:root {
            --box-size       : 90px;
            --center-size    : 90px;
            --char-size      : 30px;
            --pinyin-size    : 15px;
            --box-space      : 135px;
            --face-z         : 45px;
            --color-center: rgba(0, 0, 0, 0.9);
            --color-root: rgba(173, 129, 205, 0.95);
            --color-radical: rgba(172, 67, 172, 0.95);
            --color-pinyin: rgba(111, 30, 99, 0.95);
            --color2-root: rgba(152, 189, 83, 0.95);
            --color2-radical: rgba(39, 102, 43, 0.95);
            --color2-pinyin: rgba(2, 54, 6, 0.95);
            --color3-root: rgba(30, 120, 180, 0.95);
            --color3-radical: rgba(255, 20, 20, 0.95);
            --color3-pinyin: rgba(0, 141, 54, 0.95);
            --color-mono: rgba(5, 101, 140, 0.95);
            --text-color     : #ffffff;
        }
        * { margin:0; padding:0; box-sizing:border-box; }
        html, body { height: 100%; }
        body { min-height:100vh; display:flex; flex-direction:column; background:#f0f0f0; }

        #debugPanel {
            position: fixed; top:120px; left:80px;
            background:rgba(0,0,0,0.8); color:#fff;
            padding:8px 12px; border-radius:6px;
            font-size:14px; z-index:99999;
            font-family: monospace;
        }

        header nav ul {
            display:flex; align-items:center; list-style:none;
            background:#fff; height:60px; padding:0 20px;
            box-shadow:0 2px 8px rgba(0,0,0,0.05);
        }
        header nav li { margin:0 12px; }
        header nav a { text-decoration:none; color:#333; font-size:16px; }
        header nav a:hover { color:#4e8cff; }

        .main-container {
            display:flex; width:100%; height:calc(100vh - 120px);
            gap:10px; padding:10px;
        }
/* ————————————————————————————————
   左右侧边栏 统一基础样式
———————————————————————————————— */
.left-menu, .right-menu {
    width: 5%;
    height: 100%;
    background: #96775c;
    border-radius: 14px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.05);
    padding: 10px;
    box-sizing: border-box;
}

/* —— 左侧偏旁：两列布局 —— */
.left-menu {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4px;
    align-content: start;
}

/* —— 右侧拼音：单列布局 —— */
.right-menu {
    margin-left: auto;
    display: flex;
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 4px;
}

/* ————————————————————————————————
   左右菜单标题：完全统一
———————————————————————————————— */
.menu-title {
    grid-column: 1 / -1;
    width: 100%;
    font-size: 14px !important;
    font-weight: bold !important;
    text-align: center;
    margin-bottom: 8px;
    padding-bottom: 4px;
    border-bottom: 1px solid #ddd;
}

/* ————————————————————————————————
   按钮统一样式
———————————————————————————————— */
.radical-item,
.pinyin-item {
    width: 100%;
    padding: 4px 2px;
    background: #f5f7fa;
    border-radius: 4px;
    text-align: center;
    cursor: pointer;
    font-size: 12px;
    font-weight: bold;
    transition: 0.2s;
}

/* 点击高亮效果 */
.radical-item:hover, .pinyin-item:hover,
.radical-item.active, .pinyin-item.active {
    background: #4e8cff;
    color: #fff;
}

/* 中间区域自动占满剩余空间 —— 真正不被左右栏干扰居中 */
.view-3d {
    flex: 1;
    height: 100%;
    perspective: 1200px;
    display: flex;
    justify-content: center;
    align-items: center;
    background-image: url('BACKGROUND12A.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0.9;
    transition: background 0.5s ease;
    border-radius: 12px;
    position: relative;
}

/* ========== 已修复：3D容器居中 + 旋转中心 ========== */
.all-boxes {
    position: relative;
    transform-style: preserve-3d;
    cursor: grab;
    user-select: none;

    /* 必须给宽高，旋转中心才正确 */
    width: var(--center-size);
    height: var(--center-size);

     /* 真正 3D 居中原点 */
            transform-origin: center center center;
}

.cube {
    width: var(--box-size);
    height: var(--box-size);
    position: absolute;
    transform-style: preserve-3d;
     /* 让每个立方体自身居中在 3D 空间点上 */
            left: 50%;
            top: 50%;
            margin-left: calc(var(--box-size) / -2);
            margin-top: calc(var(--box-size) / -2);
}

#center {
    width: var(--center-size);
    height: var(--center-size);
    left: 50%;
            top: 50%;
            margin-left: calc(var(--center-size) / -2);
            margin-top: calc(var(--center-size) / -2);
            transform: translate3d(0,0,0);
            transform-style: preserve-3d;
            position: absolute;
}

        .face {
            position:absolute; width:100%; height:100%; border:2px solid #fff;border-radius: 6px; /* 圆角关键 */
            color:var(--text-color); font-size:var(--char-size); font-weight:bold;
            display:flex; align-items:center; justify-content:center; flex-direction:column; gap:4px; user-select:none;
        }
        .face.top { transform: rotateX(90deg) translateZ(var(--face-z)) rotate(90deg); }
        .face:hover { background:rgba(255,234,0,0.85)!important; box-shadow:0 0 18px rgba(180,140,255,0.7); z-index:99; }
        .front  { transform: translateZ(var(--face-z)); }
        .back   { transform: rotateY(180deg) translateZ(var(--face-z)); }
        .left   { transform: rotateY(-90deg) translateZ(var(--face-z)); }
        .right  { transform: rotateY(90deg) translateZ(var(--face-z)); }
        .bottom { transform: rotateX(-90deg) translateZ(var(--face-z)); }

