.kmath_md p code {
    background-color: #EF5D2A;
    color: #ffffff;
    padding: 3px 10px 3px 10px
}

.kmath_md ol  li {list-style:decimal; margin-left:20px;}

#preview table {
    width: 100%;
    margin-bottom: 1rem;
    background-color: transparent;
    border-collapse: collapse;
    border: 1px solid #dee2e6;
}

    #preview table th {
        background-color: #dee2e6
    }

    #preview table th,
    #preview table td {
        padding: 0.2rem;
        vertical-align: top;
        border-top: 1px solid #dee2e6;
    }


    #preview table thead th {
        vertical-align: bottom;
        border-bottom: 2px solid #dee2e6;
    }

    #preview table tbody tr:nth-of-type(even) {
        background-color: rgba(0, 0, 0, 0.02);
    }


#preview th,
#preview td {
    border: 1px solid #dee2e6;
}
 


 
#div_cnt {
    margin: 0px;
    display: flex
}

.thedt {
    font-size: 12px;
    color: gray;
    margin: 16px 0px
}

.main_content {
    margin: 20px;
    width: 100%;
}

.kmath_md {
    font-family: Optima, "Microsoft YaHei", PingFangSC-regular, serif;
    line-height: 35px;
    font-size:16px;
}

    .kmath_md h1 {
        font-weight: 300;
        letter-spacing: -.01em;
    }

    .kmath_md h2 {
        background-color: rgb(239, 112, 96);
        color: #ffffff;
        display: table;
        padding: 3px 10px;
        font-size: 1.5625em;
        line-height: 1.4;
        margin: 1.6em 0 .64em;
        font-weight: 300;
        letter-spacing: -.01em;
    }

    .kmath_md h3 {
        background-color: burlywood;
        color: #ffffff;
        display: table;
        padding: 3px 10px;
        font-size: 1.2em;
        line-height: 1.4;
        margin: 1.6em 0 .64em;
        font-weight: 300;
        letter-spacing: -.01em;
    }

    .kmath_md h4 {
        background-color: blueviolet;
        color: #ffffff;
        display: table;
        padding: 3px 10px;
        font-size: 1em;
        line-height: 1;
        margin: 1.3em 0 .6em;
        font-weight: 300;
        letter-spacing: -.01em;
    }

    .kmath_md blockquote {
        margin: 20px 0px;
        padding: 10px;
        padding-left: 20px;
        line-height: 1.8;
        border-left: solid 3px rgb(239, 112, 96);
        background-color: rgb(255, 249, 249);
    }

    .kmath_md a {
        color: rgb(239, 112, 96);
    }

    .kmath_md p img {
        max-width: 780px;
    }

.idx {
    margin: 10px;
}

.ad img{ height:200px; }

@media screen and (max-width:600px) {
    #div_cnt {
        margin: 20px;
    }

    .main_content {
        margin: 0px;
        width: 100%;
    }

    .kmath_md p img {
        max-width: 95%;
        margin-bottom: 20px;
    }

    .ad .gzh, .ad .zfb {
        display: none
    }

    
}

.zz {
    border-top: dotted 1px #ccc;
    margin: 10px 0px;
    padding: 10px;
    font-size: 13px
}

a.x {
    color: dodgerblue
}


.ztree li span.button.switch {
    width: 20px;
    height: 20px
}

.ztree li span.button.center_open {
    background-position: -90px -16px;
}




.kmath_md pre {
    background-color: rgba(27, 31, 35, .05);
    line-height: 23px;
    padding: 10px;
    border-radius: 10px;
}

    .kmath_md pre code {
        padding: 2px;
        margin: 0;
        font-size: 85%;
        line-height: 10px;
        border-radius: 3px;
        font-family: mononoki, Consolas, "Liberation Mono", Menlo, Courier;
        word-break: break-word;
        white-space: pre-wrap;
        color: #a50
    }



 
     .kmath_md  details {
  border: 2px solid #448aff;
  border-radius: 4px;
  padding: 0.5em 0.5em 0;
margin-top:1em;
}

   .kmath_md summary {
  font-weight: bold;
  margin: -0.5em -0.5em 0;
  padding: 0.5em;
}

   .kmath_md details[open] {
  padding: 0.5em;
}

   .kmath_md details[open] summary {
  border-bottom: 1px solid red;
  margin-bottom: 0.5em;
}