:root {
  --bg: #18181c;
  --surface: #202026;
  --surface-2: #2c2c34;
  --surface-3: #383842;
  --border: #3a3a44;
  --text: #e4e4ea;
  --text-2: #b8b8c6;
  --text-3: #8a8a9c;
  --accent: #4a5bdc;
  --accent-border: #6a7bff;
  --highlight: #ffd23c;
  --live: #ff5a5a;
  --panel-w: 380px;
  --header-h: 49px;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--header-h); }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 13px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

button, .button {
  font: inherit;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 10px;
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
}
button:hover, .button:hover { background: var(--surface-3); }
button:focus-visible, canvas:focus-visible, .button:focus-visible { outline: 2px solid var(--accent-border); outline-offset: 1px; }
button.primary { background: var(--accent); border-color: var(--accent-border); color: #fff; }
button.primary:hover { background: #5a6bec; }
.button.ghost { background: none; border-color: transparent; color: var(--text-2); }
.button.ghost:hover { color: var(--text); background: var(--surface-2); }
button.link { background: none; border: none; padding: 0; color: var(--accent-border); text-decoration: underline; }
kbd {
  font: 11px ui-monospace, Consolas, monospace;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 0 5px;
  color: var(--text);
}
button.primary kbd { background: rgba(255,255,255,.15); border-color: rgba(255,255,255,.3); color: #fff; }

/* ---- header ---- */
.top {
  position: sticky; top: 0; z-index: 10;
  height: var(--header-h);
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 0 16px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.brand { display: flex; align-items: center; gap: 8px; font-weight: 600; font-size: 15px; color: var(--text); text-decoration: none; }
.actions { display: flex; gap: 6px; }
#btn-watch.on { background: #5c2f2f; border-color: var(--live); }

/* ---- landing ---- */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 32px;
  max-width: 1240px;
  margin: 0 auto;
  padding: 36px 24px 32px;
  align-items: center;
}
.hero h1 { font-size: clamp(24px, 3.2vw, 36px); line-height: 1.15; margin: 0 0 14px; letter-spacing: -0.01em; }
.lead { font-size: 15px; color: var(--text-2); margin: 0 0 20px; max-width: 60ch; }
.lead strong { color: var(--text); }
.cta { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.cta > * { padding: 9px 14px; font-size: 14px; }
.counter { margin: 16px 0 0; color: var(--text-3); font-size: 13px; }
.counter b { color: var(--text); font-variant-numeric: tabular-nums; }
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.steps li {
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  padding: 12px 14px 13px; display: grid; grid-template-columns: auto 1fr; column-gap: 10px; row-gap: 3px;
}
.steps b {
  grid-row: span 2; width: 24px; height: 24px; border-radius: 50%;
  background: var(--accent); color: #fff; display: grid; place-items: center; font-size: 12px;
}
.steps strong { font-size: 13px; }
.steps span { color: var(--text-2); font-size: 12px; }

/* ---- the tool ---- */
#app {
  display: flex;
  height: calc(100vh - var(--header-h));
  min-height: 560px;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
#stage { position: relative; flex: 1; min-width: 0; overflow: hidden; background: #111114; }
#view { position: absolute; inset: 0; width: 100%; height: 100%; touch-action: none; display: block; }
#stage.dragging::after {
  content: "Drop to open";
  position: absolute; inset: 12px;
  border: 2px dashed var(--accent-border); border-radius: 12px;
  display: grid; place-items: center;
  background: rgba(24, 24, 28, 0.8); font-size: 18px;
}

#tour {
  position: absolute; top: 10px; left: 10px; right: 10px;
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px;
  background: rgba(20, 20, 24, 0.92); border: 1px solid var(--border); border-radius: 10px;
  padding: 7px 34px 7px 10px; color: var(--text-2); font-size: 12.5px;
}
#tour[hidden] { display: none; }
#tour .tour-label { color: #111; background: var(--highlight); border-radius: 4px; padding: 1px 6px; font-weight: 700; font-size: 11px; }
#tour button { padding: 3px 8px; font-size: 12px; }
#tour button b { color: var(--text-3); font-weight: 400; margin-right: 3px; }
#tour button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent-border); color: #fff; }
#tour button[aria-pressed="true"] b { color: #dfe3ff; }
#tour .tour-hint { color: var(--text-3); }
#tour .close { position: absolute; right: 6px; top: 6px; background: none; border: none; font-size: 16px; padding: 0 6px; color: var(--text-3); }

#empty { position: absolute; inset: 0; display: grid; place-items: center; padding: 16px; }
#empty[hidden], #loading[hidden] { display: none; }
#loading { position: absolute; inset: 0; display: grid; place-items: center; color: var(--text-3); }
.drop {
  max-width: 520px; text-align: center; padding: 32px 24px;
  border: 2px dashed var(--border); border-radius: 16px; background: var(--surface);
}
.drop h2 { font-size: 20px; margin: 0 0 10px; }
.drop p { color: var(--text-2); margin: 10px 0; }

#live-badge {
  position: absolute; bottom: 12px; left: 12px;
  background: rgba(20, 20, 24, 0.92);
  border: 1px solid var(--border); border-radius: 8px;
  padding: 4px 6px 4px 10px;
  color: var(--live); font-weight: 700; font-size: 12px;
  display: flex; align-items: center; gap: 8px;
}
#live-badge[hidden] { display: none; }
#live-badge button { padding: 3px 8px; font-size: 12px; font-weight: 400; }

