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

:root {
  --bg-primary: #030712;
  --bg-secondary: #0a0f1e;
  --bg-tertiary: #0e1530;
  --bg-card: rgba(12, 20, 45, 0.7);
  --bg-card-hover: rgba(18, 28, 58, 0.85);
  --bg-input: #060b18;
  --bg-glass: rgba(12, 20, 45, 0.5);
  --border-color: rgba(168, 85, 247, 0.08);
  --border-hover: rgba(168, 85, 247, 0.2);
  --border-accent: rgba(168, 85, 247, 0.2);
  --text-primary: #eef2ff;
  --text-secondary: #94a3c8;
  --text-muted: #4a5580;
  --accent-blue: #6366f1;
  --accent-cyan: #06b6d4;
  --accent-green: #10b981;
  --accent-orange: #f59e0b;
  --accent-purple: #a855f7;
  --accent-pink: #ec4899;
  --accent-red: #ef4444;
  --neon-purple: #c084fc;
  --neon-pink: #f472b6;
  --neon-blue: #818cf8;
  --neon-green: #34d399;
  --neon-cyan: #22d3ee;
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-card:
    0 4px 32px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(168, 85, 247, 0.04);
  --shadow-glow: 0 0 40px rgba(168, 85, 247, 0.1);
  --shadow-neon:
    0 0 30px rgba(168, 85, 247, 0.15), 0 0 60px rgba(236, 72, 153, 0.05);
  --shadow-modal:
    0 40px 120px rgba(0, 0, 0, 0.8), 0 0 80px rgba(168, 85, 247, 0.05);
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 18px;
  --radius-xl: 22px;
  --radius-full: 9999px;
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-spring: cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

body {
  font-family:
    "Inter",
    -apple-system,
    BlinkMacSystemFont,
    sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== Splash Screen ===== */
.splash-screen {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: #030712;
  display: flex;
  align-items: center;
  justify-content: center;
  transition:
    opacity 0.6s ease,
    visibility 0.6s ease;
}
.splash-screen.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.splash-content {
  text-align: center;
  animation: splashFadeIn 0.8s ease both;
}
@keyframes splashFadeIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}
.splash-logo {
  width: 80px;
  height: 80px;
  margin: 0 auto 20px;
  background: linear-gradient(
    135deg,
    rgba(168, 85, 247, 0.12),
    rgba(236, 72, 153, 0.1)
  );
  border: 1px solid rgba(168, 85, 247, 0.15);
  border-radius: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow:
    0 0 40px rgba(168, 85, 247, 0.15),
    0 0 80px rgba(236, 72, 153, 0.08);
  animation: splashLogoPulse 2s ease-in-out infinite alternate;
}
@keyframes splashLogoPulse {
  0% {
    box-shadow:
      0 0 40px rgba(168, 85, 247, 0.15),
      0 0 80px rgba(236, 72, 153, 0.08);
  }
  100% {
    box-shadow:
      0 0 50px rgba(168, 85, 247, 0.25),
      0 0 100px rgba(236, 72, 153, 0.12);
  }
}
.splash-title {
  font-size: 2.2rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  background: linear-gradient(135deg, #fff 0%, #c084fc 50%, #f472b6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 6px;
  filter: drop-shadow(0 0 20px rgba(168, 85, 247, 0.3));
}
.splash-tagline {
  font-size: 0.85rem;
  color: #4a5580;
  font-weight: 500;
  letter-spacing: 0.04em;
  margin-bottom: 24px;
}
.splash-features {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin-bottom: 32px;
}
.splash-chip {
  padding: 6px 14px;
  background: rgba(168, 85, 247, 0.08);
  border: 1px solid rgba(168, 85, 247, 0.12);
  border-radius: 20px;
  font-size: 0.72rem;
  font-weight: 600;
  color: #94a3c8;
  animation: splashChipIn 0.6s ease both;
}
.splash-chip:nth-child(1) {
  animation-delay: 0.3s;
}
.splash-chip:nth-child(2) {
  animation-delay: 0.45s;
}
.splash-chip:nth-child(3) {
  animation-delay: 0.6s;
}
@keyframes splashChipIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.splash-loader {
  width: 160px;
  height: 3px;
  background: rgba(168, 85, 247, 0.1);
  border-radius: 3px;
  margin: 0 auto;
  overflow: hidden;
}
.splash-loader-bar {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, #a855f7, #ec4899, #a855f7);
  background-size: 200% 100%;
  border-radius: 3px;
  animation:
    splashLoad 1.8s ease forwards,
    splashShimmer 1s linear infinite;
}
@keyframes splashLoad {
  0% {
    width: 0%;
  }
  40% {
    width: 60%;
  }
  80% {
    width: 90%;
  }
  100% {
    width: 100%;
  }
}
@keyframes splashShimmer {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.08);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.14);
}
::selection {
  background: rgba(139, 92, 246, 0.3);
  color: #fff;
}

