:root {
  /* Color System - Light Mode (Default) */
  --snow-primary: oklch(0.65 0.12 230);
  --snow-primary-hover: oklch(0.6 0.14 230);
  --snow-bg: oklch(0.98 0.01 230);
  --snow-surface: oklch(1 0 0 / 0.85);
  --snow-surface-frost: oklch(1 0 0 / 0.6);
  --snow-ink: oklch(0.25 0.05 235);
  --snow-muted: oklch(0.45 0.04 235);
  --snow-border: oklch(0.25 0.05 235 / 0.1);
  --snow-accent: oklch(0.75 0.1 190);
  --snow-danger: oklch(0.6 0.18 25);
  --snow-success: oklch(0.7 0.12 150);

  /* Categories - Light */
  --category-programmers: oklch(0.65 0.12 230);
  --category-3d: oklch(0.7 0.12 160);
  --category-2d: oklch(0.75 0.14 45);
  --category-ui: oklch(0.7 0.15 300);
  --category-game: oklch(0.85 0.15 85);
  --category-audio: oklch(0.7 0.1 200);
  --category-vfx: oklch(0.7 0.2 330);

  /* Shadows & Depth */
  --shadow-drift: 0 8px 32px oklch(0.25 0.05 235 / 0.08);
  --shadow-pop: 0 16px 48px oklch(0.25 0.05 235 / 0.15);
  --glass-blur: blur(12px);

  /* Radius */
  --radius-xl: 32px;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;

  /* Spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 40px;
  --space-7: 64px;

  --transition-snow: 400ms cubic-bezier(0.2, 1, 0.3, 1);
}

[data-theme="dark"] {
  --snow-primary: oklch(0.75 0.12 230);
  --snow-primary-hover: oklch(0.8 0.14 230);
  --snow-bg: oklch(0.12 0.02 235);
  --snow-surface: oklch(0.18 0.03 235 / 0.85);
  --snow-surface-frost: oklch(0.18 0.03 235 / 0.6);
  --snow-ink: oklch(0.95 0.01 235);
  --snow-muted: oklch(0.7 0.02 235);
  --snow-border: oklch(0.95 0.01 235 / 0.12);
  --snow-accent: oklch(0.8 0.08 190);

  /* Categories - Dark (Slightly more vibrant) */
  --category-programmers: oklch(0.7 0.15 230);
  --category-3d: oklch(0.75 0.15 160);
  --category-2d: oklch(0.8 0.16 45);
  --category-ui: oklch(0.75 0.18 300);
  --category-game: oklch(0.9 0.18 85);
  --category-audio: oklch(0.75 0.12 200);
  --category-vfx: oklch(0.75 0.25 330);

  --shadow-drift: 0 8px 32px oklch(0 0 0 / 0.3);
  --shadow-pop: 0 16px 48px oklch(0 0 0 / 0.5);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100vh;
  font-family: "Lexend", "Inter", system-ui, sans-serif;
  color: var(--snow-ink);
  background: var(--snow-bg);
  transition: background-color var(--transition-snow), color var(--transition-snow);
  overflow-x: hidden;
}

.screen {
  display: none !important;
}

.screen-active {
  display: block !important;
}

#app-screen.screen-active {
  display: flex !important;
  flex-direction: column;
  gap: var(--space-5);
}

body {
  padding: var(--space-5);
  line-height: 1.5;
}

/* Background Atmosphere */
.app-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background: 
    radial-gradient(circle at 10% 20%, var(--snow-primary) 0%, transparent 40%),
    radial-gradient(circle at 90% 80%, var(--snow-accent) 0%, transparent 40%);
  opacity: 0.15;
  filter: blur(80px);
}

/* Typography Overrides */
h1, h2, h3, h4 {
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0;
}

.login-screen {
  min-height: calc(100vh - 2 * var(--space-5));
  display: grid;
  place-items: center;
}

.login-card {
  max-width: 480px;
  width: 100%;
  background: var(--snow-surface);
  backdrop-filter: var(--glass-blur);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-pop);
  border: 1px solid var(--snow-border);
  text-align: center;
}

.login-card h1 {
  background: linear-gradient(135deg, var(--snow-primary), var(--snow-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: var(--space-2);
}

.intro-copy {
  color: var(--snow-muted);
  margin-bottom: var(--space-5);
}

h2 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h3 { font-size: 1.1rem; color: var(--snow-muted); text-transform: uppercase; letter-spacing: 0.05em; }

/* Layout Grid - Asymmetric & Rhythmic */
.main-layout {
  display: grid;
  grid-template-columns: 280px 1fr 320px;
  gap: var(--space-5);
  align-items: start;
}

/* Panels - Frosty & Gamified */
.panel {
  background: var(--snow-surface);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--snow-border);
  border-radius: var(--radius-xl);
  padding: var(--space-5);
  box-shadow: var(--shadow-drift);
  transition: transform var(--transition-snow), box-shadow var(--transition-snow);
}

