/* Tangram — warm paper, seven saturated pieces, one dark outline. */
:root {
  --bg: #efe9dd; --paper: #f6f3ec; --ink: #1c1a17; --dim: #6b655b; --line: #d8d0c0;
  --accent: #2f6fd6; --accent-ink: #ffffff; --good: #2f9e6a; --card: #fbf9f4;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; background: var(--bg); color: var(--ink); font: 15px/1.45 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
#app { max-width: 1240px; margin: 0 auto; padding: 12px 16px 24px; }
header { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; padding: 6px 0 10px; }
h1 { font-size: 26px; margin: 0; letter-spacing: 0.01em; display: flex; flex-direction: column; }
h1 .sub { font-size: 12px; font-weight: 500; color: var(--dim); letter-spacing: 0; }
.spacer { flex: 1; }
button { font: inherit; font-size: 14px; padding: 7px 12px; border-radius: 8px; border: 1px solid var(--line); background: #fff; color: var(--ink); cursor: pointer; }
button:hover { border-color: #b9ae98; background: #fffdf8; }
button.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
button.primary:hover { background: #2559b0; }
button:disabled { opacity: 0.5; cursor: default; }
main { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 16px; align-items: start; }
#stage { position: relative; background: var(--paper); border: 1px solid var(--line); border-radius: 14px; padding: 10px; }
#board { display: block; width: 100%; height: auto; border-radius: 10px; touch-action: none; cursor: grab; }
#board.dragging { cursor: grabbing; }
#banner { position: absolute; left: 50%; top: 22px; transform: translateX(-50%); background: var(--good); color: #fff; padding: 8px 16px; border-radius: 999px; font-weight: 600; box-shadow: 0 6px 18px rgba(0,0,0,0.18); pointer-events: none; }
#toolbar { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; margin-top: 10px; }
#status { margin-left: auto; color: var(--dim); }
.hint { color: var(--dim); font-size: 13px; margin: 8px 2px 0; }
aside { display: flex; flex-direction: column; gap: 12px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 12px 14px; }
.card h2 { font-size: 15px; margin: 0 0 8px; }
.row { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 8px; }
.figrow { display: flex; gap: 12px; align-items: center; }
#thumb { background: #fff; border: 1px solid var(--line); border-radius: 8px; flex: none; }
.small { font-size: 13px; color: var(--dim); margin: 4px 0; }
.mono { font-family: var(--mono); font-size: 12.5px; white-space: pre-wrap; }
footer { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; color: var(--dim); font-size: 12.5px; margin-top: 18px; padding-top: 10px; border-top: 1px solid var(--line); }
dialog { border: none; border-radius: 16px; padding: 0; max-width: min(720px, 94vw); box-shadow: 0 24px 60px rgba(0,0,0,0.3); background: var(--paper); color: var(--ink); }
dialog::backdrop { background: rgba(20, 16, 10, 0.5); }
.dlg { padding: 18px 20px 16px; max-height: 86vh; overflow: auto; }
.dlg.wide { width: min(960px, 94vw); }
dialog h2 { margin: 0 0 10px; font-size: 19px; }
dialog h3 { margin: 14px 0 6px; font-size: 15px; }
dialog p, dialog li { font-size: 14px; }
dialog table { border-collapse: collapse; width: 100%; font-size: 13px; }
dialog th, dialog td { text-align: left; padding: 4px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
dialog th { color: var(--dim); font-weight: 600; }
#lab-out { margin-top: 10px; background: #fff; border: 1px solid var(--line); border-radius: 10px; padding: 10px; min-height: 40px; max-height: 40vh; overflow: auto; }
.pgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(112px, 1fr)); gap: 8px; }
.pcell { border: 1px solid var(--line); border-radius: 10px; background: #fff; padding: 6px; cursor: pointer; text-align: center; font-size: 12px; color: var(--dim); }
.pcell:hover { border-color: var(--accent); }
.pcell.current { outline: 2px solid var(--accent); }
.pcell.done { background: #eef8f1; }
.pcell canvas { display: block; width: 100%; height: auto; }
.pcell b { display: block; color: var(--ink); font-weight: 600; margin-top: 4px; }
.piece-swatch { display: inline-block; width: 12px; height: 12px; border-radius: 3px; vertical-align: -2px; margin-right: 4px; border: 1px solid rgba(0,0,0,0.3); }
@media (max-width: 860px) {
  main { grid-template-columns: 1fr; }
  h1 { font-size: 22px; }
  #status { margin-left: 0; width: 100%; }
}