/* ============================================================
   Design System — Documentation site
   Shell, page structure and the specimens that explain the system.
   ============================================================ */

body{background:var(--bg);}

/* ================= SHELL ================= */
.shell{
  display:grid;grid-template-columns:max-content minmax(0,1fr);
  min-height:100vh;
}

/* ---------- sidebar ---------- */
.sidebar{
  position:sticky;top:0;align-self:start;z-index:40;
  display:flex;flex-direction:column;gap:28px;
  height:100vh;height:100dvh;padding:24px 20px;overflow-y:auto;overscroll-behavior:contain;
  border-right:var(--border-width) solid var(--border);background:var(--nav-bg);
}
.sidebar-head{display:flex;align-items:center;gap:10px;}
.brand{display:flex;align-items:center;gap:10px;min-width:0;padding:0 4px;color:var(--text);text-decoration:none;}
.back-trigger,.menu-trigger,.sidebar-close{
  display:grid;place-items:center;width:36px;height:36px;padding:0;flex:none;
  border:var(--border-width) solid var(--border-strong);border-radius:var(--radius-md);background:var(--surface);color:var(--accent-text);cursor:pointer;
  transition:background-color var(--duration-instant) var(--ease-standard),color var(--duration-instant) var(--ease-standard);
}
.back-trigger svg,.menu-trigger svg,.sidebar-close svg{width:var(--icon-sm);height:var(--icon-sm);}
.back-trigger:hover,.back-trigger:focus-visible,.menu-trigger:hover,.menu-trigger:focus-visible,.sidebar-close:hover,.sidebar-close:focus-visible{
  background:var(--accent-tint);border-color:var(--accent);color:var(--accent-text);outline:none;
}
.menu-trigger,.sidebar-close{color:var(--text-secondary);}
.sidebar-close{display:none;margin-left:auto;}
.brand-text{display:flex;flex-direction:column;line-height:1.2;}
.brand-name{font-size:16px;font-weight:var(--weight-bold);letter-spacing:-.01em;}
.brand-sub{font-size:var(--label-size);font-weight:var(--weight-semibold);color:var(--text);white-space:nowrap;}

/* ---------- nav ---------- */
.nav{display:flex;flex-direction:column;gap:20px;min-width:0;}
.nav-group{display:flex;flex-direction:column;gap:4px;}
.nav-label{display:none;}
.nav-link{
  display:flex;align-items:center;justify-content:space-between;gap:8px;
  width:100%;height:36px;padding:0 12px;border:0;border-radius:var(--radius-md);
  background:transparent;color:var(--text-secondary);
  font-size:var(--label-size);font-weight:var(--weight-medium);text-align:left;cursor:pointer;
  transition:background-color var(--duration-instant) var(--ease-standard),color var(--duration-instant) var(--ease-standard);
}
.nav-link:hover{background:var(--surface-hover);color:var(--text);}
.nav-link[aria-current="page"]{background:var(--accent);color:var(--on-accent);font-weight:var(--weight-semibold);}
.nav-link[aria-current="page"]:hover{background:var(--accent-hover);color:var(--on-accent);}
.nav-link:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:-2px;}

.nav-link-count{
  min-width:20px;padding:1px 6px;border-radius:var(--radius-full);background:var(--surface-sunken);
  font-size:var(--overline-size);line-height:16px;font-weight:var(--weight-semibold);text-align:center;color:var(--text-secondary);font-variant-numeric:tabular-nums;
}
.nav-link-count:empty{display:none;}
.nav-link[aria-current="page"] .nav-link-count{background:color-mix(in srgb,var(--on-accent) 24%,transparent);color:var(--on-accent);}

/* ---------- save popup ---------- */
.save-dialog{
  width:min(420px,calc(100vw - 32px));max-height:calc(100dvh - 32px);margin:auto;padding:24px;overflow-y:auto;
  border:var(--border-width) solid var(--border);border-radius:var(--radius-xl);
  background:var(--surface);color:var(--text);box-shadow:none;
}
.save-dialog::backdrop{background:var(--scrim);}
.save-dialog[open]{animation:save-dialog-in var(--duration-fast) var(--ease-standard);}
@keyframes save-dialog-in{from{opacity:0;transform:translateY(8px) scale(.98);}to{opacity:1;transform:none;}}
.save-form{display:flex;flex-direction:column;gap:16px;}
.save-form .field{max-width:none;}
.save-dialog-head{display:flex;align-items:center;justify-content:space-between;gap:12px;}
.save-dialog-head .dialog-title{margin:0;}
.save-dialog-close{
  display:grid;place-items:center;width:32px;height:32px;margin:-4px -6px -4px 0;padding:0;border:0;border-radius:var(--radius-md);
  background:transparent;color:var(--text-secondary);cursor:pointer;
}
.save-dialog-close svg{width:var(--icon-sm);height:var(--icon-sm);}
.save-dialog-close:hover{background:var(--surface-hover);color:var(--text);}
.save-dialog-close:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:2px;}
.save-form .dialog-actions{margin-top:4px;}
.save-privacy{margin:0;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.input--textarea{height:auto;min-height:88px;padding:10px 12px;resize:vertical;line-height:var(--body-line);}
.select-native{position:relative;}
.select-native select{appearance:none;-webkit-appearance:none;padding-right:36px;cursor:pointer;}
.select-native svg{position:absolute;top:50%;right:12px;width:var(--icon-sm);height:var(--icon-sm);margin-top:calc(var(--icon-sm) / -2);color:var(--text-tertiary);pointer-events:none;}

/* ---------- toast ---------- */
.save-toast{
  position:fixed;left:50%;bottom:24px;z-index:60;transform:translateX(-50%);
  display:flex;align-items:center;gap:10px;max-width:calc(100vw - 32px);padding:10px 14px;
  border:var(--border-width) solid var(--border-strong);border-radius:var(--radius-lg);
  background:var(--surface);color:var(--text);box-shadow:none;
  font-size:var(--label-size);line-height:var(--label-line);
  animation:save-dialog-in var(--duration-fast) var(--ease-standard);
}
.save-toast[hidden]{display:none;}
.save-toast > svg{width:var(--icon-sm);height:var(--icon-sm);flex:none;color:var(--success);}
.save-toast button{padding:0;border:0;background:none;color:var(--accent-text);font-weight:var(--weight-semibold);text-decoration:underline;text-underline-offset:3px;cursor:pointer;white-space:nowrap;}
@media (prefers-reduced-motion:reduce){.save-dialog[open],.save-toast{animation:none;}}

