction: column; gap: 12px; padding: 12px 8px; background: color-mix(in oklab, var(--bg) 70%, transparent); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border: 1px solid var(--line); border-radius: var(--radius-pill); transition: transform 400ms var(--ease-out), border-color 400ms; }
  .section-nav:hover { transform: translateY(-50%) scale(1.1); border-color: var(--line-strong); }
  .section-nav a { width: 8px; height: 8px; border-radius: 50%; background: var(--line-strong); display: block; transition: background var(--t-fast) var(--ease-out), transform var(--t-fast) var(--ease-out); }
  .section-nav a.is-active { background: var(--accent); transform: scale(1.5); animation: pulse 2s ease-in-out infinite; }
  .section-nav a:hover { background: var(--ink); transform: scale(1.3); }
  @keyframes pulse { 0%, 100% { box-shadow: 0 0 0 0 rgba(139,201,122,0.7); } 50% { box-shadow: 0 0 0 6px rgba(139,201,122,0); } }

  /* text split (per-char reveal) */
  [data-split] { display: inline-block; }
  [data-split] .char-wrap { display: inline-block; }
  [data-split] .char { display: inline-block; }
  [data-split].is-splitting .char { opacity: 0; transform: translateY(.6em); transition: opacity 600ms var(--ease-out), transform 600ms var(--ease-out); transition-delay: calc(var(--i, 0) * 30ms); }
  [data-split].is-revealed .char { opacity: 1; transform: none; }

  /* card / panel */
  .card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: clamp(20px, 2.4vw, 32px); display: flex; flex-direction: column; gap: 14px; transition: border-color 420ms var(--ease-out), transform 420ms var(--ease-out), box-shadow 420ms var(--ease-out), background 420ms var(--ease-out); position: relative; overflow: hidden; }
  .card::before { content: ""; position: absolute; inset: 0; background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(224,242,210,0.1) 0%, transparent 50%); opacity: 0; transition: opacity 400ms var(--ease-out); pointer-events: none; }
  .card:hover { transform: translateY(-6px); border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent), 0 12px 48px rgba(224,242,210,0.2), 0 6px 24px rgba(0,0,0,0.4); background: color-mix(in oklab, var(--panel) 95%, var(--accent) 5%); }
  .card:hover::before { opacity: 1; }
  .card .label { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--muted); transition: color var(--t-fast); }
  .card:hover .label { color: var(--accent); }
  .card h3 { font-family: var(--font-display); transition: transform 400ms var(--ease-out); }
  .card:hover h3 { transform: translateX(4px); }
  .card p { font-size: var(--step-0); }

  /* day-card (3-col, with kicker + bold h3 + 2 paragraphs) */
  .day-card { background: transparent; border-top: 1px solid var(--line); padding: clamp(24px, 3vw, 36px) 0 clamp(28px, 3vw, 40px); display: flex; flex-direction: column; gap: 14px; transition: transform 320ms var(--ease-out), border-color var(--t-med) var(--ease-out), padding-left 400ms var(--ease-out); }
  .day-card:hover { padding-left: 8px; }
  .day-card .kicker { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); transition: color var(--t-fast), transform 400ms var(--ease-out); }
  .day-card:hover .kicker { color: var(--signal); transform: translateX(4px); }
  .day-card h3 { font-size: var(--step-3); line-height: 1; font-weight: 800; letter-spacing: -.02em; transition: color var(--t-fast), transform 400ms var(--ease-out); }
  .day-card:hover h3 { color: var(--accent); transform: translateX(2px); }
  .day-card p { font-size: var(--step-0); margin-top: 4px; transition: opacity 400ms var(--ease-out); }
  .day-card:hover p { opacity: 0.9; }
  .day-card p + p { margin-top: 8px; }
  .day-card.tilt { transform-style: preserve-3d; transition: transform 360ms var(--ease-out), border-color var(--t-med) var(--ease-out), padding-left 400ms var(--ease-out); }
  .day-card.tilt:hover { border-top-color: var(--accent); }

  .panel { background: var(--panel-soft); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: clamp(24px, 3vw, 44px); }
  .panel.dark { background: var(--bg-soft); color: var(--ink); border-color: var(--line); }
  .panel.dark p { color: var(--ink-soft); }

