:root {
  --bg: #ffffff;
  --bg-subtle: #f7f7f5;
  --bg-rule: #f2f1ef;
  --border: #e0ddd8;
  --border-md: #ccc9c2;
  --text: #111110;
  --text-2: #4a4845;
  --text-3: #8a8782;
  --accent: #c0392b;
  --accent-bg: #fdf2f1;
  --accent-bd: #f0c4bf;
  --gold: #b07d2e;
  --gold-bg: #fdf8ee;
  --gold-bd: #e8d5a0;
  --green: #2d6a4f;
  --radius: 8px;
  --radius-sm: 4px;
  --max-w: 680px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", "Helvetica Neue", Arial, sans-serif;
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ── Page routing ─────────────────────────────── */
.page {
  display: none;
}
.page.active {
  display: block;
  animation: fadeIn 0.2s ease;
}

/* ── Navigation ───────────────────────────────── */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 4px;
  height: 50px;
}
.nav-logo {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: -0.2px;
  color: var(--text);
  margin-right: auto;
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 7px;
}
.nav-logo-mark {
  width: 22px;
  height: 22px;
  background: var(--accent);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 12px;
  font-weight: 800;
  flex-shrink: 0;
}
.nav-btn {
  background: none;
  border: none;
  color: var(--text-3);
  font-family: inherit;
  font-size: 13px;
  font-weight: 500;
  padding: 5px 11px;
  border-radius: 6px;
  cursor: pointer;
  transition:
    color 0.12s,
    background 0.12s;
}
.nav-btn:hover {
  color: var(--text);
  background: var(--bg-subtle);
}
.nav-btn.active {
  color: var(--text);
  background: var(--bg-rule);
  font-weight: 600;
}

/* ── Search ───────────────────────────────────── */
.search-wrap {
  padding: 16px 20px 0;
  max-width: var(--max-w);
  margin: 0 auto;
}
.search-box {
  position: relative;
}
.search-box input {
  width: 100%;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 9px 36px 9px 36px;
  color: var(--text);
  font-family: inherit;
  font-size: 13.5px;
  outline: none;
  transition:
    border-color 0.15s,
    box-shadow 0.15s;
}
.search-box input::placeholder {
  color: var(--text-3);
}
.search-box input:focus {
  border-color: var(--text-3);
  background: var(--bg);
  box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.06);
}
.search-icon {
  position: absolute;
  left: 11px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-3);
  font-size: 18px;
  pointer-events: none;
}
.search-clear {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-3);
  font-size: 18px;
  cursor: pointer;
  line-height: 1;
  display: none;
  padding: 2px 4px;
}
.search-clear:hover {
  color: var(--text);
}

/* ── Search results ───────────────────────────── */
#search-results {
  display: none;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 8px 20px 20px;
}
#search-results.visible {
  display: block;
}
.search-count {
  color: var(--text-3);
  font-size: 12px;
  margin-bottom: 8px;
}
.search-hit {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 14px;
  margin-bottom: 6px;
  cursor: pointer;
  transition:
    border-color 0.12s,
    background 0.12s;
  background: var(--bg);
}
.search-hit:hover {
  border-color: var(--border-md);
  background: var(--bg-subtle);
}
.search-hit-tag {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 3px;
}
.search-hit-title {
  font-weight: 600;
  font-size: 13.5px;
  margin-bottom: 2px;
}
.search-hit-snippet {
  font-size: 12.5px;
  color: var(--text-2);
  line-height: 1.5;
}
mark {
  background: #fff3a8;
  color: #6b5600;
  border-radius: 2px;
  padding: 0 1px;
}

/* ── Content ──────────────────────────────────── */
.content {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 16px 20px 80px;
}

/* ── Page header ──────────────────────────────── */
.page-header {
  padding-bottom: 12px;
  margin-bottom: 16px;
}
.page-header-eyebrow {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1.2px;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 6px;
}
.page-header h1 {
  font-size: clamp(22px, 5vw, 30px);
  font-weight: 800;
  letter-spacing: -0.8px;
  line-height: 1.1;
  margin-bottom: 8px;
}
.page-header-sub {
  font-size: 13.5px;
  color: var(--text-2);
  line-height: 1.6;
}

/* ── Basics accordion ─────────────────────────── */
/* ── Rules sub-tabs ──────────────────────────── */
.rules-tabs {
  display: flex;
  gap: 0;
  margin-bottom: 24px;
  width: 100%;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0;
}
.rules-tab {
  flex: 1;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-3);
  font-family: inherit;
  font-size: 13.5px;
  font-weight: 500;
  padding: 8px 14px;
  cursor: pointer;
  transition: color 0.12s, border-color 0.12s;
  margin-bottom: -1px;
  text-align: center;
}
.rules-tab:hover {
  color: var(--text);
}
.rules-tab.active {
  color: var(--text);
  font-weight: 600;
  border-bottom-color: var(--accent);
}
.rules-panel {
  display: none;
}
.rules-panel.active {
  display: block;
  animation: fadeIn 0.2s ease;
}

