:root{
  --bg:#fff;
  --fg:#8a8a8a;
  --txt: #000;
  --chk:#000;
  --now:#e0ffff;
  --blk:#000;
  --bar:#fff;
  --wht:#fcfcfc;
  --muted:#777;
  --line:#0003;
  --shadow:0 8px 24px rgba(0,0,0,0.08);
  --radius:16px;
  --blue:#00d0ff;
  --red:#ff2f00;
  --anim-fast:.18s;
  --anim-mid:.24s;
  --bg-row-odd: #dddddd;
  --bg-row-even: #f4f4f4;
  --accent: #2a9c73;
}

.dark {
  --bg: #000;
  --bar: #1e1e1e;
  --fg: #343434;
  --txt: #fff;
  --now: #1e1e1e;
  --chk:#a3a3a3;
  --muted: #aaa;
  --line: #fff3;
  --blk:#fff;
  --wht:#0b0b0b;
  --bg-row-odd: #131313;
  --bg-row-even: #0a0a0a;
}

*{box-sizing:border-box;}

html, body {
  min-height: 100dvh;
  margin: 0;
  padding: 0;
  background: var(--wht);
  color: var(--blk);
  font: 15px/1.4 "Comic Relief", system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  letter-spacing: 0.2px;
  -webkit-text-size-adjust: 100%;
  transition: background-color 0.4s ease, color 0.4s ease;
}

body {
  overflow-x: hidden;
}

body::-webkit-scrollbar, html::-webkit-scrollbar {
  -webkit-appearance: none;
  width: 6px;
  height: 6px;
}
body::-webkit-scrollbar-thumb, html::-webkit-scrollbar-thumb {
  background: var(--line);
  border-radius: 3px;
}

main {
  flex: 1;
  padding: 20px;
  max-width: 600px;
  margin: 0 auto;
  width: 100%;
}

/* ── App Header ── */
.app-header {
  position: sticky;
  top: 0;
  z-index: 5;
  background: var(--bar);
  border-bottom: 1px solid var(--line);
  padding: calc(14px + env(safe-area-inset-top, 0px)) 20px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: background-color 0.4s ease, border-color 0.4s ease;
}

.header-title {
  font-size: 22px;
  font-weight: bold;
  color: var(--txt);
}

.header-actions {
  display: flex;
  gap: 8px;
  align-items: center;
}

.header-icon-btn {
  background: transparent;
  border: 1px solid var(--fg);
  color: var(--txt);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  display: grid;
  place-items: center;
  outline: none;
  transition: background var(--anim-fast) ease, transform var(--anim-fast) ease;
}

.header-icon-btn:active {
  transform: scale(0.9);
}

/* Completed icon flash animation */
@keyframes icon-flash-green {
  0%   { color: var(--txt); transform: scale(1); }
  35%  { color: #00e676; transform: scale(1.45); background: rgba(0,230,118,0.15); }
  65%  { color: #00e676; transform: scale(0.95); background: rgba(0,230,118,0.05); }
  100% { color: var(--txt); transform: scale(1); background: transparent; }
}

.header-icon-btn--flash {
  animation: icon-flash-green 0.8s cubic-bezier(0.34, 1.56, 0.64, 1);
}


/* ── FABs ── */
.fab-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  z-index: 9999;
  transition: transform 0.35s cubic-bezier(0.22,1,0.36,1), opacity 0.35s ease;
}

.fab-container.fab-hide {
  transform: translate(60px, 60px) rotate(45deg);
  opacity: 0;
  pointer-events: none;
}

.fab-btn {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  border: none;
  padding: 0;
  margin: 0;
  appearance: none;
  -webkit-appearance: none;
  box-shadow: var(--shadow);
  cursor: pointer;
  pointer-events: auto;
  display: grid;
  place-items: center;
  transition: transform var(--anim-fast) ease;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}

.fab-btn:active {
  transform: scale(0.9);
}

.fab-add {
  background: var(--txt);
  color: var(--bg);
  font-size: 32px;
  font-weight: 300;
}


