/* ABOUTME: Styles for the plutimikation multiplication practice app. */
/* ABOUTME: Black/white/grey design with color only for validation feedback. */

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

html, body {
  overflow-x: hidden;
}

body {
  font-family: 'Nimbus Mono PS', 'Courier New', monospace;
  background: #f5f5f5;
  color: #111;
  display: flex;
  justify-content: center;
  min-height: 100vh;
  padding: 0;
  -webkit-user-select: none;
  user-select: none;
}

@media (min-width: 420px) {
  body { padding: 8px; }
}

.card {
  width: 100%;
  max-width: 400px;
  background: #fff;
  border: none;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

@media (min-width: 420px) {
  .card { border: 2px solid #111; min-height: auto; }
}

/* Header */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 16px;
  border-bottom: 2px solid #111;
}

.header h1 {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 1px;
}

.settings-btn {
  background: none;
  border: 2px solid #111;
  font-size: 20px;
  cursor: pointer;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: inherit;
}

.settings-btn:hover {
  background: #eee;
}

/* Task display */
.task-area {
  padding: 16px 12px;
  overflow-y: auto;
  flex: 1;
}

@media (min-width: 420px) {
  .task-area { flex: 0 1 auto; }
}

.factors {
  text-align: right;
  padding-right: 4px;
  margin-bottom: 4px;
  font-size: 22px;
  font-weight: 700;
  line-height: 1.6;
  white-space: nowrap;
}

.separator {
  border: none;
  border-top: 2px solid #111;
  margin: 6px 0;
}

/* Grid */
.grid-row {
  display: flex;
  justify-content: flex-end;
  margin: 3px 0;
  gap: 2px;
}

.grid-row.carry-row {
  margin: 1px 0;
}

.grid-row.row-error .cell {
  background: #ffe0d0;
  border-color: #c44;
}

.grid-row.row-correct .cell {
  background: #d4f5d4;
  border-color: #4a4;
}

.cell {
  width: 32px;
  height: 36px;
  border: 2px solid #999;
  text-align: center;
  font-family: 'Nimbus Mono PS', 'Courier New', monospace;
  font-size: 18px;
  font-weight: 600;
  line-height: 32px;
  cursor: pointer;
  background: #fff;
  color: #111;
  caret-color: transparent;
  outline: none;
  padding: 0;
}

.cell.carry-cell {
  width: 32px;
  height: 22px;
  font-size: 12px;
  font-weight: 400;
  line-height: 18px;
  border: 1px solid #bbb;
  color: #666;
}

.cell:focus, .cell.active {
  border-color: #111;
  border-width: 3px;
  background: #f8f8e8;
}

.cell.carry-cell:focus, .cell.carry-cell.active {
  border-width: 2px;
}

.cell.revealed {
  background: #e0e0e0;
  color: #666;
  border-color: #aaa;
}

/* Numpad */
.numpad {
  padding: 8px 12px 8px;
  border-top: 2px solid #111;
}

.numpad-row {
  display: flex;
  gap: 4px;
  margin-bottom: 4px;
}

.numpad-btn {
  flex: 1;
  height: 44px;
  border: 2px solid #111;
  background: #fff;
  font-family: 'Nimbus Mono PS', 'Courier New', monospace;
  font-size: 20px;
  font-weight: 600;
  cursor: pointer;
}

.numpad-btn:hover {
  background: #eee;
}

.numpad-btn:active {
  background: #ddd;
}

/* Action buttons */
.actions {
  padding: 4px 12px 12px;
}

.action-btn {
  display: block;
  width: 100%;
  padding: 12px;
  border: 2px solid #111;
  background: #fff;
  font-family: 'Nimbus Mono PS', 'Courier New', monospace;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
  margin-bottom: 4px;
}

.action-btn:hover {
  background: #eee;
}

.action-btn:active {
  background: #ddd;
}

/* Overlays */
.overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.4);
  z-index: 100;
  justify-content: center;
  align-items: flex-start;
  padding-top: 60px;
}

.overlay.open {
  display: flex;
}

.overlay-panel {
  background: #fff;
  border: 2px solid #111;
  width: 90%;
  max-width: 360px;
  padding: 20px;
}

.overlay-panel h2 {
  font-size: 16px;
  margin-bottom: 16px;
  border-bottom: 2px solid #111;
  padding-bottom: 8px;
}

.radio-group label {
  display: block;
  padding: 8px 4px;
  cursor: pointer;
  font-size: 14px;
}

.radio-group input[type="radio"] {
  margin-right: 8px;
  transform: scale(1.2);
}

.overlay-close {
  display: block;
  width: 100%;
  padding: 10px;
  margin-top: 16px;
  border: 2px solid #111;
  background: #fff;
  font-family: 'Nimbus Mono PS', 'Courier New', monospace;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
}

.overlay-close:hover {
  background: #eee;
}

/* Stats */
.stat-line {
  font-size: 14px;
  padding: 4px 0;
}

.stat-section {
  margin-top: 12px;
  padding-top: 8px;
  border-top: 1px solid #ccc;
}

.stat-section .stat-line {
  padding-left: 12px;
}

/* Confetti */
.confetti-container {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  z-index: 200;
  overflow: hidden;
}

.confetti-piece {
  position: absolute;
  width: 8px;
  height: 8px;
  top: -10px;
  animation: confetti-fall 2.5s ease-out forwards;
}

@keyframes confetti-fall {
  0% {
    transform: translateY(0) rotate(0deg);
    opacity: 1;
  }
  100% {
    transform: translateY(100vh) rotate(720deg);
    opacity: 0;
  }
}