/* ── Section blocks ───────────────────────────── */
.content {
  counter-reset: section;
}
.section {
  margin-bottom: 32px;
}
.section-header {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
  counter-increment: section;
}
.section-header::before {
  content: counter(section);
  font-size: 11px;
  font-weight: 700;
  color: var(--text-3);
  letter-spacing: 0.5px;
  flex-shrink: 0;
}
.section-header h2 {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.2px;
}

/* ── Rule rows ────────────────────────────────── */
.rule-row {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 0;
  border-bottom: 1px solid var(--border);
}
.rule-row:last-child {
  border-bottom: none;
}
.rule-label {
  padding: 11px 14px 11px 0;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  display: flex;
  align-items: flex-start;
  gap: 6px;
  padding-right: 16px;
}
.rule-body {
  padding: 11px 0;
  font-size: 13px;
  color: var(--text-2);
  line-height: 1.6;
  border-left: 1px solid var(--border);
  padding-left: 16px;
}
.rule-body p {
  margin: 0 0 10px;
}
.rule-body p:last-child {
  margin-bottom: 0;
}
.rule-body strong {
  color: var(--text);
  font-weight: 600;
}

@media (max-width: 480px) {
  .rule-row {
    grid-template-columns: 1fr;
  }
  .rule-body {
    border-left: none;
    border-top: 1px solid var(--border);
    padding-left: 0;
    padding-top: 6px;
    padding-bottom: 14px;
  }
  .rule-label {
    padding-bottom: 6px;
  }
}

/* ── Formula ──────────────────────────────────── */
.formula-inline {
  background: var(--bg-rule);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 2px 8px;
  font-family: "Courier New", monospace;
  font-size: 12px;
  color: var(--text);
  letter-spacing: 0.3px;
  white-space: nowrap;
}

/* ── Tag / badge ──────────────────────────────── */
.tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  border-radius: 3px;
  padding: 1px 7px;
  vertical-align: middle;
  margin: 0 1px;
  line-height: 1.6;
}
.tag-red {
  background: var(--accent-bg);
  color: var(--accent);
  border: 1px solid var(--accent-bd);
}
.tag-gold {
  background: var(--gold-bg);
  color: var(--gold);
  border: 1px solid var(--gold-bd);
}
.tag-gray {
  background: var(--bg-rule);
  color: var(--text-2);
  border: 1px solid var(--border);
}

.streak-tags {
  display: flex;
  flex-wrap: nowrap;
  gap: 6px;
  margin-top: 8px;
}

/* ── Tai badge ────────────────────────────────── */
.tai {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  font-size: 12px;
  font-weight: 700;
  border-radius: 3px;
  padding: 2px 8px;
  white-space: nowrap;
  flex-shrink: 0;
}
.tai-std {
  background: var(--gold-bg);
  color: var(--gold);
  border: 1px solid var(--gold-bd);
}
.tai-high {
  background: var(--accent-bg);
  color: var(--accent);
  border: 1px solid var(--accent-bd);
}

/* ── Wind table ───────────────────────────────── */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.data-table th {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--text-3);
  text-align: left;
  padding: 8px 12px;
  background: var(--bg-rule);
  border-bottom: 1px solid var(--border);
}
.data-table th:first-child {
  border-radius: var(--radius-sm) 0 0 0;
}
.data-table th:last-child {
  border-radius: 0 var(--radius-sm) 0 0;
}
.data-table td {
  padding: 9px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}
.data-table tr:last-child td {
  border-bottom: none;
}
.data-table tr:hover td {
  background: var(--bg-subtle);
}
.table-wrap {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}
.wind-sym {
  font-size: 15px;
  font-weight: 700;
  margin-right: 4px;
}

/* ── Alert box ────────────────────────────────── */
.alert {
  border-radius: var(--radius);
  padding: 12px 14px;
  margin: 8px 0;
  font-size: 13px;
  line-height: 1.6;
}
.alert-red {
  background: var(--accent-bg);
  border: 1px solid var(--accent-bd);
  color: #7a1f1a;
}
.alert-red strong {
  color: var(--accent);
}
.alert-gold {
  background: var(--gold-bg);
  border: 1px solid var(--gold-bd);
  color: #5c4010;
}
.alert strong {
  font-weight: 600;
}
.alert-title {
  font-weight: 700;
  font-size: 13px;
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 6px;
}

/* ══════════════════════════════════════
   HANDS PAGE
══════════════════════════════════════ */
.tier-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 28px 0 14px;
}
.tier-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-3);
  white-space: nowrap;
}
.tier-rule {
  flex: 1;
  height: 1px;
  background: var(--border);
}

/* ── Hand filters ────────────────────────────── */
.hand-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}
.filter-btn {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: 20px;
  color: var(--text-3);
  font-family: inherit;
  font-size: 12px;
  font-weight: 500;
  padding: 5px 12px;
  cursor: pointer;
  transition: all 0.12s;
}
.filter-btn:hover {
  color: var(--text);
  border-color: var(--border-md);
}
.filter-btn.active {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}

