/* Hallmark · custom direction (QuantDrill: light-first, premium, technical) · genre: modern-minimal · signature: the live problem set huge in Geist Mono, and the share card · shape: tool-first */
/* critique: one action per screen, one signal green, bezel shells with concentric radii; nothing moves during play except the clock */

@import url("tokens.css");

/* ---------- Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { overflow-x: clip; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; }
h1, h2, h3 { font-weight: 600; margin: 0; overflow-wrap: break-word; min-width: 0; }
p { margin: 0; }
button, input, select { font: inherit; color: inherit; }
[hidden] { display: none !important; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; transition: none; }
.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;
}
.skip:focus { position: fixed; z-index: 99; top: 8px; left: 8px; width: auto; height: auto; clip: auto; padding: 8px 12px; background: var(--surface); border-radius: 8px; }
.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--header-bg);
  backdrop-filter: blur(16px) saturate(160%);
  -webkit-backdrop-filter: blur(16px) saturate(160%);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--s-5);
  display: flex;
  align-items: center;
  gap: var(--s-3);
  height: 60px;
}
.brand { display: inline-flex; align-items: center; margin-right: auto; border-radius: 8px; }
.brand svg { height: 26px; width: auto; }
.logo-ring { stroke: var(--ink); }
.logo-tail { stroke: var(--accent); }
.logo-quant { fill: var(--ink); }
.logo-drill { fill: var(--logo-drill); }
.nav { display: flex; align-items: center; gap: 2px; }
.nav a {
  text-decoration: none;
  font-size: 14px;
  color: var(--ink-2);
  padding: 8px 12px;
  border-radius: var(--r-pill);
  transition: color 150ms ease, background-color 150ms ease;
}
.nav a[aria-current="page"] { color: var(--ink); background: var(--surface-2); }
@media (hover: hover) and (pointer: fine) { .nav a:hover { color: var(--ink); background: var(--surface-2); } }
.icon-btn {
  display: inline-grid; place-items: center;
  width: 38px; height: 38px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink-2);
  cursor: pointer;
  transition: transform 140ms var(--ease-out), color 150ms ease, border-color 150ms ease;
}
.icon-btn svg { width: 18px; height: 18px; }
.icon-btn:active { transform: scale(0.94); }
@media (hover: hover) and (pointer: fine) { .icon-btn:hover { color: var(--ink); border-color: var(--line-strong); } }
.theme-icon-dark { display: none; }
:root[data-theme="dark"] .theme-icon-dark { display: block; }
:root[data-theme="dark"] .theme-icon-light { display: none; }

/* ---------- Layout ---------- */
.page {
  flex: 1;
  width: 100%;
  max-width: calc(var(--app-width) + 2 * var(--s-5));
  margin-inline: auto;
  padding: var(--s-7) var(--s-5) var(--s-8);
}
.page.wide { max-width: calc(var(--container) + 2 * var(--s-5)); }
.shell {
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: var(--r-outer);
  padding: var(--gap-shell);
  box-shadow: var(--shadow-md);
}
.panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-inner);
  padding: var(--s-5);
}
.panel + .panel { margin-top: var(--gap-shell); }
.section { margin-top: var(--s-6); }
.section-head { display: flex; justify-content: space-between; align-items: baseline; gap: var(--s-3); margin-bottom: var(--s-3); flex-wrap: wrap; }
.section-head h2 { font-size: 18px; letter-spacing: -0.015em; }
.muted { color: var(--ink-3); font-size: 14px; }
.sub-h { font-size: 14px; font-weight: 600; color: var(--ink-2); margin-bottom: var(--s-3); }