/* ---------- saved page ---------- */
.saved-bar{display:flex;flex-wrap:wrap;align-items:flex-start;justify-content:space-between;gap:16px;margin-bottom:44px;}
.saved-bar .btn{flex:none;}
.saved-bar .saved-filters{flex:0 1 auto;min-width:0;margin-bottom:0;}
.saved-empty .btn{margin-top:6px;}
.save-form .field[hidden]{display:none;}
.saved-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:30px;}
.saved-card{padding:24px;gap:14px;}
.saved-card-head{display:flex;align-items:center;justify-content:space-between;gap:8px;}
.saved-card-title{margin:0;font-size:var(--title-size);line-height:var(--title-line);font-weight:var(--weight-semibold);overflow-wrap:anywhere;}
.saved-card-actions{display:flex;align-items:center;gap:2px;margin:-6px -8px -6px 0;}
.saved-links{margin:0;padding:0;list-style:none;display:flex;flex-direction:column;gap:6px;}
.saved-links li{display:flex;align-items:center;gap:6px;min-width:0;}
.saved-links .saved-card-link{min-width:0;}
.saved-link-remove{
  display:grid;place-items:center;flex:none;width:24px;height:24px;padding:0;border:0;border-radius:var(--radius-sm);
  background:transparent;color:var(--text-tertiary);cursor:pointer;
}
.saved-link-remove svg{width:var(--icon-xs);height:var(--icon-xs);}
.saved-link-remove:hover{background:var(--surface-hover);color:var(--text);}
.saved-link-remove:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:1px;}
.saved-link-form{display:flex;flex-direction:column;gap:6px;}
.saved-link-row{display:flex;gap:6px;}
.saved-link-input{flex:1;min-width:0;height:var(--control-sm,32px);font-size:var(--body-size);}
.saved-link-input[aria-invalid="true"]{border-color:var(--danger);}
.saved-link-help{color:var(--danger);}
.saved-link-help[hidden]{display:none;}
.saved-card-link{
  display:inline-flex;align-items:center;gap:6px;align-self:flex-start;max-width:100%;
  color:var(--accent-text);font-size:var(--body-size);line-height:var(--body-line);font-weight:var(--weight-medium);
  text-decoration:underline;text-underline-offset:3px;
}
.saved-card-link span{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}
.saved-card-link svg{width:var(--icon-xs);height:var(--icon-xs);flex:none;}
.saved-card-link:hover{text-decoration-thickness:2px;}
.saved-card-link:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:3px;border-radius:var(--radius-xs);}
.saved-card-note{margin:0;font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);white-space:pre-wrap;overflow-wrap:anywhere;}
.saved-card-foot{margin-top:auto;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.saved-empty{display:flex;flex-direction:column;align-items:center;gap:10px;padding:56px 16px;border:1px dashed var(--border-strong);border-radius:var(--radius-lg);text-align:center;color:var(--text-secondary);}
.saved-empty svg{width:28px;height:28px;color:var(--text-tertiary);}
.saved-empty strong{color:var(--text);font-weight:var(--weight-semibold);}

/* ---------- mobile bar + drawer scrim (hidden on desktop) ---------- */
.scrim{display:none;}

.main{min-width:0;padding:64px 56px;}

@media (max-width:960px){
  .shell{display:block;}
  .sidebar{
    position:fixed;top:0;left:0;width:max-content;min-width:min(240px,86vw);max-width:86vw;height:100vh;height:100dvh;gap:20px;
    padding-top:calc(24px + env(safe-area-inset-top,0px));
    box-shadow:none;
    transform:translateX(-100%);visibility:hidden;
    transition:transform var(--duration-fast) var(--ease-standard),visibility 0s linear var(--duration-fast);
  }
  .sidebar-close{display:grid;}
  .scrim{
    display:block;position:fixed;inset:0;z-index:35;background:rgba(0,0,0,.4);
    opacity:0;visibility:hidden;
    transition:opacity var(--duration-fast) var(--ease-standard),visibility 0s linear var(--duration-fast);
  }
  .is-nav-open .sidebar{transform:none;visibility:visible;transition-delay:0s;}
  .is-nav-open .scrim{opacity:1;visibility:visible;transition-delay:0s;}
  .is-nav-open{overflow:hidden;}
  .main{padding:48px 32px;}
}

@media (prefers-reduced-motion:reduce){
  .sidebar,.scrim{transition:none;}
}

@media (max-width:600px){
  .main{padding:40px 20px;}
}

/* ---------- touch: 44px targets wherever the drawer layout is used ---------- */
@media (max-width:960px){
  .menu-trigger,.back-trigger,.sidebar-close{width:var(--touch-min);height:var(--touch-min);}
  .nav-link{height:var(--touch-min);}
  .filter-bar button{height:var(--touch-min);}
  .saved-bar .btn{height:var(--touch-min);}
  .saved-card .saved-card-actions{margin:-8px -10px -8px 0;}
  .saved-card .saved-card-actions .btn{width:var(--touch-min);height:var(--touch-min);}
  .saved-links li{min-height:var(--touch-min);}
  .saved-link-remove{width:var(--touch-min);height:var(--touch-min);margin-right:-10px;}
  .saved-link-input{height:var(--touch-min);}
  .save-dialog-close{width:var(--touch-min);height:var(--touch-min);margin:-10px -12px -10px 0;}
  .save-dialog .btn,.save-dialog .input:not(textarea){height:var(--touch-min);}
}

/* ================= PAGE ================= */
.page{max-width:1120px;margin:0 auto;}
.page-head{display:flex;flex-direction:column;gap:6px;margin-bottom:48px;}
.eyebrow{
  font-size:var(--overline-size);line-height:var(--overline-line);font-weight:var(--weight-semibold);
  letter-spacing:.08em;text-transform:uppercase;color:var(--accent-text);
}
.page-title{font-size:var(--h1-size);line-height:var(--h1-line);font-weight:var(--weight-bold);letter-spacing:-.005em;}
.page-intro{font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);max-width:68ch;text-wrap:pretty;}
.page-count{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);font-variant-numeric:tabular-nums;}
.empty{padding:32px 0;color:var(--text-tertiary);}

.group{display:flex;flex-direction:column;gap:32px;margin-bottom:72px;}
.group-header{display:flex;flex-direction:column;gap:4px;}
.section-label{font-size:var(--overline-size);line-height:16px;font-weight:var(--weight-semibold);letter-spacing:.08em;text-transform:uppercase;color:var(--text-tertiary);}
.group-head{display:flex;flex-wrap:wrap;align-items:baseline;gap:2px 12px;}
.group-title{font-size:var(--h3-size);line-height:var(--h3-line);font-weight:var(--weight-semibold);}
.group-meta{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);font-variant-numeric:tabular-nums;}
.group-desc,.doc-text{display:none;}

.grid{display:grid;gap:30px;grid-template-columns:repeat(auto-fill,minmax(min(var(--min,200px),100%),1fr));}
.grid--2{--min:340px;}
.grid--3{--min:260px;}

.card{
  display:flex;flex-direction:column;gap:12px;min-width:0;padding:12px;
  border:var(--border-width) solid var(--border);border-radius:var(--radius-lg);background:var(--surface);
}
.card--wide{grid-column:1 / -1;}
.card--pad{padding:20px;}

.stage{
  position:relative;height:104px;border-radius:var(--radius-md);background:var(--surface-sunken);
  display:flex;align-items:center;justify-content:center;overflow:hidden;perspective:600px;
}
.card-foot{display:flex;align-items:center;justify-content:space-between;gap:8px;min-width:0;}
.card-text{display:flex;flex-direction:column;gap:1px;min-width:0;}
.card-name{font-size:var(--label-size);line-height:var(--label-line);font-weight:var(--weight-semibold);overflow-wrap:anywhere;}
.card-spec{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);font-variant-numeric:tabular-nums;}

/* ---------- documentation cards ---------- */
.doc-demo{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:12px;
  min-height:128px;padding:24px 16px;border-radius:var(--radius-md);background:var(--surface-sunken);
}
.doc-demo--column{flex-direction:column;}
.doc-demo--start{align-items:flex-start;justify-content:flex-start;}
.doc-body{display:flex;flex-direction:column;gap:6px;padding:2px 4px 4px;}
.doc-title{font-size:var(--title-size);line-height:var(--title-line);font-weight:var(--weight-semibold);}
.doc-text{font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);}

.spec-chips{list-style:none;margin:4px 0 0;padding:0;display:flex;flex-wrap:wrap;gap:6px;}
.spec-chips li{
  display:inline-flex;align-items:baseline;gap:6px;padding:3px 16px;border-radius:var(--radius-full);
  background:var(--surface-sunken);font-size:var(--caption-size);line-height:var(--caption-line);
  color:var(--text);font-variant-numeric:tabular-nums;
}
.spec-chips li span{color:var(--text-tertiary);}

