:root {
  --bg: #f6f8fa;
  --card-bg: #ffffff;
  --border: #d0d7de;
  --text: #1f2328;
  --text-muted: #656d76;
  --green-1: #dafbe1;
  --green-2: #26a641;
  --green-3: #2da44e;
  --green-4: #1a7f37;
  --empty: #eaeef2;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  padding: 2rem;
  min-height: 100vh;
}

h1 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.header {
  margin-bottom: 2rem;
}

.header p {
  color: var(--text-muted);
  font-size: 0.875rem;
}

#app {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.streak-card {
  --streak-color: var(--green-3);
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.5rem;
  flex: 1 1 0;
  min-width: 300px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.streak-title-row {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 0.25rem;
}

.streak-name {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--streak-color);
}

.streak-fire {
  font-size: 0.875rem;
  color: var(--streak-color);
  font-weight: 600;
}

.streak-desc {
  color: var(--text-muted);
  font-size: 0.8125rem;
  margin-bottom: 1rem;
  text-align: center;
}

.calendar-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.calendar-nav button {
  background: var(--empty);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  padding: 0.25rem 0.625rem;
  cursor: pointer;
  font-size: 0.8125rem;
  transition: background 0.15s;
}

.calendar-nav button:hover {
  background: var(--border);
}

.calendar-nav .month-label {
  font-size: 0.875rem;
  font-weight: 600;
  min-width: 140px;
  text-align: center;
}

.cal-container {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 36px);
  gap: 4px;
}

.calendar-grid .day-header {
  font-size: 0.6875rem;
  color: var(--text-muted);
  text-align: center;
  padding-bottom: 4px;
  font-weight: 500;
}

.calendar-grid .day-cell {
  border-radius: 4px;
  background: var(--empty);
  position: relative;
  cursor: default;
  width: 36px;
  height: 36px;
  transition: outline 0.1s;
}

.calendar-grid .day-cell.completed {
  background: var(--streak-color);
}

.calendar-grid .day-cell.today {
  outline: 2px solid var(--text-muted);
  outline-offset: -1px;
}

.calendar-grid .day-cell.outside {
  background: transparent;
}

.calendar-grid .day-cell .day-num {
  position: absolute;
  top: 3px;
  left: 5px;
  font-size: 0.625rem;
  color: var(--text-muted);
  pointer-events: none;
}

.calendar-grid .day-cell.completed .day-num {
  color: #fff;
}

.calendar-grid .day-cell .tooltip {
  display: none;
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  background: #ffffff;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.35rem 0.6rem;
  border-radius: 6px;
  font-size: 0.75rem;
  white-space: nowrap;
  z-index: 10;
  pointer-events: none;
}

.calendar-grid .day-cell:hover .tooltip {
  display: block;
}

.stats-row {
  display: flex;
  gap: 1.5rem;
  margin-top: 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.125rem;
}

.stat-value {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--streak-color);
}

.stat-label {
  font-size: 0.6875rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.legend {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  margin-top: 1rem;
  justify-content: center;
}

.legend span {
  font-size: 0.6875rem;
  color: var(--text-muted);
}

.legend-box {
  width: 12px;
  height: 12px;
  border-radius: 2px;
}