.container {
    display: flex;
  
}

.main_li {
    font-size: 34px; 
    line-height: 1.2;
}

.sub_li {
    font-style: oblique 40deg;
    font-size: 24px; 
    font-family:  "Courier New";
}
.bran_li {
    font-style: oblique 40deg;
    font-size: 18px; 
}
.col{
    flex: 1;
    font-size: 16px;
}

.col-60 {
    text-align: left;
    flex: 60%;
    font-size: 16px;
}
.col-50 {
    line-height: 1.8;
    flex: 50%;
    font-size: 26px;
    text-align: left;
}
.col-c50 {
    line-height: 1.8;
    flex: 50%;
    font-size: 26px;
    text-align: center;
}
.col-40 {
    line-height: 1.8;
    text-align: left;
    flex: 40%;
    font-size: 26px;
}

.col-s40 {
    line-height: 1.8;
    text-align: left;
    flex: 40%;
    font-size: 16px;
}

.col-s50 {
    line-height: 1.8;
    text-align: left;
    flex: 50%;
    font-size: 14px;
}
.row{
    flex: 1;
    font-size: 18px;
    
}
.describe{
    font-size: medium;
}
em{
    color: #ED493C;
}
strong{
  color:cyan;
}
b{ font-family: sans-serif;
    color: plum;}

u{font-family: cursive;
    color: aquamarine;

}

i{
    font-style: italic;
    color: greenyellow;
}
.def{
    text-align: left;
}

p{text-align: left;}

.example{
    font-size: 25px;
    font-style: italic;
    font-family: Arial, Helvetica, sans-serif;
    color: #FEF9D9;
}

.title{
    text-align: center;
}
.noborder .reveal section img {
    background:none; 
    border:none; 
    box-shadow:none;
    }
    #characters {
        display: flex;
        justify-content: space-around;
        margin: 20px 0;
    }
    .character {
        text-align: center;
    }
    .character-img {
        width: 120px;
        height: 100px;
        border-radius: 50%;
    }
    .wide-img {
        width: 250px;
        height: 100px;
        
    }
    textarea {
        width: 200px;
        height: 50px;
        background-color: transparent;
        color: aqua;
    }

    button {
        width: 150px;
        height: 40px;
        background-color:  #a23;
        opacity: 0.8; 
        border: none;
        color: white;
        padding: 2px 2px;
        text-align: center;
        text-decoration: none;
        display: inline-block;
        font-size: 15px;
        margin-top: 3px;
        border-radius: 5px;
        cursor: pointer;
        transition: background-color 0.3s ease;
    }
    #lanzhou {width: 40px;
        border-radius: 20px 20px;}

    button:hover {
        background-color: #dd5566;;
    }


    svg {
        z-index: -1;
    }

   
    h3{
        text-align: center;
    }

    b.white{
        color: white;

    }
    b.orange{
        color: orange;

    }
    .system{
        font-size: 16pt;
        border: white solid;
        text-align: left;
        padding-top: 5px;
        padding-left: 50px;
        padding-bottom: 5px;
        width: 800px;
    }
    .maintext{
        font-size: 26px;
      
    }

    .maintext h5 {
  white-space: nowrap;
}
    .smtext{
        font-size: 20px;
      
    }
    .kl{
        text-align: left;
    }

    .kb{
        font-size: 38;
    }
  
    .bright {
        opacity: 0.9;
    }

    .dark {
        opacity: 0.1;
    }


    #left, #center, #right {
        transition: all 0.5s ease;
    }

    #left, #right {
        flex: 1;
        padding: 10pt;
    }

    #center {
        flex: 3;
        opacity: 0.9; /* Always bright */
    }

    #container1 {
        display: flex;
        width: 100%;
        height: 100%;
        font-family:'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
        font-size: 20pt;
    }

    iframe{
        padding: 10pt;
    }

    .tri-20 {
        line-height: 1.8;
        flex: 20%;
    }


    
    .align_right {
        display: flex;
        justify-content: flex-end; /* Ensures flex items are aligned to the right */
        text-align: right;
        width: 80%; /* Ensures the container takes the full width */
      /*   margin-left: auto; Pushes content to the right */
    }

    .align_just {
        display: flex;
         justify-content: space-evenly; /* Aligns images to the far left and right */
        width: 100%; /* Ensure the container takes up the full width of its parent */
    }
/* Three-Column Layout Styling (Optimized for Dark Theme) */
.three-col-container {
  display: flex;
  justify-content: space-around;
  align-items: flex-start;
  gap: 20px;
  margin-top: 30px;
}

