:root {
    --nav-width: 360px;
    --gap: 20px
}

html,body {
    height: 100%;
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 15px;
    line-height: 1.45;
    background: #fff;
    color: #111
}
 .contentcontainer{
    width: 100vw;
    min-height: 100vh;
    display: flex;
    flex-direction: row;
    
    
    
}
.leftside{    
    height: auto;
    width: 20%;
    padding: 10px;


}
.rightside{
    margin: 0;
    width: 100%;
    height: auto;
    /*display: flex;
    justify-content: end;*/
    
}
img {
  /*display: block;*/
  margin: auto;
  width: 100%;
  height: auto ;
  border: 1px solid black;
}
/*.container {
    display: flex;
    min-height: 100vh
}

.content {
    flex: 1;
    padding: 28px 32px 48px 32px;
    overflow: auto
}*/

nav {
    width: var(--nav-width);
    background: #f7f8fb;
    border-left: 1px solid #e3e7ee;
    padding: 18px;
    box-sizing: border-box;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow: auto;
    order: 2
}

nav h2 {
    margin: 0 0 12px 0;
    font-size: 18px
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 0
}

nav li {
    margin: 6px 0
}

nav a {
    color: #0b66b2;
    text-decoration: none
}

nav a:hover {
    text-decoration: underline
}

/* Click-to-toggle using checkbox */
.collapsible {
    margin: 6px 0
}

.collapsible input {
    display: none
}

.collapsible label {
    display: block;
    cursor: pointer;
    padding: 6px 8px;
    border-radius: 4px
}

.collapsible label:after {
    content: '▸';
    float: right;
    transition: transform .2s
}

.collapsible input:checked+label:after {
    transform: rotate(90deg)
}

.collapsible .inner {
    max-height: 0;
    overflow: hidden;
    transition: max-height .25s ease
}

.collapsible input:checked+label+.inner {
    max-height: 1000px;
    padding-left: 8px;
    margin-top: 6px
}

header {
    border-bottom: 1px solid #eee;
    padding-bottom: 12px;
    margin-bottom: 14px
}

h1 {
    font-size: 22px;
    margin: 6px 0
}

h2.chapter {
    font-size: 20px;
    margin-top: 28px;
    border-bottom: 1px solid #eee;
    padding-bottom: 6px
}

.page-img {
    display: block;
    max-width: 100%;
    margin: 12px 0;
    border: 1px solid #e6e6e6;
    padding: 4px;
    background: #fff
}

:target {
    scroll-margin-top: 20px
}

@media(max-width:900px) {
    nav {
        position: relative;
        width: 100%;
        height: auto;
        border-left: none;
        border-top: 1px solid #eee
    };

    .container {
        flex-direction: column
    }
}