@import url("https://fonts.googleapis.com/css2?family=DM+Mono:wght@500&family=Manrope:wght@400;500;600;700;800&display=swap");

:root {
  --bg: #f4f2ed;
  --surface: #fbfaf7;
  --card: #ffffff;
  --ink: #191821;
  --label: #32313a;
  --muted: #706e78;
  --faint: #99969f;
  --bd: #dedbd3;
  --divider: #e8e5de;
  --accent: #6754d8;
  --accent-dark: #4937ba;
  --accent-soft: #ebe7ff;
  --mint: #b8dfce;
  --peach: #efb89d;
  --warning: #b23f50;
  --success: #2c775b;
  --control-bg: #ffffff;
  --control-bd: #cfcbc2;
  --btn-bg: #ffffff;
  --btn-hover: #f1eee8;
  --btn-bd: #d5d1c9;
  --layer-bg: #ffffff;
  --layer-bd: rgba(25, 24, 33, .16);
  --layer-empty-bg: rgba(255, 255, 255, .35);
  --layer-empty-ink: #8e8a94;
  --popover-bd: #dedbd3;
  --cbox-bd: rgba(25, 24, 33, .16);
  --cnum-bg: rgba(255, 255, 255, .9);
  --cnum-bd: rgba(25, 24, 33, .14);
  --cnum-ink: #191821;
  --rseg-bg: #faf9f6;
  --rseg-bd: rgba(25, 24, 33, .12);
  --output-bg: #211f2a;
  --output-ink: #f3f0fa;
  --shadow: 0 16px 48px rgba(31, 27, 45, .08);
  --bottleW: 68px;
  --layerH: 32px;
  --rSegH: 22px;
}

:root[data-theme="dark"] {
  --bg: #121116;
  --surface: #17161c;
  --card: #1c1b22;
  --ink: #f1eef5;
  --label: #d8d4df;
  --muted: #aaa5b2;
  --faint: #7e7988;
  --bd: #34313c;
  --divider: #302e37;
  --accent: #9989ff;
  --accent-dark: #b2a6ff;
  --accent-soft: #2b2742;
  --control-bg: #201f26;
  --control-bd: #47434f;
  --btn-bg: #211f27;
  --btn-hover: #2b2932;
  --btn-bd: #45414b;
  --layer-bg: #232129;
  --layer-bd: rgba(255, 255, 255, .15);
  --layer-empty-bg: rgba(255, 255, 255, .025);
  --layer-empty-ink: #827d8c;
  --popover-bd: #3a3741;
  --cbox-bd: rgba(255, 255, 255, .15);
  --cnum-bg: rgba(24, 23, 29, .88);
  --cnum-bd: rgba(255, 255, 255, .14);
  --cnum-ink: #f1eef5;
  --rseg-bg: #232129;
  --rseg-bd: rgba(255, 255, 255, .11);
  --output-bg: #0d0c10;
  --output-ink: #f3f0fa;
  --shadow: 0 18px 50px rgba(0, 0, 0, .28);
  color-scheme: dark;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: "Manrope", system-ui, sans-serif;
  line-height: 1.5;
  transition: background .2s ease, color .2s ease;
}

button, input, select, textarea { font: inherit; }
button { color: inherit; }
button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent) 35%, transparent);
  outline-offset: 2px;
}

.topbar {
  width: min(1440px, calc(100% - 48px));
  min-height: 76px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--bd);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -.03em;
  text-decoration: none;
}

.brand-mark {
  width: 29px;
  height: 29px;
  padding: 5px;
  display: flex;
  align-items: flex-end;
  gap: 3px;
  border: 1px solid var(--ink);
  border-radius: 8px 8px 11px 11px;
}

.brand-mark i { width: 5px; border-radius: 3px; }
.brand-mark i:nth-child(1) { height: 9px; background: var(--mint); }
.brand-mark i:nth-child(2) { height: 16px; background: var(--accent); }
.brand-mark i:nth-child(3) { height: 12px; background: var(--peach); }

