/* site.css: shared by every page of synthe.live (the 2026-10 redesign).
   - Webfonts, self-hosted (SIL Open Font License 1.1; texts in fonts/). No request leaves the site for type.
   - One palette and type for every page, the mark, buttons, the slot diagonal, the lattice, the chrome.
   Page-specific layout stays in each page's own <style>. See DESIGN_PLAYBOOK.md before changing anything here. */

/* Hanken Grotesk normal 400 700 latin-ext */
@font-face {
  font-family: 'Hanken Grotesk';
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url(/fonts/hanken-grotesk-normal-400-700-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}

/* Hanken Grotesk normal 400 700 latin */
@font-face {
  font-family: 'Hanken Grotesk';
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url(/fonts/hanken-grotesk-normal-400-700-latin.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* IBM Plex Mono normal 400 latin-ext */
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url(/fonts/ibm-plex-mono-normal-400-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}

/* IBM Plex Mono normal 400 latin */
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url(/fonts/ibm-plex-mono-normal-400-latin.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* IBM Plex Mono normal 500 latin-ext */
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(/fonts/ibm-plex-mono-normal-500-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF;
}

/* IBM Plex Mono normal 500 latin */
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url(/fonts/ibm-plex-mono-normal-500-latin.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* Pages written before the 2026-10 redesign name "Fraunces" in their own styles. The redesign drops
   the serif: that name now resolves to Hanken Grotesk, so those pages change without being rewritten. */
@font-face {
  font-family: 'Fraunces';
  font-style: normal;
  font-weight: 400 700;
  font-display: swap;
  src: url(/fonts/hanken-grotesk-normal-400-700-latin.woff2) format('woff2');
}
@font-face {
  font-family: 'Fraunces';
  font-style: italic;
  font-weight: 400 700;
  font-display: swap;
  src: url(/fonts/hanken-grotesk-normal-400-700-latin.woff2) format('woff2');
}

/* ---------- Tokens: one palette for every page ----------
   `html:root` outranks the `:root` blocks pages still carry, so this palette wins everywhere.
   Two roles carry meaning: --agent (the agent's half of the mark, ink) and --human (your half, coral).
   The page names (--cream, --ink, --rust...) map onto the same palette. See DESIGN_PLAYBOOK.md. */
html:root, html:root[data-theme="light"] {
  --mode: light;
  --bg: #f6f0e8; --bg2: #efe7dc; --card: #fbf7f1; --line: #e2d8cb; --line2: #cfc3b4;
  --ink: #1b1613; --ink-soft: #3d352e; --muted: #5d544c; --faint: #6a6056;
  --agent: #1b1613; --human: #b5402f; --human-text: #a63a2a; --human-bg: #f6dfd8; --ok: #26663b;
  --cream: var(--bg); --cream-deep: var(--bg2); --rust: var(--human-text); --rust-deep: #8a2e21;
  --green: var(--ok); --green-soft: #e2ecdf; --red: #a3213e; --red-soft: #f5dfe3;
  --slot: 53deg; --cut: 14px; --cut-y: 19px;
  --sans: 'Hanken Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --ease-spring: cubic-bezier(.2, .9, .25, 1.12); --ease-out: cubic-bezier(.2, .8, .2, 1);
  color-scheme: light;
}
html:root[data-theme="dark"] {
  --mode: dark;
  --bg: #131110; --bg2: #1a1715; --card: #1e1a17; --line: #2e2824; --line2: #3d3631;
  --ink: #f2eadf; --ink-soft: #d9cfc2; --muted: #ab9f92; --faint: #978b7f;
  --agent: #f2eadf; --human: #e06a57; --human-text: #ec7d6b; --human-bg: #3a1f1a; --ok: #8fc9a0;
  --rust-deep: #f08a78; --green-soft: #17201a; --red: #f2607e; --red-soft: #2a161b;
  color-scheme: dark;
}
@media (prefers-color-scheme: dark) {
  html:root:not([data-theme]) {
    --mode: dark;
    --bg: #131110; --bg2: #1a1715; --card: #1e1a17; --line: #2e2824; --line2: #3d3631;
    --ink: #f2eadf; --ink-soft: #d9cfc2; --muted: #ab9f92; --faint: #978b7f;
    --agent: #f2eadf; --human: #e06a57; --human-text: #ec7d6b; --human-bg: #3a1f1a; --ok: #8fc9a0;
    --rust-deep: #f08a78; --green-soft: #17201a; --red: #f2607e; --red-soft: #2a161b;
    color-scheme: dark;
  }
}