/* ── Modal ── */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  z-index: 9999;
  padding: 20px;
  padding-top: 25vh;
  transition: opacity var(--anim-fast) ease;
  overscroll-behavior: none;
  touch-action: none;
}

.modal-overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.modal-card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 20px 40px rgba(0,0,0,0.2);
  transform: translateY(0);
  transition: transform var(--anim-fast) ease;
}

.modal-overlay.hidden .modal-card {
  transform: translateY(20px);
}

.modal-title {
  margin: 0 0 16px 0;
  color: var(--txt);
  font-size: 18px;
}

.modal-input {
  width: 100%;
  padding: 12px 16px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--wht);
  color: var(--txt);
  font: inherit;
  outline: none;
  margin-bottom: 24px;
}

.modal-input:focus {
  border-color: var(--blue);
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

.modal-btn {
  padding: 10px 20px;
  border-radius: 99px;
  font: inherit;
  font-weight: bold;
  cursor: pointer;
  border: none;
}

.cancel-btn {
  background: transparent;
  color: var(--fg);
}

.confirm-btn {
  background: var(--txt);
  color: var(--bg);
}


/* ── Task List ── */
.task-list {
  list-style: none;
  padding: 0;
  margin: 0;
  position: relative;
}

/* Zebra Task Items */
.topic-item {
  position: relative;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 20px;
  margin-bottom: 12px;
  border-radius: var(--radius);
  background: var(--bg-row-even);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  transition: opacity var(--anim-fast) ease, box-shadow var(--anim-fast) ease, background-color 0.5s ease;
  cursor: grab;
  touch-action: pan-y;
  overflow: hidden;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}

.topic-item.is-odd {
  background: var(--bg-row-odd);
}
.topic-item.is-even {
  background: var(--bg-row-even);
}

.topic-item:last-child {
  margin-bottom: 0;
}





/* ── Lifted dragging item ── */
.topic-item.drag-active {
  position: fixed;
  z-index: 9000;
  pointer-events: none;
  box-shadow: 0 20px 60px rgba(0,0,0,0.18);
  transform: scale(1.03);
  opacity: 1;
  cursor: grabbing;
  transition: none;
}




/* ── Checkbox ── */
.cb-hit {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  margin: -10px 0 -10px -10px;
  border-radius: 50%;
  cursor: pointer;
  flex-shrink: 0;
}

.topic-item__checkbox {
  appearance: none;
  width: 22px;
  height: 22px;
  border: 2px solid var(--fg);
  border-radius: 6px;
  background: transparent;
  cursor: pointer;
  position: relative;
  transition: background var(--anim-fast) ease, border-color var(--anim-fast) ease;
}

.topic-item__checkbox:checked {
  background: var(--accent);
  border-color: var(--accent);
}

.topic-item__checkbox:checked::after {
  content: '';
  position: absolute;
  left: 6px;
  top: 2px;
  width: 6px;
  height: 12px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

.task-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  pointer-events: none;
}

.task-title {
  font-size: 16px;
  font-weight: 500;
  color: var(--txt);
  transition: color var(--anim-fast) ease;
}

.task-time {
  font-size: 12px;
  color: var(--muted);
  margin-top: 4px;
  height: 16px;
}

.topic-item--complete .task-title {
  text-decoration: line-through;
  color: var(--muted);
}


/* ── Entry Animation ── */
@keyframes card-slide-up {
  from { opacity: 0; transform: translateY(22px) scale(0.97); }
}

.card--animate-in {
  animation: card-slide-up 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

/* ── Checkbox celebration pop ── */
@keyframes checkbox-pop {
  0% { transform: scale(1); }
  25% { transform: scale(1.4); }
  45% { transform: scale(0.85); }
  65% { transform: scale(1.18); }
  85% { transform: scale(0.98); }
  100% { transform: scale(1.1); }
}

.topic-item--celebrate .topic-item__checkbox {
  animation: checkbox-pop 0.55s cubic-bezier(0.22, 1, 0.36, 1) 0.05s;
}