/* ---------- Buttons ---------- */
.btn {
  position: relative;
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  height: 48px;
  padding: 0 22px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.005em;
  text-decoration: none;
  cursor: pointer;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  white-space: nowrap;
  transition: transform 140ms var(--ease-out), background-color 160ms ease, border-color 160ms ease, box-shadow 200ms ease;
}
.btn:active { transform: scale(0.97); }
.btn svg { width: 18px; height: 18px; }
.btn-secondary { background: var(--surface); border-color: var(--line-strong); color: var(--ink); }
@media (hover: hover) and (pointer: fine) { .btn-secondary:hover { border-color: var(--ink-3); } }
.btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
  overflow: hidden;
  isolation: isolate;
  box-shadow: 0 1px 0 var(--inset-hi) inset, 0 8px 24px -8px var(--accent-glow);
}
.btn-primary::before {
  content: "";
  position: absolute; inset: 0; z-index: -1;
  background: linear-gradient(105deg, transparent 30%, var(--sheen) 50%, transparent 70%);
  transform: translateX(-120%);
  animation: sheen 3.4s var(--ease-in-out) 1s infinite;
}
@keyframes sheen { 0% { transform: translateX(-120%); } 45%, 100% { transform: translateX(120%); } }
@media (hover: hover) and (pointer: fine) {
  .btn-primary:hover { background: var(--accent-hover); box-shadow: 0 1px 0 var(--inset-hi) inset, 0 12px 30px -8px var(--accent-glow); }
}
.btn-lg { height: 58px; padding: 0 32px; font-size: 17px; }
.kbd {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  padding: 2px 7px;
  border-radius: 6px;
  background: var(--kbd-bg);
}
@media (pointer: coarse) { .kbd { display: none; } }
.link-quiet {
  background: none; border: 0; padding: 4px 2px;
  color: var(--ink-3); font-size: 14px;
  text-decoration: underline; text-decoration-color: var(--line-strong); text-underline-offset: 3px;
  cursor: pointer; border-radius: 4px;
  transition: color 150ms ease;
}
@media (hover: hover) and (pointer: fine) { .link-quiet:hover { color: var(--ink); } }

/* ---------- Home ---------- */
.hero h1 {
  font-size: clamp(2.1rem, 6.4vw, 3.6rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  max-width: 14ch;
}
.hero p { margin-top: var(--s-3); font-size: 18px; color: var(--ink-2); max-width: 46ch; }
.start-row { margin-top: var(--s-5); display: flex; align-items: center; flex-wrap: wrap; gap: var(--s-3); }
.status-row { margin-top: var(--s-4); display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 12px;
  border-radius: var(--r-pill);
  background: var(--surface);
  border: 1px solid var(--line);
  font-size: 13px;
  color: var(--ink-2);
}
.chip strong { color: var(--ink); font-weight: 600; }
.chip svg { width: 15px; height: 15px; flex-shrink: 0; }
.chip .flame { color: var(--flame); }
.chip.is-risk { border-color: var(--flame); }
.chip.is-done { color: var(--accent-strong); }
.chip.is-done svg { color: var(--accent-strong); }
.rank-bar { width: 56px; height: 5px; border-radius: var(--r-pill); background: var(--surface-2); overflow: hidden; }
.rank-bar span { display: block; height: 100%; width: 100%; background: var(--accent); transform-origin: left center; }
.goal-ring { width: 18px; height: 18px; }
.goal-ring .track { stroke: var(--surface-2); }
.goal-ring .val { stroke: var(--accent); }

.settings-summary {
  margin-top: var(--s-6);
  display: flex; align-items: center; flex-wrap: wrap; gap: 6px var(--s-3);
  font-size: 14px; color: var(--ink-3);
}
.settings-summary .mono { color: var(--ink-2); font-size: 13px; }
.settings-wrap { margin-top: var(--s-4); }

.ops { display: grid; gap: var(--gap-row); }
.op { border-radius: var(--r-row); padding: 14px 16px; background: var(--surface); border: 1px solid transparent; transition: background-color 150ms ease, border-color 150ms ease; }
.op:has(input[type="checkbox"]:checked) { background: var(--surface-2); border-color: var(--line); }
.op-head { display: flex; align-items: center; gap: 12px; cursor: pointer; font-weight: 500; }
.op-sym { font-family: var(--font-mono); color: var(--ink-3); margin-left: auto; font-size: 15px; }
.op-body { margin-top: 10px; padding-left: 34px; color: var(--ink-3); font-size: 14px; display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.op:has(input[type="checkbox"]:not(:checked)) .op-body { opacity: 0.45; }
.check {
  appearance: none; -webkit-appearance: none; margin: 0;
  width: 22px; height: 22px; border-radius: 7px;
  border: 1.5px solid var(--line-strong);
  background: var(--surface);
  display: grid; place-items: center;
  cursor: pointer; flex-shrink: 0;
  transition: background-color 150ms ease, border-color 150ms ease, transform 120ms var(--ease-out);
}
.check::after {
  content: ""; width: 10px; height: 6px;
  border-left: 2px solid var(--accent-ink); border-bottom: 2px solid var(--accent-ink);
  transform: translateY(-1px) rotate(-45deg) scale(0.6); opacity: 0;
  transition: transform 160ms var(--ease-out), opacity 120ms ease;
}
.check:checked { background: var(--accent); border-color: var(--accent); }
.check:checked::after { opacity: 1; transform: translateY(-1px) rotate(-45deg) scale(1); }
.check:active { transform: scale(0.92); }
.range-group { display: inline-flex; align-items: center; gap: 6px; }
.num-input {
  width: 72px; height: 36px; padding: 0 10px;
  border-radius: var(--r-control);
  border: 1px solid var(--line-strong);
  background: var(--surface);
  font-family: var(--font-mono); font-size: 14px; text-align: right; font-variant-numeric: tabular-nums;
  color: var(--ink);
  transition: border-color 150ms ease, box-shadow 150ms ease;
}
.num-input:focus-visible, .select:focus-visible, .text-input:focus-visible { outline: none; border-color: var(--accent-strong); box-shadow: 0 0 0 3px var(--accent-glow); }
.num-input[aria-invalid="true"] { border-color: var(--warn); }
.paren { font-family: var(--font-mono); color: var(--ink-3); }
.settings-foot { display: flex; align-items: center; flex-wrap: wrap; gap: var(--s-3) var(--s-5); justify-content: space-between; }
.field-inline { display: inline-flex; align-items: center; gap: 10px; font-weight: 500; font-size: 15px; }
.select {
  height: 38px; padding: 0 34px 0 12px;
  border-radius: var(--r-control);
  border: 1px solid var(--line-strong);
  background-color: var(--surface);
  font-size: 14px;
  appearance: none; -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--ink-3) 50%), linear-gradient(135deg, var(--ink-3) 50%, transparent 50%);
  background-position: calc(100% - 17px) 16px, calc(100% - 12px) 16px;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  cursor: pointer;
}
.toggle-row { display: inline-flex; align-items: center; gap: 10px; font-size: 15px; font-weight: 500; cursor: pointer; }
.form-error { color: var(--warn); font-size: 14px; margin-top: var(--s-3); }

