/* Dark, mobile-first look modelled on the wellness-app reference mockup:
   near-black page, rounded dark cards, coral active state, pastel-gradient hero.

   Every color lives in a token below. Rules further down use var(--token) only, so retheming means
   editing this block (and the chart palette in .viz). tests/tests.html fails if a raw color appears elsewhere. */

/* ---- tokens ---- */
:root {
  /* surfaces and ink */
  --page: #0c0c0d;
  --shell: #111113;
  --card: #1a1a1c;
  --card-2: #232326;
  --tabbar: #08080a;
  --tip: #2a2a2d;
  --border: #2b2b2e;
  --border-strong: #3a3a3e;
  --text: #f4f4f2;
  --text-2: #bab9b5;
  --muted: #8a8985;
  --neutral-mark: #5b5a57;          /* "nothing special" marks: unselected card edge, legend key */

  /* brand and state */
  --accent: #ff7a5c;
  --accent-soft: rgba(255, 122, 92, 0.13);
  --accent-ink: #0c0c0d;            /* text on an accent fill */
  --focus: #7fb2ff;
  --critical: #ff6b6b;

  /* the pastel hero card and what sits on it */
  --hero: linear-gradient(135deg, #f7c6e0 0%, #fbe9a8 35%, #b8f2d8 68%, #c9c2ff 100%);
  --hero-ink: #14141a;
  --hero-line: rgba(20, 20, 26, 0.55);   /* outlines of controls on the hero */
  --hero-wash: rgba(20, 20, 26, 0.08);   /* hover fill for controls on the hero */
  --pill: #0c0c0d;                       /* the black pill button */
  --pill-ink: #ffffff;

  /* chart chrome */
  --grid: #2c2c2a;
  --baseline: #383835;

  --radius: 20px;
  --radius-sm: 12px;
  color-scheme: dark;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--page);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.app {
  max-width: 480px;
  min-height: 100vh;
  margin: 0 auto;
  background: var(--shell);
  position: relative;
}

/* ---- header ---- */
.top {
  display: flex; align-items: center; gap: 12px;
  padding: 20px 20px 8px;
}
.logo { width: 40px; height: 40px; flex: none; }
.top .kicker { font-size: 0.75rem; color: var(--muted); line-height: 1.1; }
.top > div { min-width: 0; }
.top .name { font-size: 1.0625rem; font-weight: 700; line-height: 1.2; }
.chip {
  margin-left: auto; flex: none; white-space: nowrap;
  font-size: 0.75rem; font-weight: 600;
  padding: 6px 12px; border-radius: 999px;
  border: 1px solid var(--border-strong); color: var(--text-2);
}

main { padding: 12px 20px 112px; }
.view[hidden] { display: none !important; }

h1 { font-size: 1.5rem; line-height: 1.2; margin: 8px 0 6px; }
h2 { font-size: 1rem; margin: 0 0 12px; }
.lede { color: var(--text-2); margin: 0 0 20px; }
.section-title { display: flex; justify-content: space-between; align-items: baseline;
  font-size: 0.95rem; font-weight: 600; margin: 24px 2px 10px; }

/* ---- cards ---- */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  margin-bottom: 14px;
}

.hero {
  background: var(--hero);
  color: var(--hero-ink);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 14px;
}
.hero .eyebrow { font-size: 0.8125rem; opacity: 0.7; }
.hero .big { font-size: 1.5rem; font-weight: 700; line-height: 1.2; margin: 2px 0 14px; }
.hero .small { font-size: 0.8125rem; opacity: 0.7; margin: 10px 0 0; }

.empty { text-align: center; color: var(--muted); padding: 28px 16px; }
.empty b { display: block; color: var(--text-2); margin-bottom: 4px; }

/* ---- forms ---- */
.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.grid .full { grid-column: 1 / -1; }
@media (max-width: 400px) { .grid { grid-template-columns: 1fr; } }

label, .label { display: block; font-size: 0.8125rem; font-weight: 600; color: var(--text-2); margin-bottom: 6px; }
.hint { color: var(--muted); font-size: 0.8125rem; margin-top: 4px; }

input, select {
  width: 100%;
  padding: 12px 14px;
  font: inherit;
  color: var(--text);
  background: var(--card-2);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
}
input::placeholder { color: var(--muted); }
input:focus-visible, select:focus-visible, button:focus-visible, a:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}
[aria-invalid="true"] { border-color: var(--critical); }
.error { color: var(--critical); font-size: 0.8125rem; margin-top: 4px; }
.error:empty { display: none; }

