/* =========================================
   STREAKS — Habit Tracker
   Design: Warm editorial dark/light
   ========================================= */

/* --- Google Fonts (preloaded in HTML) --- */

/* --- CSS Variables --- */
:root {
  --font-display: 'DM Serif Display', Georgia, serif;
  --font-body: 'DM Sans', system-ui, sans-serif;

  /* Dark theme (default) */
  --bg: #0F0F13;
  --bg-2: #17171F;
  --bg-3: #1E1E28;
  --bg-4: #252530;
  --border: rgba(255,255,255,0.07);
  --border-strong: rgba(255,255,255,0.13);
  --text: #F0EDE8;
  --text-2: #A9A59E;
  --text-3: #6B6760;
  --accent: #F59E0B;
  --accent-dim: rgba(245,158,11,0.15);
  --accent-glow: rgba(245,158,11,0.25);
  --success: #10B981;
  --success-dim: rgba(16,185,129,0.15);
  --danger: #EF4444;
  --danger-dim: rgba(239,68,68,0.15);
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.6);
  --radius: 14px;
  --radius-sm: 8px;
  --radius-xs: 5px;
  --topbar-h: 64px;
  --sidebar-w: 280px;
  --transition: 0.2s cubic-bezier(0.4,0,0.2,1);

  /* Heatmap colors */
  --heat-0: #1E1E28;
  --heat-1: rgba(245,158,11,0.2);
  --heat-2: rgba(245,158,11,0.45);
  --heat-3: rgba(245,158,11,0.7);
  --heat-4: #F59E0B;
}

[data-theme="light"] {
  --bg: #F7F5F0;
  --bg-2: #FFFFFF;
  --bg-3: #F0EDE8;
  --bg-4: #E8E4DD;
  --border: rgba(0,0,0,0.07);
  --border-strong: rgba(0,0,0,0.13);
  --text: #1A1814;
  --text-2: #5C5750;
  --text-3: #9C9890;
  --shadow: 0 4px 24px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.14);
  --heat-0: #E8E4DD;
  --heat-1: rgba(245,158,11,0.2);
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  transition: background var(--transition), color var(--transition);
  overflow-x: hidden;
}

::selection { background: var(--accent-dim); color: var(--accent); }

/* --- Scrollbar --- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--bg-4); border-radius: 99px; }

/* --- Confetti Canvas --- */
#confetti-canvas {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  z-index: 9999;
}

/* =========================================
   TOPBAR
   ========================================= */
.topbar {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--topbar-h);
  background: var(--bg-2);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  backdrop-filter: blur(12px);
}

.topbar-left, .topbar-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-icon {
  font-size: 1.3rem;
  color: var(--accent);
  animation: pulse-icon 3s ease-in-out infinite;
}

@keyframes pulse-icon {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

.logo-text {
  font-family: var(--font-display);
  font-size: 1.35rem;
  letter-spacing: -0.01em;
  color: var(--text);
}

.date-display {
  font-size: 0.8rem;
  color: var(--text-3);
  font-weight: 400;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* --- Buttons --- */
.btn-primary {
  background: var(--accent);
  color: #1A1814;
  border: none;
  border-radius: var(--radius-sm);
  padding: 8px 16px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
  white-space: nowrap;
}
.btn-primary:hover {
  opacity: 0.9;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px var(--accent-glow);
}
.btn-primary:active { transform: scale(0.97); }

.btn-ghost {
  background: transparent;
  color: var(--text-2);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 8px 16px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.btn-ghost:hover { background: var(--bg-3); color: var(--text); }

.btn-icon {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  width: 36px; height: 36px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  color: var(--text-2);
  font-size: 1rem;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.btn-icon:hover { background: var(--bg-3); color: var(--text); border-color: var(--border-strong); }

.btn-icon.btn-danger:hover { background: var(--danger-dim); color: var(--danger); border-color: var(--danger); }

.btn-danger-solid {
  background: var(--danger);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  padding: 8px 16px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: opacity var(--transition);
}
.btn-danger-solid:hover { opacity: 0.85; }

.btn-xs {
  background: rgba(255,255,255,0.12);
  color: var(--text);
  border: none;
  border-radius: var(--radius-xs);
  padding: 4px 10px;
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}