  /* stats */
  .stat { display: flex; flex-direction: column; gap: 8px; padding-block: 8px; }
  .stat .num { font-family: var(--font-display); font-size: var(--step-5); line-height: 1; letter-spacing: -.02em; font-weight: 800; font-feature-settings: "tnum"; }
  .stat .num small { font-size: 0.45em; color: var(--muted); margin-left: 6px; font-family: var(--font-sans); font-weight: 500; }
  .stat .key { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--muted); }
  .stat-row { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: var(--gutter); padding-block: clamp(20px, 3vw, 36px); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

  /* pill */
  .pill { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border: 1px solid var(--line-strong); border-radius: var(--radius-pill); font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--ink); background: transparent; transition: all var(--t-fast) var(--ease-out); cursor: default; }
  .pill:hover { border-color: var(--accent); background: rgba(224,242,210,0.1); transform: translateY(-2px); }
  .pill.solid { background: var(--ink); color: var(--bg); border-color: var(--ink); }
  .pill.solid:hover { background: var(--accent); border-color: var(--accent); transform: translateY(-2px) scale(1.05); }
  .pill.accent { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
  .pill.accent:hover { background: var(--signal); border-color: var(--signal); transform: translateY(-2px) scale(1.05); }
  .pill.signal { background: var(--signal); color: var(--accent-ink); border-color: var(--signal); }

  /* process band */
  .process { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(280px, 1fr); gap: var(--gutter); overflow-x: auto; scroll-snap-type: x mandatory; padding-block: 8px; margin-inline: calc(-1 * var(--pad-x)); padding-inline: clamp(20px, 4vw, 56px); scrollbar-width: none; }
  .process::-webkit-scrollbar { display: none; }
  .process .step { scroll-snap-align: start; display: flex; flex-direction: column; gap: 12px; padding: 28px; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--panel-soft); min-height: 260px; }
  .process .step .num { font-family: var(--font-display); font-size: var(--step-3); color: var(--accent); line-height: 1; font-weight: 800; }
  .process .step h3 { font-size: var(--step-1); }
  .process .step p { font-size: var(--step-0); }

  /* timeline (vertical) */
  .timeline { display: flex; flex-direction: column; gap: 0; }
  .timeline .day { display: grid; grid-template-columns: 120px 1fr; gap: clamp(20px, 3vw, 40px); padding: clamp(24px, 3vw, 36px) 0; border-top: 1px solid var(--line); }
  .timeline .day:last-child { border-bottom: 1px solid var(--line); }
  .timeline .day .when { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); }
  .timeline .day h3 { margin-bottom: 10px; font-size: var(--step-2); }
  .timeline .day .items { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 14px; }

  /* roles grid */
  .role { padding: clamp(24px, 3vw, 36px); border-radius: var(--radius-lg); background: var(--panel); border: 1px solid var(--line); display: flex; flex-direction: column; gap: 14px; min-height: 220px; }
  .role .tag { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); }
  .role h3 { font-size: var(--step-2); }
  .role .line { height: 1px; background: var(--line); margin-block: 6px; }

  /* media */
  .media { position: relative; aspect-ratio: 16 / 10; border-radius: var(--radius-lg); overflow: hidden; background: var(--bg-soft); transition: transform 400ms var(--ease-out), box-shadow 400ms var(--ease-out); }
  .media:hover { transform: scale(1.02); box-shadow: 0 8px 32px rgba(0,0,0,0.5); }
  .media img { width: 100%; height: 100%; object-fit: cover; transition: transform 1.2s cubic-bezier(.16, 1, .3, 1), filter 600ms var(--ease-out); }
  .media:hover img { transform: scale(1.08); filter: brightness(1.1); }
  .media .caption { position: absolute; left: 16px; bottom: 16px; padding: 6px 12px; background: var(--bg); color: var(--ink); border-radius: var(--radius-pill); font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; transition: transform var(--t-fast) var(--ease-out), background 400ms; }
  .media:hover .caption { transform: translateY(-8px); background: var(--accent); color: var(--accent-ink); }

  /* photo strip (full-bleed) */
  .photo-strip { position: relative; min-height: 70vh; overflow: clip; color: var(--ink); }
  .photo-strip img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; z-index: 0; }
  .photo-strip .veil { position: absolute; inset: 0; background: linear-gradient(180deg, rgba(0,0,0,.4), rgba(0,0,0,.7)); z-index: 1; }
  .photo-strip .copy { position: relative; z-index: 2; padding-block: clamp(80px, 12vw, 180px); display: flex; flex-direction: column; gap: 18px; max-width: 720px; }
  .photo-strip .year { position: absolute; left: var(--pad-x); top: 32px; z-index: 3; font-family: var(--font-mono); font-size: var(--step-1); letter-spacing: .14em; color: var(--accent); }