.topbar-actions, .inline { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

.engine-pill, .mono-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font: 500 11px/1 "DM Mono", monospace;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.status-dot { width: 7px; height: 7px; border-radius: 50%; background: #62ad86; box-shadow: 0 0 0 4px rgba(98, 173, 134, .14); }

button {
  min-height: 42px;
  padding: 10px 16px;
  border: 1px solid var(--btn-bd);
  border-radius: 10px;
  background: var(--btn-bg);
  cursor: pointer;
  font-size: 13px;
  font-weight: 700;
  transition: transform .15s ease, background .15s ease, border-color .15s ease;
}

button:hover:not(:disabled) { background: var(--btn-hover); transform: translateY(-1px); }
button:disabled { cursor: not-allowed; opacity: .45; }
.icon-btn { width: 42px; padding: 0; font-size: 17px; }
.ghost-btn { background: transparent; }
.primary-btn { color: white; border-color: var(--accent); background: var(--accent); }
.primary-btn:hover:not(:disabled) { border-color: var(--accent-dark); background: var(--accent-dark); }
.secondary-btn { background: transparent; }
.text-btn { min-height: auto; padding: 2px 0; border: 0; background: transparent; color: var(--accent); }
.text-btn:hover:not(:disabled) { background: transparent; color: var(--accent-dark); transform: none; }

main { width: min(1440px, calc(100% - 48px)); margin: 0 auto; }

.hero {
  min-height: 410px;
  padding: 74px 4vw 62px;
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(300px, .8fr);
  align-items: end;
  gap: 64px;
}

.eyebrow, .kicker {
  margin: 0 0 12px;
  color: var(--accent);
  font: 500 11px/1.2 "DM Mono", monospace;
  letter-spacing: .12em;
  text-transform: uppercase;
}

h1, h2, p { margin-top: 0; }
h1 { max-width: 850px; margin-bottom: 24px; font-size: clamp(48px, 6.2vw, 88px); line-height: .98; letter-spacing: -.065em; }
h1 span { color: var(--accent); }
.hero-text { max-width: 690px; margin-bottom: 0; color: var(--muted); font-size: clamp(16px, 1.5vw, 20px); line-height: 1.7; }

.hero-stats { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--bd); }
.hero-stats div { padding: 22px 14px 0 0; }
.hero-stats strong { display: block; margin-bottom: 6px; font-size: 30px; line-height: 1; letter-spacing: -.05em; }
.hero-stats span { display: block; color: var(--muted); font-size: 11px; }

.workspace { display: grid; grid-template-columns: 330px minmax(0, 1fr); border: 1px solid var(--bd); background: var(--card); box-shadow: var(--shadow); }
.setup-panel { padding: 32px; border-right: 1px solid var(--bd); background: var(--surface); }
.main-panel { min-width: 0; }
.editor-card { min-height: 520px; padding: 36px 38px; }
.solve-card { padding: 28px 38px; display: flex; align-items: center; justify-content: space-between; gap: 28px; border-top: 1px solid var(--bd); background: var(--surface); }

.section-heading, .solve-copy { display: flex; align-items: flex-start; gap: 14px; }
.step-number { flex: 0 0 auto; color: var(--accent); font: 500 11px/1.2 "DM Mono", monospace; }
.section-heading h2, .solve-copy h2, .result-heading h2 { margin: 0; font-size: 21px; line-height: 1.2; letter-spacing: -.035em; }
.section-heading .kicker, .solve-copy .kicker { margin-bottom: 7px; }
.field-group { margin-top: 30px; }
.field-label-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 9px; }
label { color: var(--label); font-size: 12px; font-weight: 700; }
.field-label-row span { color: var(--faint); font: 500 10px/1 "DM Mono", monospace; text-transform: uppercase; }

input[type="number"], textarea, .ui-select {
  width: 100%;
  padding: 11px 12px;
  border: 1px solid var(--control-bd);
  border-radius: 9px;
  color: var(--ink);
  background: var(--control-bg);
}

