:root {
  --bg: #14161b;
  --panel: #1c1f26;
  --panel2: #232732;
  --border: #2e333d;
  --text: #e6e8eb;
  --muted: #9aa4b0;
  --accent: #5b8def;
  --accent2: #3ec0a8;
  --danger: #d6597c;
  --radius: 8px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

header {
  padding: 16px 24px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: baseline;
  gap: 12px;
}
header h1 { font-size: 20px; margin: 0; }
header .tag { color: var(--muted); font-size: 13px; }

main { padding: 20px 24px; max-width: 1400px; margin: 0 auto; }

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 20px;
}
.card h2 { font-size: 15px; margin: 0 0 12px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.04em; }

.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.row + .row { margin-top: 10px; }

label { font-size: 13px; color: var(--muted); }
input[type="text"], input[type="number"], select {
  background: var(--panel2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 13px;
}
input[type="number"] { width: 80px; }
input.dim-input {
  width: 100px;
  font-size: 15px;
  font-weight: 600;
  padding: 8px 10px;
}

button {
  background: var(--accent);
  color: #0a0a0a;
  border: none;
  border-radius: 6px;
  padding: 8px 16px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}
button.secondary { background: var(--panel2); color: var(--text); border: 1px solid var(--border); }
button.danger { background: var(--danger); color: #fff; }
button:disabled { opacity: 0.5; cursor: not-allowed; }
button:hover:not(:disabled) { filter: brightness(1.1); }

#dropzone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 28px;
  text-align: center;
  color: var(--muted);
  cursor: pointer;
}
#dropzone.drag { border-color: var(--accent); color: var(--text); }

table { width: 100%; border-collapse: collapse; font-size: 13px; }
th, td { padding: 6px 8px; border-bottom: 1px solid var(--border); text-align: left; }
th { color: var(--muted); font-weight: 600; }
th.col-dim { font-size: 13.5px; color: var(--text); min-width: 100px; }
td input { width: 100%; }
.swatch { width: 16px; height: 16px; border-radius: 3px; display: inline-block; vertical-align: middle; }

.tabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 12px; }
.tabs button { background: var(--panel2); color: var(--text); border: 1px solid var(--border); }

.viewToggle { display: flex; gap: 6px; margin-bottom: 12px; }
.viewToggle button { background: var(--panel2); color: var(--text); border: 1px solid var(--border); }

.tabs button.active, .viewToggle button.active { background: var(--accent); color: #0a0a0a; }

.box-layout { display: flex; gap: 16px; align-items: stretch; }
.box-view { flex: 1; min-width: 0; }
#canvas2d { width: 100%; height: 480px; display: block; border-radius: var(--radius); background: var(--panel2); }
#view3d { width: 100%; height: 480px; border-radius: var(--radius); overflow: hidden; background: #1c1f26; }
.box-stats { font-size: 12px; color: var(--muted); margin-top: 8px; }

.steps-panel { width: 320px; flex-shrink: 0; background: var(--panel2); border-radius: var(--radius); padding: 10px; max-height: 480px; overflow-y: auto; }
.steps-panel .step { display: flex; gap: 8px; align-items: flex-start; padding: 6px 4px; border-bottom: 1px solid var(--border); font-size: 12.5px; }
.steps-panel .step .n { background: var(--accent); color: #0a0a0a; border-radius: 50%; width: 20px; height: 20px; flex: none; display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 11px; }
.steps-panel .step.active { background: rgba(91, 141, 239, 0.18); border-radius: 6px; }

.unplaced { background: rgba(214, 89, 124, 0.12); border: 1px solid var(--danger); border-radius: var(--radius); padding: 10px; margin-top: 12px; font-size: 13px; }

.hidden { display: none !important; }
.muted { color: var(--muted); font-size: 12px; }

.small-btn { padding: 4px 8px; font-size: 11px; }
.small-btn + .small-btn { margin-left: 4px; }

/* ---------- Splash screen ---------- */
#splashCard { text-align: center; padding: 40px 24px; }
#splashCard h2 { font-size: 22px; text-transform: none; letter-spacing: normal; color: var(--text); }
.splash-intro { color: var(--muted); font-size: 14px; margin: 0 0 28px; line-height: 1.6; }
.splash-options { display: flex; gap: 20px; justify-content: center; flex-wrap: wrap; }
.splash-option {
  background: var(--panel2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  width: 260px;
  padding: 28px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  text-align: center;
  font-weight: 400;
  transition: border-color 0.15s, transform 0.15s;
}
.splash-option:hover { border-color: var(--accent); transform: translateY(-2px); }
.splash-icon { font-size: 34px; }
.splash-title { font-size: 16px; font-weight: 700; color: var(--text); }
.splash-desc { font-size: 12.5px; color: var(--muted); line-height: 1.5; }

.link-btn {
  background: none;
  border: none;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  padding: 0;
  margin-bottom: 14px;
  cursor: pointer;
}
.link-btn:hover { text-decoration: underline; }

.table-wrap { overflow-x: auto; }

/* ---------- Mobil / planshet uchun responsive ---------- */
@media (max-width: 900px) {
  .box-layout { flex-direction: column; }
  .steps-panel { width: 100%; max-height: 280px; }
  #canvas2d, #view3d { height: 60vh; min-height: 280px; }
}

@media (max-width: 640px) {
  header { flex-wrap: wrap; padding: 12px 16px; }
  main { padding: 12px; }
  .card { padding: 12px; }
  .row { gap: 8px; }
  .row label { display: flex; flex-direction: column; gap: 4px; font-size: 12px; }
  input[type="number"] { width: 100%; }
  input.dim-input { width: 100%; }
  button { padding: 10px 14px; }
  #startBtn { width: 100%; }
  .splash-options { flex-direction: column; align-items: stretch; }
  .splash-option { width: 100%; }
  .viewToggle { flex-wrap: wrap; }
  .viewToggle #pdfBtn { margin-left: 0 !important; width: 100%; }
  #canvas2d, #view3d { height: 50vh; }
}