body {
  margin: 0;
  padding: 0;
  font-family: 'Noto Serif SC', serif;
  background: linear-gradient(to bottom, #fdf6e3, #f5e4cc); /* 默认淡雅 */
  text-align: center;
  min-height: 100vh;
  transition: background 0.5s ease;
}

body.theme-dark {
  background: #e8efe3;
  color: #333;
}

#goBoard {
  background-color: #fdf6e3;
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.2);
  margin-top: 30px; /* ✅ 避免偏移过近上边 */
  border-radius: 8px;
}


  canvas {
    background: #f0d9b5;
    border: 2px solid #8b5a2b;
    margin-top: 20px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.2);
  }
  
  h1 {
    margin-top: 30px;
    font-size: 32px;
    color: #333;
  }
  
  #status {
    margin-top: 10px;
    font-size: 18px;
    color: #555;
  }
  
  #hostControls {
    margin-top: 20px;
  }
  
  /* ✅ 水墨风菜单核心设计 */
  #startMenu {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 32px;
    border-radius: 16px;
    width: 320px;
    z-index: 10;
    display: flex;
    flex-direction: column;
    gap: 16px;
    align-items: center;
  
    background: linear-gradient(145deg, #f6f4ee, #d6cfc2);


    box-shadow:
      0 8px 24px rgba(0, 0, 0, 0.15),
      inset 0 1px 0 rgba(255, 255, 255, 0.2);
  
    border: 1px solid #ccc;
    font-family: 'Noto Serif SC', serif;
  }
  
  
  
  
  
  
  
  
  /* ✅ 淡入动画 */
  @keyframes fadeIn {
    from {
      opacity: 0;
      transform: translate(-50%, -60%) scale(0.96);
    }
    to {
      opacity: 1;
      transform: translate(-50%, -50%) scale(1);
    }
  }
  
  /* 标题 */
  #startMenu h2 {
    font-size: 22px;
    font-weight: bold;
    color: #111;
    margin-bottom: 8px;
  }
  
  /* 标签 */
  #startMenu label {
    font-size: 14px;
    color: #333;
  }
  
  /* 输入框和选择框 */
  #startMenu select,
  #startMenu input {
    padding: 10px;
    font-size: 16px;
    width: 100%;
    border: 1px solid #aaa;
    border-radius: 10px;
    outline: none;
    background: #fff;
    transition: all 0.2s;
  }
  
  #startMenu select:focus,
  #startMenu input:focus {
    border-color: #4caf50;
    box-shadow: 0 0 5px rgba(76, 175, 80, 0.3);
  }
  
  /* 按钮设计 */
  #startMenu button {
    width: 100%;
    padding: 12px 20px;
    font-size: 16px;
    font-weight: bold;
    color: white;
    background: linear-gradient(to right, #111, #333);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    backdrop-filter: blur(2px);
    box-shadow: inset 0 0 0 0 transparent;
    transition: all 0.3s ease;
  


}
  
  #startMenu button:hover {
    background: linear-gradient(to right, #444, #111);
    box-shadow: inset 0 0 5px rgba(255, 255, 255, 0.05);
  }
  
  /* 装饰符号 ● ○ */
  .black-btn::before {
    content: "● ";
    color: #4caf50;
  }
  .white-btn::before {
    content: "○ ";
    color: #2196f3;
  }
  
  /* 控制按钮风格 */
  .black-btn {
    background-color: #000;
    color: white;
  }
  .black-btn:hover {
    background-color: #333;
  }
  
  .white-btn {
    background-color: white;
    color: black;
    border: 1px solid #aaa;
  }
  .white-btn:hover {
    background-color: #f0f0f0;
  }
  
  .controls {
    margin-top: 20px;
  }
  
  #info {
    margin-top: 20px;
    font-size: 20px;
    color: #333;
    white-space: pre-line;
    font-weight: bold;
  }
  
  @keyframes inkFloat {
    0% {
      background-position: 0% 0%, 20% 30%, 80% 70%, 0% 0%;
    }
    50% {
      background-position: 10% 10%, 22% 32%, 78% 68%, 10% 10%;
    }
    100% {
      background-position: 0% 0%, 20% 30%, 80% 70%, 0% 0%;
    }
  }
  
  #gameInfoBar {
    text-align: center;
    font-size: 16px;
    padding: 8px;
    background-color: #f9f9f9;
    border-bottom: 1px solid #ccc;
  }
  .chess-choice {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin: 10px 0;
  }
  
  .chess-option {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 3px solid transparent;
    cursor: pointer;
    transition: 0.3s;
  }
  
  .chess-option.black {
    background-color: black;
  }
  
  .chess-option.white {
    background-color: white;
    border: 2px solid #ccc;
  }
  
  .chess-option.selected {
    border: 3px solid gold;
    box-shadow: 0 0 10px gold;
  }