/* Duna-inspired: warm pastel washes, light typography, wide spacing, no motion. */
:root {
  --ink: #45392f; --muted: #93857a; --line: #eadfd2;
  --panel: rgba(255, 255, 255, .72); --card: rgba(255, 255, 255, .55);
  --accent: #ef6c35; --accent-ink: #fff;
  --ok: #1a7f4b; --err: #c0392b;
  /* soft hand-painted wash: layered color blobs on warm cream */
  --canvas:
    radial-gradient(55% 40% at 12% 8%, #f7dfc8 0%, transparent 70%),
    radial-gradient(45% 45% at 92% 18%, #e9dfee 0%, transparent 70%),
    radial-gradient(60% 50% at 80% 95%, #f2cdbd 0%, transparent 72%),
    radial-gradient(50% 40% at 15% 90%, #e3e7d6 0%, transparent 70%),
    #faf3ea;
  /* painted dusk landscape behind the 3D model */
  --stage:
    radial-gradient(65% 45% at 18% 104%, #e8c9b0 0%, transparent 70%),
    radial-gradient(75% 42% at 86% 106%, #d9b8a6 0%, transparent 75%),
    radial-gradient(55% 60% at 70% 8%, rgba(255, 236, 210, .8) 0%, transparent 70%),
    linear-gradient(#f2dbc4, #f9efe2 55%, #f4e2d0);
  --stage-hint: #8a7365;
}
@media (prefers-color-scheme: dark) {
  :root {
    --ink: #ece4dc; --muted: #a2968c; --line: #4a4038;
    --panel: rgba(38, 32, 29, .78); --card: rgba(48, 41, 37, .6);
    --canvas:
      radial-gradient(55% 40% at 12% 8%, #3d2f28 0%, transparent 70%),
      radial-gradient(45% 45% at 92% 18%, #342d3b 0%, transparent 70%),
      radial-gradient(60% 50% at 80% 95%, #42302b 0%, transparent 72%),
      #241d1a;
    --stage:
      radial-gradient(65% 45% at 18% 104%, #4a3327 0%, transparent 70%),
      radial-gradient(75% 42% at 86% 106%, #3c2c24 0%, transparent 75%),
      radial-gradient(55% 60% at 70% 8%, rgba(120, 84, 60, .35) 0%, transparent 70%),
      linear-gradient(#332723, #2a211d 55%, #302523);
    --stage-hint: #b3a294;
  }
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  font: 15px/1.65 Inter, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--ink); background: var(--canvas); background-attachment: fixed;
}

main {
  display: grid; grid-template-columns: 400px 1fr;
  gap: 26px; padding: 26px; height: 100vh;
}
@media (max-width: 860px) { main { grid-template-columns: 1fr; height: auto; } }

/* panels float as soft cards on the painted canvas */
#panel {
  padding: 38px 34px; overflow-y: auto;
  background: var(--panel); border: 1px solid var(--line); border-radius: 22px;
  box-shadow: 0 18px 50px -30px rgba(96, 66, 44, .35);
}
h1 { margin: 0 0 10px; font-size: 30px; font-weight: 350; letter-spacing: -.01em; }
.lead { margin: 0 0 30px; color: var(--muted); font-weight: 300; max-width: 30em; }

form { display: flex; flex-direction: column; gap: 18px; }
label { display: flex; flex-direction: column; gap: 6px; font-weight: 500; font-size: 13px; }
.hint { font-weight: 300; color: var(--muted); }
small { font-weight: 300; color: var(--muted); font-size: 12px; }
.row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }

input, select {
  font: inherit; font-weight: 400; padding: 10px 13px;
  border: 1px solid var(--line); border-radius: 12px;
  background: var(--card); color: var(--ink);
}
input[type="range"] { padding: 0; accent-color: var(--accent); background: none; border: none; }
input:focus, select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }

button {
  font: inherit; font-weight: 600; cursor: pointer; padding: 12px 18px;
  border: 1px solid var(--line); border-radius: 14px;
  background: var(--card); color: var(--ink);
}
#go { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); margin-top: 8px; }
#go:disabled { opacity: .6; cursor: progress; }

#status { margin: 18px 0 6px; min-height: 1.2em; font-weight: 500; }
#status.busy { color: var(--muted); }
#status.ok { color: var(--ok); }
#status.err { color: var(--err); }
#meta { margin: 0; color: var(--muted); font-size: 13px; font-weight: 300; }

#downloads { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
#downloads small { flex-basis: 100%; }

#guide { margin-top: 26px; border-top: 1px solid var(--line); padding-top: 18px; }
#guide summary {
  cursor: pointer; font-weight: 500; padding: 10px 16px; border: 1px solid var(--line);
  border-radius: 14px; background: var(--card); list-style: none; width: fit-content;
}
#guide summary::-webkit-details-marker { display: none; }
#guide summary::before { content: "▸ "; color: var(--accent); }
#guide[open] summary::before { content: "▾ "; }
#guide h3 { font-size: 14px; font-weight: 500; margin: 18px 0 6px; }
#guide ol { margin: 0 0 8px; padding-left: 20px; }
#guide li { margin-bottom: 5px; }
#guide p { margin: 8px 0; color: var(--muted); font-weight: 300; }

#stage {
  position: relative; background: var(--stage);
  border: 1px solid var(--line); border-radius: 22px; overflow: hidden;
  box-shadow: 0 18px 50px -30px rgba(96, 66, 44, .35);
}
@media (max-width: 860px) { #stage { height: 60vh; } }
#viewer { position: absolute; inset: 0; }
#zoomctl { position: absolute; right: 16px; bottom: 16px; display: flex; flex-direction: column; gap: 8px; }
#zoomctl button {
  width: 40px; height: 40px; padding: 0; font-size: 20px; font-weight: 400;
  line-height: 1; border-radius: 50%;
}
.viewhint {
  position: absolute; left: 0; right: 0; bottom: 12px; margin: 0; text-align: center;
  color: var(--stage-hint); font-size: 12px; font-weight: 300; pointer-events: none;
}