/* ===== Header ===== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 32px;
  background: rgba(6, 10, 24, 0.8);
  backdrop-filter: blur(24px) saturate(1.6);
  -webkit-backdrop-filter: blur(24px) saturate(1.6);
  border-bottom: 1px solid rgba(168, 85, 247, 0.06);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(168, 85, 247, 0.2),
    rgba(236, 72, 153, 0.2),
    transparent
  );
}
.header-left {
  display: flex;
  flex-direction: column;
}
.header-center {
  display: flex;
  align-items: center;
  justify-content: center;
}
.header-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-row {
  display: flex;
  align-items: center;
  gap: 12px;
}
.logo-icon {
  width: 42px;
  height: 42px;
  background: linear-gradient(
    135deg,
    rgba(168, 85, 247, 0.15),
    rgba(236, 72, 153, 0.12)
  );
  border: 1px solid rgba(168, 85, 247, 0.2);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow:
    0 0 20px rgba(168, 85, 247, 0.1),
    inset 0 0 20px rgba(168, 85, 247, 0.05);
}
.header h1 {
  font-size: 1.3rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  background: linear-gradient(
    135deg,
    #fff 0%,
    var(--neon-purple) 50%,
    var(--neon-pink) 100%
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  filter: drop-shadow(0 0 12px rgba(168, 85, 247, 0.3));
}
.subtitle {
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-top: 1px;
  letter-spacing: 0.03em;
  font-weight: 500;
}

/* ===== Buttons ===== */
.btn-back {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: rgba(59, 130, 246, 0.06);
  border: 1px solid rgba(59, 130, 246, 0.15);
  color: #60a5fa;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.25s var(--ease);
}
.btn-back:hover {
  background: rgba(59, 130, 246, 0.12);
  border-color: rgba(59, 130, 246, 0.3);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.1);
}

/* ===== Floating Action Button ===== */
.fab {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 58px;
  height: 58px;
  border-radius: 50%;
  background: linear-gradient(135deg, #a855f7, #7c3aed);
  border: none;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 150;
  box-shadow:
    0 6px 32px rgba(168, 85, 247, 0.45),
    0 0 40px rgba(168, 85, 247, 0.15),
    inset 0 1px 0 rgba(255, 255, 255, 0.15);
  transition: all 0.3s var(--ease);
  animation: fabGlow 3s ease-in-out infinite alternate;
}
@keyframes fabGlow {
  0% {
    box-shadow:
      0 6px 32px rgba(168, 85, 247, 0.4),
      0 0 40px rgba(168, 85, 247, 0.1);
  }
  100% {
    box-shadow:
      0 6px 32px rgba(236, 72, 153, 0.5),
      0 0 60px rgba(236, 72, 153, 0.15);
  }
}
.fab:hover {
  transform: translateY(-3px) scale(1.08);
  box-shadow:
    0 10px 50px rgba(168, 85, 247, 0.55),
    0 0 0 6px rgba(168, 85, 247, 0.08),
    0 0 60px rgba(168, 85, 247, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
}
.fab:active {
  transform: translateY(-1px) scale(0.97);
}

.btn-theme {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.25s var(--ease);
}
.btn-theme:hover {
  background: var(--bg-card-hover);
  color: var(--text-primary);
  border-color: var(--border-hover);
  transform: translateY(-1px);
}

