/* Global Theme Variables */
:root {
  --bg: #0f172a; /* slate-900 */
  --surface: #111827; /* gray-900 */
  --card: #1f2937; /* gray-800 */
  --text: #e5e7eb; /* gray-200 */
  --text-muted: #9ca3af; /* gray-400 */
  --primary: #22d3ee; /* cyan-400 */
  --primary-contrast: #0b1020;
  --accent: #a78bfa; /* violet-400 */
  --danger: #f43f5e; /* rose-500 */
  --success: #22c55e; /* green-500 */
  --warning: #f59e0b; /* amber-500 */
  --border: #334155; /* slate-700 */
  --shadow: 0 8px 24px rgba(0,0,0,0.35);
  --radius: 14px;
  --radius-sm: 10px;
  --radius-xs: 8px;
}

/* Light Theme */
:root.light {
  --bg: #f8fafc; /* slate-50 */
  --surface: #ffffff;
  --card: #f1f5f9; /* slate-100 */
  --text: #0f172a; /* slate-900 */
  --text-muted: #475569; /* slate-600 */
  --primary: #2563eb; /* blue-600 */
  --primary-contrast: #ffffff;
  --accent: #7c3aed; /* violet-600 */
  --danger: #dc2626;
  --success: #16a34a;
  --warning: #d97706;
  --border: #e2e8f0; /* slate-200 */
}

/* Base Reset */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: radial-gradient(1200px 600px at 20% 0%, #0b1226 0%, var(--bg) 60%), var(--bg);
  letter-spacing: 0.2px;
}

/* App Shell */
.app {
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr auto;
}
.header {
  position: sticky;
  top: 0;
  backdrop-filter: saturate(1.2) blur(10px);
  background: linear-gradient(180deg, rgba(2,6,23,0.6), rgba(2,6,23,0.3));
  border-bottom: 1px solid var(--border);
  z-index: 10;
}
.header-inner {
  max-width: 1040px;
  margin: 0 auto;
  padding: 16px 20px;
  display: flex;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}
.brand-logo {
  width: 36px; height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  box-shadow: 0 6px 18px rgba(34, 211, 238, 0.25);
}
.brand-title {
  font-weight: 700;
  letter-spacing: 0.4px;
}
.brand-sub {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.main {
  max-width: 1040px;
  margin: 28px auto;
  padding: 0 20px 28px;
}

/* Card */
.card {
  background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.00)), var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 18px 10px;
  border-bottom: 1px dashed var(--border);
}
.card-title {
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 10px;
}
.card-body { padding: 18px; }

/* Controls */
.controls { display: flex; gap: 12px; align-items: center; }
.input {
  flex: 1;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  outline: none;
  transition: border .15s ease, box-shadow .15s ease, transform .05s ease;
}
.input::placeholder { color: var(--text-muted); }
.input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.18);
  transform: translateY(-1px);
}
.input.editing {
  background: linear-gradient(180deg, rgba(34,211,238,0.15), rgba(34,211,238,0.08));
  border-color: var(--primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  cursor: pointer;
  background: var(--surface);
  color: var(--text);
  transition: transform .06s ease, box-shadow .15s ease, background .15s ease, border-color .15s ease;
}
.btn:active { transform: translateY(1px); }
.btn:hover { border-color: var(--primary); }

.btn-primary {
  background: linear-gradient(180deg, rgba(34,211,238,0.18), rgba(34,211,238,0.08));
  border-color: rgba(34,211,238,0.35);
  color: var(--text);
}
.btn-danger {
  background: linear-gradient(180deg, rgba(244,63,94,0.18), rgba(244,63,94,0.08));
  border-color: rgba(244,63,94,0.35);
  color: var(--danger);
}
.btn-danger:hover {
  background: linear-gradient(180deg, rgba(244,63,94,0.3), rgba(244,63,94,0.15));
  border-color: var(--danger);
  box-shadow: 0 0 8px rgba(244,63,94,0.3);
}