.state-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(190px,1fr));gap:22px 18px;width:100%;}
.state-cell{display:flex;flex-direction:column;align-items:flex-start;gap:10px;min-width:0;}
.state-name{
  font-size:var(--overline-size);line-height:var(--overline-line);font-weight:var(--weight-semibold);
  letter-spacing:.08em;text-transform:uppercase;color:var(--text-tertiary);
}
.stack{display:flex;flex-direction:column;gap:10px;width:100%;}
.row{display:flex;flex-wrap:wrap;align-items:center;gap:12px;}

/* ---------- tables ---------- */
.table-scroll{overflow-x:auto;}
.table{width:100%;border-collapse:collapse;font-size:var(--body-size);line-height:var(--body-line);font-variant-numeric:tabular-nums;}
.table th{
  padding:10px 12px;text-align:left;white-space:nowrap;border-bottom:var(--border-width) solid var(--border-strong);
  font-size:var(--overline-size);line-height:var(--overline-line);font-weight:var(--weight-semibold);
  letter-spacing:.08em;text-transform:uppercase;color:var(--text-tertiary);
}
.table td{padding:12px;border-bottom:var(--border-width) solid var(--border);color:var(--text-secondary);vertical-align:middle;}
.table tbody tr:last-child td,.table tbody tr:last-child th{border-bottom:0;}
.table td.strong,.table tbody th{color:var(--text);font-weight:var(--weight-semibold);white-space:nowrap;text-align:left;}
.table tbody th{
  padding:12px;border-bottom:var(--border-width) solid var(--border);
  font-size:var(--label-size);line-height:var(--label-line);text-transform:none;letter-spacing:0;
}

.matrix th,.matrix td{text-align:center;}
.matrix thead th:first-child,.matrix tbody th{text-align:left;}
.matrix td{padding:16px 12px;}

.grade{display:inline-flex;align-items:center;gap:8px;white-space:nowrap;}
.grade-badge{
  padding:2px 7px;border-radius:var(--radius-full);font-size:var(--overline-size);font-weight:var(--weight-semibold);letter-spacing:.04em;
}
.grade-badge--pass{background:var(--success-tint);color:var(--success);}
.grade-badge--large{background:var(--warning-tint);color:var(--warning);}
.grade-badge--fail{background:var(--danger-tint);color:var(--danger);}

/* ================= TYPOGRAPHY ================= */
.typeface{display:grid;grid-template-columns:minmax(200px,340px) 1fr;gap:28px;padding:20px;}
@media (max-width:760px){.typeface{grid-template-columns:1fr;}}
.typeface-specimen{
  display:flex;align-items:flex-end;min-height:220px;padding:18px 22px;border-radius:var(--radius-md);
  background:var(--accent);color:var(--on-accent);
  font-size:136px;line-height:.9;font-weight:var(--weight-bold);letter-spacing:-.03em;overflow:hidden;
}
.typeface-info{display:flex;flex-direction:column;gap:12px;min-width:0;}
.typeface-name{font-size:var(--h2-size);line-height:var(--h2-line);font-weight:var(--weight-bold);}
.weights{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;}
@media (max-width:1100px) and (min-width:761px),(max-width:480px){.weights{grid-template-columns:repeat(2,minmax(0,1fr));}}
.weight{display:flex;flex-direction:column;padding:10px 12px;border-radius:var(--radius-md);background:var(--surface-sunken);}
.weight-sample{font-size:28px;line-height:36px;}
.weight-name{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.charset{font-size:var(--body-lg-size);line-height:var(--body-lg-line);color:var(--text-secondary);letter-spacing:.02em;overflow-wrap:anywhere;}

.platform-bar{display:flex;flex-wrap:wrap;align-items:flex-start;gap:12px 28px;}
.platform-notes{
  flex:1 1 320px;max-width:68ch;margin:0;padding-left:18px;
  display:flex;flex-direction:column;gap:4px;
  font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);
}

.browser{border:var(--border-width) solid var(--border-strong);border-radius:var(--radius-xl);background:var(--surface-sunken);overflow:hidden;}
.browser-bar{display:flex;align-items:center;gap:14px;padding:10px 14px;border-bottom:var(--border-width) solid var(--border);background:var(--surface);}
.browser-dots{display:flex;gap:6px;flex:none;}
.browser-dots i{width:10px;height:10px;border-radius:50%;background:var(--border-strong);}
.browser-url{flex:1;max-width:340px;padding:4px 12px;border-radius:var(--radius-full);background:var(--surface-sunken);font-size:12px;color:var(--text-tertiary);}
.browser-screen{display:flex;flex-direction:column;gap:10px;padding:14px;}

.device{width:390px;max-width:100%;margin-inline:auto;padding:10px 10px 18px;border:var(--border-width) solid var(--border-strong);border-radius:44px;background:var(--surface);}
.device-status{display:flex;align-items:center;justify-content:space-between;padding:6px 22px 10px;font-size:13px;font-weight:var(--weight-semibold);}
/* hardware, not interface — black in both modes */
.device-notch{width:96px;height:26px;border-radius:var(--radius-full);background:#050505;}
.device-screen{display:flex;flex-direction:column;gap:8px;padding:12px;border-radius:34px;background:var(--surface-sunken);}

.type-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:32px;}
.type-row{display:flex;flex-direction:column;justify-content:flex-start;align-items:flex-start;gap:8px;min-height:190px;padding:24px;background:var(--surface);border-color:var(--border);}
.type-row--mobile{gap:8px;}
@media (max-width:560px){.type-grid{grid-template-columns:1fr;}.type-row{min-height:160px;}}
.type-meta{display:flex;flex-direction:column;gap:2px;}
.type-row--mobile .type-meta{flex-direction:row;flex-wrap:wrap;align-items:baseline;gap:2px 10px;}
.type-name{font-size:var(--label-size);line-height:var(--label-line);font-weight:var(--weight-semibold);}
.type-spec{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);font-variant-numeric:tabular-nums;}
.type-sample{min-width:0;color:var(--text);overflow-wrap:anywhere;}

.in-use--mobile{max-width:360px;}

/* ================= COLOURS ================= */
.accent-hero{display:grid;grid-template-columns:minmax(220px,1fr) 1.3fr;gap:0;padding:0;overflow:hidden;}
@media (max-width:760px){.accent-hero{grid-template-columns:1fr;}}
.accent-hero-swatch{
  display:flex;flex-direction:column;justify-content:flex-end;gap:4px;min-height:240px;padding:22px;
  background:var(--accent);color:var(--on-accent);
}
.accent-hero-name{font-size:var(--h2-size);line-height:var(--h2-line);font-weight:var(--weight-bold);}
.accent-hero-values{font-size:var(--body-size);line-height:var(--body-line);opacity:.85;font-variant-numeric:tabular-nums;}
.accent-hero-text{display:flex;flex-direction:column;gap:12px;padding:24px;}
.rule-list{margin:0;padding:0;list-style:none;display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:8px;}
.rule-list li{display:grid;grid-template-columns:20px 1fr;gap:8px;font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);}
.rule-list svg{width:var(--icon-sm);height:var(--icon-sm);margin-top:3px;}
.rule-list .yes svg{color:var(--success);}
.rule-list .no svg{color:var(--danger);}

.scale{display:grid;grid-template-columns:repeat(auto-fit,minmax(88px,1fr));border-radius:var(--radius-lg);overflow:hidden;border:var(--border-width) solid var(--border);}
.scale-chip{display:flex;flex-direction:column;justify-content:space-between;gap:18px;min-height:132px;padding:12px;font-variant-numeric:tabular-nums;}
.scale-step{font-size:var(--label-size);line-height:var(--label-line);font-weight:var(--weight-bold);}
.scale-hex{font-size:var(--caption-size);line-height:var(--caption-line);}
.scale-ratio{font-size:var(--overline-size);line-height:16px;}
.scale-tag{
  align-self:flex-start;padding:2px 6px;border-radius:var(--radius-full);
  font-size:var(--overline-size);font-weight:var(--weight-bold);letter-spacing:.06em;text-transform:uppercase;
}