/* ===== Streak Button ===== */
.btn-streak {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: rgba(245, 158, 11, 0.04);
  border: 1px solid rgba(245, 158, 11, 0.1);
  color: var(--text-muted);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.3s var(--ease);
}
.btn-streak:hover {
  background: rgba(245, 158, 11, 0.08);
  border-color: rgba(245, 158, 11, 0.2);
  color: var(--text-secondary);
  transform: translateY(-1px);
}
.btn-streak .streak-count {
  font-weight: 800;
  font-size: 0.9rem;
  color: var(--text-muted);
  min-width: 14px;
  text-align: center;
  transition: color 0.3s;
}
.btn-streak .streak-label {
  font-size: 0.66rem;
  color: var(--text-muted);
  font-weight: 500;
}
.btn-streak.streak-active {
  background: rgba(245, 158, 11, 0.08);
  border-color: rgba(245, 158, 11, 0.25);
  color: #fbbf24;
}
.btn-streak.streak-active .streak-count {
  color: #fbbf24;
  text-shadow: 0 0 12px rgba(245, 158, 11, 0.4);
}
.btn-streak.streak-active .streak-label {
  color: #fbbf24;
}
.btn-streak.streak-active svg {
  color: #fbbf24;
  filter: drop-shadow(0 0 4px rgba(245, 158, 11, 0.4));
}
.btn-streak.streak-risk {
  border-color: rgba(239, 68, 68, 0.2);
  animation: streakPulse 2s ease-in-out infinite;
}
.btn-streak.streak-risk .streak-count {
  color: var(--accent-orange);
}
.btn-streak.streak-risk svg {
  color: var(--accent-orange);
}
@keyframes streakPulse {
  0%,
  100% {
    border-color: rgba(239, 68, 68, 0.12);
  }
  50% {
    border-color: rgba(245, 158, 11, 0.35);
  }
}

/* ===== Stats Bar ===== */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  padding: 18px 32px;
  border-bottom: 1px solid var(--border-color);
  background: rgba(10, 16, 32, 0.35);
}
.stat-card {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: all 0.25s var(--ease);
  backdrop-filter: blur(8px);
}
.stat-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-card);
}
.stat-icon {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
}
.si-total {
  color: var(--accent-purple);
  background: rgba(139, 92, 246, 0.1);
}
.si-done {
  color: var(--accent-green);
  background: rgba(16, 185, 129, 0.1);
}
.si-best {
  color: var(--accent-orange);
  background: rgba(245, 158, 11, 0.1);
}
.si-rate {
  color: var(--accent-cyan);
  background: rgba(6, 182, 212, 0.1);
}
.stat-info {
  display: flex;
  flex-direction: column;
}
.stat-num {
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}
.stat-label {
  font-size: 0.62rem;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* ===== Main Content ===== */
.main-content {
  padding: 28px 32px;
  position: relative;
  z-index: 1;
}

/* ===== Section Headers ===== */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-color);
}
.section-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-title svg {
  color: var(--accent-purple);
}
.section-sub {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 500;
}
.habits-section {
  margin-bottom: 36px;
}

/* ===== Habits Grid ===== */
.habits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 16px;
}

/* ===== Habit Card ===== */
.habit-card {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 22px;
  transition: all 0.3s var(--ease);
  animation: cardSlideIn 0.45s var(--ease-bounce) both;
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(12px);
}
.habit-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(
    90deg,
    transparent,
    var(--habit-color),
    transparent
  );
  opacity: 0.5;
  transition: opacity 0.3s;
}
.habit-card::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(
    ellipse at top,
    color-mix(in srgb, var(--habit-color) 4%, transparent),
    transparent 70%
  );
  pointer-events: none;
  transition: opacity 0.3s;
  opacity: 0;
}
.habit-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-hover);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card), var(--shadow-neon);
}
.habit-card:hover::before {
  opacity: 1;
}
.habit-card:hover::after {
  opacity: 1;
}