  /* FAQ */
  .faq { display: flex; flex-direction: column; }
  .faq details { border-top: 1px solid var(--line); padding: 22px 0; transition: border-color 400ms var(--ease-out); }
  .faq details:hover { border-top-color: var(--line-strong); }
  .faq details:last-child { border-bottom: 1px solid var(--line); }
  .faq summary { list-style: none; cursor: pointer; display: flex; align-items: center; justify-content: space-between; gap: 24px; font-family: var(--font-display); font-size: var(--step-2); font-weight: 600; transition: color var(--t-fast) var(--ease-out), padding-left 400ms var(--ease-out); }
  .faq summary:hover { color: var(--accent); padding-left: 8px; }
  .faq summary::-webkit-details-marker { display: none; }
  .faq summary .plus { width: 18px; height: 18px; position: relative; flex: none; transition: transform var(--t-med) var(--ease-out); }
  .faq summary:hover .plus { transform: rotate(90deg); }
  .faq summary .plus::before, .faq summary .plus::after { content: ""; position: absolute; left: 50%; top: 50%; background: var(--ink); transition: background var(--t-fast); }
  .faq summary:hover .plus::before, .faq summary:hover .plus::after { background: var(--accent); }
  .faq summary .plus::before { width: 18px; height: 1.5px; transform: translate(-50%, -50%); }
  .faq summary .plus::after { width: 1.5px; height: 18px; transform: translate(-50%, -50%); transition: transform var(--t-med) var(--ease-out), background var(--t-fast); }
  .faq details[open] summary .plus { transform: rotate(180deg); }
  .faq details[open] summary .plus::after { transform: translate(-50%, -50%) scaleY(0); }
  .faq .answer { max-height: 0; overflow: hidden; transition: max-height var(--t-slow) var(--ease-out), opacity var(--t-med) var(--ease-out), margin var(--t-med) var(--ease-out); opacity: 0; }
  .faq details[open] .answer { max-height: 600px; opacity: 1; margin-top: 14px; animation: fadeSlideIn 520ms var(--ease-out) forwards; }
  .faq .answer p { color: var(--ink-soft); }
  @keyframes fadeSlideIn { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: translateY(0); } }

  /* CTA banner */
  .cta-banner { padding: clamp(40px, 5vw, 80px); border-radius: var(--radius-lg); background: var(--bg-soft); color: var(--ink); display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: 32px; border: 1px solid var(--line); transition: all 600ms var(--ease-out); position: relative; overflow: hidden; }
  .cta-banner::before { content: ""; position: absolute; inset: 0; background: radial-gradient(circle at 70% 50%, rgba(224,242,210,0.08) 0%, transparent 70%); opacity: 0; transition: opacity 800ms var(--ease-out); pointer-events: none; }
  .cta-banner:hover { border-color: var(--accent); transform: translateY(-4px); box-shadow: 0 12px 48px rgba(0,0,0,0.3); }
  .cta-banner:hover::before { opacity: 1; }
  .cta-banner h2 { color: var(--ink); }
  .cta-banner p { color: var(--ink-soft); }

  /* footer (slim) */
  .footer { margin-top: clamp(80px, 10vw, 140px); padding: clamp(28px, 3vw, 40px) 0; border-top: 1px solid var(--line); background: var(--bg); }
  .footer-shell { display: grid; grid-template-columns: 1fr auto; gap: clamp(24px, 4vw, 56px); align-items: center; }
  .footer ul { display: flex; gap: 20px; align-items: center; }
  .footer a { color: var(--ink); transition: color var(--t-fast) var(--ease-out); font-size: var(--step-0); }
  .footer a:hover { color: var(--accent); }
  .footer h4 { font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--muted); margin-bottom: 18px; }
  .footer .colophon { margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--line); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 16px; color: var(--muted); font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; }

  /* contact email */
  .mail { display: block; font-family: var(--font-mono); font-size: var(--step-0); color: var(--ink); line-height: 1.3; margin-top: -4px; overflow-wrap: anywhere; }
  .mail:hover { color: var(--accent); }