/* 方案五：脉冲光效 */

/* 定义一个名为 "pulse" 的动画 */
@keyframes pulse {
  from {
    top: 5%;
    opacity: 1;
  }
  to {
    top: 95%;
    opacity: 0;
  }
}

.three-col-item {
  flex: 1;
  padding: 0 15px;
  text-align: left;
  font-size: 0.8em;
  position: relative;
}

/* 用 ::before 创建静态的、半透明的背景线 */
.three-col-item:not(:first-child)::before {
  content: '';
  position: absolute;
  left: 0;
  top: 5%;
  bottom: 5%;
  width: 1px;
  background: var(--r-link-color, #a23);
  opacity: 0.3; /* 背景线设为半透明 */
}

/* 用 ::after 创建移动的光点 */
.three-col-item:not(:first-child)::after {
  content: '';
  position: absolute;
  left: -1px; /* 覆盖在背景线上 */
  width: 3px;
  height: 10%; /* 光点的高度 */
  background: radial-gradient(
    circle, 
    #fff, /* 中心是白色 */
    var(--r-link-color-hover, #dd5566), /* 外围是亮红色 */
    transparent 70% /* 边缘是透明的，形成光晕 */
  );
  border-radius: 50%;
  
  /* 应用动画，让它无限循环 */
  animation: pulse 2.5s ease-in infinite;
}

.three-col-item:first-child {
  border-left: none;
}

.three-col-item h4 {
  text-align: center;
  color: #eee; /* 确保标题是亮的 */
  /* 使用主题中的链接颜色作为下划线，保持风格统一 */
  border-bottom: 2px solid var(--r-link-color, #a23);
  padding-bottom: 10px;
  margin-top: 0;
}

.three-col-item p,
.three-col-item li {
  color: #ddd; /* 确保正文和列表文字是亮的 */
}

.three-col-item ul {
  list-style-type: '✔ ';
  padding-left: 20px;
}
.three-col-item li {
    margin-bottom: 15px;
}

/* ============================================= */
/* ==  VISIBILITY FIXES FOR KATEX AND SVG      == */
/* ============================================= */

/* 1. 让 KaTeX 公式在深色背景下可见 */

/* 2. 让 SVG 图形在深色背景下可见 */
.tableau-svg text {
  fill: #eee; /* SVG 文字填充为亮色 */
}
.tableau-svg line {
  stroke: #eee; /* SVG 线条描边为亮色 */
}
.tableau-svg .branch-closed {
  /* 使用主题中链接悬停的亮红色，更醒目 */
  fill: var(--r-link-color-hover, #dd5566); 
  
}
.tableau-svg .branch-open1 {
  fill: #8f8; /* 用绿色表示开放分支，更清晰 */
}

/* ============================================= */
/* ==  SLIDE 3: TWO-COLUMN & DIAGRAM STYLES    == */
/* ============================================= */

.subtitle {
  font-size: 0.8em;
  color: #ccc;
  margin-top: -20px;
  margin-bottom: 40px;
}

.two-col-container {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px; /* 两栏之间的间距 */
}

.col-left {
  flex: 1; /* 左栏占据可用空间的一半 */
  text-align: left;
  font-size: 0.9em;
}

.col-right {
  flex: 1; /* 右栏占据可用空间的一半 */
  display: flex;
  justify-content: space-around; /* 让图示横向排列 */
  align-items: flex-start;
}

.col-left h4 {
  color: #eee;
  border-bottom: 1px solid var(--r-link-color, #a23);
  padding-bottom: 10px;
  margin-top: 0;
}

.col-left ul {
  list-style-type: none;
  padding-left: 0;
}

.col-left li {
  margin-bottom: 20px;
  padding-left: 25px;
  position: relative;
}

.col-left li::before {
  content: '🌲'; /* 用树的图标作为列表符号 */
  position: absolute;
  left: 0;
  top: 0;
  color: var(--r-link-color, #a23);
}


/* Styling for diagrams in the right column */
.diagram-container {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.diagram-title-ok, .diagram-title-bad {
  margin: 0 0 10px 0;
  font-size: 0.7em;
  font-weight: bold;
}
.diagram-title-ok {
  color: #8f8; /* 绿色 */
}
.diagram-title-bad {
  color: #f88; /* 红色 */
}