@keyframes cardSlideIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.97);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.habit-card-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
  position: relative;
  z-index: 1;
}
.habit-icon {
  font-size: 1.35rem;
  width: 46px;
  height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--habit-color) 10%, transparent);
  border: 1px solid color-mix(in srgb, var(--habit-color) 12%, transparent);
  flex-shrink: 0;
}
.habit-info {
  flex: 1;
  min-width: 0;
}
.habit-name {
  font-size: 0.92rem;
  font-weight: 700;
  margin-bottom: 3px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.habit-freq {
  font-size: 0.6rem;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.habit-delete {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 7px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
  opacity: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.habit-card:hover .habit-delete {
  opacity: 1;
}
.habit-delete:hover {
  color: var(--accent-red);
  background: rgba(239, 68, 68, 0.08);
}

/* ===== Habit Streak Row ===== */
.habit-streak-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  position: relative;
  z-index: 1;
}
.habit-streak-badge {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.66rem;
  font-weight: 700;
  color: var(--accent-orange);
  background: rgba(245, 158, 11, 0.06);
  padding: 5px 12px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(245, 158, 11, 0.1);
}
.habit-streak-badge svg {
  width: 11px;
  height: 11px;
}
.habit-streak-badge.no-streak {
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.02);
  border-color: var(--border-color);
}
.habit-best-badge {
  font-size: 0.6rem;
  color: var(--text-muted);
  font-weight: 600;
  background: rgba(255, 255, 255, 0.02);
  padding: 5px 10px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
}
.habit-completion-badge {
  margin-left: auto;
  font-size: 0.7rem;
  font-weight: 800;
  color: var(--habit-color);
  letter-spacing: -0.02em;
}

/* ===== Week Grid ===== */
.habit-week {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 6px;
  margin-bottom: 16px;
  position: relative;
  z-index: 1;
}
.habit-day {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 5px;
  cursor: pointer;
  transition: all 0.2s;
}
.habit-day-label {
  font-size: 0.5rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.habit-day-circle {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 2px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s var(--ease);
  position: relative;
}
.habit-day-circle:hover {
  border-color: var(--border-hover);
  transform: scale(1.12);
}
.habit-day.checked .habit-day-circle {
  background: var(--habit-color);
  border-color: var(--habit-color);
  box-shadow:
    0 0 20px color-mix(in srgb, var(--habit-color) 45%, transparent),
    0 0 40px color-mix(in srgb, var(--habit-color) 15%, transparent);
}
.habit-day.checked .habit-day-circle svg {
  opacity: 1;
}
.habit-day-circle svg {
  opacity: 0;
  transition: opacity 0.2s;
}
.habit-day.today .habit-day-label {
  color: var(--accent-purple);
  font-weight: 800;
}
.habit-day.today .habit-day-circle {
  border-color: rgba(139, 92, 246, 0.4);
  box-shadow: 0 0 12px rgba(139, 92, 246, 0.15);
}
.habit-day.today.checked .habit-day-circle {
  border-color: var(--habit-color);
}
.habit-day.disabled {
  opacity: 0.2;
  pointer-events: none;
}

/* ===== Progress Bar ===== */
.habit-progress {
  display: flex;
  align-items: center;
  gap: 10px;
  position: relative;
  z-index: 1;
}
.habit-progress-bar {
  flex: 1;
  height: 4px;
  background: rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-full);
  overflow: hidden;
}
.habit-progress-fill {
  height: 100%;
  border-radius: var(--radius-full);
  transition: width 0.5s var(--ease-spring);
  background: var(--habit-color);
  box-shadow: 0 0 8px color-mix(in srgb, var(--habit-color) 30%, transparent);
}
.habit-progress-text {
  font-size: 0.64rem;
  font-weight: 700;
  color: var(--text-muted);
  min-width: 32px;
  text-align: right;
}