.status-swatches{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:8px;}
.status-swatch{display:flex;flex-direction:column;justify-content:flex-end;min-height:84px;padding:10px;border-radius:var(--radius-md);font-size:var(--caption-size);line-height:var(--caption-line);font-variant-numeric:tabular-nums;}
.status-swatch strong{font-size:var(--label-size);}

.role-list{margin:0;padding:0;list-style:none;display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:8px 12px;}
.role-list li{display:flex;align-items:center;gap:8px;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);min-width:0;}
.role-dot{flex:none;width:22px;height:22px;border-radius:var(--radius-sm);border:var(--border-width) solid var(--border);}

/* ================= VARIABLES ================= */
.variable-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:30px;}
.variable-card{min-height:172px;padding:24px;gap:14px;}
.variable-card .var-preview{min-height:48px;padding:8px;border-radius:var(--radius-md);background:var(--surface-sunken);}
.variable-card .var-use{margin-top:auto;}
.token-preview{display:flex;align-items:center;gap:12px;}
.token-preview .var-preview{flex:1;min-width:0;}
.token-preview .var-value{flex:0 1 52%;font-size:var(--label-size);font-weight:var(--weight-semibold);color:var(--text);text-align:right;overflow-wrap:anywhere;}
.variable-card--token .var-name{margin-top:2px;}
.color-mode-switch{margin-bottom:14px;}
.variable-card--color{min-height:112px;}
.var-color-line{display:flex;align-items:center;gap:12px;min-width:0;}
.var-color-line .role-dot{width:42px;height:42px;border-radius:var(--radius-md);}
.var-color-code{margin-top:2px;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);font-variant-numeric:tabular-nums;overflow-wrap:anywhere;}

.var-table{padding:0;gap:0;overflow:hidden;}
.var-row,.var-head{
  display:grid;grid-template-columns:72px minmax(150px,1fr) minmax(100px,.7fr) minmax(0,1.6fr);
  align-items:center;gap:16px;padding:12px 18px;
}
.var-table--color .var-row,.var-table--color .var-head{grid-template-columns:56px minmax(150px,1fr) minmax(140px,1fr) minmax(0,1.3fr);}
.var-head{
  padding-top:10px;padding-bottom:10px;background:var(--surface-sunken);
  font-size:var(--overline-size);line-height:var(--overline-line);font-weight:var(--weight-semibold);
  letter-spacing:.08em;text-transform:uppercase;color:var(--text-tertiary);
}
.var-row{border-top:var(--border-width) solid var(--border);}
.var-head + .var-row{border-top:0;}
.var-preview{display:flex;align-items:center;min-height:32px;}
.var-name{font-size:var(--body-size);line-height:var(--body-line);font-weight:var(--weight-semibold);color:var(--text);overflow-wrap:anywhere;}
.var-value{font-size:var(--body-size);line-height:var(--body-line);color:var(--text);font-variant-numeric:tabular-nums;}
.var-mode{display:flex;align-items:center;gap:8px;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);font-variant-numeric:tabular-nums;min-width:0;}
.var-mode .role-dot{width:18px;height:18px;border-radius:var(--radius-xs);}
.var-use{font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.var-pair{position:relative;width:44px;height:30px;}
.var-pair i{position:absolute;width:28px;height:28px;border-radius:var(--radius-sm);border:var(--border-width) solid var(--border-strong);}
.var-pair i:first-child{left:0;top:0;}
.var-pair i:last-child{right:0;bottom:0;}

.var-bar{display:block;height:12px;min-width:2px;border-radius:2px;background:var(--accent);}
.var-radius{width:40px;height:40px;border:var(--border-width-strong) solid var(--accent);background:var(--accent-tint);}
.var-box{border:var(--border-width) dashed var(--accent);background:var(--accent-tint);border-radius:var(--radius-xs);}
.var-icon{color:var(--accent);}
.var-line{width:48px;background:var(--accent);border-radius:1px;}
.var-focus{width:28px;height:20px;border-radius:var(--radius-sm);background:var(--surface-pressed);outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:var(--focus-offset);margin-left:4px;}
.var-elev{width:44px;height:30px;border-radius:var(--radius-sm);background:var(--surface);border:var(--border-width) solid var(--border);}
.var-opacity{
  position:relative;width:40px;height:40px;border-radius:var(--radius-sm);overflow:hidden;
  background:repeating-conic-gradient(var(--surface-hover) 0% 25%, var(--surface) 0% 50%) 0 0/10px 10px;
}
.var-opacity i{position:absolute;inset:0;background:var(--neutral-900);}
.var-weight{font-size:26px;line-height:1;}
.var-grid{display:flex;gap:2px;width:64px;height:30px;padding:3px;border-radius:var(--radius-xs);background:var(--surface-sunken);border:var(--border-width) solid var(--border);}
.var-grid i{flex:1;background:var(--accent-tint-strong);border-radius:1px;}
.var-track{position:relative;display:block;width:64px;height:8px;border-radius:var(--radius-full);background:var(--surface-pressed);}
.var-track i{
  position:absolute;top:50%;left:0;width:8px;height:8px;margin-top:-4px;border-radius:50%;background:var(--accent);
  animation:var-track-sweep var(--dur,250ms) ease-in-out infinite alternate;
}

.var-curve{width:40px;height:40px;}
.var-curve .curve-path{fill:none;stroke:var(--accent);stroke-width:6;stroke-linecap:round;vector-effect:non-scaling-stroke;}
.var-curve .grid-path{fill:none;stroke:var(--border);stroke-width:2;vector-effect:non-scaling-stroke;}

@media (max-width:760px){
  .var-head{display:none;}
  .var-row,.var-table--color .var-row{
    grid-template-columns:56px 1fr;grid-template-areas:"p n" "p v" "p u";gap:2px 14px;align-items:start;
  }
  .var-table--color .var-row{grid-template-areas:"p n" "p l" "p u";}
  .var-preview{grid-area:p;}
  .var-name{grid-area:n;}
  .var-value{grid-area:v;}
  .var-use{grid-area:u;}
  .var-mode--light{grid-area:l;}
  .var-mode--dark{grid-area:d;}
}

/* ================= COMPONENT QUICK REFERENCE ================= */
/* page header details that belong to the old layout stay out of sight */
.page-head > .eyebrow,.page-count,.section-label,.group-meta{display:none;}
.principles-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:30px;}
.principle-card{min-height:174px;padding:24px;gap:14px;}
.principle-visual{display:grid;place-items:center;width:36px;height:36px;border-radius:var(--radius-md);background:var(--accent-tint);color:var(--accent-text);font-size:var(--overline-size);font-weight:var(--weight-semibold);letter-spacing:.04em;}
.principle-visual svg{width:20px;height:20px;}
.principle-visual--law{position:relative;display:flex;align-items:center;width:100%;height:58px;padding:10px 42px 10px 12px;border-radius:var(--radius-md);}
.law-number{position:absolute;top:10px;right:12px;font-size:var(--overline-size);font-weight:var(--weight-semibold);letter-spacing:.06em;color:var(--text-tertiary);}
.law-diagram{display:flex;align-items:center;gap:6px;width:100%;height:100%;}
.law-diagram i{display:block;background:var(--accent);}
.law-diagram--choices i{width:12px;height:12px;border-radius:50%;}
.law-diagram--choices i:nth-child(2),.law-diagram--choices i:nth-child(4){background:var(--text-tertiary);border-radius:var(--radius-xs);}
.law-diagram--target{gap:14px;}
.law-diagram--target i:first-child{width:12px;height:12px;border:2px solid var(--text-tertiary);border-radius:50%;background:transparent;}
.law-diagram--target i:last-child{width:28px;height:28px;border-radius:50%;}
.law-diagram--patterns{gap:8px;}
.law-diagram--patterns i{width:34px;height:20px;border-radius:var(--radius-xs);}
.law-diagram--patterns i:last-child{background:var(--surface);border:2px solid var(--accent);}
.law-diagram--chunks{gap:3px;max-width:76px;flex-wrap:wrap;}
.law-diagram--chunks i{width:20px;height:11px;border-radius:2px;}
.law-diagram--chunks i:nth-child(3){margin-left:12px;}
.law-diagram--gaps{gap:4px;}
.law-diagram--gaps i{width:16px;height:16px;border-radius:var(--radius-xs);}
.law-diagram--gaps i:nth-child(3){margin-left:18px;background:var(--text-tertiary);}

