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

:root {
  --bg:           #0d0f14;
  --surface:      rgba(255,255,255,0.04);
  --surface-hover:rgba(255,255,255,0.07);
  --border:       rgba(255,255,255,0.08);
  --border-focus: rgba(139,92,246,0.6);
  --accent:       #8b5cf6;
  --accent-2:     #a78bfa;
  --accent-glow:  rgba(139,92,246,0.35);
  --done-color:   #34d399;
  --text-primary: #f1f5f9;
  --text-secondary:#94a3b8;
  --text-muted:   #475569;
  --danger:       #f87171;
  --radius-sm:    8px;
  --radius-md:    14px;
  --radius-lg:    20px;
  --transition:   0.22s cubic-bezier(0.4,0,0.2,1);
  font-size: 16px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  display: flex;
  justify-content: center;
  padding: 48px 16px 80px;
}

/* ─── Animated orbs (background) ──────────────────────── */
.bg-orbs {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.18;
  animation: drift 18s ease-in-out infinite;
}
.orb-1 {
  width: 520px; height: 520px;
  background: radial-gradient(circle, #7c3aed, transparent);
  top: -140px; left: -120px;
  animation-duration: 20s;
}
.orb-2 {
  width: 380px; height: 380px;
  background: radial-gradient(circle, #06b6d4, transparent);
  bottom: 80px; right: -100px;
  animation-duration: 16s;
  animation-delay: -6s;
}
.orb-3 {
  width: 280px; height: 280px;
  background: radial-gradient(circle, #f59e0b, transparent);
  top: 50%; left: 55%;
  animation-duration: 24s;
  animation-delay: -12s;
}
@keyframes drift {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33%       { transform: translate(30px, -40px) scale(1.05); }
  66%       { transform: translate(-20px, 20px) scale(0.96); }
}

/* ─── Container ────────────────────────────────────────── */
.container {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 620px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* ─── Header ───────────────────────────────────────────── */
.app-header { text-align: center; margin-bottom: 4px; }

.logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 6px 16px;
  border-radius: 999px;
  backdrop-filter: blur(12px);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
}
.logo-icon { color: var(--accent); font-size: 1rem; }
.logo-text  { color: var(--text-primary); }

.app-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, #f1f5f9 0%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.1;
}
.app-subtitle {
  margin-top: 8px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 400;
}

/* ─── Stats bar ─────────────────────────────────────────── */
.stats-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(16px);
  overflow: hidden;
}
.stat-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 16px 12px;
  gap: 2px;
}
.stat-number {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  transition: var(--transition);
}
.stat-label {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--border);
}

/* ─── Progress bar ──────────────────────────────────────── */
.progress-wrap {
  height: 4px;
  background: var(--surface);
  border-radius: 999px;
  overflow: hidden;
  border: 1px solid var(--border);
}
.progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--done-color));
  border-radius: 999px;
  transition: width 0.5s cubic-bezier(0.4,0,0.2,1);
  box-shadow: 0 0 10px rgba(139,92,246,0.5);
}

/* ─── Input form ────────────────────────────────────────── */
.input-form { width: 100%; }

.input-wrap {
  display: flex;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(16px);
  padding: 6px 6px 6px 18px;
  gap: 10px;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.input-wrap:focus-within {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.input-icon {
  font-size: 1.3rem;
  color: var(--accent);
  font-weight: 300;
  line-height: 1;
  flex-shrink: 0;
}

.todo-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-family: inherit;
  font-size: 0.95rem;
  color: var(--text-primary);
  caret-color: var(--accent);
}
.todo-input::placeholder { color: var(--text-muted); }

.add-btn {
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  padding: 10px 22px;
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  flex-shrink: 0;
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
  box-shadow: 0 4px 14px rgba(109,40,217,0.4);
}
.add-btn:hover  { opacity: 0.9; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(109,40,217,0.5); }
.add-btn:active { transform: translateY(0); }

