:root {
  --bg: #0f172a;
  --panel: #111827;
  --line: #243244;
  --cell: #0e1a2b;
  --cell-active: #08d1b0;
  --text: #e5e7eb;
  --muted: #9aa7b8;
  --accent: #006f54;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  height: 100%;
  font-family: sans-serif;
}

body {
  background-color: var(--bg);
  color: var(--text);
}

#app {
  max-width: 960px;
  margin: 0 auto;
  padding: 12px;
}

/* Header */
.app-header {
  margin-bottom: 12px;
}

.title {
  font-size: 20px;
}

/* Controls */
#controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 10px 0 10px 0;
}

.btn,
.wave-select,
.tempo-input {
  border: 1px solid var(--line);
  border-radius: 6px;
  background-color: var(--panel);
  color: var(--text);
  padding: 8px 10px;
}

.btn {
  cursor: pointer;
}

.btn:hover {
  background-color: #354b7a;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.divider {
  opacity: 0.6;
  color: var(--muted);
}

/* Grid Container */
.grid {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px;
  background-color: #0b1422;
  min-width: fit-content;
  max-width: fit-content;
}

.grid-layout {
  display: grid;
  grid-template-columns: 60px 1fr;
  gap: 6px;
}

/* Grid Left Side */
.labels-left-side {
  display: flex;
  flex-direction: column;
}

.ruler-spacer {
  height: 22px;
  margin: 0;
}

.row-labels {
  display: grid;
  /* number of rows is dynamic in JS */
  /* grid-template-rows: repeat(8, 32px); */
  gap: 4px;
}

.row-label {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  font-size: 12px;
  border: 1px solid var(--muted);
  border-radius: 4px;
}

/* Grid Right Side */
/* Top Ruler Numbers / Beat Numbers */
.ruler {
  display: grid;
  /* number of columns is dynamic in JS */
  /* grid-template-columns: repeat(16, 1fr); */
  gap: 4px;
  margin: 0;
}

.ruler-cell {
  height: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  border: 1px solid var(--muted);
  border-radius: 4px;
}

.ruler-cell.beat {
  background-color: #0552b7;
}

.ruler-cell.playing-col {
  background-color: #faffc8;
}

/* Bottom Grid Inner */
.grid-inner {
  display: grid;
  /* TODO: make the number of columns dynamic */
  grid-template-columns: repeat(16, 1fr);
  grid-auto-rows: 32px;
  gap: 4px;
}

.cell {
  border: 1px solid var(--line);
  border-radius: 4px;
  background-color: var(--cell);
  cursor: pointer;
  /* TEMPORARY */
  color: var(--text);
}

.cell:hover {
  background-color: #1c3455;
}

.cell.active {
  background-color: var(--cell-active);
  border-color: var(--accent);
}

.cell.playing-col {
  outline: 1px solid #f6ffa5;
}