        #front   { transform:translateZ(var(--box-space)); }
        #front1  { transform:translateZ(calc(var(--box-space)*2)); }
        #front2  { transform:translateZ(calc(var(--box-space)*3)); }
        #front3  { transform:translateZ(calc(var(--box-space)*4)); }
        #back    { transform:translateZ(calc(var(--box-space)*-1)); }
        #back1   { transform:translateZ(calc(var(--box-space)*-2)); }
        #back2   { transform:translateZ(calc(var(--box-space)*-3)); }
        #back3   { transform:translateZ(calc(var(--box-space)*-4)); }

        #left    { transform:translateX(calc(var(--box-space)*-1)); }
        #left1   { transform:translateX(calc(var(--box-space)*-2)); }
        #left2   { transform:translateX(calc(var(--box-space)*-3)); }
        #left3   { transform:translateX(calc(var(--box-space)*-4)); }
        #right   { transform:translateX(var(--box-space)); }
        #right1  { transform:translateX(calc(var(--box-space)*2)); }
        #right2  { transform:translateX(calc(var(--box-space)*3)); }
        #right3  { transform:translateX(calc(var(--box-space)*4)); }

        #top     { transform:translateY(calc(var(--box-space)*-1)); }
        #top1    { transform:translateY(calc(var(--box-space)*-2)); }
        #top2    { transform:translateY(calc(var(--box-space)*-3)); }
        #top3    { transform:translateY(calc(var(--box-space)*-4)); }
        #bottom  { transform:translateY(var(--box-space)); }
        #bottom1 { transform:translateY(calc(var(--box-space)*2)); }
        #bottom2 { transform:translateY(calc(var(--box-space)*3)); }
        #bottom3 { transform:translateY(calc(var(--box-space)*4)); }

        .pinyin { font-size:var(--pinyin-size); opacity:0.9; }

        #wordInfoPanel {
            position:fixed; top:60px; left:10px; width:150px;
            background:rgba(0,0,0,0.5); backdrop-filter:blur(6px);
            border-radius:10px; padding:10px; color:white;
            font-family:"Microsoft YaHei", sans-serif; z-index:9999; pointer-events:none;
        }
        #wordInfoPanel .main-char { font-size:90px; font-weight:bold; color:#ffeb3b; margin:0 20px; }
        #wordInfoPanel .pinyin { font-size:18px; color:#4caf50; margin:3px 0; }
        #wordInfoPanel .phrase { font-size:18px; color:#ffccbc; margin:3px 0; }
        #wordInfoPanel .radical { font-size:18px; color:#fff; margin:3px 0; }
        #wordInfoPanel .root { font-size:18px; color:#fff; margin:3px 0; }
        #wordInfoPanel .sentence { font-size:18px; color:#ffccbc; margin:3px 0; }
        #wordInfoPanel .english { font-size:18px; color:#87ceeb; margin:3px 0; }

        .control-barXXX {
            display:flex; gap:10px; justify-content:center; padding:10px; background:#fff;
        }
        /* 控制栏容器：标准弹性布局 */
        .control-bar {
            display: flex;
            align-items: center;
            justify-content: space-between; /* 左右自动分开 */
            width: 100%;
            max-width: 1300px;
            margin: 0 auto;
            padding: 10px 20px;
            gap: 12px; /* 按钮之间的间距 */
            position: relative;
        }

        /* 左侧组、右侧组：自动撑开 */
        .control-bar .left-group,
        .control-bar .right-group {
            display: flex;
            align-items: center;
            gap: 12px;
            flex: 1; /* 自动占满空间 */
        }
        .control-bar .left-group {
            justify-content: flex-start;
        }
        .control-bar .right-group {
            justify-content: flex-end;
        }

        /* LOGO 真正绝对居中 */
        .control-bar .logo {
            position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%, -50%);
            z-index: 10;
        pointer-events: none; /* 不遮挡点击 */
        }
        button { padding:6px 12px; cursor:pointer; border:none; border-radius:6px; background:#96775c; color:#fff; box-shadow: 0 4px 10px rgba(150, 119, 92, 0.3); }
        button:hover { background:#3672e0; }
        footer { background:#333; color:#fff; text-align:center; padding:10px; }

        /* 全屏底层遮罩 */
#adMask {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0,0,0,0.6);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 1;
  transition: opacity 1s ease;
}

/* 90%屏幕半透明背景图 */
.adContainer {
  position: relative;
  width: 70vw;
  height: auto;
  max-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* 半透明背景图 */
.adBgImage {
  width: 80%;
  height: auto;
  object-fit: contain;
  opacity: 0.75; /* 图片透明度 */
}

/* 叠加在图片上的广告词 */
.adText {
  position: absolute;
  color: #fff;
  font-size: 48px;
  font-weight: bold;
  text-align: center;
  text-shadow: 0 0 10px rgba(0,0,0,0.8);
  pointer-events: none;
}