.tree-diagram .tree-node {
  fill: #eee;
  stroke: #999;
  stroke-width: 1;
}

.tree-diagram .tree-edge {
  stroke: #eee;
  stroke-width: 1;
}

.tree-diagram .error-path {
  /* 使用主题中的亮红色来高亮错误路径 */
  stroke: var(--r-link-color-hover, #dd5566);
  stroke-width: 2;
  stroke-dasharray: 4 2; /* 虚线效果 */
}

/* ============================================= */
/* ==  SLIDE 5: STATIC RULES & DEMO LAYOUT     == */
/* ============================================= */


.two-col-container-static {
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  gap: 20px;
  height: 85%;
}

/* Left column for the rules toolbox */

.rules-toolbox h4 {
    width: 90%;
    text-align: center;
    color: #eee;
    margin: 15px 0 10px 0;
    font-size: 0.9em;
}
.rules-toolbox hr {
    width: 80%;
    border: 0;
    border-top: 1px solid var(--r-link-color, #a23);
    margin: 10px 0;
}
.rules-toolbox .rule-svg {
    width: 80%;
    height: auto;
    max-height: 120px;
}
.rules-toolbox .rule-svg text, 
.rules-toolbox .rule-svg line {
    stroke: #ddd;
    fill: #ddd;
    font-size: 22px;
    stroke-width: 1;
}


.rules-toolbox {
  flex: 4.5; 
  display: flex;
  flex-direction: column;
   justify-content: flex-start; 
  align-items: center;
  padding-top: 0; /* 移除内边距，让flexbox完全控制居中 */
}

.rules-compact-grid {
    display: flex;
    flex-wrap: wrap; 
    justify-content: center;
    align-items: center;
    gap: 20px 10px;
}

.rule-svg-compact {
    width: 100px; /* 再次增大SVG容器尺寸 */
    height: 140px;
}

.rule-svg-compact text {
    fill: #eee;
    font-size: 24px; /* 修改：再次显著增大字体 */
    font-family: "Palatino Linotype", "Book Antiqua", Palatino, serif; /* 换一个更优雅的衬线字体 */
    font-weight: bold; /* 加粗 */
}

.rule-svg-compact line {
    stroke: #eee;
    stroke-width: 1px;   /* 修改：将线条变细，突出文字 */
}


/* Right column for the demo canvas */
.demo-canvas {
  flex: 5.5; 
  padding: 10px 10px 10px 40px;
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative; 
}



.demo-canvas h4 {
    color: #eee;
}


#demo-tree-svg-static {
    width: 100%;
    height: 100%;
}
#demo-tree-svg-static .tree-text {
    fill: #eee;
    font-size: 20px;
    font-family: monospace;
}
#demo-tree-svg-static .tree-line {
    stroke: #eee;
    stroke-width: 1.5;
}
#demo-tree-svg-static .branch-closed {
    fill: var(--r-link-color-hover, #dd5566);
    font-size: 28px;
    font-weight: bold;
}

/* 让 fragment 平滑地淡入 */
.reveal .slides section .fragment {
  opacity: 0;
  transition: opacity 0.5s ease-in-out;
}
.reveal .slides section .fragment.visible {
  opacity: 1;
}

/* List of literals from the open branch */
.literal-list {
    list-style: none;
    padding: 0;
    margin: 15px 0;
    font-size: 0.8em;
    color: #ddd;
    text-align: center;
}
.literal-list .literal {
    font-family: monospace;
    color: var(--r-link-color-hover, #dd5566);
    background: rgba(255,255,255,0.1);
    padding: 2px 5px;
    border-radius: 4px;
}
.literal-list .value {
    font-weight: bold;
    color: #8f8;
}
.countermodel-canvas {
  flex: 4.5; /* 占据剩余空间 */
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 20px;
  font-size: 0.8em;
}

/* Styling for the generated truth table */
.truth-table {
  width: 100%;
  margin-top: 20px;
  border-collapse: collapse;
  font-size: 0.9em;
}
.truth-table th, .truth-table td {
  border: 1px solid #555;
  padding: 10px;
  text-align: center;
}
.truth-table th {
  color: var(--r-link-color, #a23);
  font-weight: bold;
}
.truth-table td {
  color: #eee;
  font-family: monospace;
}
.truth-table .true {
  color: #8f8; /* Green for TRUE */
  font-weight: bold;
}
.truth-table .false {
  color: #f88; /* Red for FALSE */
  font-weight: bold;
}

