html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  overflow: hidden;
  font-family: system-ui;
  background: #000;
}

#ocean {
  width: 100vw;
  height: 100vh;
  position: relative;
  cursor: pointer;
  overflow: hidden;
  background: linear-gradient(#002244, #00111c);
}

/* INTRO SCREEN */
#intro {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0, 17, 28, 0.6);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  color: #aeeaff;
  text-align: center;
  z-index: 9999;
  transition: opacity 1s ease;
}

#intro.hidden {
  opacity: 0;
  pointer-events: none;
}

#title {
  font-size: 4em;
  margin: 0;
  letter-spacing: 2px;
  text-shadow: 0 0 20px rgba(100, 200, 255, 0.8);
}

#start-text {
  font-size: 1.5em;
  opacity: 0.8;
  margin: 1em 0;
}

/* Mode area */
#mode-select {
  display: flex;
  gap: 2em;
  justify-content: center;
}

.mode-option {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.shape-preview {
  width: 80px;
  height: 50px;
  margin-bottom: 0.5em;
}

.classic-shape {
  border-radius: 50%;
  background: linear-gradient(135deg, #7be2ff, #2b8fff);
}

.geometric-shape {
  clip-path: polygon(0 50%, 35% 0, 100% 25%, 100% 75%, 35% 100%);
  background: linear-gradient(135deg, #6ae2ff, #0bb);
}

.blend-shape {
  background: linear-gradient(135deg, #7be2ff, #2b8fff);
  animation: blendSwitch 4s infinite;
}

@keyframes blendSwitch {
  0%, 45% {
    clip-path: ellipse(50% 40% at 50% 50%);
    border-radius: 50%;
  }
  55%, 100% {
    clip-path: polygon(0 50%, 35% 0, 100% 25%, 100% 75%, 35% 100%);
    border-radius: 0;
  }
}

#mode-select button {
  margin: 0.3em;
  padding: 0.8em 1.5em;
  font-size: 1.1em;
  color: #fff;
  background: rgba(100, 200, 255, 0.15);
  border: 1px solid #aeeaff;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s;
}

#mode-select button:hover {
  background: rgba(100, 200, 255, 0.5);
  box-shadow: 0 0 10px rgba(100, 200, 255, 0.4);
}

/* FISH FLOAT */
@keyframes float {
  0%   { transform: translateY(0) translateX(0); }
  50%  { transform: translateY(-10px) translateX(3px); }
  100% { transform: translateY(0) translateX(0); }
}

/* GAME MENU */
#game-menu {
  position: absolute;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(0, 17, 28, 0.7);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 10000;
  transition: opacity 0.3s ease;
  opacity: 0;
  pointer-events: none;
}

#game-menu:not(.hidden) {
  opacity: 1;
  pointer-events: auto;
}

#game-menu-window {
  background: rgba(0, 30, 50, 0.9);
  border: 1px solid #aeeaff;
  border-radius: 12px;
  box-shadow: 0 0 20px rgba(100, 200, 255, 0.5);
  padding: 2em;
  color: #aeeaff;
  min-width: 300px;
  text-align: center;
}

#game-menu-window h2 {
  margin-top: 0;
  margin-bottom: 1em;
}

.menu-row {
  display: flex;
  justify-content: space-between;
  margin: 1em 0;
  align-items: center;
}

#game-menu button,
#game-menu input[type="range"] {
  cursor: pointer;
  font-size: 1.1em;
  background: rgba(100, 200, 255, 0.15);
  border: 1px solid #aeeaff;
  border-radius: 8px;
  padding: 0.4em 1em;
  color: #fff;
  transition: all 0.3s;
}

#game-menu button:hover {
  background: rgba(100, 200, 255, 0.5);
  box-shadow: 0 0 10px rgba(100, 200, 255, 0.4);
}