:root {
  --bg: #0b0b0b;
  --panel: #161514;
  --line: #2a2725;
  --text: #d9d4cc;
  --muted: #8d867c;
  --accent: #c8321e;
  --accent-hi: #e8513a;
  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
}

header {
  text-align: center;
  padding: 20px 16px 10px;
}

h1 {
  margin: 0;
  font-size: 34px;
  letter-spacing: 0.18em;
  color: var(--accent);
  font-weight: 900;
}
h1 span {
  color: var(--muted);
  font-size: 0.5em;
  letter-spacing: 0.1em;
  vertical-align: middle;
}

.tagline {
  margin: 4px 0 0;
  color: var(--muted);
}

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 16px;
}

/* The game keeps DOS proportions: 320x200 shown on a 4:3 monitor. */
#screen {
  position: relative;
  width: min(100%, calc((100vh - 170px) * 4 / 3));
  min-width: 280px;
  margin: 0 auto;
  aspect-ratio: 4 / 3;
  background: #000;
  border: 1px solid var(--line);
}

#canvas {
  display: block;
  width: 100%;
  height: 100%;
  outline: none;
}

#screen:fullscreen {
  width: 100vw;
  height: 100vh;
  max-width: none;
  border: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
#screen:fullscreen #canvas {
  width: min(100vw, 100vh * 4 / 3);
  height: min(100vh, 100vw * 3 / 4);
}

.overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: rgba(0, 0, 0, 0.82);
  color: var(--text);
  border: 0;
  font: inherit;
  text-align: center;
  padding: 16px;
}
button.overlay { cursor: pointer; }
button.overlay:disabled { cursor: progress; }
.overlay .big {
  font-size: clamp(20px, 4vw, 34px);
  font-weight: 800;
  color: var(--accent-hi);
  letter-spacing: 0.04em;
}
.overlay .small { color: var(--muted); }
.hidden { display: none !important; }

#endoom { background: #000; }
#endoom-canvas {
  width: 100%;
  max-height: calc(100% - 56px);
  object-fit: contain;
  image-rendering: pixelated;
}

#error pre {
  white-space: pre-wrap;
  color: var(--muted);
  max-width: 90%;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  align-items: center;
  margin: 14px 0 4px;
}

button, label.button {
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 7px 14px;
  font: inherit;
  cursor: pointer;
}
button:hover, label.button:hover { border-color: var(--accent); }
#endoom button, #error button {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

label.check {
  display: inline-flex;
  gap: 6px;
  align-items: center;
  color: var(--muted);
  cursor: pointer;
}

.wad-info {
  text-align: center;
  color: var(--muted);
  font-size: 13px;
  margin: 0 0 10px;
}

.help {
  border-top: 1px solid var(--line);
  margin-top: 18px;
  padding-top: 8px;
}
.help h2 {
  font-size: 15px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
}
.help dl {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 4px 24px;
  margin: 0;
}
.help dl > dt { font-weight: 700; }
.help dl > dd { margin: 0 0 6px; color: var(--muted); }
/* dt + dd pairs side by side */
.help dl { grid-template-columns: max-content 1fr max-content 1fr; }
@media (max-width: 700px) {
  .help dl { grid-template-columns: max-content 1fr; }
}
.note { color: var(--muted); font-size: 13px; }
code { color: var(--text); }

a { color: var(--accent-hi); }

footer {
  text-align: center;
  color: var(--muted);
  font-size: 12px;
  padding: 20px 16px 28px;
}

footer .credits {
  font-size: 14px;
  margin: 0 0 8px;
  color: var(--text);
}