.law-diagram--response{position:relative;max-width:120px;height:10px;border-radius:var(--radius-full);background:var(--surface-pressed);overflow:hidden;}
.law-diagram--response i:first-child{width:78%;height:100%;border-radius:inherit;}.law-diagram--response i:last-child{position:absolute;right:6px;width:8px;height:8px;border-radius:50%;background:var(--surface);}
.law-diagram--peak{align-items:flex-end;gap:5px;}
.law-diagram--peak i{width:13px;border-radius:2px 2px 0 0;}.law-diagram--peak i:nth-child(1){height:11px;background:var(--text-tertiary);}.law-diagram--peak i:nth-child(2){height:26px;}.law-diagram--peak i:nth-child(3){height:16px;background:var(--text-secondary);}.law-diagram--peak i:nth-child(4){height:22px;}

.law-diagram--standout{gap:6px;}
.law-diagram--standout i{width:12px;height:12px;border-radius:50%;background:var(--text-tertiary);}
.law-diagram--standout i:nth-child(3){width:20px;height:20px;background:var(--accent);}

.principle-card p{margin:0;color:var(--text-secondary);font-size:var(--body-size);line-height:var(--body-line);}
.motion-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:30px;}
.motion-card{padding:24px;gap:16px;}
.motion-stage{display:grid;place-items:center;min-height:128px;border-radius:var(--radius-md);background:var(--surface-sunken);overflow:hidden;}
.motion-object{display:block;width:38px;height:38px;border-radius:var(--radius-md);background:var(--accent);}
.motion-object--fade{animation:motion-fade 2.4s ease-in-out infinite;}
.motion-object--slide-up{animation:motion-slide-up 2.4s var(--ease-enter) infinite;}

.motion-object--scale{animation:motion-scale 2.4s var(--ease-enter) infinite;}
.motion-object--pop{animation:motion-pop 2.4s var(--ease-standard) infinite;}
.motion-object--bounce{animation:motion-bounce 1.4s ease-in-out infinite;}
.motion-object--shake{animation:motion-shake 1.2s ease-in-out infinite;}

.motion-object--pulse{animation:motion-pulse 1.8s ease-in-out infinite;}
.motion-object--ripple{border-radius:50%;animation:motion-ripple 1.8s ease-out infinite;}
.motion-object--glow{animation:motion-glow 1.8s ease-out infinite;}
.motion-object--float{animation:motion-float 2.2s ease-in-out infinite;}

.motion-object--loading{width:36px;height:36px;border:4px solid var(--border-strong);border-top-color:var(--accent);border-radius:50%;background:transparent;animation:motion-rotate 1s linear infinite;}
.motion-object--shimmer{width:70%;height:14px;background:linear-gradient(90deg,var(--surface-pressed) 0%,var(--surface) 45%,var(--surface-pressed) 100%);background-size:200% 100%;animation:motion-shimmer 1.4s linear infinite;}

@keyframes motion-fade{0%{opacity:0}30%,75%{opacity:1}100%{opacity:0}}
@keyframes motion-slide-up{0%{transform:translateY(32px);opacity:0}30%,75%{transform:none;opacity:1}100%{transform:none;opacity:0}}
@keyframes motion-scale{0%{transform:scale(.4);opacity:0}30%,75%{transform:none;opacity:1}100%{transform:none;opacity:0}}
@keyframes motion-pop{0%{transform:scale(.4);opacity:0}18%{transform:scale(1.2);opacity:1}32%,75%{transform:none;opacity:1}100%{transform:none;opacity:0}}
@keyframes motion-bounce{0%,100%{transform:translateY(0)}50%{transform:translateY(-22px)}}
@keyframes motion-shake{0%,100%{transform:translateX(0)}25%{transform:translateX(-10px)}75%{transform:translateX(10px)}}
@keyframes motion-pulse{0%,100%{transform:scale(1);opacity:.75}50%{transform:scale(1.22);opacity:1}}
@keyframes motion-ripple{0%{transform:scale(.5);opacity:1}100%{transform:scale(2.5);opacity:0}}
@keyframes motion-glow{0%{box-shadow:0 0 0 0 color-mix(in srgb,var(--accent) 60%,transparent)}100%{box-shadow:0 0 0 20px transparent}}
@keyframes motion-float{0%,100%{transform:translateY(8px)}50%{transform:translateY(-16px)}}
@keyframes motion-rotate{to{transform:rotate(360deg)}}
@keyframes motion-shimmer{from{background-position:200% 0}to{background-position:-100% 0}}
@media (prefers-reduced-motion:reduce){#page-animations:not(.motion-allowed) .motion-object{animation:none !important;}}
/* One filter control for every page: a white pill bar, scrolls sideways instead of wrapping. */
.filter-bar{display:flex;width:max-content;max-width:100%;gap:2px;padding:4px;margin-bottom:44px;border:1px solid var(--border);border-radius:var(--radius-full);background:var(--surface);overflow-x:auto;scrollbar-width:none;}
.filter-bar::-webkit-scrollbar{display:none;}
.filter-bar button{flex:none;height:32px;padding:0 16px;border:0;border-radius:var(--radius-full);background:var(--surface);color:var(--text-secondary);font:inherit;font-size:var(--caption-size);font-weight:var(--weight-semibold);white-space:nowrap;cursor:pointer;transition:background .15s ease,color .15s ease;}
.filter-bar button:hover{color:var(--text);}
.filter-bar button[aria-pressed="true"]{background:var(--accent);color:var(--on-accent);}
.filter-bar button:focus-visible{outline:2px solid var(--focus-ring);outline-offset:1px;}
@media (prefers-reduced-motion:reduce){.filter-bar button{transition:none;}}
.component-family{scroll-margin-top:24px;margin-bottom:48px;gap:28px;}
/* one card per row: the Definition / When to use / Why use it tiles need the width to sit side by side */
.component-grid{display:grid;grid-template-columns:minmax(0,1fr);gap:28px;align-items:start;}
.component-card{gap:16px;padding:24px;}
.component-card--span{grid-column:span 2;}
.component-card-head{display:flex;align-items:flex-start;justify-content:space-between;gap:10px;min-width:0;}
.component-card-head .spec-chips{justify-content:flex-end;margin:0;text-align:right;}
.component-card-head .spec-chips li{white-space:nowrap;}
.component-card > .doc-title{font-size:var(--label-size);line-height:var(--label-line);}
.component-card .doc-demo{min-height:116px;padding:20px 12px;gap:14px;}
.component-card .spec-chips{margin:0;gap:4px 12px;}
.component-card .spec-chips li{padding:0;background:none;border-radius:0;gap:4px;}
.component-card .state-grid{gap:16px;}
.component-card .state-name{font-size:var(--overline-size);letter-spacing:.04em;}
.component-card--button-variants .doc-demo{justify-content:center;}
.component-card--button-variants .state-cell{align-items:center;}
.component-card .grid--2{grid-template-columns:repeat(2,minmax(0,1fr));}
.component-card .dialog-stage{min-height:220px;padding:16px;}
.component-card .dialog{max-width:360px;}