  /* form */
  .form { display: grid; gap: 16px; }
  .form .row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
  .form .submit-row { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; align-items: center; margin-top: 8px; }
  .form label { display: flex; flex-direction: column; gap: 8px; font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-soft); font-weight: 500; transition: color 400ms var(--ease-out); }
  .form label:focus-within { color: var(--accent); }
  .form input, .form textarea, .form select { background: var(--bg-soft); border: 1px solid var(--line-strong); border-radius: var(--radius-md); padding: 14px 16px; font-size: var(--step-0); color: var(--ink); transition: border-color var(--t-fast) var(--ease-out), background var(--t-fast), box-shadow var(--t-fast) var(--ease-out), transform 400ms var(--ease-out); font-family: var(--font-sans); }
  .form input:hover, .form textarea:hover, .form select:hover { border-color: var(--line-strong); transform: translateY(-2px); }
  .form input::placeholder, .form textarea::placeholder { color: var(--muted); opacity: 1; transition: opacity 400ms; }
  .form input:focus::placeholder, .form textarea:focus::placeholder { opacity: 0.5; }
  .form input:focus, .form textarea:focus, .form select:focus { border-color: var(--accent); outline: none; box-shadow: 0 0 0 3px rgba(224,242,210,0.15), 0 0 20px rgba(224,242,210,0.1); background: var(--bg); transform: translateY(-2px); }
  .form textarea { min-height: 140px; resize: vertical; line-height: 1.6; }
  .form select { cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23C9C9C9' d='M6 9L1 4h10z'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 16px center; padding-right: 40px; }
  .form select option { background: var(--bg); color: var(--ink); padding: 8px; }

  /* progress bar */
  .progress { position: fixed; top: 0; left: 0; right: 0; height: 2px; background: var(--accent); transform-origin: 0 50%; transform: scaleX(0); z-index: 60; pointer-events: none; transition: transform 60ms linear; }

  /* media strip */
  .strip { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--gutter); }
  .strip .media { aspect-ratio: 4 / 5; }
}

/* ========== utilities ========== */
@layer utilities {
  .text-mute { color: var(--muted); }
  .text-ink  { color: var(--ink); }
  .text-accent { color: var(--accent); }
  .h2-sm h2 { font-size: clamp(0.95rem, 0.8rem + 0.6vw, 1.5rem); }
  .mt-0 { margin-top: 0 !important; }
  .mt-sm { margin-top: 16px; }
  .mt-md { margin-top: 32px; }
  .mt-lg { margin-top: 56px; }
  .center { text-align: center; }
  .sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
}

/* ========== motion ========== */
@layer motion {
  .reveal { opacity: 0; transform: translateY(32px); transition: opacity var(--t-slow) var(--ease-out), transform var(--t-slow) var(--ease-out), filter var(--t-slow) var(--ease-out); }
  .reveal[data-effect="blur"] { filter: blur(12px); }
  .reveal[data-effect="rise"]  { transform: translateY(56px); }
  .reveal[data-effect="scale"] { transform: scale(.94); }
  .reveal.is-visible { opacity: 1; transform: none; filter: none; }
  .reveal-stagger > * { transition-delay: calc(var(--i, 0) * 120ms); }

  .stagger-1 { --i: 0; }
  .stagger-2 { --i: 1; }
  .stagger-3 { --i: 2; }
  .stagger-4 { --i: 3; }
  .stagger-5 { --i: 4; }
  .stagger-6 { --i: 5; }
  .stagger-7 { --i: 6; }
  .stagger-8 { --i: 7; }

  @keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: .25; } }
  .blink { animation: blink 1.6s ease-in-out infinite; }

  ::view-transition-old(root) { animation: vt-out 380ms var(--ease-out) forwards; }
  ::view-transition-new(root) { animation: vt-in 380ms var(--ease-out) forwards; }
  @keyframes vt-out { to { opacity: 0; transform: scale(0.98); filter: blur(4px); } }
  @keyframes vt-in { from { opacity: 0; transform: scale(1.02); filter: blur(4px); } }

  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; scroll-behavior: auto !important; }
  }
}

/* ========== responsive ========== */
@layer responsive {
  @media (max-width: 1100px) {
    .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .footer-shell { grid-template-columns: 1fr 1fr; }
    .stat-row { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .strip { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .split, .split.right, .split-2 { grid-template-columns: 1fr; }
  }

