html, body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  background-color: #121212;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
}

#gameCanvas {
  /* Size is controlled in JS; keep element intrinsic size minimal */
  display: block;
}

#settings-panel {
  background-color: rgba(0, 0, 0, 0.5);
  color: #fff;
  padding: 12px 16px;
  border-radius: 8px;
  font-family: sans-serif;
  margin: 16px 0 12px 0;
}
#settings-panel .row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}
#settings-panel label {
  min-width: 120px;
}
#settings-panel input[type="range"] {
  width: 220px;
}
#settings-panel button {
  width: 100%;
  padding: 10px 12px;
  background: #1976d2;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}
#settings-panel button:hover {
  background: #0d47a1;
}

/* Return to menu hint (drawn on canvas textually; class reserved if needed) */
.return-hint {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  color: #fff;
}

/* Custom Level Editor */
#custom-level-editor {
  background: rgba(0, 0, 0, 0.5);
  color: #fff;
  padding: 12px 16px;
  border-radius: 8px;
  margin: 12px 0 0 0;
  border: 1px solid #444;
}
#custom-level-editor h3 {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
#help-button {
  padding: 4px 8px;
  border-radius: 50%;
  border: 1px solid #666;
  background: #2e7d32;
  color: #fff;
  cursor: pointer;
}
#custom-level-editor .row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}
#custom-level-editor input[type="text"] {
  flex: 1;
  padding: 8px;
  border-radius: 6px;
  border: 1px solid #444;
  background: #1f1f1f;
  color: #fff;
}
.error-message {
  color: #ff5252;
  margin-top: 8px;
}
#level-select-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #121212;
  color: white;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

#level-buttons-container {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  justify-content: center;
  padding: 12px 20px 8px 20px;
}

#level-buttons-container button {
  padding: 15px 30px;
  font-size: 1.2em;
  background-color: #333;
  color: white;
  border: 2px solid #555;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
}

#level-buttons-container button:hover {
  background-color: #4CAF50;
  border-color: #81C784;
}

.hidden {
  display: none !important;
}

/* Splash screen */
#splash-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: #fff;
  background: radial-gradient(circle at center, #1e1e1e 0%, #0d0d0d 70%);
  z-index: 200;
}
#splash-screen h1 {
  font-size: 18vw;
  margin: 0 0 10px 0;
}
#splash-screen p {
  font-size: 18px;
  opacity: 0.8;
}

/* In-game UI overlay */
#game-ui-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  display: block;
  padding: 10px 14px;
  z-index: 120;
  pointer-events: none;
}
#back-to-menu-button {
  pointer-events: auto;
  padding: 8px 12px;
  background: #424242;
  color: #fff;
  border: 1px solid #616161;
  border-radius: 6px;
  cursor: pointer;
  position: absolute;
  top: 10px;
  left: 14px;
}
#back-to-menu-button:hover {
  background: #616161;
}
#timer {
  pointer-events: none;
  color: #fff;
  font-family: monospace;
  font-size: 18px;
  margin-right: 10px;
  position: absolute;
  top: 10px;
  right: 14px;
}
#level-select-screen .title-header {
  margin-bottom: 12px;
}
#level-select-screen .main-title {
  display: block;
  text-align: center;
  font-size: 72px;
  font-weight: 700;
}
#level-select-screen .sub-title {
  display: block;
  text-align: center;
  font-size: 20px;
  color: #bbb;
}

.designer-credit-menu {
  position: fixed;
  right: 10px;
  bottom: 10px;
  color: rgba(255,255,255,0.7);
  font-size: 12px;
  font-family: sans-serif;
}

#designer-credit {
  position: fixed;
  right: 10px;
  bottom: 10px;
  color: rgba(255,255,255,0.7);
  font-size: 12px;
  font-family: sans-serif;
}

/* Help Modal */
#help-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 300;
}
#help-modal .modal-content {
  background: #fff;
  color: #222;
  border-radius: 10px;
  padding: 20px 24px;
  max-width: 720px;
  width: 90%;
  position: relative;
}
#help-modal .close-button {
  position: absolute;
  top: 8px;
  right: 10px;
  background: transparent;
  border: none;
  font-size: 24px;
  cursor: pointer;
}
#help-modal h2 { margin-top: 0; }
#help-modal h3 { margin-bottom: 6px; }
#help-modal p, #help-modal li { line-height: 1.6; }
#help-modal code { background: #f5f5f5; padding: 2px 4px; border-radius: 4px; }

/* Highlight selected level button */
#level-buttons-container button.selected {
  background-color: #4CAF50;
  border-color: #81C784;
  color: white;
  font-weight: bold;
  box-shadow: 0 0 10px rgba(129, 199, 132, 0.7);
}

/* Game over screen */
#game-over-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 150;
}
#game-over-screen .message-box {
  background: #1e1e1e;
  color: #fff;
  padding: 24px 28px;
  border-radius: 10px;
  text-align: center;
  min-width: 320px;
}
#game-over-screen .buttons {
  margin-top: 16px;
  display: flex;
  gap: 10px;
  justify-content: center;
}
#game-over-screen button {
  padding: 10px 14px;
  background: #2e7d32;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}
#game-over-screen button#return-to-menu-button {
  background: #1976d2;
}
#game-over-screen button:hover {
  filter: brightness(1.1);
}

#settings-panel .row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

#settings-panel label {
  min-width: 100px;
}

#settings-panel input[type="range"] {
  width: 160px;
}

#settings-panel button {
  width: 100%;
  margin-top: 8px;
  padding: 8px 10px;
  background: #2e7d32;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

#settings-panel button:hover {
  background: #1b5e20;
}