:root {
  color-scheme: dark;
  --bg: #111827;
  --panel: #1f2937;
  --card: #374151;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --accent: #22c55e;
  --accent-2: #0ea5e9;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: radial-gradient(circle at top, #1e293b, var(--bg));
  color: var(--text);
}

header {
  padding: 1.5rem;
  border-bottom: 1px solid #334155;
}

header h1 {
  margin: 0;
}

header p {
  margin: 0.4rem 0 0;
  color: var(--muted);
}

main {
  display: grid;
  grid-template-columns: repeat(3, minmax(260px, 1fr));
  gap: 1rem;
  padding: 1rem;
}

.panel {
  background: #0f172a80;
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 1rem;
  min-height: 70vh;
}

.stack {
  display: grid;
  gap: 0.6rem;
}

.card,
.block {
  background: var(--card);
  border-radius: 10px;
  padding: 0.7rem;
  border: 1px solid #4b5563;
}

.block {
  cursor: pointer;
  border-left: 5px solid var(--accent-2);
}

.workspace {
  min-height: 300px;
  border: 1px dashed #64748b;
  border-radius: 12px;
  padding: 0.7rem;
  display: grid;
  gap: 0.5rem;
  margin-top: 0.7rem;
}

.workspace-block {
  background: #1e293b;
  border-left-color: var(--accent);
}

.workspace-block input {
  width: 100%;
  margin-top: 0.45rem;
  background: #111827;
  color: var(--text);
  border: 1px solid #475569;
  border-radius: 8px;
  padding: 0.35rem 0.5rem;
}

.green-flag {
  background: linear-gradient(120deg, #14532d, #166534);
  border-color: #22c55e;
}

label {
  display: grid;
  gap: 0.3rem;
  margin-bottom: 0.45rem;
  font-size: 0.9rem;
}

input {
  background: #111827;
  color: var(--text);
  border: 1px solid #475569;
  border-radius: 8px;
  padding: 0.45rem;
}

button {
  background: #334155;
  color: var(--text);
  border: none;
  border-radius: 8px;
  padding: 0.5rem 0.7rem;
  cursor: pointer;
}

button:hover {
  filter: brightness(1.15);
}

.controls {
  display: flex;
  gap: 0.6rem;
  margin-top: 0.7rem;
}

.run {
  background: #15803d;
}

.output,
.code-view {
  background: #020617;
  border: 1px solid #334155;
  border-radius: 8px;
  min-height: 150px;
  padding: 0.7rem;
  white-space: pre-wrap;
}

.tabs {
  display: flex;
  gap: 0.35rem;
  margin-bottom: 0.6rem;
}

.tab.active {
  background: #0369a1;
}

.note {
  margin-top: 0.7rem;
  color: var(--muted);
}

@media (max-width: 1100px) {
  main {
    grid-template-columns: 1fr;
  }

  .panel {
    min-height: auto;
  }
}