:root {
  --bg: #14161a;
  --panel: #1d2026;
  --panel-2: #262a32;
  --text: #e7e9ee;
  --muted: #97a0b0;
  --accent: #dc3296;
  --border: #2e333d;
}

* { box-sizing: border-box; }

/* The HTML `hidden` attribute is just `display:none`, which any explicit
   `display` rule (e.g. .loading{display:flex}, main{display:grid}) would
   override. Make `hidden` win so toggling it from JS actually hides things. */
[hidden] { display: none !important; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

header {
  padding: 24px 28px 8px;
}
header h1 { margin: 0; font-size: 1.6rem; }
header .sub { color: var(--muted); margin: 6px 0 0; max-width: 70ch; }

/* loading overlay */
.loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 80px 20px;
  color: var(--muted);
}
.spinner {
  width: 42px; height: 42px;
  border: 4px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

main {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 24px;
  padding: 16px 28px 48px;
  align-items: start;
}
@media (max-width: 860px) {
  main { grid-template-columns: 1fr; }
}

/* controls panel */
.controls {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  position: sticky;
  top: 16px;
}

.dropzone {
  border: 2px dashed var(--border);
  border-radius: 10px;
  padding: 18px;
  text-align: center;
  transition: border-color 0.15s, background 0.15s;
}
.dropzone.over { border-color: var(--accent); background: var(--panel-2); }
.dropzone .hint { color: var(--muted); font-size: 0.85rem; margin: 6px 0 0; }
.link {
  background: none; border: none; color: var(--accent);
  cursor: pointer; font: inherit; text-decoration: underline; padding: 0;
}

fieldset {
  border: 1px solid var(--border);
  border-radius: 10px;
  margin: 18px 0 0;
  padding: 12px 14px 16px;
}
legend { color: var(--muted); padding: 0 6px; font-size: 0.85rem; }

.control { display: block; margin-top: 14px; }
.control:first-of-type { margin-top: 4px; }
.control-label {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 0.9rem;
  margin-bottom: 4px;
}
.control-label small { color: var(--muted); font-weight: normal; }
.control-label output {
  margin-left: auto;
  font-variant-numeric: tabular-nums;
  background: var(--panel-2);
  padding: 1px 8px;
  border-radius: 6px;
}
.control input[type="range"] { width: 100%; accent-color: var(--accent); }

.control.checkbox {
  display: flex; align-items: center; gap: 8px; margin-top: 16px;
}
.control.checkbox small { color: var(--muted); }

.render-toggles {
  margin-top: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px 14px;
  font-size: 0.88rem;
}
.render-toggles strong { width: 100%; color: var(--muted); font-weight: 600; }
.render-toggles label { display: inline-flex; align-items: center; gap: 5px; }

.island-report {
  margin-top: 18px;
  padding: 12px;
  background: var(--panel-2);
  border-radius: 8px;
  font-size: 0.9rem;
}
.island-report .warn { color: var(--accent); margin: 8px 0 0; }

/* results grid */
.results {
  display: grid;
  grid-template-columns: repeat(2, 1fr); /* 2x2 layout for larger previews */
  gap: 18px;
}
/* Drop to a single column when there isn't room for two side by side. */
@media (max-width: 700px) {
  .results { grid-template-columns: 1fr; }
}
.placeholder { color: var(--muted); grid-column: 1 / -1; }

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}
.card-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 12px;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--border);
}
.download {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  padding: 5px 12px;
  cursor: pointer;
  font-size: 0.82rem;
}
.download:hover { filter: brightness(1.1); }
.card canvas {
  display: block;
  width: 100%;
  height: auto;
  background:
    repeating-conic-gradient(#2a2e36 0% 25%, #20242b 0% 50%) 50% / 20px 20px;
}