/* ============================================================
   HabitQuest – Minimalist Habit Tracker
   style.css
   ============================================================
   Table of Contents
   1. CSS Custom Properties (Design Tokens)
   2. Reset & Base
   3. Layout / App Wrapper
   4. Header
   5. Stats Bar
   6. XP Progress Bar
   7. Task Input
   8. Task List & Items
   9. Suggestion Chips
   10. Footer
   11. Toast Notification
   12. Celebration Overlay
   13. Animations & Transitions
   14. Responsive (Mobile)
   ============================================================ */


/* ── 1. CSS Custom Properties ────────────────────────────── */
:root {
  /* Colour palette */
  --clr-bg:          #0f1117;
  --clr-surface:     #1a1d27;
  --clr-surface-alt: #22263a;
  --clr-border:      #2e3350;
  --clr-accent:      #7c6af7;
  --clr-accent-2:    #5ec4ff;
  --clr-accent-glow: rgba(124, 106, 247, 0.35);
  --clr-success:     #4ade80;
  --clr-success-bg:  rgba(74, 222, 128, 0.08);
  --clr-danger:      #f87171;
  --clr-text:        #e8eaf6;
  --clr-text-muted:  #7b82a3;
  --clr-check:       #7c6af7;

  /* Typography */
  --font:            'Inter', system-ui, sans-serif;
  --fs-xs:           0.7rem;
  --fs-sm:           0.82rem;
  --fs-base:         0.95rem;
  --fs-md:           1.1rem;
  --fs-lg:           1.4rem;
  --fs-xl:           2rem;

  /* Spacing */
  --sp-xs:  4px;
  --sp-sm:  8px;
  --sp-md:  16px;
  --sp-lg:  24px;
  --sp-xl:  32px;

  /* Border radius */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 999px;

  /* Shadows */
  --shadow-card: 0 2px 20px rgba(0,0,0,0.4);
  --shadow-glow: 0 0 24px var(--clr-accent-glow);

  /* Transitions */
  --transition: 0.2s ease;
}


/* ── 2. Reset & Base ──────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  font-size: var(--fs-base);
  background: var(--clr-bg);
  color: var(--clr-text);
  min-height: 100dvh;
  /* subtle grid texture */
  background-image: radial-gradient(circle at 18% 20%, rgba(124,106,247,0.06) 0%, transparent 55%),
                    radial-gradient(circle at 82% 80%, rgba(94,196,255,0.05) 0%, transparent 55%);
  -webkit-font-smoothing: antialiased;
}

button { cursor: pointer; border: none; background: none; font-family: inherit; }
input  { font-family: inherit; }
ul, ol { list-style: none; }
a  { color: inherit; text-decoration: none; }


/* ── 3. Layout / App Wrapper ─────────────────────────────── */
.app-wrapper {
  max-width: 560px;
  margin: 0 auto;
  padding: var(--sp-lg) var(--sp-md) calc(var(--sp-xl) * 2);
  display: flex;
  flex-direction: column;
  gap: var(--sp-lg);
}


/* ── 4. Header ───────────────────────────────────────────── */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
}

.brand-icon { font-size: 1.5rem; }

.brand-name {
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, var(--clr-accent), var(--clr-accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.today-date {
  font-size: var(--fs-sm);
  color: var(--clr-text-muted);
  font-weight: 400;
}


/* ── 5. Stats Bar ────────────────────────────────────────── */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-sm);
}

.stat-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  padding: var(--sp-md) var(--sp-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.stat-card:hover {
  border-color: var(--clr-accent);
  box-shadow: var(--shadow-glow);
}

.stat-label {
  font-size: var(--fs-xs);
  color: var(--clr-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  font-weight: 500;
}

.stat-value {
  font-size: var(--fs-xl);
  font-weight: 700;
  line-height: 1;
  color: var(--clr-text);
}