/* Styling for highlighting the open branch in the SVG */
.open-branch-highlight {
  fill: var(--r-link-color, #a23);
  opacity: 0.2;
  stroke: var(--r-link-color-hover, #dd5566);
  stroke-width: 2px;
  stroke-dasharray: 4 2;
}
.branch-open {
    fill: #8f8;
    font-size: 24px;
    font-weight: bold;
}
/* ======================================================== */
/* ==  SLIDES 2 & 3: TRUTH TABLE & DERIVATION STYLES   == */
/* ======================================================== */
.two-col-container-static1 {
  display: flex;
  justify-content: space-between;
  align-items: center; /* 修改：让两栏内容垂直居中对齐 */
  gap: 10px;
  height: auto;
  margin-top: 10px;
}
/* Styling for the truth tables */
.truth-table-demo {
  margin: 20px auto;
  border-collapse: collapse;
  font-size: 0.8em;
  box-shadow: 0 0 10px rgba(0,0,0,0.15);
}
.truth-table-demo thead tr {
  background-color: var(--r-link-color, #a23);
  color: #ffffff;
  text-align: center;
}
.truth-table-demo th,
.truth-table-demo td {
  padding: 12px 15px;
  border: 1px solid #ddd;
}
.truth-table-demo tbody tr {
  border-bottom: 1px solid #dddddd;
}
.truth-table-demo tbody tr:nth-of-type(even) {
  background-color: #f3f3f3;
}
.truth-table-demo .result-column {
  background-color: rgba(162, 51, 35, 0.2); /* Light red background for result column */
  font-weight: bold;
  text-align: center;
}
.truth-table-demo .counterexample-row {
    background-color: rgba(221, 85, 102, 0.4) !important; /* Highlight for counterexample row */
}
.truth-table-demo .highlight-row {
    background-color: rgba(144, 238, 144, 0.3) !important; /* Light green for highlighted rows */
}


/* Box for the analysis text */
.analysis-box {
    margin-top: 30px;
    font-size: 0.9em;
}
.analysis-box p {
    margin: 10px 0;
}
.analysis-box i {
    margin-right: 10px;
    color: var(--r-link-color, #a23);
}

/* Styling for the derivation box on slide 3 */
.derivation-box {
    text-align: left;
    padding-left: 30px;
}
.derivation-box p {
    font-size: 0.9em;
}
.derivation-box .minterm-list {
    list-style: none;
    padding-left: 20px;
    font-size: 0.8em;
}
.derivation-box .minterm-list li {
    margin-bottom: 10px;
}
.derivation-box code {
    font-family: monospace;
    background: #eee;
    padding: 2px 5px;
    border-radius: 4px;
    color: #333;
}
.derivation-box .conclusion-text {
    margin-top: 20px;
    font-weight: bold;
    color: var(--r-link-color, #a23);
}


/* ======================================================== */
/* ==  SLIDE 4: KARNAUGH MAP STYLES (REFINED VERSION)    == */
/* ======================================================== */


/* ======================================================== */
/* ==  SLIDE 4: KARNAUGH MAP STYLES (WIDTH CORRECTED)    == */
/* ======================================================== */

/* 右栏：卡诺图容器 */
.k-map-container {
  flex: 6;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.k-map-wrapper {
    margin-bottom: 20px;
}

/* 卡诺图表格本身 */
.k-map-table {
  border-collapse: collapse;
  font-size: 1.1em;
}

/* 普通单元格的样式 */
.k-map-table th, .k-map-table td {
  border: 1px solid #ccc;
  width: 55px;  /* 修改：恢复到合理的单元格宽度 */
  height: 55px; /* 修改：恢复到合理的单元格高度 */
  text-align: center;
  font-family: monospace;
  transition: background-color 0.5s ease-in-out;
}
.k-map-table th {
  background: #f8f8f8;
  font-weight: bold;
  color: #555;
  border: 1px solid #ccc;
}
.k-map-table td {
    font-weight: bold;
}

/* 新增：专门为左上角单元格设置样式 */
.k-map-table .k-map-corner {
    width: 80px; /* 给予更宽的空间 */
    white-space: nowrap; /* 强制不换行 */
}


/* 单元格高亮样式 */
.k-map-table td.group-1 {
    background-color: rgba(162, 51, 35, 0.3);
}
.k-map-table td.group-2 {
    background-color: rgba(0, 123, 255, 0.3);
}
.k-map-table td.group-3 {
    background-color: rgba(54, 6, 37, 0.3);
}