/* Theme toggle icons */
.btn-icon .icon-sun { display: none; }
.btn-icon .icon-moon { display: block; }
[data-theme="light"] .btn-icon .icon-sun { display: block; }
[data-theme="light"] .btn-icon .icon-moon { display: none; }

/* =========================================
   MODAL
   ========================================= */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.65);
  backdrop-filter: blur(4px);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: all;
}

.modal {
  background: var(--bg-2);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
  width: 100%;
  max-width: 480px;
  box-shadow: var(--shadow-lg);
  transform: translateY(16px) scale(0.97);
  transition: transform var(--transition);
}

.modal-overlay.open .modal {
  transform: translateY(0) scale(1);
}

.modal-sm { max-width: 360px; }

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px 16px;
  border-bottom: 1px solid var(--border);
}

.modal-header h2 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 400;
}

.modal-body { padding: 20px 24px; }

.modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  padding: 16px 24px 20px;
  border-top: 1px solid var(--border);
}

/* --- Form elements --- */
.form-group { margin-bottom: 16px; }
.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 6px;
}

.form-group input,
.form-group select {
  width: 100%;
  background: var(--bg-3);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--text);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
}

.form-group input::placeholder { color: var(--text-3); }

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

/* Color picker */
.color-picker {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.color-swatch {
  width: 28px; height: 28px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform var(--transition), border-color var(--transition);
}
.color-swatch:hover { transform: scale(1.15); }
.color-swatch.selected {
  border-color: var(--text);
  transform: scale(1.2);
  box-shadow: 0 0 0 2px var(--bg-3);
}

/* =========================================
   MAIN LAYOUT
   ========================================= */
.main-layout {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  min-height: calc(100vh - var(--topbar-h));
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px 24px 40px;
  gap: 24px;
}

/* =========================================
   SIDEBAR
   ========================================= */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.sidebar-card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.stat-big {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 16px;
}

.stat-num {
  font-family: var(--font-display);
  font-size: 3rem;
  line-height: 1;
  color: var(--accent);
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
}

.stat-row {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 8px;
  margin-bottom: 20px;
}

.stat-mini {
  background: var(--bg-3);
  border-radius: var(--radius-sm);
  padding: 10px 8px;
  text-align: center;
}

.stat-num-sm {
  display: block;
  font-family: var(--font-display);
  font-size: 1.2rem;
  color: var(--text);
  line-height: 1.2;
}

.stat-label-sm {
  display: block;
  font-size: 0.7rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  margin-top: 2px;
}

/* Weekly Chart */
.chart-title {
  font-size: 0.75rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
  margin-bottom: 10px;
}

.chart-bars {
  display: flex;
  align-items: flex-end;
  gap: 6px;
  height: 60px;
}

.chart-bar-wrap {
  flex: 1;
  height: 100%;
  display: flex;
  align-items: flex-end;
}

.chart-bar {
  width: 100%;
  background: var(--accent);
  border-radius: 3px 3px 0 0;
  min-height: 3px;
  transition: height 0.6s cubic-bezier(0.34,1.56,0.64,1);
  opacity: 0.85;
  position: relative;
}

.chart-bar.today { opacity: 1; box-shadow: 0 0 8px var(--accent-glow); }
.chart-bar.empty { background: var(--bg-4); opacity: 1; }

.chart-labels {
  display: flex;
  gap: 6px;
  margin-top: 4px;
}

.chart-label {
  flex: 1;
  text-align: center;
  font-size: 0.65rem;
  color: var(--text-3);
  font-weight: 500;
}

.chart-label.today { color: var(--accent); font-weight: 700; }

/* Insights */
.panel-title {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.insight-item {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  animation: slide-in 0.3s ease;
}

.insight-item:last-child { border-bottom: none; }

.insight-icon { font-size: 1rem; flex-shrink: 0; margin-top: 1px; }

.insight-text {
  font-size: 0.82rem;
  color: var(--text-2);
  line-height: 1.4;
}

@keyframes slide-in {
  from { opacity: 0; transform: translateX(-8px); }
  to { opacity: 1; transform: translateX(0); }
}