.panel:hover {
  box-shadow: var(--shadow-pop);
}

.panel-main {
  border-radius: var(--radius-xl);
  min-height: 600px;
}

.panel-section + .panel-section {
  margin-top: var(--space-6);
  padding-top: var(--space-5);
  border-top: 1px solid var(--snow-border);
}

/* Topbar - Level Progress Feel */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-5);
  padding: var(--space-4) var(--space-5);
  background: var(--snow-surface-frost);
  backdrop-filter: var(--glass-blur);
  border-radius: var(--radius-lg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--snow-border);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex: 1;
  justify-content: flex-end;
}

.progress-container {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 320px;
  flex-shrink: 0;
}

.label-tiny {
  font-size: 0.65rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--snow-muted);
  letter-spacing: 0.05em;
}

.view-toggle {
  display: flex;
  gap: var(--space-1);
  background: var(--snow-border);
  padding: var(--space-1);
  border-radius: 999px;
}

.topbar-main h2 {
  background: linear-gradient(135deg, var(--snow-primary), var(--snow-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* Global Progress - Map Path Style */
.global-progress {
  display: flex;
  gap: var(--space-1);
  background: var(--snow-border);
  padding: var(--space-1);
  border-radius: 999px;
  min-width: 300px;
}

.global-segment {
  flex: 1;
  padding: 8px 12px;
  text-align: center;
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  border-radius: 999px;
  transition: all var(--transition-snow);
  color: var(--snow-muted);
  position: relative;
  cursor: default;
}

.global-segment.active {
  background: var(--snow-primary);
  color: var(--snow-bg);
  box-shadow: 0 4px 20px var(--snow-primary / 0.4);
  transform: scale(1.05);
  z-index: 2;
}

.global-segment.active::after {
  content: '📍';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 1rem;
}

/* Buttons - Bubbled & Friendly */
.btn {
  border: 0;
  border-radius: 999px;
  padding: 10px 20px;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition-snow);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-primary {
  background: var(--snow-primary);
  color: var(--snow-bg);
  box-shadow: 0 8px 16px var(--snow-primary / 0.2);
}

.btn-primary:hover {
  background: var(--snow-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 12px 24px var(--snow-primary / 0.3);
}

.btn-ghost {
  background: transparent;
  color: var(--snow-ink);
  border: 1px solid var(--snow-border);
}

.btn-ghost:hover {
  background: var(--snow-border);
}

.btn-ghost.active {
  background: var(--snow-primary);
  color: var(--snow-bg);
  border-color: var(--snow-primary);
}

.btn-secondary.active {
  background: var(--snow-accent);
  color: var(--snow-bg);
  box-shadow: 0 0 15px var(--snow-accent / 0.6);
  animation: pulse-ice 2s infinite;
}

@keyframes pulse-ice {
  0% { box-shadow: 0 0 5px var(--snow-accent / 0.4); }
  50% { box-shadow: 0 0 20px var(--snow-accent / 0.8); }
  100% { box-shadow: 0 0 5px var(--snow-accent / 0.4); }
}

#app-screen.retro-mode-active::before {
  content: 'RETROSPECTIVE MODE ACTIVE';
  position: fixed;
  bottom: var(--space-5);
  right: var(--space-5);
  background: var(--snow-accent);
  color: var(--snow-bg);
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  z-index: 100;
  box-shadow: var(--shadow-pop);
  animation: slide-up 500ms var(--transition-snow);
}

@keyframes slide-up {
  from { transform: translateY(50px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

/* Theme Toggle Button */
.theme-toggle {
  width: 44px;
  height: 44px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--snow-surface);
  border: 1px solid var(--snow-border);
  color: var(--snow-ink);
  cursor: pointer;
  transition: all var(--transition-snow);
}

.theme-toggle:hover {
  transform: rotate(15deg) scale(1.1);
}

/* Task Cards - Drifting In */
.task-card {
  background: var(--snow-bg);
  border: 1px solid var(--snow-border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  margin-bottom: var(--space-4);
  position: relative;
  overflow: hidden;
  animation: drift-in 600ms var(--transition-snow);
}

@keyframes drift-in {
  from {
    opacity: 0;
    transform: translateX(20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.task-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--category-color, var(--snow-primary));
}

.status-badge {
  font-size: 0.7rem;
  font-weight: 800;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--snow-border);
}

.category-pill {
  font-size: 0.7rem;
  font-weight: 800;
  padding: 4px 10px;
  border-radius: 999px;
  color: var(--snow-bg);
}

/* Forms - Floating Fields */
.stacked-form, .task-form {
  display: grid;
  gap: var(--space-4);
}

label {
  display: grid;
  gap: var(--space-1);
  font-size: 0.85rem;
  font-weight: 600;
}

input, select, textarea {
  width: 100%;
  background: var(--snow-bg);
  border: 1px solid var(--snow-border);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  color: var(--snow-ink);
  transition: all var(--transition-snow);
}

input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--snow-primary);
  box-shadow: 0 0 0 4px var(--snow-primary / 0.1);
}