#toast {
  position: absolute; left: 50%; bottom: 24px; transform: translateX(-50%);
  background: rgba(20, 20, 24, 0.95); border: 1px solid var(--border); border-radius: 8px;
  padding: 8px 14px; opacity: 0; transition: opacity .2s; pointer-events: none; max-width: 90%;
}
#toast.show { opacity: 1; }

#panel {
  width: var(--panel-w);
  flex: none;
  overflow-y: auto;
  border-left: 1px solid var(--border);
  background: var(--surface);
  padding: 12px 14px 16px;
}
#panel.hidden { display: none; }
#panel h2 {
  font-size: 10px; letter-spacing: 1px; text-transform: uppercase;
  color: var(--text-3); margin: 14px 0 6px;
}
#panel h2 span { text-transform: none; letter-spacing: 0; font-weight: 400; margin-left: 4px; }
.explain { color: var(--text-2); margin: 8px 0; }
body.noimg #panel > :not(.modes):not(#explain) { display: none; }

.modes { display: grid; grid-template-columns: 1fr 1fr; gap: 4px; }
.modes button { text-align: left; padding: 5px 8px; }
.modes button b { color: var(--text-3); font-weight: 400; margin-right: 6px; }
.modes button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent-border); color: #fff; }
.modes button[aria-pressed="true"] b { color: #dfe3ff; }

.samples p { margin: 0 0 6px; }
.samples .diff { color: var(--highlight); display: block; padding-left: 26px; }
.swatch { display: inline-block; width: 20px; height: 13px; border-radius: 3px; vertical-align: -2px; margin-right: 6px; border: 1px solid rgba(255,255,255,.2); }
.muted { color: var(--text-3); }

.ramp { display: flex; gap: 3px; }
.ramp div { flex: 1; text-align: center; font-size: 10px; color: var(--text-2); }
.ramp i { display: block; height: 30px; border-radius: 4px; margin-bottom: 2px; }
.ramp small { display: block; color: var(--text-3); }

.insights { margin: 0; padding-left: 16px; }
.insights li { margin-bottom: 4px; }

.palette .bar { display: flex; height: 20px; border-radius: 4px; overflow: hidden; margin-bottom: 6px; }
.palette .row { display: flex; align-items: center; gap: 8px; font: 11px ui-monospace, Consolas, monospace; height: 19px; white-space: pre; }
.palette .row .swatch { width: 26px; margin: 0; }
.palette .row span:last-child { margin-left: auto; color: #fff; }

.charts { display: flex; gap: 10px; margin-top: 12px; }
.charts figure { margin: 0; }
.charts figcaption { font-size: 10px; letter-spacing: 1px; text-transform: uppercase; color: var(--text-3); margin-bottom: 6px; }
#wheel { width: 150px; height: 150px; }
#hist { width: 170px; height: 150px; }

.panel-actions { display: flex; gap: 6px; margin-top: 16px; }
.panel-actions button { flex: 1; }

/* ---- below the tool ---- */
.learn, .faq { max-width: 1240px; margin: 0 auto; padding: 40px 24px 8px; }
.learn h2 { font-size: 22px; margin: 0 0 6px; }
.section-lead { color: var(--text-2); margin: 0 0 18px; font-size: 14px; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: 12px; }
.card {
  text-align: left; padding: 0; overflow: hidden; border-radius: 10px;
  background: var(--surface); border: 1px solid var(--border); display: flex; flex-direction: column;
}
.card:hover { border-color: var(--accent-border); background: var(--surface); }
.card canvas { width: 100%; aspect-ratio: 3 / 2; display: block; background: #111114; }
.card div { padding: 10px 12px 12px; }
.card strong { display: block; font-size: 13px; margin-bottom: 3px; }
.card strong b { color: var(--text-3); font-weight: 400; margin-right: 6px; }
.card span { color: var(--text-2); font-size: 12px; }
.faq { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; padding-bottom: 32px; }
.faq h3 { font-size: 14px; margin: 0 0 6px; }
.faq p { color: var(--text-2); margin: 0; }
footer { text-align: center; color: var(--text-3); padding: 18px 16px 28px; border-top: 1px solid var(--border); font-size: 12px; }

dialog {
  background: var(--surface); color: var(--text);
  border: 1px solid var(--border); border-radius: 12px;
  max-width: 640px; padding: 20px 24px;
}
dialog::backdrop { background: rgba(0, 0, 0, 0.6); }
dialog h2 { margin-top: 0; font-size: 17px; }
dialog td { padding: 4px 12px 4px 0; vertical-align: top; }
dialog td:first-child { color: var(--text-2); white-space: nowrap; }

@media (max-width: 960px) {
  .hero { grid-template-columns: 1fr; padding-top: 24px; gap: 20px; }
  .faq { grid-template-columns: 1fr; }
}
@media (max-width: 900px) {
  #app { flex-direction: column; height: auto; min-height: 0; }
  #stage { height: 70vh; min-height: 380px; flex: none; }
  #panel { width: auto; border-left: none; border-top: 1px solid var(--border); overflow: visible; }
  .top { padding: 0 12px; }
}
@media (max-width: 520px) {
  .brand span { display: none; }
  .actions button { padding: 5px 8px; }
  .steps { grid-template-columns: 1fr; }
  .hero { padding: 20px 16px; }
  .learn, .faq { padding-left: 16px; padding-right: 16px; }
  dialog td:first-child { white-space: normal; }
}
@media (hover: none) {
  .cta kbd { display: none; }   /* no keyboard shortcut hints on touch screens */
}