/* WhichModel — minimal, serious, responsive.
   Light base with a restrained accent; no external assets or webfonts. */

:root {
  --bg: #f7f8f9;
  --surface: #ffffff;
  --surface-alt: #f2f4f6;
  --border: #e2e6ea;
  --border-strong: #cfd6dd;
  --text: #14181c;
  --text-muted: #5c6771;
  --text-faint: #8a949d;
  --accent: #1d4ed8;
  --accent-dark: #1738a8;
  --accent-soft: #eef2ff;
  --gold: #b8860b;
  --radius: 10px;
  --radius-sm: 6px;
  --shadow-sm: 0 1px 2px rgba(16, 24, 32, .06);
  --shadow: 0 2px 8px rgba(16, 24, 32, .07);
  --maxw: 940px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1216;
    --surface: #171b21;
    --surface-alt: #1e242c;
    --border: #262d36;
    --border-strong: #333c47;
    --text: #e8ecf0;
    --text-muted: #a3adb8;
    --text-faint: #7b858f;
    --accent: #6d94ff;
    --accent-dark: #8fadff;
    --accent-soft: #1a2540;
    --gold: #d6a531;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, .3);
    --shadow: 0 2px 10px rgba(0, 0, 0, .35);
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--accent); color: #fff; padding: 10px 16px; z-index: 100;
}
.skip-link:focus { left: 12px; top: 12px; }

/* ---------- header ---------- */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 18px 0;
}
.brand { display: flex; align-items: center; gap: 9px; }
.brand-mark { color: var(--accent); font-size: 1.05rem; }
.brand-text { font-weight: 650; font-size: 1.1rem; letter-spacing: -0.01em; }
.tagline { margin: 3px 0 0 26px; color: var(--text-muted); font-size: .875rem; }

/* ---------- intro ---------- */
.intro { padding: 44px 0 26px; }
h1 {
  margin: 0 0 12px;
  font-size: clamp(1.6rem, 4.4vw, 2.15rem);
  line-height: 1.22;
  letter-spacing: -0.021em;
  font-weight: 660;
}
.lede { margin: 0; color: var(--text-muted); max-width: 62ch; font-size: 1.02rem; }

/* ---------- form ---------- */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow-sm);
}
.label {
  display: block; font-weight: 600; font-size: .875rem;
  margin-bottom: 8px; color: var(--text);
}
textarea {
  width: 100%;
  padding: 13px 14px;
  font: inherit;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  resize: vertical;
  min-height: 84px;
}
textarea:focus-visible {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
textarea::placeholder { color: var(--text-faint); }

.examples { display: flex; flex-wrap: wrap; gap: 7px; align-items: center; margin: 14px 0 4px; }
.examples-label { font-size: .8rem; color: var(--text-faint); margin-right: 2px; }
.chip {
  font: inherit; font-size: .8rem;
  padding: 5px 11px;
  background: var(--surface-alt);
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  cursor: pointer;
  transition: background .13s, color .13s, border-color .13s;
}
.chip:hover { background: var(--accent-soft); color: var(--accent); border-color: var(--accent); }
.chip:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.actions { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin-top: 18px; }
.btn-primary {
  font: inherit; font-weight: 600; font-size: .95rem;
  padding: 11px 22px;
  color: #fff; background: var(--accent);
  border: none; border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background .13s;
}
.btn-primary:hover:not(:disabled) { background: var(--accent-dark); }
.btn-primary:disabled { opacity: .6; cursor: progress; }
.btn-primary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
@media (prefers-color-scheme: dark) { .btn-primary { color: #0f1216; } }
.hint { font-size: .8rem; color: var(--text-faint); }

/* ---------- status ---------- */
.status { margin: 22px 0 0; padding: 14px 16px; border-radius: var(--radius-sm); font-size: .92rem; }
.status.loading { background: var(--accent-soft); color: var(--accent); border: 1px solid var(--border); }
.status.error { background: #fdeded; color: #a3231d; border: 1px solid #f5c6c3; }
@media (prefers-color-scheme: dark) {
  .status.error { background: #331a1a; color: #ffb3ae; border-color: #582a2a; }
}

/* ---------- results ---------- */
.results { margin: 34px 0 0; }
.result-head { margin-bottom: 18px; }
.result-head h2 { margin: 0; font-size: .8rem; text-transform: uppercase; letter-spacing: .09em; color: var(--text-faint); font-weight: 640; }
.result-summary { margin: 6px 0 0; font-size: 1.12rem; font-weight: 550; line-height: 1.4; }
.tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 11px; }
.tag {
  font-size: .76rem; font-weight: 550;
  padding: 3px 9px; border-radius: 4px;
  background: var(--accent-soft); color: var(--accent);
  border: 1px solid var(--border);
}
.tag-cap { background: var(--surface-alt); color: var(--text-muted); font-family: var(--mono); }