/* ---------- Game ---------- */
.game .panel { padding: var(--s-5) var(--s-5) var(--s-5); }
.game-bar { display: flex; justify-content: space-between; align-items: center; gap: var(--s-3); font-size: 14px; color: var(--ink-3); }
.game-bar .score-now strong { font-family: var(--font-mono); font-variant-numeric: tabular-nums; color: var(--ink); font-size: 17px; font-weight: 600; margin-left: 6px; }
.bar-right { display: inline-flex; align-items: center; gap: 8px; }
.ghost { font-family: var(--font-mono); font-variant-numeric: tabular-nums; font-size: 12px; color: var(--ink-3); }
.ghost.is-ahead { color: var(--accent-strong); }
.timer {
  font-family: var(--font-mono); font-variant-numeric: tabular-nums;
  font-size: 13px; color: var(--ink-3);
  padding: 3px 9px; border-radius: var(--r-pill); background: var(--surface-2);
  transition: color 150ms ease;
}
.timer.is-low { color: var(--warn); }
.progress { margin-top: 12px; height: 3px; background: var(--line); border-radius: var(--r-pill); overflow: hidden; }
.progress span { display: block; height: 100%; background: var(--ink); transform-origin: left center; }
.progress.is-low span { background: var(--warn); }
.problem-wrap { min-height: 290px; display: grid; place-items: center; align-content: center; gap: var(--s-5); padding-block: var(--s-6); }
.problem {
  font-family: var(--font-mono);
  font-size: clamp(2.6rem, 11vw, 5.25rem);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  text-align: center;
}
.problem .opr { color: var(--ink-3); margin-inline: 0.18em; }
.answer {
  width: min(280px, 100%);
  height: 64px;
  border-radius: 16px;
  border: 1.5px solid var(--line-strong);
  background: var(--surface-2);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 30px; font-weight: 500;
  font-variant-numeric: tabular-nums;
  color: var(--ink);
  caret-color: var(--accent-strong);
  transition: border-color 120ms ease, box-shadow 120ms ease;
}
.answer:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-glow); }
.answer.flash { border-color: var(--accent); background: var(--accent-soft); }
.game-foot { display: flex; justify-content: center; flex-wrap: wrap; gap: var(--s-2) var(--s-5); margin-top: var(--s-3); }
.keypad { display: none; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; width: min(380px, 100%); margin: var(--s-3) auto 0; }
.keypad button {
  height: 58px;
  border-radius: 16px;
  border: 1px solid var(--line);
  background: var(--surface-2);
  font-family: var(--font-mono); font-size: 24px; font-weight: 500;
  color: var(--ink);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  transition: transform 90ms var(--ease-out), background-color 90ms ease;
}
.keypad button.is-pressed, .keypad button:active { transform: scale(0.95); background: var(--line); }
.keypad .key-fn { font-family: var(--font-sans); font-size: 15px; color: var(--ink-2); }
.keypad svg { width: 22px; height: 22px; margin: auto; }
.use-keypad .keypad { display: grid; }
.use-keypad .problem-wrap { min-height: 0; padding-block: var(--s-5) var(--s-2); gap: var(--s-4); }
.use-keypad .answer { height: 56px; }