/* ===== GitHub-style Contribution Graph ===== */
.heatmap-section {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 22px 28px;
  backdrop-filter: blur(12px);
  display: flex;
  flex-direction: column;
  align-items: center;
  width: fit-content;
  margin: 0 auto;
  max-width: 100%;
  overflow: hidden;
}
.heatmap-section .section-header {
  border-bottom: none;
  margin-bottom: 8px;
  padding-bottom: 0;
  width: 100%;
}
.heat-range {
  font-size: 0.65rem;
  color: var(--text-muted);
  font-weight: 500;
}
.heat-graph-wrap {
  display: flex;
  justify-content: center;
  overflow: hidden;
}
.heat-content {
  display: inline-flex;
  flex-direction: column;
  overflow: hidden;
  padding: 4px;
}
.heat-grid {
  display: grid;
  gap: 3px;
  width: fit-content;
}
.heat-months {
  display: grid;
  margin-top: 6px;
  width: fit-content;
}
.heat-month-label {
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--text-secondary);
  letter-spacing: 0.02em;
}
.heatmap-cell {
  width: 13px;
  height: 13px;
  border-radius: 3px;
  border: 1px solid transparent;
  transition: all 0.15s var(--ease);
  cursor: default;
}
.heatmap-cell:hover {
  border-color: var(--border-hover);
  z-index: 2;
}
.heatmap-cell.level-0 {
  background: rgba(255, 255, 255, 0.06);
}
.heatmap-cell.level-1 {
  background: rgba(34, 197, 94, 0.3);
}
.heatmap-cell.level-2 {
  background: rgba(34, 197, 94, 0.5);
}
.heatmap-cell.level-3 {
  background: rgba(34, 197, 94, 0.75);
  box-shadow: 0 0 4px rgba(34, 197, 94, 0.3);
}
.heatmap-cell.level-4 {
  background: #22c55e;
  box-shadow: 0 0 8px rgba(34, 197, 94, 0.4);
}
.heatmap-cell.today-cell {
  outline: 1px solid rgba(168, 85, 247, 0.2);
}
.heatmap-cell.empty-cell {
  background: transparent;
  border: none;
  pointer-events: none;
}
.heatmap-cell.future-cell {
  opacity: 0.4;
}
/* Tooltip — always below the cell */
.heatmap-cell[data-tip] {
  position: relative;
}
.heatmap-cell[data-tip]::after {
  content: attr(data-tip);
  position: absolute;
  top: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  background: rgba(10, 14, 28, 0.95);
  color: #edf2fc;
  font-size: 0.62rem;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: 6px;
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.15s,
    visibility 0.15s;
  z-index: 20;
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
}
/* Bottom rows: show above instead */
.heatmap-cell.tip-up[data-tip]::after {
  top: auto;
  bottom: calc(100% + 6px);
}
/* Left-edge: anchor right */
.heatmap-cell.tip-right[data-tip]::after {
  left: 0;
  transform: translateX(0);
}
/* Right-edge: anchor left */
.heatmap-cell.tip-left[data-tip]::after {
  left: auto;
  right: 0;
  transform: translateX(0);
}
.heatmap-cell[data-tip]:hover::after {
  opacity: 1;
  visibility: visible;
}
[data-theme="light"] .heatmap-cell[data-tip]::after {
  background: rgba(255, 255, 255, 0.95);
  color: #1a1f35;
  border-color: rgba(0, 0, 0, 0.08);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}
.heat-legend {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 3px;
  margin-top: 8px;
}
.heat-leg-label {
  font-size: 0.5rem;
  color: var(--text-muted);
  font-weight: 500;
  padding: 0 3px;
}
.heat-leg-cell {
  width: 13px;
  height: 13px;
  border-radius: 3px;
}
.heat-leg-cell.level-0 {
  background: rgba(255, 255, 255, 0.06);
}
.heat-leg-cell.level-1 {
  background: rgba(34, 197, 94, 0.3);
}
.heat-leg-cell.level-2 {
  background: rgba(34, 197, 94, 0.5);
}
.heat-leg-cell.level-3 {
  background: rgba(34, 197, 94, 0.75);
}
.heat-leg-cell.level-4 {
  background: #22c55e;
}

/* ===== Empty State ===== */
.empty-state {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 80px 20px;
  text-align: center;
}
.empty-state.visible {
  display: flex;
}
.empty-icon-wrap {
  opacity: 0.6;
}
.empty-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-secondary);
}
.empty-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}
.empty-desc .hl {
  color: var(--accent-purple);
  font-weight: 600;
}