.seg { display: flex; gap: 8px; flex-wrap: wrap; }
.seg label, .modality label {
  display: flex; align-items: center; gap: 10px;
  margin: 0; font-weight: 500; font-size: 0.9375rem; color: var(--text);
  padding: 11px 14px;
  background: var(--card-2);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
}
.seg input, .modality input { width: auto; margin: 0; accent-color: var(--accent); }
.seg label:has(input:checked), .modality label:has(input:checked) {
  background: var(--accent-soft); border-color: var(--accent);
}
.modality { display: grid; gap: 8px; }

/* ---- buttons ---- */
button {
  font: inherit; font-weight: 600; cursor: pointer;
  padding: 12px 20px; border-radius: 999px; border: 1px solid transparent;
}
button[disabled], button[aria-disabled="true"] { opacity: 0.45; cursor: not-allowed; }
.primary { background: var(--accent); color: var(--accent-ink); }
.pill { background: var(--pill); color: var(--pill-ink); padding: 10px 18px; font-size: 0.9375rem; }
.ghost { background: transparent; color: var(--text); border-color: var(--border-strong); }
.danger { background: transparent; color: var(--critical); border-color: var(--border-strong); }
.actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 8px; }

.note { color: var(--muted); font-size: 0.8125rem; }

dl.summary { display: grid; grid-template-columns: max-content 1fr; gap: 8px 18px; margin: 0; }
dl.summary dt { color: var(--muted); font-size: 0.875rem; }
dl.summary dd { margin: 0; overflow-wrap: anywhere; }

/* ---- bottom tab bar ---- */
.tabbar {
  position: fixed; bottom: 0; left: 50%; transform: translateX(-50%);
  width: min(100%, 480px);
  display: flex; justify-content: space-around;
  padding: 10px 12px calc(10px + env(safe-area-inset-bottom));
  background: var(--tabbar);
  border-top: 1px solid var(--border);
  border-radius: 22px 22px 0 0;
}
.tabbar[hidden] { display: none; }
.tabbar a {
  flex: 1; display: flex; flex-direction: column; align-items: center; gap: 2px;
  padding: 6px 0; color: var(--muted); text-decoration: none; font-size: 0.6875rem;
}
.tabbar svg { width: 24px; height: 24px; }
.tabbar a[aria-current="page"] { color: var(--accent); }

/* ---- tick box ---- tick box themed through four variables: on dark cards it is an accent tick box; the hero
   overrides the variables so it matches the black pill button there. */
.check {
  --check-line: var(--border-strong); --check-fill: transparent; --check-on: var(--accent); --check-tick: var(--accent-ink);
  display: flex; align-items: center; gap: 10px; margin: 6px 0;
  font-size: 0.9375rem; font-weight: 600; color: inherit; cursor: pointer;
}
.check input[type="checkbox"] {
  appearance: none; position: relative; flex: none; width: 22px; height: 22px; margin: 0; padding: 0; cursor: pointer;
  border-radius: 6px; background: var(--check-fill); border: 2px solid var(--check-line);
  transition: background 0.12s, border-color 0.12s;
}
.check input[type="checkbox"]::after {
  content: ""; position: absolute; inset: 0; margin: auto; width: 14px; height: 14px;
  background: var(--check-tick); transform: scale(0); transition: transform 0.12s;
  -webkit-mask: center / contain no-repeat url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12.5l4.5 4.5L19 7'/%3E%3C/svg%3E");
  mask: center / contain no-repeat url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12.5l4.5 4.5L19 7'/%3E%3C/svg%3E");
}
.check input[type="checkbox"]:checked { background: var(--check-on); border-color: var(--check-on); }
.check input[type="checkbox"]:checked::after { transform: scale(1); }
.check input[type="checkbox"]:disabled { opacity: 0.5; cursor: default; }

