:root {
  color-scheme: light dark;
  --bg: #101612;
  --panel: #17211b;
  --line: #2f4539;
  --text: #f2f6f3;
  --muted: #a7b6ad;
  --accent: #48c774;
  --danger: #ff6b6b;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.4 system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.panel {
  width: min(460px, 100%);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  padding: 24px;
}

h1 {
  margin: 0 0 20px;
  font-size: 28px;
  font-weight: 700;
}

label {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
}

.pair-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
}

input,
button {
  min-height: 44px;
  border-radius: 6px;
  border: 1px solid var(--line);
  font: inherit;
}

input {
  width: 100%;
  padding: 0 12px;
  background: #0f1712;
  color: var(--text);
}

button {
  padding: 0 14px;
  background: var(--accent);
  color: #06100a;
  border-color: transparent;
  font-weight: 700;
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

button.active {
  background: var(--danger);
  color: #190202;
}

.status,
.controls {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.status span {
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 8px 10px;
  color: var(--muted);
}

#message {
  min-height: 24px;
  margin: 18px 0 0;
  color: var(--muted);
}