.basic-upload > svg,.basic-empty > svg{width:24px;height:24px;color:var(--text-tertiary);}

.basic-empty{display:flex;flex-direction:column;align-items:center;gap:12px;font-size:var(--label-size);}

@media(max-width:960px){
  .component-card--span{grid-column:auto;}
  .component-family{scroll-margin-top:88px;}
}
@media(max-width:640px){
  .component-grid{grid-template-columns:minmax(0,1fr);}
  .component-card .grid--2{grid-template-columns:minmax(0,1fr);}
  .component-card .dialog{padding:16px;}
  .component-card .dialog-actions{flex-wrap:wrap;}
  .component-card .state-grid{grid-template-columns:repeat(auto-fit,minmax(min(100%,190px),1fr));}
  .component-card-head{flex-wrap:wrap;}
  .component-card-head .spec-chips{justify-content:flex-start;text-align:left;}
}

/* ================= BUTTONS ================= */

.marked{position:relative;display:inline-flex;align-items:center;}

/* ================= REFERENCE PAGES: HEURISTICS, RESEARCH, PATTERNS, PRODUCT ================= */
#page-heuristics .page-head,#page-research .page-head,#page-patterns .page-head,#page-product .page-head{margin-bottom:36px;}
#page-heuristics .page-head > .eyebrow,#page-heuristics .page-count,#page-heuristics .section-label,
#page-research .page-head > .eyebrow,#page-research .page-count,#page-research .section-label,
#page-patterns .page-head > .eyebrow,#page-patterns .page-count,#page-patterns .section-label,
#page-product .page-head > .eyebrow,#page-product .page-count,#page-product .section-label{display:none;}

.ref-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,300px),1fr));gap:30px;}
.ref-grid--wide{grid-template-columns:repeat(auto-fill,minmax(min(100%,420px),1fr));}
.ref-card{padding:24px;gap:14px;}
.is-filtered-out{display:none !important;}
.ref-head{display:flex;align-items:center;justify-content:space-between;gap:6px 10px;flex-wrap:wrap;}
.ref-text{margin:0;color:var(--text-secondary);font-size:var(--body-size);line-height:var(--body-line);}
.ref-facts{margin:0;display:flex;flex-direction:column;border-top:var(--border-width) solid var(--border);}
.ref-facts > div{display:grid;grid-template-columns:92px minmax(0,1fr);gap:12px;padding:10px 0;border-bottom:var(--border-width) solid var(--border);}
.ref-facts > div:last-child{border-bottom:0;padding-bottom:0;}
.ref-facts dt{margin:0;font-size:var(--overline-size);line-height:var(--label-line);font-weight:var(--weight-semibold);letter-spacing:.08em;text-transform:uppercase;color:var(--text-tertiary);}
.ref-facts dd{margin:0;font-size:var(--label-size);line-height:var(--label-line);color:var(--text);}
.ref-card .spec-chips{margin:0;}

/* ---------- pattern wireframes: plain greyscale blocks ---------- */
.wf{display:flex;flex-direction:column;gap:8px;height:148px;padding:14px;border-radius:var(--radius-md);background:var(--surface-sunken);overflow:hidden;}
.wf-row{display:flex;gap:8px;min-height:0;}
.wf-col{display:flex;flex-direction:column;gap:6px;min-width:0;}
.wf-fill{flex:1 1 0;min-width:0;min-height:0;}
.wf-center{align-items:center;justify-content:center;}
.wf-between{align-items:center;justify-content:space-between;}
.wf-t{flex:none;width:100%;height:6px;border-radius:3px;background:var(--border-strong);}
.wf-t.wf-s{width:72%;}
.wf-t.wf-xs{width:36%;}
.wf-t.wf-h{width:56%;height:8px;background:var(--text-tertiary);}
.wf-t.wf-xl{width:44%;height:22px;border-radius:6px;background:var(--text-tertiary);}
.wf-box{background:var(--surface);border:var(--border-width) solid var(--border);border-radius:6px;}
.wf-img{background:var(--surface-pressed);border-radius:6px;}
.wf-circle{flex:none;width:32px;height:32px;border-radius:50%;}
.wf-dashed{background:transparent;border:2px dashed var(--text-tertiary);}
.wf-field{flex:none;width:100%;height:16px;border:var(--border-width) solid var(--border-strong);border-radius:5px;background:var(--surface);}
.wf-center > .wf-field{width:70%;}
.wf-btn{flex:none;width:46%;height:16px;border-radius:8px;background:var(--accent);}
.wf-btn.wf-ghost{background:transparent;border:var(--border-width) solid var(--border-strong);}
.wf-row > .wf-btn{width:56px;}
.wf-dots{display:flex;gap:5px;}
.wf-dot{width:5px;height:5px;border-radius:50%;background:var(--border-strong);}
.wf-dot.wf-on{background:var(--accent);}
.wf-stat{flex:1;height:28px;}
.wf-bars{display:flex;align-items:flex-end;gap:8px;padding:8px 10px;}
.wf-bars i{flex:1;border-radius:3px 3px 0 0;background:var(--text-tertiary);}
.wf-bars i:nth-child(4){background:var(--accent);}
.wf-side{flex:none;width:30%;}
.wf-list{flex:none;width:38%;}
.wf-item{flex:none;height:18px;}
.wf-item.wf-on{border:2px solid var(--accent);}
.wf-pane{display:flex;flex-direction:column;gap:6px;padding:10px;}
.wf-chip{width:34px;height:12px;border-radius:6px;border:var(--border-width) solid var(--border-strong);background:var(--surface);}
.wf-rows{display:flex;flex-direction:column;justify-content:space-around;padding:6px 12px;}
.wf-rows .wf-col{width:45%;}
.wf-toggle{flex:none;width:22px;height:12px;border-radius:6px;background:var(--accent);}
.wf-swatch{width:12px;height:12px;border-radius:50%;background:var(--border-strong);}
.wf-summary{display:flex;flex-direction:column;justify-content:space-between;flex:none;width:38%;padding:10px;}
.wf-summary .wf-btn{width:100%;}

/* ---------- framework parts ---------- */
.fw-parts{display:grid;grid-template-columns:repeat(var(--n),minmax(0,1fr));gap:8px;}
.fw-parts span{display:flex;flex-direction:column;align-items:center;gap:2px;min-width:0;padding:12px 6px;border-radius:var(--radius-md);background:var(--surface-sunken);}
.fw-parts b{font-size:var(--title-size);line-height:var(--title-line);font-weight:var(--weight-bold);}
.fw-parts em{font-style:normal;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);text-align:center;}
@media (max-width:560px){
  .fw-parts--many{grid-template-columns:repeat(2,minmax(0,1fr));}
}

/* ============================================================
   Presentation layer: three ideas from Apple's design principles
   Clarity     Large type, one idea per card, plain words.
   Deference   The page recedes. Cards are flat, with no outlines.
   Depth       Layers come from tone and soft translucency.
   Everything here is presentation only: tokens and content are untouched.
   ============================================================ */
:root{
  --fill:rgba(0,0,0,.05);
  --fill-strong:rgba(0,0,0,.09);
  --hairline:rgba(0,0,0,.08);
  --segment-on:#ffffff;
  --segment-shadow:0 1px 3px rgba(0,0,0,.14),0 0 0 .5px rgba(0,0,0,.04);
  --card-radius:24px;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --fill:rgba(255,255,255,.08);--fill-strong:rgba(255,255,255,.13);--hairline:rgba(255,255,255,.12);
    --segment-on:var(--neutral-700);--segment-shadow:0 1px 3px rgba(0,0,0,.5);
  }
}
[data-theme="dark"]{
  --fill:rgba(255,255,255,.08);--fill-strong:rgba(255,255,255,.13);--hairline:rgba(255,255,255,.12);
  --segment-on:var(--neutral-700);--segment-shadow:0 1px 3px rgba(0,0,0,.5);
}