/* Time's up */
.timesup { text-align: center; padding: var(--s-7) var(--s-5); display: grid; gap: var(--s-3); justify-items: center; }
.timesup .label { color: var(--ink-3); font-size: 15px; }
.timesup .big { font-family: var(--font-mono); font-size: clamp(4rem, 16vw, 7rem); font-weight: 500; letter-spacing: -0.05em; line-height: 1; font-variant-numeric: tabular-nums; }
.timesup .btn { margin-top: var(--s-4); }

/* Phones: the round takes the whole screen */
@media (max-width: 640px) {
  body.is-playing .site-header, body.is-playing .site-footer { display: none; }
  body.is-playing .page { padding-top: var(--s-3); padding-bottom: var(--s-3); }
  body.is-playing .shell { box-shadow: none; }
}

/* ---------- Results ---------- */
.result-top { display: grid; gap: var(--s-2); }
.result-label { color: var(--ink-3); font-size: 15px; }
.result-score-row { display: flex; align-items: flex-end; gap: var(--s-4); flex-wrap: wrap; }
.result-score {
  font-family: var(--font-mono);
  font-size: clamp(4.5rem, 17vw, 8.5rem);
  font-weight: 500;
  letter-spacing: -0.05em;
  line-height: 0.92;
  font-variant-numeric: tabular-nums;
}
.rank-chip { margin-bottom: 10px; }
.badges { display: flex; flex-wrap: wrap; gap: 8px; }
.badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px;
  border-radius: var(--r-pill);
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-size: 13px; font-weight: 600;
  animation: badge-in 420ms var(--ease-out) both;
}
.badge svg { width: 14px; height: 14px; }
.badge.neutral { background: var(--surface-2); color: var(--ink-2); }
.badge:nth-child(2) { animation-delay: 80ms; }
.badge:nth-child(3) { animation-delay: 160ms; }
.badge:nth-child(n+4) { animation-delay: 240ms; }
@keyframes badge-in { from { opacity: 0; transform: scale(0.94); } to { opacity: 1; transform: none; } }
.result-meta { color: var(--ink-2); font-size: 16px; }
.result-meta strong { color: var(--ink); }
.actions { margin-top: var(--s-4); display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-3); }

.insight { display: flex; gap: var(--s-3); align-items: flex-start; }
.insight-icon { width: 32px; height: 32px; border-radius: 10px; background: var(--accent-soft); color: var(--accent-strong); display: grid; place-items: center; flex-shrink: 0; }
.insight-icon svg { width: 18px; height: 18px; }
.insight h2 { font-size: 13px; font-weight: 500; color: var(--ink-3); }
.insight p { margin-top: 2px; font-size: 16px; color: var(--ink); }

.tiles { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--gap-shell); }
@media (min-width: 720px) { .tiles { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.tile { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-inner); padding: var(--s-4) var(--s-5); min-width: 0; }
.tile-label { font-size: 13px; color: var(--ink-3); }
.tile-value { margin-top: 4px; font-family: var(--font-mono); font-size: 30px; font-weight: 500; letter-spacing: -0.03em; font-variant-numeric: tabular-nums; line-height: 1.1; }
.tile-value small { font-size: 16px; color: var(--ink-3); letter-spacing: 0; margin-left: 2px; }
.tile-note { font-size: 12px; color: var(--ink-3); margin-top: 2px; }

/* ranked weak spots */
.weak-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 6px; counter-reset: weak; }
.weak-list li {
  display: grid; grid-template-columns: 28px minmax(0, 1fr) auto; align-items: center; gap: var(--s-3);
  padding: 12px 14px;
  border-radius: var(--r-row);
  background: var(--surface-2);
  font-size: 15px;
}
.weak-rank { font-family: var(--font-mono); font-weight: 600; color: var(--ink-3); }
.weak-list li:first-child .weak-rank { color: var(--flame); }
.weak-name { min-width: 0; }
.weak-name small { display: block; color: var(--ink-3); font-size: 12px; }
.weak-val { font-family: var(--font-mono); font-variant-numeric: tabular-nums; color: var(--ink-2); }

