:root {
  --color-red: #e53935;
  --color-red-light: #ff6f60;
  --color-green: #43a047;
  --color-green-light: #76d275;
  --color-yellow: #fdd835;
  --color-yellow-light: #ffff6b;
  --color-blue: #1e88e5;
  --color-blue-light: #6ab7ff;
  --bg-dark: #0f172a;
  --bg-panel: #1e293b;
  --text-primary: #f1f5f9;
  --text-muted: #94a3b8;
  --accent: #38bdf8;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
  --radius: 16px;
}

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

body {
  font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
}

.game-container {
  width: 100%;
  max-width: 480px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.game-header {
  text-align: center;
}

.game-title {
  font-size: 2.4rem;
  font-weight: 800;
  letter-spacing: 2px;
  background: linear-gradient(90deg, var(--accent), #a78bfa);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.title-reg {
  font-size: 1.2rem;
  vertical-align: super;
  -webkit-text-fill-color: var(--text-muted);
}

.game-subtitle {
  color: var(--text-muted);
  font-size: 0.9rem;
  letter-spacing: 1px;
  margin-top: 4px;
}

.game-board {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  background: var(--bg-panel);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 10px;
  padding: 10px;
}

.pad {
  border-radius: 12px;
  cursor: pointer;
  transition:
    transform 0.1s ease,
    filter 0.1s ease,
    box-shadow 0.1s ease;
  position: relative;
  overflow: hidden;
}

.pad:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.pad:active {
  transform: scale(0.97);
}

.pad-red {
  background: var(--color-red);
  box-shadow: inset 0 -6px 0 rgba(0, 0, 0, 0.2);
}

.pad-green {
  background: var(--color-green);
  box-shadow: inset 0 -6px 0 rgba(0, 0, 0, 0.2);
}

.pad-yellow {
  background: var(--color-yellow);
  box-shadow: inset 0 -6px 0 rgba(0, 0, 0, 0.2);
}

.pad-blue {
  background: var(--color-blue);
  box-shadow: inset 0 -6px 0 rgba(0, 0, 0, 0.2);
}

.pad.active {
  transform: scale(0.95);
  filter: brightness(1.6);
  box-shadow: 0 0 30px rgba(255, 255, 255, 0.4);
}

.pad-red.active {
  background: var(--color-red-light);
}

.pad-green.active {
  background: var(--color-green-light);
}

.pad-yellow.active {
  background: var(--color-yellow-light);
}

.pad-blue.active {
  background: var(--color-blue-light);
}

.pad.disabled {
  pointer-events: none;
  opacity: 0.6;
}

.center-console {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 38%;
  aspect-ratio: 1;
  background: var(--bg-panel);
  border-radius: 50%;
  box-shadow:
    0 0 0 8px var(--bg-panel),
    0 8px 24px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  z-index: 2;
  text-align: center;
  padding: 8px;
}

.level-display {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 1px;
}

.status-display {
  font-size: 0.7rem;
  color: var(--text-muted);
  line-height: 1.3;
  max-width: 90%;
}

.status-display.error {
  color: #f87171;
}

.status-display.success {
  color: #4ade80;
}

.controls {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

.btn {
  border: none;
  border-radius: 10px;
  padding: 12px 20px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition:
    transform 0.1s ease,
    box-shadow 0.1s ease,
    background 0.2s ease;
  letter-spacing: 0.5px;
}

.btn:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

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

.btn-start {
  background: linear-gradient(135deg, #22c55e, #16a34a);
  color: #fff;
  box-shadow: 0 4px 12px rgba(34, 197, 94, 0.3);
}

.btn-start:hover {
  box-shadow: 0 6px 16px rgba(34, 197, 94, 0.4);
}

.btn-start.started {
  background: linear-gradient(135deg, #ef4444, #dc2626);
  box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
}

.btn-strict {
  background: var(--bg-panel);
  color: var(--text-primary);
  border: 1px solid #334155;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.btn-strict.active {
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.btn-sound {
  background: var(--bg-panel);
  color: var(--text-primary);
  border: 1px solid #334155;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
}

.btn-sound .icon {
  width: 20px;
  height: 20px;
}

.btn-sound.muted {
  color: var(--text-muted);
  opacity: 0.6;
}

.game-footer {
  color: var(--text-muted);
  font-size: 0.8rem;
}

.game-footer a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}

.game-footer a:hover {
  text-decoration: underline;
}

@media (max-width: 400px) {
  .game-container {
    padding: 16px;
  }

  .game-title {
    font-size: 1.8rem;
  }

  .btn {
    padding: 10px 14px;
    font-size: 0.8rem;
  }

  .level-display {
    font-size: 0.9rem;
  }

  .status-display {
    font-size: 0.6rem;
  }
}