* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at top, #1b2638, #05070b 70%);
  font-family: Arial, sans-serif;
  color: white;
  display: flex;
  justify-content: center;
  min-height: 100vh;
}

.app {
  width: 100%;
  max-width: 520px;
  padding: 10px;
}

/* ===== TITLE ===== */
.title {
  text-align: center;
  font-size: 24px;
  font-weight: 700;
  margin: 4px 0 6px 0;
  letter-spacing: 1px;
  font-family: 'Poppins', sans-serif;
  color: #eaeef5;
  text-shadow: 0 0 8px rgba(255,255,255,0.15);
}

.title .accent {
  background: linear-gradient(
    90deg,
    #ff3b3b,
    #ffd21a,
    #06a83f,
    #075be8,
    #ff8500,
    #f7358c,
    #a8f000
  );

  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ===== TOP BAR ===== */
.top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
  gap: 5px;
}

#timer,
#mistakes {
  width: 62px;
  text-align: center;
  font-weight: bold;
  font-size: 14px;
}

/* ===== DIFFICULTY ===== */
.difficulty-row {
  display: flex;
  gap: 5px;
  flex: 1;
  margin: 0 5px;
}

.diff {
  flex: 1;
  padding: 6px;
  border-radius: 8px;
  border: none;
  background: #1d2633;
  color: white;
  font-size: 13px;
  cursor: pointer;
  transition: 0.15s;
}

.diff:active {
  transform: scale(0.96);
}

.diff.active {
  background: white;
  color: black;
  font-weight: bold;
}

/* ===== BOARD ===== */
.board {
  display: grid;
  grid-template-columns: repeat(9,1fr);
  aspect-ratio: 1;
  border: 3px solid white;
  border-radius: 8px;
  overflow: hidden;
}

.cell {
  position: relative;
  display:flex;
  justify-content:center;
  align-items:center;
  border-right:1px solid rgba(255,255,255,0.18);
  border-bottom:1px solid rgba(255,255,255,0.18);
  transition: background 0.12s;
}

.cell:nth-child(9n) {
  border-right: none;
}

.cell:nth-child(n+73) {
  border-bottom: none;
}

/* ===== 3x3 GRID ===== */
.cell:nth-child(3n) {
  border-right: 3px solid white;
}

.cell:nth-child(n+19):nth-child(-n+27),
.cell:nth-child(n+46):nth-child(-n+54) {
  border-bottom: 3px solid white;
}

/* ===== STATES ===== */
.cell.selected {
  outline: 3px solid white;
  outline-offset: -3px;
  z-index: 2;
}

.highlight {
  background: rgba(255,255,255,0.08);
}

.same {
  box-shadow: inset 0 0 0 2px white;
}

.cell.flash {
  animation: flash 0.3s;
}

@keyframes flash {
  0% {
    background: rgba(255,255,255,0.85);
  }
  100% {
    background: transparent;
  }
}

/* ===== MAIN COLOR DOT ===== */
.color-dot {
  width: 70%;
  height: 70%;
  border-radius: 50%;
  box-shadow:
    inset 0 2px 5px rgba(255,255,255,0.15),
    inset 0 -3px 6px rgba(0,0,0,0.35);
}

/* ===== NOTES ===== */
.note-grid {
  width: 82%;
  height: 82%;
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 2px;
}

.note-slot {
  display: flex;
  justify-content: center;
  align-items: center;
}

.note-dot {
  width: 68%;
  height: 68%;
  border-radius: 50%;
  opacity: 0.9;
}

/* ===== BOTTOM ===== */
.bottom-panel {
  margin-top: 8px;
}

/* ===== COLOR PAD ===== */
.color-pad {
  display:grid;
  grid-template-columns:repeat(9,1fr);
  gap:5px;
}

.color-btn {
  position: relative;
  border-radius: 50%;
  aspect-ratio: 1;
  border: 2px solid white;
  cursor: pointer;
  transition: 0.12s;
}

.color-btn:active {
  transform: scale(0.92);
}

.color-btn.selected-color {
  outline: 3px solid white;
  outline-offset: 2px;
}

.color-btn.disabled {
  opacity: 0.28;
  pointer-events: none;
}

/* count badge */
.count {
  position:absolute;
  bottom:-5px;
  right:-3px;
  font-size:10px;
  background:black;
  padding:2px 4px;
  border-radius:4px;
  line-height: 1;
}

/* ===== CONTROLS ===== */
.controls {
  display:flex;
  gap:8px;
  margin-top:10px;
}

.controls button {
  flex:1;
  padding:10px;
  border-radius:10px;
  border:none;
  background:#1d2633;
  color:white;
  font-size: 13px;
  cursor:pointer;
  transition:0.15s;
}

.controls button:active {
  transform: scale(0.96);
}

#noteBtn.active {
  background: white;
  color: black;
  font-weight: bold;
}

/* ===== OVERLAY ===== */
.overlay {
  position:fixed;
  inset:0;
  background:rgba(0,0,0,0.82);
  display:flex;
  justify-content:center;
  align-items:center;
  z-index:100;
}

.overlay.hidden {
  display:none;
}

.overlay-box {
  background:#111827;
  padding:24px;
  border-radius:14px;
  text-align:center;
  min-width:260px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.overlay-box h2 {
  margin-top: 0;
  white-space: pre-line;
}

.overlay-box button {
  margin-top: 12px;
  padding: 10px 18px;
  border: none;
  border-radius: 10px;
  background: white;
  color: black;
  font-weight: bold;
  cursor: pointer;
}

/* ===== COLORS ===== */
.c1 { background:#ff1616; }
.c2 { background:#ffd21a; }
.c3 { background:#06a83f; }
.c4 { background:#075be8; }
.c5 { background:#ff8500; }
.c6 { background:#f5f5f5; }
.c7 { background:#9b9b9b; }
.c8 { background:#f7358c; }
.c9 { background:#a8f000; }

/* ===== MOBILE ===== */
@media (max-width: 480px) {

  .title {
    font-size: 22px;
  }

  .diff {
    font-size: 12px;
    padding: 5px;
  }

  .controls button {
    font-size: 12px;
    padding: 9px;
  }

  #timer,
  #mistakes {
    font-size: 12px;
    width: 55px;
  }
}

/* ===== MOBILE FIX ===== */

.nav-links{
  text-align:center;
  margin:10px 0 14px;
}

.nav-links a{
  color:#6fb1ff;
  text-decoration:none;
  margin:0 10px;
  font-size:15px;
  font-weight:500;
}

.footer-links{
  text-align:center;
  margin-top:18px;
}

.footer-links a{
  color:#6fb1ff;
  text-decoration:none;
}