/* ---------- sidebar: the same canvas as the page, nothing boxed ---------- */
.sidebar{padding:28px 16px;gap:24px;border-right:0;background:var(--bg);}
.sidebar-head{padding:0 6px;}
.brand-sub{font-size:var(--body-lg-size);font-weight:var(--weight-bold);letter-spacing:-.01em;}
.back-trigger,.menu-trigger,.sidebar-close{border:0;background:var(--fill);color:var(--text);}
.back-trigger:hover,.back-trigger:focus-visible,.menu-trigger:hover,.menu-trigger:focus-visible,.sidebar-close:hover,.sidebar-close:focus-visible{
  background:var(--fill-strong);border-color:transparent;color:var(--text);
}
.back-trigger:focus-visible,.menu-trigger:focus-visible,.sidebar-close:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:2px;}


.nav{gap:4px;}
.nav-group{gap:2px;}
.nav-link{height:40px;padding:0 12px;border-radius:12px;font-size:var(--body-size);color:var(--text-secondary);}
.nav-link:hover{background:var(--fill);color:var(--text);}
.nav-link[aria-current="page"]{background:var(--surface);color:var(--text);font-weight:var(--weight-semibold);box-shadow:0 1px 2px rgba(0,0,0,.06),0 0 0 .5px var(--hairline);}
.nav-link[aria-current="page"]:hover{background:var(--surface);color:var(--text);}
.nav-link[aria-current="page"] .nav-link-count{background:var(--fill);color:var(--text-secondary);}

/* ---------- page header: a large title and one plain sentence ---------- */
.main{padding:40px 64px 128px;}
.page{max-width:1080px;}
.page-head{gap:12px;margin-bottom:56px;}
.page-title{font-size:48px;line-height:52px;font-weight:var(--weight-bold);letter-spacing:-.03em;}
.page-intro{max-width:30em;font-size:19px;line-height:28px;color:var(--text-secondary);}

/* ---------- sections ---------- */
.group{gap:28px;margin-bottom:88px;}
.group-title{font-size:var(--h2-size);line-height:var(--h2-line);font-weight:var(--weight-bold);letter-spacing:-.02em;}

/* ---------- filters: a segmented control ---------- */
.filter-bar{gap:2px;padding:3px;margin-bottom:56px;border:0;background:var(--fill);}
.filter-bar button{height:34px;padding:0 16px;background:transparent;color:var(--text-secondary);font-size:var(--label-size);font-weight:var(--weight-medium);
  transition:background-color var(--duration-fast) var(--ease-standard),color var(--duration-fast) var(--ease-standard),box-shadow var(--duration-fast) var(--ease-standard);}
.filter-bar button:hover{color:var(--text);}
.filter-bar button[aria-pressed="true"]{background:var(--segment-on);color:var(--text);font-weight:var(--weight-semibold);box-shadow:var(--segment-shadow);}

/* ---------- cards: flat, generous, no outline ---------- */
.card{border:0;border-radius:var(--card-radius);}
.ref-card,.principle-card,.component-card,.saved-card{padding:28px;gap:18px;}
.ref-grid,.principles-grid,.motion-grid,.saved-grid{gap:24px;}
.component-grid{gap:24px;}
.doc-demo,.stage{border-radius:var(--radius-lg);}
.card .doc-title{font-size:20px;line-height:28px;font-weight:var(--weight-semibold);letter-spacing:-.01em;}
.component-card .doc-title{font-size:var(--body-lg-size);line-height:var(--label-line);letter-spacing:0;}
.doc-text--shown{display:block;font-size:var(--body-lg-size);line-height:24px;color:var(--text-secondary);}
.ref-text,.principle-card p{font-size:var(--body-lg-size);line-height:24px;}

.ref-facts{border-top:var(--border-width) solid var(--hairline);}
.ref-facts > div{border-bottom-color:var(--hairline);}
.ref-facts dd{font-size:var(--body-size);line-height:var(--body-line);}
.table th,.table td{border-bottom-color:var(--hairline);}

/* ---------- motion: pages arrive, they don't jump ---------- */

.page:not([hidden]){animation:page-in var(--duration-slow) var(--ease-enter) both;}
@media (prefers-reduced-motion:reduce){.page:not([hidden]){animation:none;}}

/* ---------- smaller screens ---------- */
@media (max-width:960px){
  .main{padding:32px 20px 96px;}
  .page-head{margin-bottom:36px;}
  .page-title{font-size:34px;line-height:40px;}
  .page-intro{font-size:var(--body-lg-size);line-height:26px;}
  .filter-bar{margin-bottom:40px;}
  .filter-bar button{height:var(--touch-min);}
  .group{margin-bottom:64px;}
  .sidebar{background:color-mix(in srgb,var(--bg) 82%,transparent);backdrop-filter:saturate(180%) blur(24px);-webkit-backdrop-filter:saturate(180%) blur(24px);}
}
@media (max-width:600px){
  .main{padding:28px 20px 96px;}
}

/* components: as many columns as fit comfortably, never squeezed */
.component-grid{grid-template-columns:minmax(0,1fr);}
.component-card{padding:24px;}
@media (max-width:560px){
  .ref-facts > div{grid-template-columns:minmax(0,1fr);gap:2px;}
}

/* ============================================================
   Top bar: search lives here, on every screen size.
   The sidebar is only as wide as its widest label.
   ============================================================ */
.topbar{
  position:sticky;top:0;z-index:30;
  background:color-mix(in srgb,var(--bg) 82%,transparent);
  backdrop-filter:saturate(180%) blur(20px);-webkit-backdrop-filter:saturate(180%) blur(20px);
  border-bottom:var(--border-width) solid var(--hairline);
}
.topbar-inner{display:flex;align-items:center;justify-content:center;gap:12px;max-width:1208px;margin:0 auto;padding:12px 64px;}
.menu-trigger,.topbar-title{display:none;}
.topbar-title{flex-direction:column;min-width:0;line-height:1.25;}
.topbar-sub{font-size:var(--caption-size);color:var(--text-tertiary);}
.topbar-page{font-size:var(--body-lg-size);font-weight:var(--weight-semibold);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}

.search{
  position:relative;display:flex;align-items:center;gap:8px;flex:1 1 0;min-width:0;height:40px;padding:0 12px;
  border-radius:12px;background:var(--fill);color:var(--text-tertiary);cursor:text;
  transition:background-color var(--duration-fast) var(--ease-standard),box-shadow var(--duration-fast) var(--ease-standard);
}
.search:hover{background:var(--fill-strong);}
.search:focus-within{background:var(--surface);color:var(--text);box-shadow:0 0 0 var(--border-width-strong) var(--focus-ring);}
.search svg{width:var(--icon-sm);height:var(--icon-sm);flex:none;}
.search input{
  flex:1;min-width:0;height:100%;padding:0;border:0;outline:0;background:transparent;color:var(--text);
  font-size:var(--body-size);-webkit-appearance:none;appearance:none;
}
.search input::placeholder{color:var(--text-tertiary);}

