index.css

*{
    margin: 0;
    padding: 0;
    list-style: none;
    text-decoration: none;
    box-sizing: border-box;
}
html{
    height: 100%;
}
body{
    width: 100%;
    height: 100vh;
    background: #FFF;
    overflow: hidden;
}
.header{
    height: 80px;
    background: black;
}
#el{
    width:100%;
    height: 100%;
}
.content{
    position: relative;
    width: 100%;
    height:90%;
}
.note{
    width: 240px;
    position: absolute;
    top:200px;
    height: auto;
    left: 120px;
    border:1px solid black;
}
.note .title{
    cursor: pointer;
    height: 40px;
    /*border:1px solid black;*/
    text-align: center;
    line-height: 40px;
    color: #FFF;
}
.note .content{
    min-height: 300px;
    padding: 15px;
    background: #fff;
}
.pink{
    background: red;
}
.red{
    background: pink;
}
.blue{
    background: blue;
}
.black{
    background: black;
}
.note textarea{
    width: 100%;
    min-height: 200px;
    outline: none;
    resize: none;
    border: none;
}
.title{
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    height: 40px;
    background: red;
    text-align: center;
    line-height: 40px;
    color: #fff;
    cursor: pointer;
}
button{
    position: absolute;
    top:0;
    right: 0;
    width: 20px;
    height:20px;
    opacity: 0;
}