/* ─── Filter tabs ───────────────────────────────────────── */
.filter-tabs {
  display: flex;
  gap: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 6px;
  backdrop-filter: blur(16px);
}
.tab {
  flex: 1;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 500;
  padding: 9px 0;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.tab:hover { background: var(--surface-hover); color: var(--text-primary); }
.tab.active {
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  color: #fff;
  box-shadow: 0 2px 12px var(--accent-glow);
}

/* ─── Todo list ─────────────────────────────────────────── */
.todo-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* ─── Todo item ─────────────────────────────────────────── */
.todo-item {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 16px 18px;
  backdrop-filter: blur(16px);
  transition: border-color var(--transition), background var(--transition), transform var(--transition);
  animation: slideIn 0.28s cubic-bezier(0.4,0,0.2,1);
  position: relative;
  overflow: hidden;
}
.todo-item::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 3px;
  background: var(--accent);
  opacity: 0;
  transition: opacity var(--transition);
  border-radius: 0 3px 3px 0;
}
.todo-item:hover { background: var(--surface-hover); transform: translateY(-1px); border-color: rgba(255,255,255,0.12); }
.todo-item:hover::before { opacity: 1; }
.todo-item.completed { border-color: rgba(52,211,153,0.15); }
.todo-item.completed::before { background: var(--done-color); opacity: 0.6; }

@keyframes slideIn {
  from { opacity: 0; transform: translateY(-10px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeOut {
  to { opacity: 0; transform: translateX(20px) scale(0.96); }
}
.todo-item.removing { animation: fadeOut 0.22s forwards; }

/* Checkbox */
.todo-checkbox {
  width: 22px; height: 22px;
  border-radius: 50%;
  border: 2px solid var(--border);
  background: transparent;
  cursor: pointer;
  flex-shrink: 0;
  display: grid;
  place-items: center;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
  position: relative;
}
.todo-checkbox:hover { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-glow); }
.todo-checkbox.checked {
  background: var(--done-color);
  border-color: var(--done-color);
  box-shadow: 0 0 10px rgba(52,211,153,0.4);
}
.todo-checkbox.checked::after {
  content: '';
  width: 6px; height: 10px;
  border: 2.5px solid #0d0f14;
  border-top: none; border-left: none;
  transform: rotate(45deg) translate(-1px, -1px);
  display: block;
}

/* Text */
.todo-text {
  flex: 1;
  font-size: 0.95rem;
  font-weight: 400;
  color: var(--text-primary);
  transition: color var(--transition);
  line-height: 1.4;
  word-break: break-word;
}
.todo-item.completed .todo-text {
  text-decoration: line-through;
  color: var(--text-muted);
}

/* Timestamp */
.todo-time {
  font-size: 0.72rem;
  color: var(--text-muted);
  flex-shrink: 0;
  white-space: nowrap;
}

/* Delete button */
.delete-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px 6px;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  line-height: 1;
  flex-shrink: 0;
  transition: color var(--transition), background var(--transition);
  opacity: 0;
  transition: opacity var(--transition), color var(--transition), background var(--transition);
}
.todo-item:hover .delete-btn { opacity: 1; }
.delete-btn:hover { color: var(--danger); background: rgba(248,113,113,0.1); }

/* ─── Empty state ───────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 52px 24px;
  color: var(--text-muted);
}
.empty-icon { font-size: 3rem; margin-bottom: 16px; }
.empty-title { font-size: 1.1rem; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; }
.empty-sub   { font-size: 0.85rem; }

/* ─── Actions row ───────────────────────────────────────── */
.actions-row { display: flex; justify-content: flex-end; }
.clear-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.8rem;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
}
.clear-btn:hover { border-color: var(--danger); color: var(--danger); background: rgba(248,113,113,0.06); }

/* ─── Responsive ────────────────────────────────────────── */
@media (max-width: 480px) {
  .add-btn   { padding: 10px 14px; font-size: 0.8rem; }
  .todo-time { display: none; }
}