/* Reminder Banner */
.reminder-banner {
  background: linear-gradient(135deg, var(--accent-dim), transparent);
  border: 1px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  display: flex;
  align-items: center;
  gap: 8px;
  animation: slide-down 0.4s ease;
}

.reminder-banner.hidden { display: none; }

@keyframes slide-down {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

.reminder-icon { font-size: 1.1rem; flex-shrink: 0; }

.reminder-banner span:nth-child(2) {
  flex: 1;
  font-size: 0.82rem;
  color: var(--text);
  line-height: 1.4;
}

/* =========================================
   CONTENT AREA — TABS
   ========================================= */
.content-area {
  min-width: 0;
}

.tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 20px;
  background: var(--bg-2);
  border-radius: var(--radius-sm);
  padding: 4px;
  width: fit-content;
  border: 1px solid var(--border);
}

.tab {
  background: transparent;
  border: none;
  border-radius: 6px;
  padding: 7px 18px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-3);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

.tab:hover { color: var(--text-2); }

.tab.active {
  background: var(--accent);
  color: #1A1814;
  font-weight: 700;
}

.tab-panel { display: none; }
.tab-panel.active { display: block; animation: fade-in 0.3s ease; }

@keyframes fade-in {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* =========================================
   EMPTY STATE
   ========================================= */
.empty-state {
  text-align: center;
  padding: 60px 24px;
  color: var(--text-3);
}

.empty-state.hidden { display: none; }

.empty-icon {
  font-size: 3rem;
  color: var(--accent);
  opacity: 0.4;
  margin-bottom: 16px;
  animation: pulse-icon 2s ease-in-out infinite;
}

.empty-state h3 {
  font-family: var(--font-display);
  font-size: 1.4rem;
  color: var(--text-2);
  font-weight: 400;
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 0.9rem;
  margin-bottom: 24px;
}

/* =========================================
   HABITS GRID
   ========================================= */
.habits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.habit-card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 18px 14px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
  animation: card-in 0.35s cubic-bezier(0.34,1.56,0.64,1);
}

@keyframes card-in {
  from { opacity: 0; transform: scale(0.92) translateY(10px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

.habit-card:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.habit-card.done {
  border-color: var(--success);
  box-shadow: 0 0 0 1px var(--success-dim), var(--shadow);
}

/* Color accent bar */
.habit-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--habit-color, var(--accent));
}

.habit-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 12px;
}

.habit-name {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 400;
  line-height: 1.3;
  flex: 1;
  margin-right: 8px;
}

.habit-actions {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}

.habit-actions button {
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 4px 5px;
  border-radius: var(--radius-xs);
  color: var(--text-3);
  font-size: 0.85rem;
  transition: background var(--transition), color var(--transition);
  line-height: 1;
}

.habit-actions button:hover { background: var(--bg-3); color: var(--text); }
.habit-actions .del-btn:hover { background: var(--danger-dim); color: var(--danger); }

.habit-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
}

.streak-badge {
  display: flex;
  align-items: center;
  gap: 4px;
  background: var(--bg-3);
  border-radius: 99px;
  padding: 3px 9px;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent);
}

.streak-badge.hot {
  background: var(--accent-dim);
  animation: streak-pulse 1.5s ease-in-out infinite;
}

@keyframes streak-pulse {
  0%, 100% { box-shadow: 0 0 0 0 var(--accent-glow); }
  50% { box-shadow: 0 0 0 4px var(--accent-glow); }
}

.freq-tag {
  font-size: 0.7rem;
  color: var(--text-3);
  background: var(--bg-4);
  border-radius: 99px;
  padding: 2px 8px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

/* Progress Bar */
.habit-progress {
  margin-bottom: 14px;
}

.progress-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  color: var(--text-3);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 5px;
}

.progress-bar {
  height: 5px;
  background: var(--bg-4);
  border-radius: 99px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--habit-color, var(--accent));
  border-radius: 99px;
  transition: width 0.6s cubic-bezier(0.34,1.56,0.64,1);
  min-width: 0;
}

/* Toggle Button */
.toggle-btn {
  width: 100%;
  border: 2px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 10px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all var(--transition);
  background: transparent;
  color: var(--text-2);
  position: relative;
  overflow: hidden;
}

