:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #14141f;
  --bg-tertiary: #1e1e2e;
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --text-muted: #606070;
  --accent: #00d4ff;
  --accent-secondary: #00ff88;
  --danger: #ff4466;
  --warning: #ffaa44;
  --focus-ring: #00d4ff;
  --focus-glow: rgba(0, 212, 255, 0.4);
  --radius-md: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
}

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

html, body {
  width: 600px;
  height: 600px;
  overflow: hidden;
  background: #000;
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 18px;
  line-height: 1.4;
  -webkit-font-smoothing: antialiased;
}

#app { width: 100%; height: 100%; position: relative; }

.screen {
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  flex-direction: column;
  padding: 20px;
}

.screen.hidden { display: none; }

.focusable {
  transition: all 0.15s ease;
  border: 2px solid transparent;
  cursor: pointer;
  outline: none;
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-family: inherit;
  text-align: left;
}

.focusable:focus {
  border-color: var(--focus-ring);
  box-shadow: 0 0 20px var(--focus-glow);
  background: var(--bg-tertiary);
}

.hidden { display: none !important; }

.app-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  padding: 4px 4px 14px 4px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--bg-tertiary);
}

.header-left { min-width: 0; flex: 1; }

.header-right {
  text-align: right;
  flex-shrink: 0;
}

.date-line {
  font-size: 13px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 4px;
  font-weight: 600;
}

.screen-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.streak-summary {
  font-size: 28px;
  font-weight: 700;
  color: var(--warning);
  line-height: 1;
}

.streak-label {
  font-size: 11px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1.2px;
  margin-top: 4px;
}

/* Habit list */
.habit-list {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
  overflow-y: auto;
  padding: 2px;
}

.habit-list::-webkit-scrollbar { width: 0; }

.habit-item {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  border-radius: var(--radius-md);
  min-height: 68px;
  gap: 14px;
}

.habit-icon {
  font-size: 28px;
  width: 44px;
  text-align: center;
  flex-shrink: 0;
}

.habit-info {
  flex: 1;
  min-width: 0;
}

.habit-name {
  font-size: 18px;
  font-weight: 500;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin-bottom: 2px;
}

.habit-streak {
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
}

.habit-check {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--bg-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: var(--text-muted);
  flex-shrink: 0;
  font-weight: 700;
}

.habit-item.done .habit-check {
  background: var(--accent-secondary);
  color: #000;
}

.habit-item.done .habit-name {
  color: var(--text-secondary);
}

.habit-item.done .habit-streak {
  color: var(--accent-secondary);
}

/* Empty state */
.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  text-align: center;
  padding: 32px;
}

.empty-state .icon {
  font-size: 64px;
  margin-bottom: 18px;
  opacity: 0.7;
}

.empty-state .text {
  font-size: 17px;
  line-height: 1.5;
  max-width: 320px;
}

/* Bottom nav */
.bottom-nav {
  display: flex;
  gap: 12px;
  padding-top: 14px;
}

.nav-btn {
  flex: 1;
  border-radius: var(--radius-md);
  padding: 18px;
  font-size: 17px;
  font-weight: 600;
  min-height: 60px;
  text-align: center;
}

/* Detail screen */
.detail-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 14px;
}

.stat-card {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 14px 8px;
  text-align: center;
}

.stat-value {
  font-size: 32px;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 2px;
  line-height: 1;
}

.stat-label {
  font-size: 11px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1.2px;
  font-weight: 600;
}

.week-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 6px;
  margin-bottom: 14px;
}

.day-cell {
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  padding: 8px 4px;
  text-align: center;
  min-height: 60px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.day-cell.done {
  background: var(--accent-secondary);
  color: #000;
}

.day-cell.today {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.day-letter {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  opacity: 0.8;
}

.day-num {
  font-size: 18px;
  font-weight: 700;
  margin-top: 2px;
}

.detail-actions {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: auto;
}

.action-row {
  display: flex;
  gap: 8px;
}

.action-row .action-btn { flex: 1; }

.action-btn {
  border-radius: var(--radius-md);
  padding: 16px;
  font-size: 17px;
  font-weight: 600;
  min-height: 56px;
  text-align: center;
}

.action-btn.primary {
  background: var(--accent);
  color: #000;
  font-weight: 700;
  font-size: 18px;
  min-height: 64px;
}

.action-btn.primary.done {
  background: var(--accent-secondary);
}

.action-btn.primary:focus {
  background: var(--accent);
  filter: brightness(1.1);
}

.action-btn.danger {
  color: var(--danger);
}

/* Add screen */
.preset-list {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
  overflow-y: auto;
  padding: 2px;
}

.preset-list::-webkit-scrollbar { width: 0; }

.preset-item {
  border-radius: var(--radius-md);
  padding: 14px 16px;
  display: flex;
  align-items: center;
  gap: 14px;
  min-height: 60px;
}

.preset-item .icon {
  font-size: 26px;
  width: 36px;
  text-align: center;
  flex-shrink: 0;
}

.preset-item .label {
  font-size: 17px;
  font-weight: 500;
  flex: 1;
}

.preset-item.added {
  opacity: 0.5;
}

.preset-item.added .badge {
  font-size: 11px;
  color: var(--accent-secondary);
  text-transform: uppercase;
  font-weight: 700;
  letter-spacing: 1px;
}

/* Stats screen */
.stats-body {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 12px;
  align-content: stretch;
  margin-bottom: 14px;
}

.big-stat {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.big-value {
  font-size: 52px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 10px;
  letter-spacing: -1px;
}

.big-label {
  font-size: 13px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1.2px;
  text-align: center;
  font-weight: 600;
}