/* ---------- Type and texture shared by every page ---------- */
html body { background-color: var(--bg); background-image: none !important; color: var(--ink); font-family: var(--sans); }
h1, h2, h3, h4, .feature-title, .panel-h { text-wrap: balance; }
h1, h2 { font-weight: 650 !important; letter-spacing: -0.025em; }
h3 { font-weight: 600; }
/* The accent is used once per screen at most: headings no longer carry italic coral words. */
h1 em, h2 em, h3 em { font-style: normal !important; color: inherit !important; }
.kicker, .eyebrow { font-family: var(--mono); font-size: 13px !important; font-weight: 500; letter-spacing: 0 !important; text-transform: none !important; color: var(--human-text); }

/* ---------- The mark: two halves, the agent's (ink) and yours (coral) ----------
   Apart: waiting. Locked: committed. Refused: outlined in coral and pushed apart. Stale: dashed. */
.mark { overflow: visible; }
.mark .half { transition: transform .7s var(--ease-spring), stroke .3s, fill .3s; transform-box: view-box; }
.mark .a { fill: var(--agent); } .mark .b { fill: var(--human); }
.mark.open .a { transform: translate(-30px, -22px); } .mark.open .b { transform: translate(30px, 22px); }
.mark.refused .a { transform: translate(-34px, -26px); } .mark.refused .b { transform: translate(34px, 26px); }
.mark.refused .half { fill: none; stroke: var(--human); stroke-width: 7; }
.mark.stale .half { fill: none; stroke: var(--faint); stroke-width: 6; stroke-dasharray: 14 11; }

/* Buttons: one corner cut at the slot angle. The primary carries a small mark that locks. */
.btn2 { display: inline-flex; align-items: center; gap: 8px; font: 600 16px/1 var(--sans); padding: 12px 16px; border: 1px solid var(--line2);
  background: transparent; color: var(--ink); text-decoration: none; cursor: pointer;
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut-y), 100% 100%, 0 100%); }
.btn2:hover { border-color: var(--muted); }
.btn2.primary { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.btn2 .mark { width: 16px; height: 17px; flex: none; }
.btn2.primary .mark .a, .nav-cta .mark .a { fill: var(--bg); }
.btn2.primary:hover .mark .half, .btn2.primary:focus-visible .mark .half,
.nav-cta:hover .mark .half, .nav-cta:focus-visible .mark .half { transform: none; }

/* The one diagonal: the gap between the mark's halves, about 53 degrees. Section dividers use it. */
.slot { position: relative; height: 1px; background: var(--line); margin: 0; border: 0; }
.slot::after { content: ""; position: absolute; left: 50%; top: -9px; width: 2px; height: 19px; background: var(--human);
  transform: translateX(-50%) rotate(calc(90deg - var(--slot))); }

/* The lattice: whole brand marks in an offset grid, fading in from the right. site.js lets a soft
   glow follow the cursor over it (not on touch screens, not with reduced motion). */
.lattice, .lattice-glow { position: absolute; inset: 0; width: 100%; height: 100%; z-index: 0; pointer-events: none;
  -webkit-mask-image: linear-gradient(100deg, transparent 0 40%, #000 80%); mask-image: linear-gradient(100deg, transparent 0 40%, #000 80%); }
.lattice { opacity: .06; }
.lattice-glow { opacity: 0; transition: opacity .6s var(--ease-out);
  -webkit-mask-image: linear-gradient(100deg, transparent 0 40%, #000 80%), radial-gradient(circle 200px at var(--mx, 70%) var(--my, 40%), #000 0, rgba(0,0,0,.4) 45%, transparent 100%);
  mask-image: linear-gradient(100deg, transparent 0 40%, #000 80%), radial-gradient(circle 200px at var(--mx, 70%) var(--my, 40%), #000 0, rgba(0,0,0,.4) 45%, transparent 100%);
  -webkit-mask-composite: source-in; mask-composite: intersect; }
.lattice-glow svg { width: 100%; height: 100%; display: block; }
.lit .lattice-glow { opacity: .3; }