/* Level card gets accent colour */
.stat-level { border-color: var(--clr-accent); }
.level-value {
  background: linear-gradient(135deg, var(--clr-accent), var(--clr-accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}


/* ── 6. XP Progress Bar ──────────────────────────────────── */
.xp-section {
  display: flex;
  flex-direction: column;
  gap: var(--sp-xs);
}

.xp-label-row {
  display: flex;
  justify-content: space-between;
  font-size: var(--fs-xs);
  color: var(--clr-text-muted);
}

#xp-label-title {
  font-weight: 600;
  color: var(--clr-text);
}

.xp-bar-track {
  position: relative;
  height: 10px;
  background: var(--clr-surface-alt);
  border-radius: var(--radius-pill);
  overflow: visible; /* orb can peek out */
  border: 1px solid var(--clr-border);
}

.xp-bar-fill {
  height: 100%;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg, var(--clr-accent), var(--clr-accent-2));
  width: 0%;
  transition: width 0.55s cubic-bezier(0.25, 1, 0.5, 1);
  position: relative;
  z-index: 1;
}

/* Glowing orb that sits at the fill tip */
.xp-bar-orb {
  position: absolute;
  top: 50%;
  left: 0%;
  transform: translate(-50%, -50%);
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: white;
  box-shadow: 0 0 10px 4px var(--clr-accent), 0 0 22px 8px var(--clr-accent-glow);
  transition: left 0.55s cubic-bezier(0.25, 1, 0.5, 1);
  z-index: 2;
  pointer-events: none;
}

/* Hide orb when bar is 0 */
.xp-bar-orb.hide { opacity: 0; }


/* ── 7. Task Input ───────────────────────────────────────── */
.task-input-section { /* no extra style needed – form handles it */ }

.task-form {
  display: flex;
  gap: var(--sp-sm);
}

.task-input {
  flex: 1;
  height: 48px;
  padding: 0 var(--sp-md);
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  color: var(--clr-text);
  font-size: var(--fs-base);
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
}

.task-input::placeholder { color: var(--clr-text-muted); }

.task-input:focus {
  border-color: var(--clr-accent);
  box-shadow: 0 0 0 3px var(--clr-accent-glow);
}

/* ── Shared button base ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border-radius: var(--radius-md);
  font-size: var(--fs-base);
  font-weight: 600;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
}

.btn:active { transform: scale(0.95); }

.btn-add {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  background: var(--clr-accent);
  color: #fff;
  font-size: var(--fs-md);
  border-radius: var(--radius-md);
  box-shadow: 0 4px 14px rgba(124,106,247,0.4);
}

.btn-add:hover {
  background: #8f7fff;
  box-shadow: 0 6px 18px rgba(124,106,247,0.55);
}

.btn-primary {
  padding: var(--sp-sm) var(--sp-xl);
  background: linear-gradient(135deg, var(--clr-accent), var(--clr-accent-2));
  color: #fff;
  font-size: var(--fs-md);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 18px rgba(124,106,247,0.45);
  margin-top: var(--sp-md);
}

.btn-primary:hover { opacity: 0.9; }

.btn-ghost {
  color: var(--clr-text-muted);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: var(--fs-sm);
  font-weight: 500;
}

.btn-ghost:hover {
  background: var(--clr-surface-alt);
  color: var(--clr-text);
}

.btn-sm { font-size: var(--fs-xs); padding: 5px 10px; }


/* ── 8. Task List & Items ────────────────────────────────── */
.task-list-section { display: flex; flex-direction: column; gap: var(--sp-sm); }

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-sm);
  padding: var(--sp-xl) 0;
  color: var(--clr-text-muted);
  font-size: var(--fs-sm);
}

.empty-icon { font-size: 2.5rem; }

.task-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-sm);
}

/* Individual task card */
.task-item {
  display: flex;
  align-items: center;
  gap: var(--sp-md);
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  padding: var(--sp-md);
  transition: border-color var(--transition), background var(--transition),
              transform 0.15s ease, opacity 0.3s ease;
  /* Entry animation */
  animation: slideIn 0.25s ease both;
}