@keyframes topic-celebrate {
  0% { box-shadow: 0 0 0 0 rgba(42, 156, 115, 0); }
  20% { box-shadow: 0 0 0 6px rgba(42, 156, 115, 0.35); transform: scale(1.02); }
  40% { box-shadow: 0 0 0 12px rgba(42, 156, 115, 0.12); }
  60% { box-shadow: 0 0 0 16px rgba(42, 156, 115, 0); transform: scale(1); }
  100% { box-shadow: none; }
}

.topic-item--celebrate {
  animation: topic-celebrate 0.85s ease-out;
}

.topic-item__flash {
  position: absolute;
  inset: 0;
  background: white;
  border-radius: var(--radius);
  opacity: 0;
  pointer-events: none;
  animation: celebrate-flash 0.65s ease-out;
}

@keyframes celebrate-flash {
  0% { opacity: 0.35; }
  100% { opacity: 0; }
}

.topic-item__ripple {
  position: absolute;
  width: 100px;
  height: 100px;
  background: rgba(42, 156, 115, 0.4);
  border-radius: 50%;
  transform: translate(-50%, -50%) scale(0);
  pointer-events: none;
  animation: ripple-expand 0.55s ease-out;
}

@keyframes ripple-expand {
  0% { transform: translate(-50%, -50%) scale(0); opacity: 0.5; }
  100% { transform: translate(-50%, -50%) scale(2.5); opacity: 0; }
}

/* ── Confetti ── */
.confetti-layer {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  pointer-events: none;
  z-index: 9999;
}
.confetti-particle {
  position: absolute;
  transform-origin: center;
}


/* ── Completed Tasks Panel ── */
.completed-panel {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  width: min(380px, 85vw);
  background: var(--bg);
  border-left: 1px solid var(--line);
  box-shadow: -8px 0 30px rgba(0,0,0,0.12);
  z-index: 500;
  display: flex;
  flex-direction: column;
  transform: translateX(0);
  transition: transform 0.35s cubic-bezier(0.22,1,0.36,1), opacity 0.25s ease;
}

.completed-panel.hidden {
  transform: translateX(100%);
  pointer-events: none;
}

.completed-panel__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 20px;
  padding-top: calc(env(safe-area-inset-top) + 18px);
  border-bottom: 1px solid var(--line);
}

.completed-panel__title {
  margin: 0;
  font-size: 18px;
  color: var(--txt);
}

.completed-panel__close {
  background: transparent;
  border: none;
  color: var(--txt);
  cursor: pointer;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  transition: background var(--anim-fast) ease;
}

.completed-panel__close:hover {
  background: var(--line);
}

.completed-task-list {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
}

.completed-task-list .topic-item {
  cursor: default;
  touch-action: auto;
}

.completed-empty {
  padding: 40px 20px;
  text-align: center;
  color: var(--muted);
  font-size: 14px;
}

/* Scrim behind completed panel */
.completed-scrim {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.35);
  z-index: 499;
  transition: opacity 0.3s ease;
}
.completed-scrim.hidden {
  opacity: 0;
  pointer-events: none;
}

/* ── Drag Placeholder ── */
.drag-placeholder {
  position: relative;
  display: flex;
  justify-content: flex-end;
  align-items: center;
  padding-right: 24px;
  border-radius: var(--radius);
}

.drag-placeholder::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(to right, #ff3b30 0%, rgba(255, 59, 48, 0.4) 25%, transparent 50%);
  opacity: var(--red-progress, 0);
  z-index: 1;
  border-radius: var(--radius);
  pointer-events: none;
  transition: opacity 0.15s ease-out;
}

.drag-placeholder__content {
  color: var(--txt);
  opacity: 0;
  transform: translateX(-35px) rotate(-180deg) scale(0.4);
  pointer-events: none;
  position: relative;
  z-index: 2;
}

.drag-placeholder__content.delete-active {
  opacity: 1;
  transform: translateX(0px) rotate(0deg) scale(1.15);
}