/* heatmap */
.seg { display: inline-flex; padding: 3px; border-radius: var(--r-pill); background: var(--surface-2); border: 1px solid var(--line); }
.seg button {
  border: 0; background: none; cursor: pointer;
  padding: 5px 14px; border-radius: var(--r-pill);
  font-size: 13px; font-weight: 500; color: var(--ink-3);
  transition: background-color 150ms ease, color 150ms ease;
}
.seg button[aria-pressed="true"] { background: var(--surface); color: var(--ink); box-shadow: var(--shadow-sm); }
.heatmap { position: relative; }
.heat-grid {
  display: grid;
  grid-template-columns: 34px repeat(10, minmax(0, 1fr));
  gap: 3px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-3);
}
.heat-grid .hc {
  aspect-ratio: 1.9;
  border-radius: 5px;
  background: var(--heat-none);
  border: 0;
  padding: 0;
  cursor: default;
}
.heat-grid .hc[data-v] { cursor: pointer; }
.heat-grid .rh { display: flex; align-items: center; justify-content: flex-end; padding-right: 6px; }
.heat-grid .ch { text-align: center; padding-top: 4px; font-size: 10px; }
.heat-legend { display: flex; align-items: center; gap: 8px; margin-top: var(--s-3); font-size: 12px; color: var(--ink-3); flex-wrap: wrap; }
.heat-legend .ramp { display: flex; gap: 2px; }
.heat-legend .ramp span { width: 18px; height: 10px; border-radius: 3px; }
.heat-note { margin-top: var(--s-2); }

/* charts */
.chart { position: relative; width: 100%; }
.chart svg { width: 100%; height: auto; overflow: visible; }
.chart .grid-line { stroke: var(--line); stroke-width: 1; }
.chart .axis-label { fill: var(--ink-3); font-family: var(--font-sans); font-size: 11px; }
.chart .series { fill: none; stroke: var(--accent-strong); stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.chart .avg { fill: none; stroke: var(--ink-3); stroke-width: 2; stroke-dasharray: 5 4; stroke-linecap: round; }
.chart .area { fill: var(--accent); opacity: 0.10; }
.chart .dot { fill: var(--accent-strong); stroke: var(--surface); stroke-width: 2; }
.chart .last-dot { fill: var(--accent); stroke: var(--surface); stroke-width: 3; }
.chart .best-dot { fill: var(--surface); stroke: var(--accent-strong); stroke-width: 2; }
.chart .cross { stroke: var(--ink-3); stroke-width: 1; stroke-dasharray: 3 3; }
.chart .hover-dot { fill: var(--accent-strong); stroke: var(--surface); stroke-width: 2; }
.chart .hit { fill: transparent; cursor: crosshair; }
.chart-legend { display: flex; flex-wrap: wrap; gap: var(--s-4); font-size: 13px; color: var(--ink-2); margin-bottom: var(--s-3); }
.chart-legend span { display: inline-flex; align-items: center; gap: 6px; }
.chart-legend i { width: 18px; height: 0; border-top: 2px solid var(--accent-strong); display: inline-block; }
.chart-legend i.dash { border-top: 2px dashed var(--ink-3); }
.tooltip {
  position: absolute; top: 0; left: 0;
  pointer-events: none;
  background: var(--tooltip-bg); color: var(--tooltip-ink);
  padding: 8px 10px; border-radius: 10px;
  font-size: 12px; line-height: 1.4; white-space: nowrap;
  box-shadow: var(--shadow-md);
  opacity: 0;
  transition: opacity 120ms ease;
  z-index: 3;
}
.tooltip.is-on { opacity: 1; }
.tooltip strong { font-family: var(--font-mono); font-size: 14px; }
details.table-view { margin-top: var(--s-3); }
details.table-view summary { cursor: pointer; color: var(--ink-3); font-size: 14px; border-radius: 4px; width: fit-content; }
.data-table { width: 100%; border-collapse: collapse; margin-top: var(--s-3); font-size: 14px; }
.data-table th { text-align: left; font-weight: 500; color: var(--ink-3); padding: 8px 6px; border-bottom: 1px solid var(--line); }
.data-table td { padding: 8px 6px; border-bottom: 1px solid var(--line); font-variant-numeric: tabular-nums; }
.table-scroll { max-height: 320px; overflow: auto; }

/* ad slot: takes no space until an ad fills it */
.ad-slot { margin-top: var(--s-7); }
.ad-slot:empty { display: none; }
.ad-slot .ad-label { font-size: 12px; color: var(--ink-3); margin: 0 0 6px 4px; }
.ad-slot .adsbygoogle { display: block; }