.cards { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}
.card::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 3px;
  background: var(--border-strong);
}
.card-1::before { background: var(--accent); }
.card-2::before { background: #17976b; }
.card-3::before { background: var(--gold); }

.card-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 12px; flex-wrap: wrap; }
.slot {
  font-size: .73rem; font-weight: 700; text-transform: uppercase; letter-spacing: .075em;
  color: var(--text-faint);
}
.card-1 .slot { color: var(--accent); }
.card-2 .slot { color: #17976b; }
.card-3 .slot { color: var(--gold); }

.model-name { margin: 5px 0 3px; font-size: 1.16rem; font-weight: 640; letter-spacing: -0.012em; line-height: 1.3; }
.model-id { font-family: var(--mono); font-size: .795rem; color: var(--text-muted); word-break: break-all; }

.tier {
  font-family: var(--mono); font-weight: 700; font-size: .9rem;
  padding: 4px 10px; border-radius: var(--radius-sm);
  white-space: nowrap;
  background: var(--surface-alt); border: 1px solid var(--border);
}
.tier-1 { color: #15803d; } .tier-2 { color: #0d7490; }
.tier-3 { color: #b45309; } .tier-4 { color: #b3261e; }
@media (prefers-color-scheme: dark) {
  .tier-1 { color: #62d68f; } .tier-2 { color: #58c8e3; }
  .tier-3 { color: #f0b355; } .tier-4 { color: #ff8f88; }
}

.ratings { display: flex; flex-wrap: wrap; gap: 8px 22px; margin: 15px 0 0; padding: 13px 0 0; border-top: 1px solid var(--border); }
.rating { display: flex; align-items: baseline; gap: 7px; font-size: .855rem; }
.rating-label { color: var(--text-muted); }
.rating-stars { letter-spacing: -1px; font-size: .82rem; }
.rating-num { color: var(--text-faint); font-size: .78rem; font-variant-numeric: tabular-nums; }

.prices { display: flex; flex-wrap: wrap; gap: 8px 22px; margin-top: 11px; font-size: .885rem; }
.price strong { font-variant-numeric: tabular-nums; font-weight: 620; }
.price span { color: var(--text-muted); }

.badges { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 11px; }
.badge {
  font-size: .74rem; padding: 2px 8px; border-radius: 4px;
  background: var(--surface-alt); color: var(--text-muted); border: 1px solid var(--border);
}

.why { margin: 14px 0 0; padding: 12px 14px; background: var(--surface-alt); border-radius: var(--radius-sm); font-size: .9rem; color: var(--text-muted); line-height: 1.55; }
.why-label { font-weight: 650; color: var(--text); font-style: italic; margin-right: 4px; }

.tip {
  margin: 20px 0 0; padding: 17px 19px;
  background: var(--accent-soft);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  font-size: .92rem; line-height: 1.6;
}
.tip strong { display: block; margin-bottom: 5px; font-size: .78rem; text-transform: uppercase; letter-spacing: .07em; color: var(--accent); }
.tip code { font-family: var(--mono); font-size: .84em; background: var(--surface); padding: 1px 5px; border-radius: 3px; border: 1px solid var(--border); word-break: break-all; }

.meta { margin: 15px 0 0; font-size: .78rem; color: var(--text-faint); }

/* ---------- explainer / legend ---------- */
.explainer, .legend { margin: 50px 0 0; }
.explainer h2, .legend h2 { font-size: 1.16rem; font-weight: 640; margin: 0 0 16px; letter-spacing: -0.012em; }
.explainer-grid { display: grid; gap: 20px; grid-template-columns: 1fr; }
.explainer-grid h3 { font-size: .935rem; font-weight: 620; margin: 0 0 6px; }
.explainer-grid p { margin: 0; font-size: .885rem; color: var(--text-muted); }

.details { margin-top: 22px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 14px 17px; }
.details summary { cursor: pointer; font-weight: 570; font-size: .91rem; }
.details summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.details p { margin: 11px 0 0; font-size: .875rem; color: var(--text-muted); }

.legend-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 9px; grid-template-columns: 1fr; }
.legend-list li { display: flex; align-items: center; gap: 11px; font-size: .885rem; color: var(--text-muted); }
.legend-note { margin: 14px 0 0; font-size: .81rem; color: var(--text-faint); }

/* ---------- footer ---------- */
.site-footer { margin-top: 58px; padding: 22px 0; border-top: 1px solid var(--border); background: var(--surface); }
.site-footer p { margin: 0; font-size: .81rem; color: var(--text-faint); }
.site-footer a { color: var(--text-muted); }
a { color: var(--accent); }

/* ---------- responsive ---------- */
@media (min-width: 640px) {
  .legend-list { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 760px) {
  .explainer-grid { grid-template-columns: repeat(3, 1fr); }
  .panel { padding: 26px; }
  .card { padding: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}