.btn-warning {
  background: linear-gradient(180deg, rgba(245,158,11,0.18), rgba(245,158,11,0.08));
  border-color: rgba(245,158,11,0.35);
  color: var(--warning);
}
.btn-warning:hover {
  background: linear-gradient(180deg, rgba(245,158,11,0.3), rgba(245,158,11,0.15));
  border-color: var(--warning);
  box-shadow: 0 0 8px rgba(245,158,11,0.3);
}

.btn-info {
  background: linear-gradient(180deg, rgba(34,211,238,0.18), rgba(34,211,238,0.08));
  border-color: rgba(34,211,238,0.35);
  color: var(--primary);
}
.btn-info:hover {
  background: linear-gradient(180deg, rgba(34,211,238,0.3), rgba(34,211,238,0.15));
  border-color: var(--primary);
}

.btn-success {
  background: linear-gradient(180deg, rgba(34,197,94,0.18), rgba(34,197,94,0.08));
  border-color: rgba(34,197,94,0.35);
  color: var(--success);
}
.btn-success:hover {
  background: linear-gradient(180deg, rgba(34,197,94,0.3), rgba(34,197,94,0.15));
  border-color: var(--success);
  box-shadow: 0 0 8px rgba(34,197,94,0.3);
}

/* Task List */
.list {
  display: grid;
  gap: 12px;
}
.item {
  display: grid;
  grid-template-columns: 24px 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  transition: all .2s ease;
}
.item:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(34, 211, 238, 0.15);
}
.checkbox {
  width: 18px; height: 18px;
  accent-color: var(--primary);
}
.item-title {
  font-weight: 500;
}
.item-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
}
.item-actions { display: flex; gap: 8px; }

/* Table styles */
table {
  width: 100%;
  border-collapse: collapse;
  table-layout: fixed;
}
table thead th {
  background: linear-gradient(180deg, rgba(34,211,238,0.1), transparent);
  padding: 12px;
  text-align: left;
  font-weight: 600;
  border-bottom: 2px solid var(--primary);
  color: var(--primary);
}
table tbody tr {
  border-bottom: 1px solid var(--border);
  transition: all .15s ease;
}
table tbody tr:hover {
  background: rgba(34,211,238,0.05);
}
table td, table th {
  padding: 12px;
}
table th:nth-child(1),
table td:nth-child(1) {
  width: 48px;
}
table th:nth-child(2),
table td:nth-child(2) {
  width: 180px;
}
table th:nth-child(4),
table td:nth-child(4) {
  width: 140px;
}
table th:nth-child(5),
table td:nth-child(5),
table th:nth-child(6),
table td:nth-child(6) {
  width: 80px;
}
.truncate {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
table .text-decoration-line-through {
  opacity: 0.6;
  background: rgba(34,211,238,0.08);
}
table .text-decoration-line-through td {
  text-decoration: line-through;
  color: var(--text-muted);
}
table .text-decoration-line-through .btn {
  opacity: 0.7;
}

/* Footer */
.footer {
  border-top: 1px solid var(--border);
  padding: 18px 20px;
  color: var(--text-muted);
}
.footer-inner { max-width: 1040px; margin: 0 auto; }

/* Theme Toggle */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.switch {
  position: relative;
  width: 48px; height: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 28px;
}
.switch-thumb {
  position: absolute;
  top: 50%; left: 3px;
  transform: translateY(-50%);
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 2px 10px rgba(34, 211, 238, 0.35);
  transition: left .15s ease;
}
:root.light .switch-thumb { left: 23px; }

/* Utilities */
.icon { width: 18px; height: 18px; display: inline-block; }
.separator { height: 1px; background: var(--border); margin: 12px 0; }
.grid-2 { display: grid; grid-template-columns: 1fr auto; gap: 12px; }

/* Animations */
@media (prefers-reduced-motion: no-preference) {
  .card, .item { transition: transform .08s ease, box-shadow .2s ease; }
  .item:hover { transform: translateY(-1px); box-shadow: 0 6px 16px rgba(0,0,0,0.25); }
}