/* ---------- Stats page ---------- */
.page-head { display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: var(--s-4); margin-bottom: var(--s-5); }
.page-head h1 { font-size: clamp(2rem, 5vw, 2.75rem); letter-spacing: -0.035em; line-height: 1.05; }
.page-head p { color: var(--ink-2); margin-top: 6px; }
.rank-ladder { list-style: none; margin: var(--s-4) 0 0; padding: 0; display: grid; gap: 4px; }
.rank-ladder li { display: flex; justify-content: space-between; gap: var(--s-3); padding: 8px 12px; border-radius: var(--r-row); font-size: 14px; color: var(--ink-3); }
.rank-ladder li.is-reached { color: var(--ink); }
.rank-ladder li.is-current { background: var(--accent-soft); color: var(--accent-strong); font-weight: 600; }
.rank-ladder .mono { font-size: 13px; }
.rank-head { display: flex; align-items: center; justify-content: space-between; gap: var(--s-3); flex-wrap: wrap; }
.rank-name { font-size: 26px; font-weight: 600; letter-spacing: -0.03em; }
.rank-progress { margin-top: var(--s-3); height: 8px; border-radius: var(--r-pill); background: var(--surface-2); overflow: hidden; }
.rank-progress span { display: block; height: 100%; width: 100%; background: var(--accent); transform-origin: left center; }
.goal-form { display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-3); margin-top: var(--s-3); }
.text-input {
  width: 96px; height: 44px; padding: 0 12px;
  border-radius: var(--r-control);
  border: 1px solid var(--line-strong);
  background: var(--surface);
  font-family: var(--font-mono); font-size: 16px; font-variant-numeric: tabular-nums;
}
.goal-form .btn { height: 44px; padding: 0 18px; font-size: 14px; }
.milestones { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--gap-shell); }
@media (min-width: 720px) { .milestones { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
.ms { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-inner); padding: 14px 16px; display: flex; gap: 12px; align-items: flex-start; min-width: 0; }
.ms-icon { width: 30px; height: 30px; border-radius: 9px; display: grid; place-items: center; background: var(--surface-2); color: var(--ink-3); flex-shrink: 0; }
.ms-icon svg { width: 16px; height: 16px; }
.ms.is-on .ms-icon { background: var(--accent); color: var(--accent-ink); }
.ms h3 { font-size: 14px; font-weight: 600; }
.ms p { font-size: 12px; color: var(--ink-3); margin-top: 2px; }
.ms:not(.is-on) h3 { color: var(--ink-3); }
.danger-zone { display: flex; flex-wrap: wrap; gap: var(--s-3); align-items: center; justify-content: space-between; margin-top: var(--s-7); }
.btn-danger { color: var(--warn); }
.empty { text-align: center; padding: var(--s-7) var(--s-5); display: grid; gap: var(--s-4); justify-items: center; }
.empty h2 { font-size: 22px; letter-spacing: -0.02em; }
.empty p { color: var(--ink-2); max-width: 40ch; }

/* ---------- Prose ---------- */
.prose { max-width: var(--measure); }
.prose h1 { font-size: clamp(2rem, 5vw, 3rem); letter-spacing: -0.035em; line-height: 1.05; }
.prose .lede { font-size: 19px; color: var(--ink-2); margin-top: var(--s-3); }
.prose h2 { font-size: 22px; letter-spacing: -0.02em; margin-top: var(--s-7); }
.prose p, .prose ul, .prose ol { margin-top: var(--s-3); color: var(--ink-2); }
.prose li { margin-top: 6px; }
.prose strong { color: var(--ink); font-weight: 600; }
.prose .eg { font-family: var(--font-mono); font-size: 0.92em; background: var(--surface-2); border: 1px solid var(--line); padding: 1px 6px; border-radius: 6px; color: var(--ink); }
.prose a { text-decoration-color: var(--line-strong); text-underline-offset: 3px; }
.callout { margin-top: var(--s-5); padding: var(--s-4) var(--s-5); border-radius: var(--r-inner); background: var(--surface); border: 1px solid var(--line); }
.prose-cta { margin-top: var(--s-7); }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); padding-block: var(--s-6); font-size: 14px; color: var(--ink-3); }
.footer-inner { max-width: var(--container); margin-inline: auto; padding-inline: var(--s-5); display: flex; flex-wrap: wrap; gap: var(--s-3) var(--s-5); align-items: center; justify-content: space-between; }
.footer-links { display: flex; flex-wrap: wrap; gap: var(--s-2) var(--s-5); }
.footer-links a, .footer-links button { color: var(--ink-3); text-decoration: none; background: none; border: 0; padding: 0; cursor: pointer; font-size: 14px; border-radius: 4px; }
@media (hover: hover) and (pointer: fine) { .footer-links a:hover, .footer-links button:hover { color: var(--ink); } }