/* 图例样式 */
.k-map-legend {
    width: 100%;
    margin-top: 10px;
    font-size: 0.8em;
    text-align: center;
}
.k-map-legend ul {
    list-style: none;
    padding: 0;
    display: inline-block;
    text-align: left;
}
.k-map-legend li {
    margin-bottom: 15px;
}
.k-map-legend .color-box {
    display: inline-block;
    width: 20px;
    height: 20px;
    border-radius: 5px;
    margin-right: 10px;
    vertical-align: middle;
    border: 1px solid #ccc;
}
.k-map-legend .color-box.group-1 {
    background-color: rgba(162, 51, 35, 0.3);
}
.k-map-legend .color-box.group-2 {
    background-color: rgba(0, 123, 255, 0.3);
}

/* 最终公式样式 */
.final-expression {
    margin-top: 20px;
    font-size: 0.9em;
    font-weight: bold;
    text-align: center;
}

/* ======================================================== */
/* ==  SLIDES 5 & 6: K-MAP EXERCISE STYLES               == */
/* ======================================================== */

.k-map-exercise {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 100%;
  height: 100%;
}
/* ======================================================== */
/* ==  FINAL SLIDE: APPLICATIONS STYLES                  == */
/* ======================================================== */

.app-container {
    flex: 1;
    padding: 0 20px;
}

.app-container h4 {
    font-size: 1.2em;
    color: var(--r-main-color);
    border-bottom: 2px solid var(--r-link-color, #a23);
    padding-bottom: 10px;
    margin-bottom: 30px;
}

.app-container h4 i {
    margin-right: 15px;
}

.app-list {
    list-style: none;
    padding: 0;
}

.app-list li {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
}

.app-list li i {
    font-size: 1.5em;
    color: var(--r-link-color, #a23);
    margin-top: 5px;
    margin-right: 20px;
    width: 30px; /* Ensure consistent icon alignment */
    text-align: center;
}

.app-list li p {
    margin: 5px 0 0 0;
    font-size: 0.8em;
    color: #555; /* Slightly dimmer text for descriptions */
}

/* Styles for the workflow diagram */
.workflow-diagram {
    width: 100%;
    max-width: 300px; /* Limit max width */
    height: auto;
}
.workflow-diagram .workflow-box {
    fill: #f9f9f9;
    stroke: var(--r-link-color, #a23);
    stroke-width: 1.5;
}
.workflow-diagram .workflow-text {
    font-size: 10px;
    font-family: var(--r-main-font);
    text-anchor: middle;
    fill: #333;
}
.workflow-diagram .workflow-arrow {
    stroke: #333;
    stroke-width: 1.5;
}
.workflow-diagram .workflow-label {
    font-size: 8px;
    font-style: italic;
    text-anchor: middle;
    fill: #555;
}

img.logo:active {
  transform: scale(0.95);
  opacity: 0.8;
}
.litlist li { 
  margin-bottom: 0.4em; 
  list-style: "📘 ";
  font-size: 90%;
}

.rule {
  background: rgba(255,255,255,0.05);
  border-left: 4px solid #00ccff;
  padding: 3px;
  border-radius: 8px;
}
.traits li { margin: 0.3em 0; }
.example { color: #ccc; }
.legend small { color: #ccc; }
p.example { background: rgba(255,255,255,0.05); padding: 8px; border-radius: 8px; }

.axiom {
  background: rgba(255,255,255,0.08);
  padding: 6px;
  margin: 4px 0;
  border-left: 4px solid #00ccff;
  border-radius: 4px;
}

.tutorial {
            background-color: #fff;
            color: #333; /* 教程使用亮色背景 */
            padding: 20px;
            border-radius: 5px;
            box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.1);
            text-align: left;
        }
        .tutorial ul { list-style-type: disc; padding-left: 30px; }
        .tutorial li { margin-bottom: 10px; }
        .example { background-color: #f0f0f0; padding: 2px 5px; border-radius: 3px; font-family: monospace; }
        
        #network {
            border: 1px solid white;
            background-color: #fff; /* SVG 背景设为白色 */
        }


        .cy {
            width: 1200px;
            height: 600px;
            border: 1px solid white;
            background-color: #fff; /* SVG 背景设为白色 */
            overflow: auto; /* 如果内容溢出，允许滚动 */
        }

