:root {
  color-scheme: dark;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: radial-gradient(circle at top, #0d1738 0%, #02040b 50%, #000 100%);
  color: #f4f7ff;
}

body {
  position: relative;
}

canvas {
  display: block;
}

#hud {
  position: fixed;
  top: 18px;
  left: 18px;
  z-index: 20;
  padding: 14px 18px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 16px;
  background: rgba(5, 12, 28, 0.75);
  backdrop-filter: blur(10px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

.title {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.28rem;
  color: #72f6ff;
  text-transform: uppercase;
}

#score {
  margin-top: 6px;
  font-size: 1.05rem;
  font-weight: 600;
}

.tips {
  margin-top: 4px;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.74);
}

.overlay {
  position: fixed;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  background: rgba(3, 6, 16, 0.78);
  backdrop-filter: blur(8px);
}

.overlay.hidden {
  display: none;
}

.panel {
  width: min(92vw, 560px);
  padding: 28px;
  border-radius: 24px;
  background: linear-gradient(145deg, rgba(13, 21, 42, 0.98), rgba(8, 13, 29, 0.96));
  border: 1px solid rgba(114, 246, 255, 0.18);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
}

h1 {
  margin: 0 0 10px;
  font-size: 2rem;
  color: #ff7f7f;
}

#finalScore {
  margin: 0 0 18px;
  font-size: 1.1rem;
  color: #dce7ff;
}

label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: #9fe9ff;
}

input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(6, 10, 24, 0.85);
  color: #fff;
  font-size: 1rem;
  outline: none;
}

input:focus {
  border-color: #72f6ff;
  box-shadow: 0 0 0 2px rgba(114, 246, 255, 0.2);
}

.buttons {
  display: flex;
  gap: 12px;
  margin-top: 16px;
}

button {
  flex: 1;
  padding: 12px 16px;
  border: none;
  border-radius: 999px;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

button:hover {
  transform: translateY(-1px);
}

#submitBtn {
  background: linear-gradient(135deg, #73f6ff, #00a7ff);
  color: #00121c;
}

#playAgainBtn {
  background: linear-gradient(135deg, #ff8c4d, #ff4c65);
  color: #fff;
}

.leaderboard-card {
  margin-top: 20px;
  padding: 16px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.leaderboard-card h2 {
  margin: 0 0 12px;
  font-size: 1.08rem;
  color: #ffd36f;
}

.leaderboard-table {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.leaderboard-row {
  display: grid;
  grid-template-columns: 44px 1fr 72px;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.05);
}

.rank {
  font-weight: 800;
  color: #72f6ff;
}

.name {
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.score {
  text-align: right;
  font-weight: 700;
  color: #ffd36f;
}

.empty {
  padding: 10px 0;
  color: rgba(255, 255, 255, 0.7);
}

@media (max-width: 640px) {
  .panel {
    padding: 20px;
  }

  .buttons {
    flex-direction: column;
  }
}