.hand-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 8px;
  background: var(--bg);
  transition: border-color 0.12s;
}
.hand-card:hover {
  border-color: var(--border-md);
}
.hand-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 6px;
}
.hand-name {
  font-size: 14px;
  font-weight: 700;
  line-height: 1.3;
}
.hand-chinese {
  font-size: 12px;
  color: var(--text-3);
  margin-top: 2px;
}
.hand-desc {
  font-size: 13px;
  color: var(--text-2);
  line-height: 1.6;
  margin-bottom: 10px;
}

.hand-example {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
}
.hand-example-label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 8px;
}
.hand-tiles {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
}
.meld-group {
  display: flex;
  gap: 2px;
}
.meld-sep {
  width: 1px;
  height: 34px;
  background: var(--border-md);
  margin: 0 4px;
  align-self: center;
  flex-shrink: 0;
}

/* Tile chips */
.t {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 34px;
  background: #fff;
  border: 1px solid #c8c3b8;
  border-radius: 3px;
  font-size: 11px;
  font-weight: 700;
  color: var(--text);
  box-shadow:
    0 1px 2px rgba(0, 0, 0, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
  flex-shrink: 0;
  line-height: 1;
}
.t.red {
  color: var(--accent);
}
.t.grn {
  color: var(--green);
}
.t.wind {
  color: #2b4c8c;
}
.t.flower {
  color: var(--accent);
}
.t.season {
  color: var(--green);
}
.t.pair {
  background: #f7f4ee;
  border-color: #b0ab9e;
  color: var(--text);
}
.concealed-group {
  display: flex;
  gap: 2px;
  border: 1.5px dashed var(--border-md);
  border-radius: 4px;
  padding: 3px 4px;
}

/* ══════════════════════════════════════
   CALCULATOR PAGE
══════════════════════════════════════ */
.settings-block {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 20px;
}
.settings-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 13px 16px;
  border-bottom: 1px solid var(--border);
}
.settings-row:last-child {
  border-bottom: none;
}
.settings-row:hover {
  background: var(--bg-subtle);
}
.settings-label {
  font-size: 13px;
  font-weight: 600;
}
.settings-sub {
  font-size: 12px;
  color: var(--text-3);
  margin-top: 1px;
}
.num-input {
  background: var(--bg);
  border: 1px solid var(--border-md);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  width: 76px;
  text-align: center;
  padding: 6px 8px;
  outline: none;
  transition: border-color 0.15s;
}
.num-input:focus {
  border-color: var(--text-3);
}
.num-input::-webkit-inner-spin-button,
.num-input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.num-input {
  -moz-appearance: textfield;
}

.calc-section-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 10px;
}

.tai-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}
.tai-row label {
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
}
.tai-row input[type="range"] {
  flex: 1;
  accent-color: var(--text);
  height: 2px;
}
.tai-inline-input {
  width: 56px;
  background: var(--bg);
  border: 1px solid var(--border-md);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-family: inherit;
  font-size: 18px;
  font-weight: 800;
  text-align: center;
  padding: 4px 6px;
  outline: none;
  letter-spacing: -0.5px;
  transition: border-color 0.15s;
  -moz-appearance: textfield;
}
.tai-inline-input::-webkit-inner-spin-button,
.tai-inline-input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}
.tai-inline-input:focus {
  border-color: var(--text-3);
}

.win-type-row {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
}
.win-type-btn {
  flex: 1;
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-2);
  font-family: inherit;
  font-size: 13px;
  font-weight: 600;
  padding: 9px 8px;
  cursor: pointer;
  transition: all 0.12s;
}
.win-type-btn.sel {
  background: var(--text);
  border-color: var(--text);
  color: var(--bg);
}

.dealer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-2);
  margin-bottom: 16px;
}
.toggle {
  position: relative;
  width: 40px;
  height: 22px;
}
.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}
.toggle-slider {
  position: absolute;
  inset: 0;
  background: var(--border-md);
  border-radius: 11px;
  cursor: pointer;
  transition: background 0.2s;
}
.toggle-slider::after {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  left: 3px;
  top: 3px;
  background: white;
  border-radius: 50%;
  transition: transform 0.2s;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}
.toggle input:checked + .toggle-slider {
  background: var(--text);
}
.toggle input:checked + .toggle-slider::after {
  transform: translateX(18px);
}

.calc-result {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  margin-bottom: 12px;
  background: var(--bg-subtle);
}
.calc-amount {
  font-size: 44px;
  font-weight: 800;
  letter-spacing: -2px;
  line-height: 1;
  margin-bottom: 6px;
}
.calc-sublabel {
  font-size: 12.5px;
  color: var(--text-3);
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.calc-cell {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  background: var(--bg);
}
.calc-cell-val {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.calc-cell-lbl {
  font-size: 11px;
  color: var(--text-3);
  margin-top: 2px;
}

hr.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 24px 0;
}

/* ── Animations ──────────────────────────────── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}