.toggle-btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--habit-color, var(--accent));
  opacity: 0;
  transition: opacity var(--transition);
}

.toggle-btn:hover {
  border-color: var(--habit-color, var(--accent));
  color: var(--text);
}

.toggle-btn.done {
  border-color: var(--success);
  background: var(--success-dim);
  color: var(--success);
}

.toggle-btn .checkmark {
  display: inline-block;
  transition: transform 0.3s cubic-bezier(0.34,1.56,0.64,1);
}

.toggle-btn.done .checkmark {
  transform: scale(1.3) rotate(-10deg);
  animation: check-bounce 0.4s cubic-bezier(0.34,1.56,0.64,1);
}

@keyframes check-bounce {
  0% { transform: scale(0.5) rotate(-20deg); }
  70% { transform: scale(1.4) rotate(-5deg); }
  100% { transform: scale(1.3) rotate(-10deg); }
}

/* Mini Calendar (last 7 dots in card) */
.mini-dots {
  display: flex;
  gap: 4px;
  margin-top: 10px;
  justify-content: flex-end;
}

.mini-dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--bg-4);
}

.mini-dot.done { background: var(--habit-color, var(--accent)); opacity: 0.8; }
.mini-dot.today { width: 9px; height: 9px; }

/* Missed recovery message */
.recovery-msg {
  margin-top: 8px;
  padding: 7px 10px;
  background: var(--bg-3);
  border-radius: var(--radius-xs);
  font-size: 0.78rem;
  color: var(--text-2);
  border-left: 2px solid var(--accent);
  animation: slide-in 0.3s ease;
}

/* =========================================
   CALENDAR VIEW
   ========================================= */
.select-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}

.select-row label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.select-row select {
  background: var(--bg-2);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 7px 12px;
  font-family: var(--font-body);
  font-size: 0.875rem;
  color: var(--text);
  outline: none;
  appearance: none;
  cursor: pointer;
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 8px;
}

.cal-header {
  text-align: center;
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 4px;
}

.cal-cell {
  aspect-ratio: 1;
  border-radius: var(--radius-sm);
  background: var(--bg-3);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  cursor: pointer;
  transition: transform var(--transition);
}

.cal-cell:hover { transform: scale(1.05); }

.cal-date {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-3);
  line-height: 1;
  margin-bottom: 3px;
}

.cal-icon {
  font-size: 1rem;
}

.cal-cell.done {
  background: var(--success-dim);
  border: 1px solid rgba(16,185,129,0.3);
}

.cal-cell.missed {
  background: var(--danger-dim);
  border: 1px solid rgba(239,68,68,0.15);
}

.cal-cell.future {
  opacity: 0.3;
  cursor: default;
}

.cal-cell.today {
  border: 2px solid var(--accent);
}

/* =========================================
   HEATMAP
   ========================================= */
.heatmap-container {
  overflow-x: auto;
  padding-bottom: 8px;
}

.heatmap-grid {
  display: grid;
  grid-template-rows: 16px repeat(7, 14px);
  gap: 3px;
  width: fit-content;
}

.heatmap-week {
  display: contents;
}

.heatmap-month-row {
  display: flex;
  gap: 3px;
}

.heatmap-month-label {
  font-size: 0.65rem;
  color: var(--text-3);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.heatmap-day-labels {
  display: flex;
  flex-direction: column;
  gap: 3px;
  margin-right: 6px;
  margin-top: 19px;
}

.heatmap-day-label {
  font-size: 0.62rem;
  color: var(--text-3);
  font-weight: 600;
  text-transform: uppercase;
  height: 14px;
  line-height: 14px;
}

.heatmap-wrapper {
  display: flex;
  gap: 0;
}

.heatmap-weeks {
  display: flex;
  gap: 3px;
}

.heatmap-col {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.heatmap-cell {
  width: 14px; height: 14px;
  border-radius: 2px;
  background: var(--heat-0);
  transition: transform 0.15s ease, background 0.15s ease;
  cursor: pointer;
}

.heatmap-cell:hover { transform: scale(1.4); z-index: 1; }

.heatmap-cell[data-level="1"] { background: var(--heat-1); }
.heatmap-cell[data-level="2"] { background: var(--heat-2); }
.heatmap-cell[data-level="3"] { background: var(--heat-3); }
.heatmap-cell[data-level="4"] { background: var(--heat-4); }