  @media (max-width: 900px) {
    :root {
      --step-7: clamp(2.8rem, 6vw + 1rem, 10rem);
      --pad-x: clamp(20px, 4vw, 40px);
    }
    .site-header { top: 16px; max-width: calc(100% - 32px); }
    .header-shell { padding: 10px 20px; gap: 16px; }
    .nav a { padding: 7px 12px; font-size: 13px; }
    .brand strong { font-size: 15px; }
    .header-actions .button { font-size: 13px; padding: 7px 14px; }
    .hero-photo { min-height: min(90svh, 720px); padding-block: clamp(50px, 7vw, 80px); padding-top: 100px; }
    .hero-photo .hero-copy { max-width: 100%; }
    .hero-photo .lede { font-size: var(--step-0); max-width: 100%; }
    .section-nav { opacity: 0.8; transform: translateY(-50%) scale(0.85); }
    .split-2, .split { gap: clamp(24px, 4vw, 48px); }
  }

  @media (max-width: 760px) {
    :root {
      --header-h: 60px;
      --step-7: clamp(2.4rem, 8vw + .5rem, 9rem);
    }
    .site-header { top: 12px; left: 12px; right: 12px; }
    .brand-pill { padding: 8px 14px 8px 10px; }
    .brand strong { font-size: 14px; }
    .brand img { width: 22px; height: 22px; }
    .nav-pill { padding: 4px; gap: 2px; }
    .nav-pill .nav-inner { display: none; }
    .nav-pill .divider { display: none; }
    .nav-pill .actions-pill .lang-switch { display: none; }
    .nav-toggle { display: block; }

    /* mobile menu: when opened, show full menu as overlay */
    .nav-open .nav-pill { position: fixed; top: 64px; left: 12px; right: 12px; flex-direction: column; align-items: stretch; padding: 16px; border-radius: var(--radius-lg); gap: 8px; }
    .nav-open .nav-pill .nav-inner { display: flex; flex-direction: column; gap: 2px; width: 100%; }
    .nav-open .nav-pill .nav a { width: 100%; padding: 12px 16px; text-align: left; }
    .nav-open .nav-pill .actions-pill .lang-switch { display: inline-flex; }

    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .stat-row { grid-template-columns: 1fr 1fr; }
    .footer-shell { grid-template-columns: 1fr; }
    .strip { grid-template-columns: 1fr; }
    .timeline .day { grid-template-columns: 1fr; gap: 10px; }
    .form .row { grid-template-columns: 1fr; }
    .partner-bar { gap: 16px; }

    /* 移动端 Hero 优化 */
    .hero-photo { align-items: center; padding-block: clamp(40px, 6vw, 60px); padding-top: 100px; }
    .hero-photo .hero-bg { object-position: center 25%; }
    .hero-photo .hero-copy { gap: 16px; text-align: center; align-items: center; }
    .hero-photo .hero-display { font-size: clamp(2.4rem, 10vw, 4.5rem); gap: 4px; }
    .hero-photo .lede { font-size: clamp(.9rem, 3.5vw, 1.1rem); line-height: 1.6; }
    .hero-photo .actions { width: 100%; justify-content: center; }
    .hero-photo .actions .button { width: 100%; max-width: 100%; justify-content: center; min-height: 44px; padding: 14px 24px; font-size: var(--step-1); }
    .hero-photo .row { justify-content: center; text-align: center; }
    .hero-photo .hero-date { font-size: clamp(.75rem, 2.5vw, .85rem); }

    /* 移动端 Page Header 优化 */
    .page-header { padding-top: clamp(100px, 12vw, 140px); padding-bottom: clamp(40px, 5vw, 80px); }
    .page-header h1 { font-size: clamp(1.4rem, 4.5vw + .4rem, 2.2rem); line-height: 1.2; max-width: 100%; }

    /* 移动端 Section Nav 缩小 */
    .section-nav { right: 12px; padding: 8px 6px; gap: 8px; transform: translateY(-50%) scale(0.8); }
    .section-nav a { width: 6px; height: 6px; }

    /* 移动端按钮触摸优化 */
    .button { min-height: 44px; padding: 14px 24px; }

    /* 移动端卡片间距 */
    .card, .day-card, .role { padding: clamp(18px, 4vw, 28px); }

    /* 移动端间距调整 */
    .section { padding-block: clamp(60px, 10vw, 120px); }
  }

  @media (max-width: 480px) {
    :root {
      --step-7: clamp(2rem, 12vw, 3.5rem);
    }
    .hero-photo .hero-display { font-size: clamp(2rem, 12vw, 3.5rem); }
    .hero-photo .lede { font-size: .9rem; }
    .page-header h1 { font-size: clamp(1.2rem, 5.5vw, 1.9rem); }
    .section-nav { display: none; }
    .section { padding-block: clamp(50px, 12vw, 100px); }
  }
}