@media (max-width:960px){
  /* 20px sides, the same as the page below, so the bar lines up with the content */
  .topbar-inner{justify-content:flex-start;max-width:none;padding:10px 20px;padding-top:calc(10px + env(safe-area-inset-top,0px));}
  .menu-trigger{display:grid;}
  .topbar-title{display:flex;flex:0 0 auto;max-width:38%;}
  .search{width:auto;min-width:0;height:var(--touch-min);}
  /* typing gives the field the whole bar */
  .topbar-inner:has(.search input:focus) .topbar-title{display:none;}
  .topbar-inner:has(.search input:focus) .search{flex:1;}
  .main{padding-top:28px;}
}
.sidebar{scrollbar-width:none;}
.sidebar::-webkit-scrollbar{display:none;}

/* ---------- sidebar icons ---------- */
.nav-link-main{display:flex;align-items:center;gap:12px;min-width:0;}
.nav-link-main svg{width:var(--icon-md);height:var(--icon-md);flex:none;color:var(--text-tertiary);transition:color var(--duration-fast) var(--ease-standard);}
.nav-link:hover .nav-link-main svg,.nav-link[aria-current="page"] .nav-link-main svg{color:var(--text);}

@keyframes page-in{from{opacity:0;transform:translateY(8px);}to{opacity:1;transform:none;}}
@keyframes var-track-sweep{from{left:0}to{left:calc(100% - 8px)}}

.motion-caption{margin:0;font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);}
.motion-note{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px;margin-bottom:32px;padding:16px 20px;border-radius:var(--radius-lg);background:var(--surface);font-size:var(--body-size);color:var(--text-secondary);}

/* ---------- sidebar groups: UI, UX, Product ---------- */
.nav{gap:24px;}
.nav-group{gap:2px;}
.nav-label{
  display:block;padding:0 12px 8px;
  font-size:var(--overline-size);line-height:var(--overline-line);font-weight:var(--weight-bold);
  letter-spacing:.08em;text-transform:uppercase;color:var(--text);
}
/* desktop: a little tighter so all three groups fit a laptop screen without scrolling */
@media (min-width:961px){
  .nav{gap:20px;}
  .nav-link{height:36px;}
}
@media (min-width:961px){
  .nav-link{height:34px;}
}

/* ---------- Saved: beside search, in the top bar ---------- */
.topbar-saved{
  display:inline-flex;align-items:center;gap:8px;flex:none;height:40px;padding:0 14px;
  border:0;border-radius:12px;background:var(--fill);color:var(--text);
  font-size:var(--body-size);font-weight:var(--weight-medium);cursor:pointer;
  transition:background-color var(--duration-fast) var(--ease-standard),box-shadow var(--duration-fast) var(--ease-standard);
}
.topbar-saved svg{width:var(--icon-md);height:var(--icon-md);flex:none;}
.topbar-saved:hover{background:var(--fill-strong);}
.topbar-saved:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:2px;}
.topbar-saved[aria-current="page"]{background:var(--surface);font-weight:var(--weight-semibold);box-shadow:0 1px 2px rgba(0,0,0,.06),0 0 0 .5px var(--hairline);}
.topbar-saved .nav-link-count{background:var(--surface);}
.topbar-saved[aria-current="page"] .nav-link-count{background:var(--fill);}
@media (max-width:960px){
  .topbar-saved{width:var(--touch-min);height:var(--touch-min);justify-content:center;padding:0;position:relative;}
  .topbar-saved-label{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;}
  .topbar-saved .nav-link-count{position:absolute;top:2px;right:2px;min-width:18px;padding:0 5px;font-size:var(--overline-size);line-height:18px;}
  .topbar-inner:has(.search input:focus) .topbar-saved{display:none;}
}

/* ---------- Save here: a plus beside Saved ---------- */
.topbar-add{
  display:inline-flex;align-items:center;justify-content:center;flex:none;width:40px;height:40px;padding:0;
  border:0;border-radius:12px;background:var(--accent);color:var(--on-accent);cursor:pointer;
  transition:background-color var(--duration-fast) var(--ease-standard);
}
.topbar-add svg{width:var(--icon-md);height:var(--icon-md);flex:none;}
.topbar-add:hover{background:var(--accent-hover);}
.topbar-add:focus-visible{outline:var(--border-width-strong) solid var(--focus-ring);outline-offset:2px;}
@media (max-width:960px){
  .topbar-add{width:var(--touch-min);height:var(--touch-min);}
  .topbar-inner:has(.search input:focus) .topbar-add{display:none;}
}

/* ============================================================
   Header layout: one bar across the top, the sidebar always below it.
   Logo, search and Saved sit together in the middle of the bar.
   ============================================================ */
:root{--topbar-h:65px;}
.topbar-brand{display:none;}
.topbar-inner{width:100%;}
@media (min-width:961px){
  /* The bar's content box is the page's: the sidebar, then the main padding (64px), then the 1080px page, centred. */
  :root{--sidebar-w:180px;}
  .shell{grid-template-columns:var(--sidebar-w) minmax(0,1fr);grid-template-rows:auto 1fr;}
  .topbar-inner{
    --gutter:max(0px,calc((100% - var(--sidebar-w) - 128px - 1080px) / 2));
    max-width:none;margin:0;justify-content:flex-start;
    padding-left:calc(var(--sidebar-w) + 64px + var(--gutter));padding-right:calc(64px + var(--gutter));
  }
  .topbar{grid-column:1 / -1;grid-row:1;}
  .sidebar{grid-column:1;grid-row:2;top:var(--topbar-h);height:calc(100vh - var(--topbar-h));height:calc(100dvh - var(--topbar-h));padding-top:20px;}
  .main{grid-column:2;grid-row:2;min-width:0;}
  .topbar-brand{display:flex;align-items:center;gap:10px;flex:none;}
  .sidebar-head{display:none;}
}

/* ---------- Tool guides: a Tools post written out ---------- */
.tg-stack{display:flex;flex-direction:column;gap:30px;}
.tool-guide{padding:32px;gap:24px;}
.tg-head{display:flex;flex-direction:column;align-items:flex-start;gap:8px;}
.tg-title{margin:0;font-size:var(--h2-size,28px);line-height:var(--h2-line,36px);font-weight:var(--weight-bold);letter-spacing:-.01em;overflow-wrap:anywhere;}
.tg-by{margin:0;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.tg-summary{margin:0;max-width:64ch;font-size:var(--body-size);line-height:var(--body-line);color:var(--text-secondary);}
.tg-groups{display:grid;align-items:start;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:12px;}
.tg-group{display:flex;flex-direction:column;gap:12px;padding:16px;border-radius:var(--radius-lg);background:var(--surface-sunken);min-width:0;}
.tg-group-title{margin:0;font-size:var(--body-size);line-height:var(--body-line);font-weight:var(--weight-semibold);}
.tg-group-note{margin:2px 0 0;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-tertiary);}
.tg-chips{margin:0;padding:0;list-style:none;display:flex;flex-wrap:wrap;gap:6px;}
.tg-chips li{padding:6px 12px;border-radius:var(--radius-full);background:var(--surface);font-size:var(--body-size);line-height:var(--body-line);font-weight:var(--weight-medium);}
.tg-list{margin:0;display:flex;flex-direction:column;gap:10px;}
.tg-list div{display:flex;flex-direction:column;gap:2px;}
.tg-list dt{font-size:var(--body-size);line-height:var(--body-line);font-weight:var(--weight-semibold);}
.tg-list dd{margin:0;font-size:var(--caption-size);line-height:var(--caption-line);color:var(--text-secondary);}
.tg-takeaway{margin:0;padding:16px 20px;border-radius:var(--radius-lg);border-left:3px solid var(--accent);background:var(--surface-sunken);font-size:var(--body-size);line-height:var(--body-line);}
.tg-src{margin-top:4px;}
@media (max-width:640px){.tool-guide{padding:20px;}}