#container{
    width: 360px;
    box-shadow: 0 0 3px rgba(0,0,0,0.1);
    margin: 100px auto;
    background: #f7f7f7;
}
.completed{
    color: gray;
    text-decoration: line-through;
}
h1{
    background: #2980b9;
    color: white;
    margin: 0px;
    padding: 10px 20px;
    text-transform: uppercase;
    font-size: 24px;
    font-weight: 100;
}
ul{
    list-style: none;
    margin: 0;
    padding: 0;
}
input{
    font-size: 18px;
    background: #f7f7f7;
    padding: 13px 13px 13px 20px;
    width: 100%;
    height: 40px;
    box-sizing: border-box;
    border: 3px solid rgba(0,0,0,0);
}
input:focus{
    background: #fff;
    border: 3px solid #2980b9;
    outline: none;
}
li{
    background: #fff;
    height: 40px;
    line-height: 40px;
    color: #666;
}
li:nth-child(2n){
    background-color: #f7f7f7;
}
body
{
background:    Linear-gradient(90deg, #2BC0E4 10%, #EAECC6 90%);
}
.fa-plus{
    float: right;
}
span{
background: #e74c3c;
    height: 40px;
    margin-right: 20px;
    text-align: center;
    color: white;
    width: 0;
    display: inline-block;
    transition: 0.2s linear;
    opacity: 0;
    
}
li:hover span{
    width: 40px;
opacity: 1.0;
}