/* ---------- Welcome sheet (first visit) ---------- */
.welcome { position: fixed; z-index: 50; left: 16px; right: 16px; bottom: 16px; max-width: 420px; animation: sheet-in 380ms var(--ease-out) both; }
@keyframes sheet-in { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: none; } }
.welcome .shell { box-shadow: var(--shadow-lg); }
.welcome-head { display: flex; align-items: center; gap: 12px; }
.welcome-head svg { width: 36px; height: 36px; }
.welcome h2 { font-size: 18px; letter-spacing: -0.015em; }
.welcome p { margin-top: 10px; font-size: 14px; color: var(--ink-2); }
.welcome .btn { width: 100%; margin-top: var(--s-4); }
.welcome .fine { margin-top: 10px; font-size: 12px; color: var(--ink-3); }
.welcome .fine a { color: var(--ink-3); text-underline-offset: 3px; }
.welcome-more { margin-top: 4px; display: grid; justify-items: start; gap: 8px; }
.welcome-more .link-quiet { font-size: 12px; }
.welcome-more .btn { width: auto; height: 40px; font-size: 14px; margin-top: 0; }

/* ---------- Toast ---------- */
.toast {
  position: fixed; z-index: 60; left: 50%; bottom: 24px;
  transform: translateX(-50%);
  background: var(--tooltip-bg); color: var(--tooltip-ink);
  padding: 10px 16px; border-radius: var(--r-pill);
  font-size: 14px; box-shadow: var(--shadow-lg);
  animation: toast-in 260ms var(--ease-out) both;
}
@keyframes toast-in { from { opacity: 0; transform: translate(-50%, 8px); } to { opacity: 1; transform: translate(-50%, 0); } }

/* ---------- Small screens ---------- */
@media (max-width: 640px) {
  .page { padding-top: var(--s-5); padding-bottom: var(--s-7); }
  .header-inner { padding-inline: var(--s-4); }
  .nav a { padding: 8px 9px; }
  .panel { padding: var(--s-4); }
  .op-body { padding-left: 0; }
  .num-input { width: 64px; }
  .hero p { font-size: 17px; }
  .start-row .btn-lg { flex: 1 1 100%; }
  .actions .btn { flex: 1 1 auto; }
  .heat-grid { grid-template-columns: 26px repeat(10, minmax(0, 1fr)); gap: 2px; font-size: 10px; }
  .heat-grid .hc { aspect-ratio: 1.15; }
}
@media (max-width: 380px) {
  .brand svg { height: 22px; }
  .nav a { padding: 8px 7px; font-size: 13px; }
}
@media (max-height: 700px) and (max-width: 640px) {
  .use-keypad .problem-wrap { padding-block: var(--s-3) 0; gap: var(--s-3); }
  .keypad button { height: 52px; }
  .problem { font-size: clamp(2.4rem, 10vw, 4rem); }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .btn-primary::before { animation: none; transform: translateX(-120%); }
  .badge, .welcome, .toast { animation: none; }
  .btn:active, .icon-btn:active, .check:active, .keypad button:active, .keypad button.is-pressed { transform: none; }
}
@media (prefers-reduced-transparency: reduce) {
  .site-header { background: var(--bg); backdrop-filter: none; -webkit-backdrop-filter: none; }
}

/* stats tiles: three across on wide screens */
@media (min-width: 720px) { .tiles.tiles-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); } }

/* ---------- Install to home screen ---------- */
.install { position: fixed; z-index: 50; left: 12px; right: 12px; bottom: 12px; max-width: 440px; margin-inline: auto; animation: sheet-in 380ms var(--ease-out) both; }
.install .shell { box-shadow: var(--shadow-lg); }
.install-head { display: flex; gap: 14px; align-items: center; }
.install-head img { width: 48px; height: 48px; border-radius: 12px; flex-shrink: 0; }
.install h2 { font-size: 17px; letter-spacing: -0.015em; }
.install p { margin-top: 2px; font-size: 14px; color: var(--ink-2); }
.install-steps { margin: var(--s-4) 0 0; padding-left: 20px; font-size: 15px; color: var(--ink-2); display: grid; gap: 6px; }
.install-steps strong { color: var(--ink); }
.install-steps svg { display: inline-block; width: 16px; height: 16px; vertical-align: -3px; color: var(--accent-strong); }
.install .btn-primary { width: 100%; margin-top: var(--s-4); }
.install-later { display: block; margin: 8px auto 0; font-size: 13px; }
@media (prefers-reduced-motion: reduce) { .install { animation: none; } }

