:root {
  color-scheme: dark;
  --ground: #0e1116;
  --panel: #161b22;
  --line: #2a313c;
  --ink: #e6e9ee;
  --soft: #a3adba;
  --accent: #f2b34a;
  --good: #7fd18b;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

header,
main {
  max-width: 1500px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  padding-top: 28px;
}

h1 {
  margin: 0;
  font-size: 2.2rem;
  letter-spacing: -0.02em;
}

h2 {
  margin: 0 0 10px;
  font-size: 1.05rem;
}

.lead {
  max-width: 62ch;
  margin: 6px 0 10px;
  font-size: 1.1rem;
  color: var(--soft);
}

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

.links a {
  margin-right: 18px;
}

a:focus-visible,
button:focus-visible,
.screen:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.machine {
  display: grid;
  grid-template-columns: minmax(0, auto) minmax(280px, 1fr);
  gap: 16px;
  margin-top: 18px;
}

.panel,
.try,
.notes {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px;
}

.screen {
  overflow-x: auto;
  background: #000;
  border-radius: 4px;
  padding: 6px;
}

.screen .text {
  white-space: pre;
  font: 14px/15px Consolas, "DejaVu Sans Mono", "Liberation Mono", monospace;
}

.screen canvas {
  display: none;
}

.status,
.hint {
  margin: 8px 0 0;
  font-size: 0.9rem;
  color: var(--soft);
}

.status.ready {
  color: var(--good);
}

.serial {
  height: 387px;
  margin: 0;
  overflow: auto;
  background: #000;
  border-radius: 4px;
  padding: 6px;
  font: 13px/1.35 Consolas, "DejaVu Sans Mono", "Liberation Mono", monospace;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  color: #c9d1d9;
}

.serial .report {
  color: var(--accent);
}

.try,
.notes {
  margin-top: 16px;
}

.try p,
.notes p {
  max-width: 78ch;
  margin: 0 0 10px;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 10px;
}

button {
  padding: 10px 12px;
  text-align: left;
  font: inherit;
  font-weight: 600;
  color: var(--ink);
  background: #1f2630;
  border: 1px solid var(--line);
  border-radius: 6px;
  cursor: pointer;
}

button span {
  display: block;
  margin-top: 2px;
  font-size: 0.86rem;
  font-weight: 400;
  color: var(--soft);
}

button:hover:not(:disabled) {
  border-color: var(--accent);
}

button:disabled {
  opacity: 0.5;
  cursor: default;
}

code {
  font-family: Consolas, "DejaVu Sans Mono", "Liberation Mono", monospace;
  font-size: 0.92em;
}

.credit {
  font-size: 0.9rem;
  color: var(--soft);
}

main {
  padding-bottom: 40px;
}

@media (max-width: 1100px) {
  .machine {
    grid-template-columns: minmax(0, 1fr);
  }

  .serial {
    height: 240px;
  }
}