/* ===== Modal ===== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.35s var(--ease);
}
.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}
.modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 30px 34px;
  width: 90%;
  max-width: 480px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-modal);
  transform: translateY(30px) scale(0.95);
  transition: all 0.4s var(--ease-bounce);
}
.modal-overlay.active .modal {
  transform: translateY(0) scale(1);
}
.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 26px;
}
.modal-header h2 {
  font-size: 1.1rem;
  font-weight: 700;
}
.modal-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
  line-height: 1;
}
.modal-close:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

/* ===== Form ===== */
.form-group {
  margin-bottom: 18px;
  flex: 1;
}
.form-group label {
  display: block;
  font-size: 0.76rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}
.form-row {
  display: flex;
  gap: 14px;
}
input[type="text"],
select {
  width: 100%;
  padding: 11px 16px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.84rem;
  transition: all 0.25s var(--ease);
  outline: none;
}
input:focus,
select:focus {
  border-color: var(--accent-purple);
  box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.1);
}
input::placeholder {
  color: var(--text-muted);
}
select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M3 5l3 3 3-3' stroke='%234a5a7a' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 34px;
}
.form-actions {
  display: flex;
  gap: 10px;
  margin-top: 24px;
}
.btn-create {
  padding: 11px 26px;
  background: linear-gradient(135deg, var(--accent-purple), #7c3aed);
  border: none;
  color: #fff;
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.3s var(--ease);
  box-shadow:
    0 4px 20px rgba(139, 92, 246, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
}
.btn-create:hover {
  box-shadow: 0 6px 28px rgba(139, 92, 246, 0.4);
  transform: translateY(-1px);
}
.btn-cancel {
  padding: 11px 22px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-cancel:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-primary);
  border-color: var(--border-hover);
}

/* ===== Focus Visible ===== */
button:focus-visible,
input:focus-visible,
select:focus-visible,
a:focus-visible {
  outline: 2px solid var(--accent-purple);
  outline-offset: 2px;
}

/* ===== Smooth Theme Transition ===== */
body,
.header,
.stats-bar,
.stat-card,
.habit-card,
.modal,
.heatmap-section,
.btn-streak,
.btn-theme,
.fab,
.heatmap-cell,
input,
select {
  transition:
    background 0.4s var(--ease),
    color 0.4s var(--ease),
    border-color 0.4s var(--ease),
    box-shadow 0.4s var(--ease);
}