.task-item:hover {
  border-color: var(--clr-accent);
  transform: translateY(-1px);
}

/* Completed state */
.task-item.completed {
  background: var(--clr-success-bg);
  border-color: var(--clr-success);
  opacity: 0.75;
}

.task-item.completed .task-name {
  text-decoration: line-through;
  color: var(--clr-text-muted);
}

/* Custom checkbox */
.task-checkbox {
  appearance: none;
  -webkit-appearance: none;
  width: 22px;
  height: 22px;
  min-width: 22px;
  border: 2px solid var(--clr-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: background var(--transition), border-color var(--transition), transform 0.15s ease;
  background: transparent;
}

.task-checkbox:hover { border-color: var(--clr-accent); }

.task-checkbox:checked {
  background: var(--clr-success);
  border-color: var(--clr-success);
  animation: checkPop 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.5) both;
}

/* Checkmark via pseudo-element */
.task-checkbox:checked::after {
  content: '';
  display: block;
  width: 5px;
  height: 9px;
  border: 2px solid #0f1117;
  border-top: none;
  border-left: none;
  transform: rotate(45deg) translateY(-1px);
}

.task-name {
  flex: 1;
  font-size: var(--fs-base);
  color: var(--clr-text);
  line-height: 1.4;
  word-break: break-word;
}

/* Points badge on each task */
.task-points-badge {
  font-size: var(--fs-xs);
  font-weight: 700;
  padding: 3px 8px;
  border-radius: var(--radius-pill);
  background: var(--clr-surface-alt);
  color: var(--clr-text-muted);
  white-space: nowrap;
  transition: background var(--transition), color var(--transition);
}

.task-item.completed .task-points-badge {
  background: rgba(74,222,128,0.2);
  color: var(--clr-success);
}

/* Delete button (shown on hover) */
.task-delete-btn {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--clr-text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity var(--transition), background var(--transition), color var(--transition);
  flex-shrink: 0;
}

.task-item:hover .task-delete-btn { opacity: 1; }

.task-delete-btn:hover {
  background: rgba(248,113,113,0.15);
  color: var(--clr-danger);
}

/* Floating +5 pts pop that appears on check */
.pts-pop {
  position: fixed;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--clr-success);
  pointer-events: none;
  z-index: 9999;
  animation: ptsFly 1s ease-out forwards;
  text-shadow: 0 0 10px rgba(74,222,128,0.5);
}


/* ── 9. Suggestion Chips ─────────────────────────────────── */
.suggestions-section {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  flex-wrap: wrap;
}

.suggestions-label {
  font-size: var(--fs-xs);
  color: var(--clr-text-muted);
  white-space: nowrap;
}

.suggestion-chips { display: flex; flex-wrap: wrap; gap: 6px; }

.chip {
  padding: 5px 12px;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-pill);
  font-size: var(--fs-xs);
  color: var(--clr-text-muted);
  cursor: pointer;
  background: var(--clr-surface);
  transition: border-color var(--transition), color var(--transition),
              background var(--transition), transform 0.15s ease;
}

.chip:hover {
  border-color: var(--clr-accent);
  color: var(--clr-text);
  background: var(--clr-surface-alt);
  transform: translateY(-1px);
}

.chip.used {
  opacity: 0.4;
  pointer-events: none;
}


/* ── 10. Footer ──────────────────────────────────────────── */
.app-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--sp-md);
  border-top: 1px solid var(--clr-border);
}

