:root {
  --bg-0: #f8f6ef;
  --bg-1: #e7ece9;
  --card: #ffffffd9;
  --text: #182225;
  --muted: #4f5f62;
  --accent: #d85a3f;
  --accent-2: #264c72;
  --correct: #2d8f4e;
  --present: #d9a11f;
  --absent: #86989a;
  --tile: #f4f6f7;
  --border: #cad6d8;
  --shadow: 0 10px 30px rgba(20, 36, 39, 0.15);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Space Grotesk", "Avenir Next", "Trebuchet MS", sans-serif;
  color: var(--text);
  background: linear-gradient(160deg, var(--bg-0), var(--bg-1));
  position: relative;
}

.backdrop {
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 10% 20%, rgba(216, 90, 63, 0.18), transparent 40%),
    radial-gradient(circle at 80% 0%, rgba(38, 76, 114, 0.2), transparent 35%),
    radial-gradient(circle at 90% 75%, rgba(45, 143, 78, 0.14), transparent 28%);
  pointer-events: none;
}

.app-shell {
  position: relative;
  max-width: 980px;
  margin: 0 auto;
  padding: 1.2rem;
  display: grid;
  gap: 1rem;
  animation: rise 0.35s ease-out;
}

@keyframes rise {
  from {
    transform: translateY(10px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: end;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 1rem 1.2rem;
}

.eyebrow {
  margin: 0;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.75rem;
}

h1,
h2,
h3 {
  margin: 0;
}

h1 {
  font-size: clamp(1.6rem, 2.7vw, 2.2rem);
  letter-spacing: 0.02em;
}

.controls,
.status-strip,
.board-wrap,
.actions,
.keyboard-wrap,
.simulation,
.answer {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 1rem;
}

.controls {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.8rem;
  align-items: end;
}

label {
  display: grid;
  gap: 0.3rem;
  color: var(--muted);
  font-weight: 600;
  font-size: 0.92rem;
}

select,
button {
  font: inherit;
  border-radius: 11px;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  padding: 0.56rem 0.72rem;
}

button {
  cursor: pointer;
  font-weight: 700;
  border-color: transparent;
  background: var(--accent);
  color: #fff;
  transition: transform 0.14s ease, opacity 0.14s ease;
}

button:hover:not(:disabled) {
  transform: translateY(-1px);
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.ghost-btn {
  background: #fff;
  border: 1px solid var(--border);
  color: var(--accent-2);
}

.status-strip {
  min-height: 3rem;
  display: flex;
  align-items: center;
}

.status-strip p {
  margin: 0;
  font-weight: 600;
}

.board {
  display: grid;
  gap: 0.45rem;
}

.board-row {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.45rem;
}

.cell,
.current-token {
  min-height: 3.1rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--tile);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "IBM Plex Mono", "Menlo", monospace;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  font-size: 0.72rem;
  text-align: center;
  padding: 0.1rem 0.2rem;
  line-height: 1.12;
}

.cell.pending {
  border-style: dashed;
  background: #ffffff;
}

.cell.editable {
  cursor: pointer;
  border-style: dashed;
}

.cell.editable:hover {
  border-color: var(--accent-2);
}

.cell.correct,
.key-btn.correct {
  background: var(--correct);
  color: #fff;
  border-color: transparent;
}

.cell.present,
.key-btn.present {
  background: var(--present);
  color: #fff;
  border-color: transparent;
}

.cell.absent,
.key-btn.absent {
  background: var(--absent);
  color: #fff;
  border-color: transparent;
}

.actions {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.6rem;
}

.keyboard-wrap h2,
.simulation h2 {
  font-size: 1.08rem;
  margin-bottom: 0.6rem;
}

.keyboard {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(74px, 1fr));
  gap: 0.45rem;
}

.key-btn {
  width: 100%;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  font-family: "IBM Plex Mono", "Menlo", monospace;
  font-size: 0.82rem;
  padding: 0.5rem 0.4rem;
}

.mode-guide {
  margin-top: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.65rem 0.75rem;
  background: #f8fbfb;
}

.mode-guide h3 {
  margin: 0 0 0.35rem;
  font-size: 0.9rem;
}

.mode-guide ul {
  margin: 0;
  padding-left: 1rem;
  color: var(--muted);
  font-size: 0.84rem;
}

.mode-guide li + li {
  margin-top: 0.22rem;
}

.sim-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}

.sim-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.8rem;
}

.sim-circuit {
  margin-top: 0.75rem;
}

.sim-circuit h3 {
  margin: 0 0 0.4rem;
}

pre {
  margin: 0;
  padding: 0.75rem;
  border-radius: 10px;
  background: #f8fbfb;
  border: 1px solid var(--border);
  color: #1f2f33;
  min-height: 5.8rem;
  overflow-x: auto;
  font-size: 0.84rem;
}

.equivalent-message {
  margin: 0 0 0.7rem;
  color: var(--correct);
  font-weight: 700;
}

.hidden {
  display: none;
}

.compat-hidden {
  display: none !important;
}

.answer p {
  margin: 0;
  font-weight: 700;
}

.stats-modal {
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
  width: min(680px, 92vw);
  padding: 1rem;
}

.stats-modal::backdrop {
  background: rgba(10, 20, 23, 0.35);
}

.stats-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.7rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.6rem;
  margin-bottom: 0.8rem;
}

.stat-card {
  border-radius: 10px;
  border: 1px solid var(--border);
  padding: 0.6rem;
  background: #fafdfd;
}

.stat-label {
  color: var(--muted);
  font-size: 0.76rem;
  text-transform: uppercase;
}

.stat-value {
  font-weight: 800;
  font-size: 1.3rem;
}

.dist-row {
  display: grid;
  grid-template-columns: 22px 1fr 32px;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 0.35rem;
}

.dist-bar {
  height: 0.85rem;
  border-radius: 999px;
  background: linear-gradient(90deg, #2d8f4e, #5fb47a);
}

@media (max-width: 780px) {
  .controls,
  .actions,
  .sim-grid {
    grid-template-columns: 1fr;
  }

  .keyboard {
    grid-template-columns: repeat(auto-fit, minmax(64px, 1fr));
  }

  .board-row {
    gap: 0.35rem;
  }

  .cell,
  .current-token {
    min-height: 2.7rem;
    font-size: 0.82rem;
  }

  .stats-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}