/* ---- timeline and results ---- */
.timeline-legend { display: flex; flex-wrap: wrap; gap: 6px 16px; margin: 0 0 12px; font-size: 0.75rem; color: var(--text-2); }
.timeline-legend[hidden] { display: none; }
.lg { display: inline-flex; align-items: center; gap: 6px; }
.lg-key { display: inline-block; width: 4px; height: 14px; border-radius: 2px; }
.lg-key.used { background: var(--accent); }
.lg-key.none { background: var(--neutral-mark); }
.card.result.vns-used { border-left: 4px solid var(--accent); }
.card.result.vns-none { border-left: 4px solid var(--neutral-mark); }
.chip-on { color: var(--accent); border-color: var(--accent); }
.result-head { display: flex; align-items: center; flex-wrap: wrap; gap: 6px 10px; margin-bottom: 10px; }
.result-time { font-weight: 600; }
.pill-tag { font-size: 0.6875rem; font-weight: 600; padding: 3px 10px; border-radius: 999px; background: var(--card-2); color: var(--text-2); }
.pill-tag.vns-tag.used { background: var(--accent-soft); color: var(--accent); }
.pill-tag.vns-tag.none { color: var(--muted); }
.result-row { display: flex; justify-content: space-between; gap: 12px; margin: 8px 0 4px; }
.result-label { color: var(--muted); font-size: 0.875rem; }
.result-val { font-weight: 700; }
.bar { height: 8px; border-radius: 999px; background: var(--card-2); overflow: hidden; }
.bar-fill { height: 100%; border-radius: 999px; background: var(--hero); }
.result-meta { margin-top: 12px; color: var(--muted); font-size: 0.75rem; }
.result-error { border-color: var(--border-strong); }
.result-msg { margin: 0; color: var(--critical); font-size: 0.9375rem; }
.vns-toggle { margin-top: 12px; padding-top: 10px; border-top: 1px solid var(--border); }
.vns-toggle .check { margin: 0; font-size: 0.8125rem; font-weight: 500; color: var(--text-2); }
.vns-extra { margin-top: 10px; }
.vns-feedback { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; font-size: 0.8125rem; color: var(--text-2); }
.fb-btn { font-size: 0.75rem; font-weight: 500; color: var(--text-2); background: transparent; border: 1px solid var(--border-strong); padding: 4px 14px; }
.fb-btn[aria-pressed="true"] { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.vns-outcome { margin: 8px 0 0; font-size: 0.75rem; color: var(--muted); }

/* (i) menus: a short explanation behind a small summary line */
.info-menu { margin: 0 0 14px; font-size: 0.75rem; color: var(--muted); }
.info-menu[hidden] { display: none; }
.info-menu summary { display: inline-flex; align-items: center; gap: 8px; cursor: pointer; }
.info-i { display: inline-flex; align-items: center; justify-content: center; width: 16px; height: 16px; border: 1px solid var(--muted); border-radius: 50%; font: italic 700 0.6875rem/1 Georgia, serif; }
.info-body { margin-top: 8px; padding: 10px 12px; border-radius: var(--radius-sm); background: var(--card-2); color: var(--text-2); }
.info-body p { margin: 0 0 8px; line-height: 1.5; }
.info-body p:last-child { margin-bottom: 0; }

/* ---- switch ---- */
.switch { display: flex; align-items: center; gap: 12px; margin: 0; font-size: 1rem; font-weight: 600; color: var(--text); cursor: pointer; }
.switch input[type="checkbox"] {
  appearance: none; width: 46px; height: 28px; flex: none; margin: 0;
  border-radius: 999px; background: var(--card-2); border: 1px solid var(--border-strong);
  position: relative; cursor: pointer; transition: background 0.15s;
}
.switch input[type="checkbox"]::after {
  content: ""; position: absolute; top: 3px; left: 3px; width: 20px; height: 20px;
  border-radius: 50%; background: var(--text-2); transition: transform 0.15s;
}
.switch input[type="checkbox"]:checked { background: var(--accent); border-color: var(--accent); }
.switch input[type="checkbox"]:checked::after { transform: translateX(18px); background: var(--accent-ink); }

details.card summary { cursor: pointer; font-weight: 600; }

textarea {
  width: 100%; padding: 12px 14px; font: 0.8125rem/1.4 ui-monospace, monospace;
  color: var(--text); background: var(--card-2); border: 1px solid transparent; border-radius: var(--radius-sm);
}
textarea:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
.pill-btn { background: var(--accent); color: var(--accent-ink); }

/* ---- studies ---- */
.study summary { display: flex; align-items: baseline; gap: 8px; }
.study-cite { margin: 10px 0 4px; }
.digest { margin-top: 10px; }
.digest-line { margin: 0 0 10px; font-size: 0.875rem; line-height: 1.5; color: var(--text-2); overflow-wrap: anywhere; }
.digest-line b { color: var(--text); }

.opt { color: var(--muted); font-size: 0.8125rem; font-weight: 400; }

.del-btn { margin-left: auto; font: inherit; font-size: 0.75rem; color: var(--muted); background: none; border: 1px solid var(--border-strong); border-radius: 999px; padding: 4px 12px; cursor: pointer; }
.del-btn:hover, .del-btn:focus-visible { color: var(--critical); border-color: var(--critical); }
.del-btn[hidden] { display: none; }