/* ===== LIGHT THEME ===== */
[data-theme="light"] {
  --bg-primary: #f4f6fb;
  --bg-secondary: #ffffff;
  --bg-tertiary: #edf0f8;
  --bg-card: rgba(255, 255, 255, 0.7);
  --bg-card-hover: rgba(240, 244, 255, 0.9);
  --bg-input: #f4f6fb;
  --bg-glass: rgba(255, 255, 255, 0.55);
  --border-color: rgba(0, 0, 0, 0.06);
  --border-hover: rgba(0, 0, 0, 0.12);
  --border-accent: rgba(139, 92, 246, 0.15);
  --text-primary: #1a1f35;
  --text-secondary: #4a5568;
  --text-muted: #8896ab;
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.06), 0 0 0 1px rgba(0, 0, 0, 0.03);
  --shadow-glow: 0 0 30px rgba(139, 92, 246, 0.04);
  --shadow-modal:
    0 30px 80px rgba(0, 0, 0, 0.12), 0 0 0 1px rgba(0, 0, 0, 0.05);
}
[data-theme="light"] body {
  background: var(--bg-primary);
}
[data-theme="light"] .header {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(24px) saturate(1.4);
}
[data-theme="light"] .header::after {
  background: linear-gradient(
    90deg,
    transparent,
    rgba(168, 85, 247, 0.1),
    rgba(236, 72, 153, 0.1),
    transparent
  );
}
[data-theme="light"] .header h1 {
  background: linear-gradient(135deg, #1a1f35 20%, #7c3aed 80%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  filter: none;
}
[data-theme="light"] .stats-bar {
  background: rgba(255, 255, 255, 0.4);
}
[data-theme="light"] .stat-card {
  background: rgba(255, 255, 255, 0.6);
  box-shadow: var(--shadow-xs);
}
[data-theme="light"] .habit-card {
  background: rgba(255, 255, 255, 0.6);
  border-color: var(--border-color);
  box-shadow: var(--shadow-xs);
  backdrop-filter: blur(8px);
}
[data-theme="light"] .habit-card:hover {
  background: rgba(255, 255, 255, 0.85);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
}
[data-theme="light"] .heatmap-section {
  background: rgba(255, 255, 255, 0.6);
  box-shadow: var(--shadow-xs);
}
[data-theme="light"] .heatmap-cell.level-0 {
  background: rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .heatmap-cell.level-1 {
  background: rgba(34, 197, 94, 0.25);
}
[data-theme="light"] .heatmap-cell.level-2 {
  background: rgba(34, 197, 94, 0.45);
}
[data-theme="light"] .heatmap-cell.level-3 {
  background: rgba(34, 197, 94, 0.65);
}
[data-theme="light"] .heatmap-cell.level-4 {
  background: #22c55e;
}
[data-theme="light"] .heat-leg-cell.level-0 {
  background: rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .heat-leg-cell.level-1 {
  background: rgba(34, 197, 94, 0.25);
}
[data-theme="light"] .heat-leg-cell.level-2 {
  background: rgba(34, 197, 94, 0.45);
}
[data-theme="light"] .heat-leg-cell.level-3 {
  background: rgba(34, 197, 94, 0.65);
}
[data-theme="light"] .heat-leg-cell.level-4 {
  background: #22c55e;
}
[data-theme="light"] .modal {
  background: #fff;
}
[data-theme="light"] .btn-theme {
  background: var(--bg-tertiary);
}
[data-theme="light"] .btn-theme:hover {
  background: var(--bg-card-hover);
  color: var(--accent-orange);
}
[data-theme="light"] .btn-streak {
  background: rgba(245, 158, 11, 0.04);
  border-color: rgba(245, 158, 11, 0.15);
}
[data-theme="light"] .habit-streak-badge {
  background: rgba(245, 158, 11, 0.05);
}
[data-theme="light"] .habit-best-badge {
  background: rgba(0, 0, 0, 0.02);
}
[data-theme="light"] .btn-cancel {
  background: rgba(0, 0, 0, 0.02);
}
[data-theme="light"] .btn-cancel:hover {
  background: rgba(0, 0, 0, 0.04);
}
[data-theme="light"] .fab {
  box-shadow:
    0 6px 24px rgba(168, 85, 247, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  animation: none;
}
[data-theme="light"] .fab:hover {
  box-shadow:
    0 10px 36px rgba(168, 85, 247, 0.3),
    0 0 0 6px rgba(168, 85, 247, 0.06),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
}
[data-theme="light"] ::selection {
  background: rgba(139, 92, 246, 0.2);
  color: #1a1f35;
}
[data-theme="light"] ::-webkit-scrollbar-thumb {
  background: rgba(0, 0, 0, 0.1);
}
[data-theme="light"] ::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 0, 0, 0.18);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .header {
    padding: 14px 16px;
    flex-wrap: wrap;
    gap: 10px;
  }
  .header-left {
    width: 100%;
  }
  .header-center {
    order: 3;
    width: 100%;
    justify-content: center;
  }
  .header-right {
    margin-left: auto;
  }
  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    padding: 14px 16px;
    gap: 10px;
  }
  .main-content {
    padding: 18px 16px;
  }
  .habits-grid {
    grid-template-columns: 1fr;
  }
  .modal {
    padding: 22px;
    width: 95%;
  }
  .form-row {
    flex-direction: column;
    gap: 0;
  }
}
@media (max-width: 480px) {
  .stats-bar {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }
  .stat-card {
    padding: 10px 12px;
  }
  .header-right {
    width: 100%;
    justify-content: flex-end;
  }
  .habit-day-circle {
    width: 30px;
    height: 30px;
  }
  .fab {
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
  }
}