.ui-select { min-width: 125px; }
textarea { min-height: 110px; resize: vertical; font: 12px/1.6 "DM Mono", monospace; }
.hint, .small { color: var(--muted); font-size: 11px; }
.hint { margin: 8px 0 0; line-height: 1.6; }
.divider { height: 1px; margin: 28px 0; background: var(--divider); }

.colors { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
.colors label { min-width: 0; padding: 7px 8px; display: flex; align-items: center; gap: 7px; border: 1px solid transparent; border-radius: 8px; cursor: pointer; font-size: 11px; font-weight: 600; transition: background .15s ease; }
.colors label:hover { background: var(--accent-soft); }
.colors input { accent-color: var(--accent); }
.swatch { width: 12px; height: 12px; flex: 0 0 auto; border: 1px solid rgba(0, 0, 0, .15); border-radius: 4px; }
.setup-actions { margin-top: 24px; display: grid; grid-template-columns: auto 1fr; gap: 9px; }
.warn, .ok { min-height: 0; margin-top: 10px; font-size: 12px; }
.warn { color: var(--warning); }
.ok { color: var(--success); }
.io-area { margin-top: 20px; }
.io-area[hidden] { display: none; }
.io-area label { display: block; margin-bottom: 7px; }
.io-actions { margin: 9px 0; }

.card-heading, .result-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 24px; }
.section-intro { margin: 16px 0 0 48px; color: var(--muted); font-size: 12px; }
.empty-stage { min-height: 330px; margin-top: 26px; display: flex; flex-direction: column; align-items: center; justify-content: center; color: var(--muted); text-align: center; border: 1px dashed var(--bd); background: color-mix(in srgb, var(--surface) 72%, transparent); }
.empty-stage strong, .replay-placeholder strong { margin: 15px 0 5px; color: var(--label); font-size: 13px; }
.empty-stage span, .replay-placeholder span { max-width: 310px; font-size: 11px; }
.empty-illustration { height: 68px; display: flex; align-items: flex-end; gap: 9px; }
.empty-illustration i { width: 24px; border: 2px solid var(--bd); border-top: 0; border-radius: 0 0 10px 10px; }
.empty-illustration i:nth-child(1) { height: 45px; background: linear-gradient(to top, var(--mint) 35%, transparent 35%); }
.empty-illustration i:nth-child(2) { height: 62px; background: linear-gradient(to top, var(--accent) 60%, transparent 60%); }
.empty-illustration i:nth-child(3) { height: 50px; background: linear-gradient(to top, var(--peach) 45%, transparent 45%); }

.solve-copy { min-width: 250px; }
.solve-controls { flex: 1; display: flex; align-items: flex-end; justify-content: flex-end; gap: 12px; flex-wrap: wrap; }
.mode-field label { display: block; margin-bottom: 6px; }
.check-option { min-height: 42px; padding: 0 12px; display: inline-flex; align-items: center; gap: 8px; border: 1px solid var(--btn-bd); border-radius: 10px; cursor: pointer; }
.check-option input { accent-color: var(--accent); }
.solve-btn { min-width: 150px; }

.board { margin-top: 26px; display: flex; flex-direction: column; gap: 18px; }
.board-row { display: flex; gap: 12px; justify-content: safe center; align-items: flex-end; flex-wrap: nowrap; overflow-x: auto; padding: 5px 3px 9px; scrollbar-color: var(--bd) transparent; }
.bottle { flex: 0 0 var(--bottleW); padding: 0; background: transparent; }
.bottle-title { min-height: 20px; margin-bottom: 5px; display: flex; align-items: center; justify-content: center; gap: 4px; color: var(--muted); font: 500 10px/1 "DM Mono", monospace; }
.helper-label { font-size: 8px; letter-spacing: .04em; text-transform: uppercase; }
.layers { display: flex; flex-direction: column; gap: 0; padding: 3px; overflow: hidden; border: 2px solid var(--bd); border-top-width: 1px; border-radius: 5px 5px 15px 15px; background: var(--layer-empty-bg); }
.layer { width: 100%; height: var(--layerH); min-height: var(--layerH); padding: 0; border: 0; border-radius: 0; color: transparent; background: var(--layer-bg); cursor: pointer; user-select: none; }
.layer:hover:not(:disabled) { transform: none; filter: brightness(.97); }
.layer.empty { background: transparent; }
.layer:last-child:not(.empty) { border-radius: 0 0 10px 10px; }
.layer.selected { position: relative; box-shadow: inset 0 0 0 3px var(--accent); z-index: 1; }
.layer:disabled { cursor: default; opacity: .35; }
.helper-bottle .layers { border-style: dashed; }