/* ---------- Multiple-choice tests ---------- */
.mc-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; width: min(460px, 100%); }
.mc-opt {
  display: flex; align-items: center; gap: 12px;
  min-height: 60px; padding: 0 16px;
  border-radius: 16px; border: 1px solid var(--line-strong); background: var(--surface-2);
  font-family: var(--font-mono); font-size: 22px; font-weight: 500; font-variant-numeric: tabular-nums;
  color: var(--ink); cursor: pointer; text-align: left;
  touch-action: manipulation; -webkit-tap-highlight-color: transparent;
  transition: transform 90ms var(--ease-out), background-color 90ms ease, border-color 120ms ease;
}
.mc-opt:active { transform: scale(0.97); background: var(--line); }
@media (hover: hover) and (pointer: fine) { .mc-opt:hover { border-color: var(--accent-strong); } }
.mc-key { font-family: var(--font-sans); font-size: 12px; font-weight: 600; color: var(--ink-3); width: 22px; height: 22px; border-radius: 6px; background: var(--surface); border: 1px solid var(--line); display: grid; place-items: center; flex-shrink: 0; }
@media (pointer: coarse) { .mc-key { display: none; } }
.is-mc .problem { font-size: clamp(2.2rem, 8vw, 4rem); }
.skip-btn { margin-top: 4px; }

/* ---------- Quiet clear-data control ---------- */
.data-zone { margin-top: var(--s-8); text-align: center; }
.data-zone .link-quiet { font-size: 12px; }
.confirm-box { margin: var(--s-3) auto 0; max-width: 420px; text-align: left; }
.confirm-box p { font-size: 14px; color: var(--ink-2); }
.confirm-box .row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: var(--s-3); }
.confirm-box .btn { height: 40px; font-size: 14px; padding: 0 16px; }

/* ---------- Landing and hub pages ---------- */
.crumbs { display: flex; flex-wrap: wrap; gap: 8px; font-size: 13px; color: var(--ink-3); margin-bottom: var(--s-4); }
.crumbs a { color: var(--ink-3); text-decoration: none; border-radius: 4px; }
@media (hover: hover) and (pointer: fine) { .crumbs a:hover { color: var(--ink); } }
.landing-cta { margin-top: var(--s-5); display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-3) var(--s-4); }
.prose .muted { font-size: 14px; }
.faq { margin-top: var(--s-3); display: grid; gap: var(--gap-row); }
.faq details { background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-row); padding: 14px 16px; }
.faq summary { cursor: pointer; font-weight: 600; color: var(--ink); list-style-position: outside; }
.faq details p { margin-top: 8px; }
.related { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.related li { margin: 0; }
.related a { display: inline-flex; padding: 8px 14px; border-radius: var(--r-pill); border: 1px solid var(--line-strong); background: var(--surface); text-decoration: none; color: var(--ink); font-size: 14px; transition: border-color 150ms ease; }
@media (hover: hover) and (pointer: fine) { .related a:hover { border-color: var(--accent-strong); } }
.table-facts { max-width: 320px; }
.table-facts td:last-child { font-family: var(--font-mono); color: var(--ink); }
.mini-grid { margin-top: var(--s-4); display: grid; grid-template-columns: repeat(auto-fill, minmax(96px, 1fr)); gap: 8px; }
.mini-card { display: grid; gap: 2px; padding: 12px 14px; border-radius: var(--r-row); background: var(--surface); border: 1px solid var(--line); text-decoration: none; color: var(--ink); transition: border-color 150ms ease, transform 140ms var(--ease-out); }
.mini-card strong { font-family: var(--font-mono); font-size: 18px; }
.mini-card span { font-size: 12px; color: var(--ink-3); }
.mini-card:active { transform: scale(0.97); }
@media (hover: hover) and (pointer: fine) { .mini-card:hover { border-color: var(--accent-strong); } }
.hub-h { font-size: 18px; letter-spacing: -0.015em; margin: var(--s-6) 0 var(--s-3); }
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 280px), 1fr)); gap: 10px; }
.card-link { display: grid; gap: 6px; align-content: start; padding: var(--s-5); border-radius: var(--r-inner); background: var(--surface); border: 1px solid var(--line); text-decoration: none; color: var(--ink); box-shadow: var(--shadow-sm); transition: border-color 150ms ease, transform 140ms var(--ease-out), box-shadow 200ms ease; }
.card-link strong { font-size: 18px; letter-spacing: -0.015em; }
.card-link span:last-child { font-size: 14px; color: var(--ink-2); }
.card-tag { justify-self: start; font-size: 12px; font-family: var(--font-mono); color: var(--accent-strong); background: var(--accent-soft); padding: 2px 8px; border-radius: var(--r-pill); }
.card-link:active { transform: scale(0.98); }
@media (hover: hover) and (pointer: fine) { .card-link:hover { border-color: var(--accent-strong); box-shadow: var(--shadow-md); } }
@media (prefers-reduced-motion: reduce) { .card-link:active, .mini-card:active { transform: none; } }