        .selected {
            fill: #007bff;
            cursor: move;
        }
        .definition-box {
            background-color: #f9f9f9;
            color: #333; /* 亮色背景，深色文字 */
            border: 1px solid black;
            max-width: 1000px;
            padding: 10px;
            margin-top: 10px;
            width: 100%;
            text-align: left;
            font-size: 0.8em; /* 缩小字体以容纳更多文本 */
        }
        .axioms { margin-top: 10px; }
        .content {
            font-family: Arial, sans-serif;
            max-width: 1000px;
            padding: 20px;
            text-align: left;
        }
        .definition {
            border: 1px solid #ccc;
            padding: 20px;
            margin-top: 20px;
            color: #333;
            background-color: #fff;
        }
        .verification{
            font-family: Arial, sans-serif;
            max-width: 1000px;
            padding: 20px;
            color:brown;
        }
        
        /* 用于 Belief Output 的特定样式 */
        #beliefOutput {
            background: #333;
            border-left: 4px solid #007bff;
            padding: 15px;
            font-family: monospace;
            font-size: 1.1em;
            white-space: pre-wrap;
            color: #fff;
        }
        #satisfaction {
            
            font-weight: bold;
            color: #42affa;
        }

        .tableau-rule {
            font-family: monospace, sans-serif;
            text-align: center;
            margin-bottom: 1.0em;
            font-size: 0.40em; /* 缩小字体以适应空间 */
            line-height: 1.4;
        }
        .rule-name {
            font-weight: bold;
            font-size: 0.8em;
            color: #eee;
        }
        .rule-premise {
            border: 1px solid #999;
           
            display: inline-block;
            
        }
        .rule-conclusion {
            border: 1px solid #999;
         
            display: inline-block;
           
        }
        .rule-branch-container {
            display: flex;
            justify-content: center;
            align-items: flex-start;
        }
        .rule-branch {
            padding: 0 10px;
        }
        .arrow {
            color: #999;
            font-size: 1.2em;
            margin: 0;
            padding: 0;
            line-height: 1;
        }
        .rules-compact-grid-custom {
            display: grid;
            grid-template-columns: 1fr 1fr; /* 两列布局 */
            gap: 2px;
        }
       .tinytext{
        font-size: 13.5pt;
       }

       .tableau-container-svg {
            background-color: #2b2b2b;
            border: 1px solid #555;
            padding: 5px;
            border-radius: 8px;
            max-width: 90%;
            margin: 0 auto;
        }

        .tableau-container-svg  {
            font-size: 0.55em;
            text-align: center;
            border-bottom: 1px solid #555;
            padding-bottom: 5px;
            margin-bottom: 10px;
            /* 确保 Unicode 文本正确显示 */
            font-family: "DejaVu Sans", "Arial Unicode MS", sans-serif;
        }

        .tableau-container-svg .tree2-text {
            /* 字体缩小，并使用支持 Unicode 的字体 */
            font-size: 10px; 
            font-family: "DejaVu Sans", "Arial Unicode MS", sans-serif;
            fill: #eee;
        }

        .tableau-container-svg .tree-line {
            stroke: #999;
            stroke-width: 1.5;
        }

        .tableau-container-svg .branch2-closed {
            font-size: 10px;
            font-family: "DejaVu Sans", "Arial Unicode MS", sans-serif;
            fill: #ff6b6b; /* 闭合分支的颜色 */
            font-weight: bold;
            font-style: italic;}

    .branch2-open{
        font-size: 10px;
            font-family: "DejaVu Sans", "Arial Unicode MS", sans-serif;
            fill: #8f8;
            font-weight: bold;
            font-style: italic;

    }

    .proof-step {
            width: 100%;
            
        }
        .proof-grid {
            display: grid;
            grid-template-columns: 60% 40%; /* 6:4 分栏 */
            gap: 10px;
            text-align: left;
            font-size: 0.7em;
            align-items: center; /* 垂直居中 */
            margin-top: 1em;
        }
        .proof-row-math {
            text-align: right;
            padding-right: 15px;
            border-right: 1px solid #555; /* 中间加一条分割线，可选 */
        }
        .proof-row-reason {
            padding-left: 15px;
            font-style: italic;
            color: #aaa;
        }
        .step-title {
            text-align: left;
            color: #42affa; /* 标题高亮颜色 */
            margin-bottom: 0.5em;
            font-size: 0.9em;
            border-bottom: 1px solid #444;
            padding-bottom: 5px;
        }