.fill-toolbar { margin-top: 22px; display: grid; gap: 10px; }
.fill-toolbar[hidden] { display: none; }
.fill-mode-group { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.fill-mode-label { margin-right: auto; color: var(--muted); font: 500 10px/1 "DM Mono", monospace; letter-spacing: .08em; text-transform: uppercase; }
.fill-mode-option { margin: 0; cursor: pointer; }
.fill-mode-option input { position: absolute; opacity: 0; pointer-events: none; }
.fill-mode-option span { min-height: 38px; padding: 8px 12px; display: inline-flex; align-items: center; border: 1px solid var(--btn-bd); border-radius: 9px; color: var(--muted); background: var(--btn-bg); }
.fill-mode-option input:checked + span { border-color: var(--accent); color: var(--accent); background: var(--accent-soft); }
.fill-mode-option input:focus-visible + span { outline: 3px solid color-mix(in srgb, var(--accent) 35%, transparent); outline-offset: 2px; }
.palette-panel { padding: 14px; border: 1px solid var(--bd); border-radius: 12px; background: var(--surface); }
.palette-heading { min-height: 28px; margin-bottom: 10px; display: flex; align-items: center; justify-content: space-between; gap: 10px; color: var(--label); font-size: 11px; font-weight: 700; }
.fill-palette { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 7px; }
.palette-color { min-width: 0; min-height: 46px; padding: 6px 7px; display: grid; grid-template-columns: 18px minmax(0, 1fr) 20px; align-items: center; gap: 5px; border-radius: 9px; font-size: 10px; }
.palette-color.active { border-color: var(--accent); background: var(--accent-soft); box-shadow: inset 0 0 0 1px var(--accent); }
.palette-swatch { width: 18px; height: 26px; border: 1px solid rgba(0, 0, 0, .14); border-radius: 5px 5px 7px 7px; }
.palette-name { overflow: hidden; text-align: left; text-overflow: ellipsis; white-space: nowrap; }
.palette-count { width: 20px; height: 20px; display: grid; place-items: center; border-radius: 50%; color: var(--cnum-ink); background: var(--cnum-bg); font: 700 10px/1 "DM Mono", monospace; }
.palette-complete { grid-column: 1 / -1; padding: 9px; color: var(--success); font-size: 11px; text-align: center; }
.validation-msg { margin-top: 12px; font-size: 11px; }

.results-grid { margin: 24px 0 70px; display: grid; grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr); gap: 24px; }
.result-card { min-width: 0; min-height: 420px; padding: 32px; border: 1px solid var(--bd); background: var(--card); box-shadow: var(--shadow); }
.output { min-height: 310px; max-height: 58vh; margin-top: 26px; padding: 24px; overflow: auto; border-radius: 10px; color: var(--output-ink); background: var(--output-bg); white-space: pre-wrap; font: 12px/1.8 "DM Mono", monospace; }
.replay { display: none; }
.replay-controls { margin: 26px 0 12px; display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.speed-control { margin-left: auto; display: flex; align-items: center; gap: 8px; color: var(--muted); }
.speed-control input { width: 90px; accent-color: var(--accent); }
.replay-placeholder { min-height: 310px; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; color: var(--muted); }
.play-mark { width: 48px; height: 48px; padding-left: 3px; display: grid; place-items: center; border: 1px solid var(--bd); border-radius: 50%; color: var(--accent); background: var(--surface); }
.rbottle { flex: 0 0 var(--bottleW); padding: 0; background: transparent; }
.rbottle .bottle-title { justify-content: center; }
.replay-move { color: var(--accent); font-size: 8px; text-transform: uppercase; }
.rstack { display: flex; flex-direction: column; gap: 0; padding: 3px; overflow: hidden; border: 2px solid var(--bd); border-top-width: 1px; border-radius: 5px 5px 15px 15px; background: var(--layer-empty-bg); }
.rbottle.hl .rstack { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 20%, transparent); }
.rseg { height: var(--layerH); border: 0; border-radius: 0; background: transparent; }
.rseg:last-child:not(.empty) { border-radius: 0 0 10px 10px; }