.footer-note {
  font-size: var(--fs-xs);
  color: var(--clr-text-muted);
}


/* ── 11. Toast Notification ─────────────────────────────── */
.toast {
  position: fixed;
  bottom: var(--sp-xl);
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--clr-surface);
  border: 1px solid var(--clr-accent);
  border-radius: var(--radius-pill);
  padding: 12px var(--sp-lg);
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--clr-text);
  box-shadow: 0 8px 32px rgba(0,0,0,0.5), var(--shadow-glow);
  z-index: 1000;
  white-space: nowrap;
  transition: opacity 0.35s ease, transform 0.35s ease;
  opacity: 0;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}


/* ── 12. Celebration Overlay ────────────────────────────── */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  padding: var(--sp-md);
  animation: fadeIn 0.3s ease;
}

.overlay.hidden { display: none; }

.overlay-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-accent);
  border-radius: var(--radius-lg);
  padding: var(--sp-xl) var(--sp-lg);
  max-width: 360px;
  width: 100%;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-md);
  box-shadow: 0 0 60px var(--clr-accent-glow);
  position: relative;
  overflow: hidden;
  animation: scaleIn 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.4) both;
}

.overlay-emoji { font-size: 3.5rem; animation: bounce 1s infinite alternate; }

.overlay-card h2 {
  font-size: var(--fs-xl);
  background: linear-gradient(135deg, var(--clr-accent), var(--clr-accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.overlay-card p {
  color: var(--clr-text-muted);
  font-size: var(--fs-sm);
  line-height: 1.6;
}

.cycles-note {
  color: var(--clr-text) !important;
  font-size: var(--fs-base) !important;
  background: var(--clr-surface-alt);
  padding: var(--sp-sm) var(--sp-lg);
  border-radius: var(--radius-pill);
  border: 1px solid var(--clr-border);
  width: 100%;
}

/* Confetti burst container */
.confetti-burst {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}

.confetti-piece {
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  animation: confettiFall var(--dur, 1.5s) var(--delay, 0s) linear forwards;
}


/* ── 13. Animations & Transitions ───────────────────────── */

/* Task card entry */
@keyframes slideIn {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* Checkbox pop */
@keyframes checkPop {
  0%   { transform: scale(0.7); }
  70%  { transform: scale(1.2); }
  100% { transform: scale(1); }
}

/* +5 pts float-up */
@keyframes ptsFly {
  0%   { opacity: 1; transform: translateY(0) scale(1); }
  80%  { opacity: 1; }
  100% { opacity: 0; transform: translateY(-60px) scale(0.9); }
}

/* Overlay fade in */
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* Overlay card scale in */
@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.8); }
  to   { opacity: 1; transform: scale(1); }
}

/* Trophy bounce */
@keyframes bounce {
  from { transform: translateY(0); }
  to   { transform: translateY(-10px); }
}

/* Confetti fall */
@keyframes confettiFall {
  0%   { transform: translateY(-20px) rotate(0deg); opacity: 1; }
  100% { transform: translateY(400px) rotate(720deg); opacity: 0; }
}

/* Level-up bar pulse */
@keyframes barPulse {
  0%, 100% { box-shadow: 0 0 6px 2px var(--clr-accent-glow); }
  50%       { box-shadow: 0 0 20px 8px var(--clr-accent-glow); }
}

.xp-bar-fill.level-up-pulse {
  animation: barPulse 0.6s ease 3;
}

/* Hidden utility */
.hidden { display: none !important; }


/* ── 14. Responsive ─────────────────────────────────────── */
@media (max-width: 480px) {
  .app-wrapper { padding: var(--sp-md) var(--sp-sm) var(--sp-xl); gap: var(--sp-md); }

  .brand-name  { font-size: 1.15rem; }
  .today-date  { font-size: 0.7rem; }

  .stat-value  { font-size: 1.6rem; }

  .task-input  { font-size: 0.88rem; }

  .suggestions-section { flex-direction: column; align-items: flex-start; }

  .app-footer { flex-wrap: wrap; gap: var(--sp-sm); justify-content: center; }

  .toast { font-size: var(--fs-xs); padding: 10px var(--sp-md); white-space: normal; text-align: center; width: 90%; }
}