.key-link { margin: 0 0 8px; }
.key-link a { color: var(--accent); }

/* ---- biometrics: combined metric cards and charts ---- */
.viz {
  --s1: #3987e5; --s2: #d95926; --s3: #199e70;          /* categories, in fixed order */
  --ord1: #184f95; --ord2: #256abf; --ord3: #3987e5; --ord4: #86b6ef;   /* stress levels, light = more stress */
  --gray: #898781; --band: rgba(57, 135, 229, 0.35);
}
.metric { display: block; }
.m-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; }
.m-main { display: flex; flex-direction: column; min-width: 0; }
.m-second { text-align: right; align-items: flex-end; }
.m-label { font-size: 0.75rem; color: var(--muted); }
.m-value { font-size: 1.75rem; font-weight: 700; line-height: 1.2; margin-top: 2px; color: var(--muted); }
.m-sub { font-size: 0.75rem; color: var(--muted); }
.m-spark, .m-spark-row { display: flex; align-items: center; justify-content: flex-end; gap: 10px; }
.m-spark-row { margin-top: 8px; font-size: 0.75rem; color: var(--muted); }
.m-spark-row:empty, .m-spark:empty, .m-chart:empty, .m-detail:empty { display: none; }
.spark { width: 96px; height: 32px; flex: none; }
.spark-line { fill: none; stroke: var(--s1); stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.spark-dot { fill: var(--s1); stroke: var(--card); stroke-width: 2; }
.m-chart { margin-top: 14px; }
.m-detail { margin: 10px 0 0; font-size: 0.8125rem; color: var(--text-2); }
.viz-cap { margin: 14px 0 0; font-size: 0.75rem; color: var(--muted); }
.viz-svg { width: 100%; height: auto; display: block; overflow: visible; }
.viz-axis { fill: var(--muted); font-size: 10px; }
.viz-value { fill: var(--text); font-size: 11px; font-weight: 700; }
.viz-grid { stroke: var(--grid); stroke-width: 1; }
.viz-base { stroke: var(--baseline); stroke-width: 1; }
.viz-track { fill: var(--card-2); }
.viz-band { fill: var(--band); }
.viz-tick { stroke: var(--text-2); stroke-width: 2; stroke-linecap: round; }
.viz-dot { fill: var(--s1); stroke: var(--card); stroke-width: 2; }
.viz-dot-ink { fill: var(--text); }
.viz-col { fill: var(--s1); }
.viz-ref { stroke: var(--text); stroke-width: 1; opacity: 0.6; }
.viz-hit { fill: transparent; }
.viz-level:hover { filter: brightness(1.15); }
svg [tabindex]:focus-visible, .viz-seg:focus-visible, .viz-hfill:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
.viz-stack { display: flex; gap: 2px; height: 16px; }
.viz-seg { min-width: 3px; }
.viz-seg:first-child { border-radius: 4px 0 0 4px; }
.viz-seg:last-child { border-radius: 0 4px 4px 0; }
.viz-seg:only-child { border-radius: 4px; }
.viz-legend { display: flex; flex-wrap: wrap; gap: 6px 14px; margin-top: 10px; font-size: 0.75rem; color: var(--text-2); }
.viz-legend-item { display: inline-flex; align-items: center; gap: 6px; }
.viz-key { display: inline-block; flex: none; }
.viz-key-swatch { width: 10px; height: 10px; border-radius: 3px; }
.viz-key-dot { width: 10px; height: 10px; border-radius: 50%; }
.viz-key-line { width: 14px; height: 2px; }
.viz-key-tick { width: 2px; height: 12px; }
.viz-hbars { margin-top: 6px; }
.viz-hrow { display: grid; grid-template-columns: 58px 1fr 44px; align-items: center; gap: 10px; margin-top: 8px; font-size: 0.8125rem; }
.viz-hlabel { color: var(--text-2); }
.viz-htrack { display: block; height: 12px; background: var(--card-2); border-radius: 4px; }
.viz-hfill { display: block; height: 100%; border-radius: 0 4px 4px 0; min-width: 3px; }
.viz-hval { text-align: right; font-weight: 600; }
.viz-tip { position: fixed; z-index: 50; display: flex; flex-direction: column; pointer-events: none; padding: 6px 10px; border-radius: 10px; background: var(--tip); border: 1px solid var(--border-strong); font-size: 0.75rem; color: var(--text-2); }
.viz-tip[hidden] { display: none; }
.viz-tip strong { color: var(--text); font-size: 0.875rem; }
.viz-table summary { margin-top: 10px; font-size: 0.75rem; color: var(--muted); cursor: pointer; }
.viz-table table { width: 100%; margin-top: 6px; border-collapse: collapse; font-size: 0.75rem; }
.viz-table th { text-align: left; font-weight: 400; color: var(--muted); padding: 3px 0; }
.viz-table td { text-align: right; color: var(--text); padding: 3px 0; }
.explain { margin-top: 12px; padding-top: 10px; border-top: 1px solid var(--border); }
.explain summary { cursor: pointer; font-size: 0.875rem; font-weight: 600; }
.explain p { margin: 10px 0 0; font-size: 0.8125rem; color: var(--text-2); line-height: 1.5; }
.explain-links a { margin-right: 16px; color: var(--accent); }