/* Animations & Polishes */
.reveal-card {
  animation: rise-in 800ms var(--transition-snow);
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Responsive Overrides */
@media (max-width: 1200px) {
  .main-layout {
    grid-template-columns: 1fr;
    max-width: 800px;
    margin: 0 auto;
  }
  
  .panel-left, .panel-right {
    order: 2;
  }
}

@media (max-width: 768px) {
  body { padding: var(--space-3); }
  .topbar { flex-direction: column; gap: var(--space-4); }
  .global-progress { width: 100%; min-width: 0; }
}

/* Category Variable Mapping */
.category-programming { --category-color: var(--category-programmers); }
.category-modeling { --category-color: var(--category-3d); }
.category-illustrating { --category-color: var(--category-2d); }
.category-ui-designing { --category-color: var(--category-ui); }
.category-game-designing { --category-color: var(--category-game); }
.category-audio-engineering { --category-color: var(--category-audio); }
.category-vfx-designing { --category-color: var(--category-vfx); }

.category-pill.category-programming { background: var(--category-programmers); }
.category-pill.category-modeling { background: var(--category-3d); }
.category-pill.category-illustrating { background: var(--category-2d); }
.category-pill.category-ui-designing { background: var(--category-ui); }
.category-pill.category-game-designing { background: var(--category-game); color: oklch(0.2 0.05 85); }
.category-pill.category-audio-engineering { background: var(--category-audio); color: oklch(0.2 0.05 200); }
.category-pill.category-vfx-designing { background: var(--category-vfx); color: white; }

/* Modals - Frosty Overlays */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: oklch(0.12 0.02 235 / 0.6);
  backdrop-filter: blur(8px);
  display: grid;
  place-items: center;
  padding: var(--space-4);
  z-index: 1000;
  animation: fade-in 300ms ease-out;
}

.modal-card {
  width: min(560px, 100%);
  background: var(--snow-surface);
  backdrop-filter: var(--glass-blur);
  border-radius: var(--radius-xl);
  border: 1px solid var(--snow-border);
  box-shadow: var(--shadow-pop);
  padding: var(--space-6);
  display: grid;
  gap: var(--space-4);
  animation: rise-in 500ms var(--transition-snow);
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

@keyframes fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Progress Bars - Ice & Water Fill */
.progress-shell {
  border-radius: 999px;
  background: var(--snow-border);
  overflow: hidden;
  position: relative;
  height: 12px;
  margin: var(--space-2) 0;
}

.progress-earned {
  height: 100%;
  background: linear-gradient(90deg, var(--snow-primary), var(--snow-accent));
  transition: width 1s var(--transition-snow);
}

.progress-potential {
  position: absolute;
  top: 0;
  bottom: 0;
  background: repeating-linear-gradient(
    110deg,
    oklch(1 0 0 / 0.1) 0,
    oklch(1 0 0 / 0.1) 10px,
    oklch(1 0 0 / 0.2) 10px,
    oklch(1 0 0 / 0.2) 20px
  );
  animation: ice-shimmer 2s linear infinite;
}

@keyframes ice-shimmer {
  from { background-position: 0 0; }
  to { background-position: 40px 0; }
}

/* Utility Tiles & Notes */
.note-tile {
  background: var(--snow-surface-frost);
  backdrop-filter: var(--glass-blur);
  border-radius: var(--radius-sm);
  border: 1px solid var(--snow-border);
  padding: var(--space-3);
  font-size: 0.88rem;
  transition: all var(--transition-snow);
}

.note-tile:hover {
  background: var(--snow-surface);
  transform: scale(1.02);
}

/* Urgency Levels */
.urgency-item { font-weight: 800; }
.urgency-low { color: oklch(0.6 0.1 20); }
.urgency-medium { color: oklch(0.5 0.15 20); }
.urgency-high { color: oklch(0.4 0.2 20); }
.urgency-critical { color: oklch(0.3 0.25 20); text-transform: uppercase; }

/* Status & Feedback */
.error-text { color: var(--snow-danger); font-size: 0.85rem; min-height: 1.2em; }
.status-text { color: var(--snow-muted); font-size: 0.85rem; }

/* Empty States */
.empty-state {
  color: var(--snow-muted);
  font-size: 0.85rem;
  background: var(--snow-border);
  padding: var(--space-4);
  border-radius: var(--radius-sm);
  text-align: center;
  border: 1px dashed var(--snow-muted / 0.3);
}

/* Retrospective Table */
.retro-table { display: grid; gap: var(--space-2); }
.retro-row {
  display: grid;
  grid-template-columns: 1fr 100px;
  gap: var(--space-3);
  align-items: center;
  background: var(--snow-surface-frost);
  border-radius: var(--radius-sm);
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--snow-border);
}

/* Task Specifics */
.subtask-list { display: grid; gap: var(--space-2); margin-top: var(--space-3); }
.subtask-row { display: flex; align-items: center; gap: var(--space-2); font-size: 0.85rem; }
.subtask-row label { display: flex; align-items: center; gap: var(--space-2); cursor: pointer; }
.inline-input-row { display: flex; gap: var(--space-2); margin-top: var(--space-3); }
.inline-input-row input { flex: 1; }