/* Heatmap custom color */
.heatmap-cell.colored[data-level="1"] { opacity: 0.2; }
.heatmap-cell.colored[data-level="2"] { opacity: 0.45; }
.heatmap-cell.colored[data-level="3"] { opacity: 0.7; }
.heatmap-cell.colored[data-level="4"] { opacity: 1; }

.heatmap-month-headers {
  display: flex;
  gap: 3px;
  margin-left: 0;
  margin-bottom: 3px;
  height: 16px;
}

.month-header-item {
  font-size: 0.65rem;
  color: var(--text-3);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

/* Legend */
.heatmap-legend {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-top: 12px;
  justify-content: flex-end;
}

.legend-label {
  font-size: 0.7rem;
  color: var(--text-3);
  font-weight: 600;
}

.legend-cells {
  display: flex;
  gap: 3px;
}

.legend-cell {
  width: 12px; height: 12px;
  border-radius: 2px;
  background: var(--heat-0);
}

.legend-cell[data-level="1"] { background: var(--heat-1); }
.legend-cell[data-level="2"] { background: var(--heat-2); }
.legend-cell[data-level="3"] { background: var(--heat-3); }
.legend-cell[data-level="4"] { background: var(--heat-4); }

/* =========================================
   TOOLTIP
   ========================================= */
.tooltip {
  position: fixed;
  background: var(--bg-4);
  color: var(--text);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-xs);
  padding: 5px 9px;
  font-size: 0.75rem;
  font-weight: 600;
  pointer-events: none;
  z-index: 999;
  opacity: 0;
  transition: opacity 0.15s ease;
  white-space: nowrap;
  box-shadow: var(--shadow);
}

.tooltip.visible { opacity: 1; }

/* =========================================
   UTILITY
   ========================================= */
.text-muted { color: var(--text-2); font-size: 0.9rem; line-height: 1.5; }
.hidden { display: none !important; }

/* =========================================
   LONGEST STREAK BADGE
   ========================================= */
.longest-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: var(--accent-dim);
  color: var(--accent);
  border-radius: 99px;
  padding: 2px 8px;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* =========================================
   RIPPLE EFFECT
   ========================================= */
.ripple {
  position: absolute;
  border-radius: 50%;
  background: rgba(255,255,255,0.2);
  transform: scale(0);
  animation: ripple-anim 0.5s linear;
  pointer-events: none;
}

@keyframes ripple-anim {
  to { transform: scale(4); opacity: 0; }
}

/* =========================================
   RESPONSIVE
   ========================================= */
@media (max-width: 900px) {
  .main-layout {
    grid-template-columns: 1fr;
    padding: 16px;
    gap: 16px;
  }

  .sidebar {
    flex-direction: row;
    overflow-x: auto;
    gap: 12px;
  }

  .sidebar-card { flex-shrink: 0; min-width: 240px; }

  #insights-panel { min-width: 220px; }

  .reminder-banner { min-width: 200px; }
}

@media (max-width: 600px) {
  :root { --topbar-h: 56px; }

  .topbar { padding: 0 14px; }
  .logo-text { font-size: 1.1rem; }
  .date-display { display: none; }

  .btn-primary span:not(:first-child) { display: none; }
  .btn-primary span:first-child::after { content: ' Habit'; }

  .habits-grid { grid-template-columns: 1fr; }

  .tabs { overflow-x: auto; width: 100%; }

  .sidebar {
    flex-direction: column;
  }

  .sidebar-card { min-width: unset; }

  .form-row { grid-template-columns: 1fr; }

  .calendar-grid { gap: 4px; }
  .cal-date { font-size: 0.6rem; }
}

@media (max-width: 380px) {
  .topbar-right { gap: 6px; }
  .btn-primary { padding: 7px 10px; font-size: 0.8rem; }
}

/* =========================================
   ANIMATIONS
   ========================================= */
@keyframes confetti-fall {
  0% { transform: translateY(-20px) rotate(0deg); opacity: 1; }
  100% { transform: translateY(100vh) rotate(720deg); opacity: 0; }
}

/* Focus styles for accessibility */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}