/* ---------- Site chrome: identical on every page ---------- */
.skip-link { position: absolute; left: 12px; top: -60px; z-index: 100; background: var(--ink); color: var(--bg);
  padding: 8px 16px; font-weight: 600; text-decoration: none; }
.skip-link:focus { top: 12px; }

.site-head {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  height: 64px; padding: 0 max(24px, calc(50vw - 548px));
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 90%, transparent); -webkit-backdrop-filter: saturate(1.2) blur(8px); backdrop-filter: saturate(1.2) blur(8px);
  margin-left: calc(50% - 50vw); margin-right: calc(50% - 50vw);
}
.wordmark { font-family: var(--sans); font-weight: 600; font-size: 20px; letter-spacing: -0.01em; color: var(--ink);
  text-decoration: none; display: inline-flex; align-items: center; gap: 8px; }
.wordmark-logo { width: 20px; height: 21px; flex: none; }
.topnav { display: flex; align-items: center; gap: 24px; }
.topnav > a:not(.nav-cta) { color: var(--muted); text-decoration: none; font-size: 16px; white-space: nowrap; }
.topnav > a:not(.nav-cta):hover, .topnav > a[aria-current="page"] { color: var(--ink); }
.topnav > a[aria-current="page"] { box-shadow: inset 0 -2px 0 var(--human); padding-bottom: 2px; }
.nav-cta { display: inline-flex; align-items: center; gap: 8px; background: var(--ink); color: var(--bg); text-decoration: none;
  font-weight: 600; font-size: 14px; padding: 8px 12px; white-space: nowrap;
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut-y), 100% 100%, 0 100%); }
.nav-cta .mark { width: 15px; height: 16px; flex: none; }

/* Theme switch: a sun and a moon, the current mode filled. It is a setting, so it does not look like the logo. */
.themeswitch { display: inline-flex; gap: 4px; background: none; border: 1px solid var(--line2); padding: 4px; cursor: pointer; flex: none;
  clip-path: polygon(0 0, calc(100% - 9px) 0, 100% 12px, 100% 100%, 0 100%); }
.themeswitch:hover { border-color: var(--muted); }
.themeswitch .opt { display: grid; place-items: center; width: 32px; height: 28px; color: var(--faint); transition: background .2s, color .2s; }
.themeswitch .opt svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
html:root[data-theme="light"] .themeswitch .sun, html:root[data-theme="dark"] .themeswitch .moon { background: var(--ink); color: var(--bg); }
@media (prefers-color-scheme: light) { html:root:not([data-theme]) .themeswitch .sun { background: var(--ink); color: var(--bg); } }
@media (prefers-color-scheme: dark) { html:root:not([data-theme]) .themeswitch .moon { background: var(--ink); color: var(--bg); } }

/* Phone menu: shown on narrow screens, and only when JavaScript runs. Without it the nav wraps. */
.nav-toggle { display: none; background: none; border: 1px solid var(--line2); padding: 8px 12px; font: inherit; font-size: 16px; font-weight: 500;
  color: var(--ink); cursor: pointer; }
.nav-toggle:hover { border-color: var(--muted); }
.themeswitch:focus-visible, .nav-toggle:focus-visible, .skip-link:focus-visible, .topnav > a:focus-visible, .nav-cta:focus-visible, .btn2:focus-visible {
  outline: 2px solid var(--human); outline-offset: 2px; }

