*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --bg:        #111827;
  --surface:   #1e2937;
  --surface-2: #293548;
  --border:    #3a4f66;
  --text:      #f1f5f9;
  --text-muted:#94a3b8;
  --primary:   #0ea5e9;
  --danger:    #ef4444;
  --accent:    #fb923c;
  --radius:    12px;
  --font:      'Poppins', system-ui, sans-serif;
  --shadow:    0 24px 64px rgba(0,0,0,0.55);
  --t:         0.2s ease;
}

body.light-mode {
  --bg:        #f0f4f8;
  --surface:   #ffffff;
  --surface-2: #e8edf3;
  --border:    #cbd5e1;
  --text:      #1e293b;
  --text-muted:#64748b;
  --shadow:    0 24px 64px rgba(0,0,0,0.1);
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  padding: 48px 20px 80px;
  display: flex;
  justify-content: center;
  transition: background var(--t), color var(--t);
}

/* ── Container ─────────────────────────────── */
.todo-container {
  width: 100%;
  max-width: 680px;
  background: var(--surface);
  border-radius: 20px;
  padding: 36px 32px;
  box-shadow: var(--shadow);
  height: fit-content;
  transition: background var(--t), box-shadow var(--t);
}

/* ── Header ────────────────────────────────── */
.header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 28px;
}

h1 {
  font-size: 1.9rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-sub {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.theme-btn {
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  color: var(--text-muted);
  width: 40px;
  height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--t);
  flex-shrink: 0;
}
.theme-btn:hover { color: var(--primary); border-color: var(--primary); }

/* ── Add task grid ─────────────────────────── */
.add-task {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 18px;
}

/* Icon-wrapped inputs */
.input-icon-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.input-icon-wrap > svg {
  position: absolute;
  left: 13px;
  color: var(--text-muted);
  pointer-events: none;
  flex-shrink: 0;
}

.input-icon-wrap input,
.input-icon-wrap select {
  width: 100%;
  padding: 12px 14px 12px 36px;
}

/* Task text input spans full row */
.input-icon-wrap:first-child {
  grid-column: 1 / -1;
}

#taskInput,
#dueDate,
#prioritySelect,
#categorySelect,
.search-bar {
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.93rem;
  font-family: var(--font);
  transition: border-color var(--t), background var(--t);
  -webkit-appearance: none;
  appearance: none;
}

#taskInput:focus,
#dueDate:focus,
#prioritySelect:focus,
#categorySelect:focus,
.search-bar:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--surface);
}

/* Color scheme for date picker in dark mode */
#dueDate::-webkit-calendar-picker-indicator {
  filter: invert(0.6);
  cursor: pointer;
}

body.light-mode #dueDate::-webkit-calendar-picker-indicator {
  filter: none;
}

/* Select chevron */
.select-wrap::after {
  content: '';
  position: absolute;
  right: 12px;
  width: 0; height: 0;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid var(--text-muted);
  pointer-events: none;
}

#addBtn {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--t);
}
#addBtn:hover {
  background: #0284c7;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(14,165,233,0.3);
}

/* ── Search ────────────────────────────────── */
.search-wrap {
  position: relative;
  display: flex;
  align-items: center;
  margin-bottom: 20px;
}

.search-wrap > svg {
  position: absolute;
  left: 13px;
  color: var(--text-muted);
  pointer-events: none;
}

.search-bar {
  width: 100%;
  padding: 11px 14px 11px 36px;
}

/* ── Filter groups ─────────────────────────── */
.filter-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.filter-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  min-width: 58px;
}

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

.filters button {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 14px;
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: 999px;
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--t);
}

.filters button:hover,
.filters button.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

.filters button.active .p-dot,
.filters button:hover .p-dot {
  border-color: white;
}

/* ── Priority dot ──────────────────────────── */
.p-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
  display: inline-block;
}
.p-dot.high   { background: #ef4444; }
.p-dot.medium { background: #f59e0b; }
.p-dot.low    { background: #22c55e; }

/* ── Task list ─────────────────────────────── */
#taskList {
  list-style: none;
  margin: 20px 0 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

#taskList li {
  background: var(--surface-2);
  padding: 14px 16px;
  border-radius: var(--radius);
  display: flex;
  align-items: flex-start;
  gap: 12px;
  border: 1.5px solid var(--border);
  transition: all var(--t);
  cursor: grab;
}

#taskList li:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 14px rgba(14,165,233,0.1);
}

#taskList li.completed .task-text {
  text-decoration: line-through;
  color: var(--text-muted);
}
#taskList li.completed { opacity: 0.65; }

#taskList li.overdue {
  border-left: 3px solid var(--danger);
}

#taskList li.dragging { opacity: 0.35; cursor: grabbing; }
#taskList li.drag-over {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(251,146,60,0.2);
}

#taskList input[type=checkbox] {
  width: 17px;
  height: 17px;
  accent-color: var(--primary);
  cursor: pointer;
  flex-shrink: 0;
  margin-top: 3px;
}

.task-body { flex: 1; min-width: 0; }

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

.task-text {
  font-size: 0.95rem;
  font-weight: 500;
  word-break: break-word;
  line-height: 1.4;
}

.task-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 6px;
}

.due-date {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.78rem;
  color: var(--primary);
}
.due-date.overdue-label { color: var(--danger); font-weight: 600; }
.due-date svg { flex-shrink: 0; }

.cat-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.73rem;
  font-weight: 500;
  text-transform: capitalize;
  padding: 2px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text-muted);
  background: var(--surface);
}

.delete-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all var(--t);
}
.delete-btn:hover { background: rgba(239,68,68,0.12); color: var(--danger); }

/* Empty state */
.empty-state {
  text-align: center;
  padding: 36px 20px;
  color: var(--text-muted);
  font-size: 0.95rem;
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  cursor: default;
  list-style: none;
}

/* ── Stats ─────────────────────────────────── */
.stats {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
  padding-top: 16px;
  margin-top: 20px;
}

#clearCompleted {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: 1.5px solid var(--danger);
  color: var(--danger);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--t);
}
#clearCompleted:hover { background: var(--danger); color: white; }

/* ── Shake animation ───────────────────────── */
@keyframes shake {
  0%,100% { transform: translateX(0); }
  25%      { transform: translateX(-6px); }
  75%      { transform: translateX(6px); }
}
.shake { animation: shake 0.35s ease; }

/* ── Responsive ────────────────────────────── */
@media (max-width: 520px) {
  .todo-container { padding: 24px 16px; }
  .add-task { grid-template-columns: 1fr; }
  .input-icon-wrap:first-child { grid-column: 1; }
  #addBtn { grid-column: 1; }
  .filter-group { flex-direction: column; align-items: flex-start; }
}