footer { width: min(1440px, calc(100% - 48px)); margin: 0 auto; padding: 28px 0 36px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-top: 1px solid var(--bd); }
footer p { margin: 0; color: var(--muted); font-size: 11px; }
.footer-brand { font-size: 14px; }
.footer-brand .brand-mark { transform: scale(.8); }

@media (max-width: 1050px) {
  .hero { grid-template-columns: 1fr; gap: 42px; }
  .hero-stats { max-width: 560px; }
  .workspace { grid-template-columns: 285px minmax(0, 1fr); }
  .solve-card { align-items: flex-start; flex-direction: column; }
  .solve-controls { justify-content: flex-start; }
  .results-grid { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  :root { --bottleW: 41px; --layerH: 30px; }
  .topbar, main, footer { width: min(100% - 16px, 1440px); }
  .topbar { min-height: 58px; }
  .engine-pill, #resetBtn { display: none; }
  .hero { min-height: auto; padding: 30px 4px 26px; }
  h1 { margin-bottom: 14px; font-size: clamp(36px, 11vw, 50px); }
  .hero-text { font-size: 14px; line-height: 1.55; }
  .hero-stats { display: none; }
  .workspace { grid-template-columns: 1fr; }
  .setup-panel { padding: 22px 14px; border-right: 0; border-bottom: 1px solid var(--bd); }
  .setup-panel .hint { display: none; }
  .field-group { margin-top: 20px; }
  .divider { margin: 20px 0; }
  .colors { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 4px; }
  .colors label { padding: 7px 4px; gap: 5px; font-size: 10px; }
  .editor-card, .solve-card, .result-card { padding: 22px 10px; }
  .card-heading { align-items: center; }
  .card-heading .secondary-btn { padding-inline: 10px; }
  .section-intro { margin-left: 0; }
  .board { gap: 13px; margin-top: 20px; }
  .board-row { gap: 4px; padding-inline: 0; }
  .bottle-title { min-height: 16px; margin-bottom: 3px; }
  .helper-label { display: none; }
  .replay-move { display: none; }
  .layers { padding: 2px; border-radius: 4px 4px 11px 11px; }
  .rstack { padding: 2px; border-radius: 4px 4px 11px 11px; }
  .fill-toolbar { margin-top: 14px; }
  .fill-mode-label { width: 100%; margin: 0 0 2px; }
  .fill-mode-option { flex: 1; }
  .fill-mode-option span { width: 100%; justify-content: center; }
  .palette-panel { position: sticky; bottom: 8px; z-index: 5; padding: 10px; box-shadow: var(--shadow); }
  .fill-palette { gap: 5px; }
  .palette-color { min-height: 44px; padding: 5px; grid-template-columns: 16px minmax(0, 1fr) 18px; gap: 3px; }
  .palette-swatch { width: 16px; height: 24px; }
  .palette-count { width: 18px; height: 18px; }
  .results-grid { gap: 14px; }
  .solve-controls { display: grid; grid-template-columns: 1fr 1fr; width: 100%; }
  .mode-field, .solve-btn { grid-column: 1 / -1; }
  .ui-select, .solve-btn { width: 100%; }
  .check-option { justify-content: center; }
  .speed-control { width: 100%; margin-left: 0; margin-top: 5px; }
  footer { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 430px) {
  .setup-actions { grid-template-columns: 1fr; }
  .result-heading { align-items: flex-start; flex-direction: column; }
  .palette-name { display: none; }
  .palette-color { grid-template-columns: 1fr 18px; }
  .palette-swatch { justify-self: center; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}