@media (max-width: 900px) {
  .js .nav-toggle { display: inline-flex; margin-left: auto; }
  .js .topnav {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--bg); border-bottom: 1px solid var(--line);
    padding: 4px 24px 16px; max-height: calc(100vh - 64px); overflow-y: auto;
  }
  .js .site-head.nav-open .topnav { display: flex; }
  .js .topnav > a:not(.nav-cta) { padding: 12px 0; font-size: 18px; border-top: 1px solid var(--line); box-shadow: none; }
  .js .topnav > a:first-child { border-top: none; }
  .js .topnav .themeswitch { margin: 12px 0 0; align-self: flex-start; }
  .js .topnav > .nav-cta { margin-top: 12px; justify-content: center; padding: 12px; font-size: 16px; }
}

/* "On this page": a sticky in-page index for long pages, marking the section in view. */
.page-toc {
  position: sticky; top: var(--head-h, 64px); z-index: 40;
  display: flex; align-items: center; gap: 4px 20px; overflow-x: auto; scrollbar-width: none;
  margin: 24px calc(50% - 50vw) 0; padding: 8px max(24px, calc(50vw - 548px));
  background: var(--bg); border-bottom: 1px solid var(--line);
  font-size: 14px; white-space: nowrap;
}
.page-toc::-webkit-scrollbar { display: none; }
.page-toc-label { font-family: var(--mono); font-size: 12px; color: var(--muted); }
.page-toc a { color: var(--ink-soft); text-decoration: none; padding: 4px 0; border-bottom: 2px solid transparent; }
.page-toc a:hover, .page-toc a[aria-current="true"] { color: var(--ink); border-bottom-color: var(--human); }
[data-toc-target] { scroll-margin-top: calc(var(--head-h, 64px) + 64px); }

/* Back to top: one labeled, stationary button on pages longer than four screens. */
.to-top { position: fixed; right: 18px; bottom: 18px; z-index: 45; font: inherit; font-size: 14px; font-weight: 600;
  background: var(--card); color: var(--ink); border: 1px solid var(--line2); padding: 8px 16px; cursor: pointer;
  clip-path: polygon(0 0, calc(100% - 9px) 0, 100% 12px, 100% 100%, 0 100%); }
.to-top:hover { border-color: var(--muted); }
.to-top[hidden] { display: none; }

/* Decorative motion pauses on request, and stays still for anyone who prefers reduced motion. */
.motion-paused .rotator, .motion-paused .rotator-inner, .motion-paused .rotator-after,
.motion-paused .marquee-track { animation-play-state: paused !important; }

/* Footer */
.site-foot { margin-top: clamp(56px, 10vw, 92px); padding: 36px 0 8px; border-top: 1px solid var(--line);
  font-size: 14px; line-height: 1.6; color: var(--muted); }
.site-foot p { margin: 0 0 12px; }
.footer-brand { display: flex; align-items: center; gap: 8px; font-family: var(--sans); font-weight: 600; font-size: 18px; color: var(--ink); }
.footer-logo { width: 19px; height: 20px; flex: none; }
.footer-logo .a { fill: var(--agent); } .footer-logo .b { fill: var(--human); }
.footer-line { color: var(--ink-soft); max-width: 40em; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 8px 20px; margin: 16px 0 20px; }
.footer-nav a { white-space: nowrap; }
.site-foot a { color: var(--ink-soft); text-decoration: none; font-weight: 500; }
.site-foot a:hover { color: var(--ink); }
.site-foot .footer-legal { color: var(--faint); max-width: 62em; }
.site-foot .footer-legal a { text-decoration: underline; text-underline-offset: 3px; text-decoration-color: var(--line2); }
.site-foot .colophon { font-family: var(--mono); font-size: 12px; color: var(--faint); margin-bottom: 0; }
.site-foot .colophon em { font-style: normal; color: var(--muted); }

/* Numbers that come from facts.json (see tools/facts.py) */
[data-fact] { font-variant-numeric: tabular-nums; }

@media (prefers-reduced-motion: reduce) {
  .skip-link, .mark .half, .themeswitch .opt, .lattice-glow { transition: none !important; }
}

/* Visually hidden, still read by screen readers */
.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; }