*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    font-family: Arial, Helvetica, sans-serif;
}
.container {
    min-height: 100vh;
    padding: 10px;
    background : linear-gradient(185deg, #3b3ee3,#045610);
}
.todo-app{
    max-width: 545px;
    background-color: #fff;
    margin:100px auto;
    padding:40px 30px 70px;
    border-radius: 5px;
}
.todo-app h2{
    color:#002765;
    display: flex;
    align-items: center;
    margin-bottom: 30px;
}
.todo-app h2 img{
    width: 35px;
    margin-left: 10px;
}
.todo-app:hover{
    box-shadow:1px 2px 2px 3px black;

}
.row{
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-color: #efe2e2;
    border-radius: 10px;
    padding-left: 20px;
    margin-bottom: 25px;
}
input{
    flex:1;
    border:none;
    outline: none;
    background: transparent;
    padding:10px;
    font-weight: 14px;
}
button{
    font-size: 16px;
    border:none;
    outline:none;
    padding:16px 50px;
    color:#fff;
    cursor:pointer;
    background-color: #0a9c11;
    border-radius: 10px;
}
button:hover{
    background-color: #068051;
}
ul li{
    list-style: none;
    font-size: 17px;
    padding: 12px 8px 12px 50px;
    user-select: none;
    cursor: pointer;
    position: relative;
}
ul li::before{
    content:'';
    position: absolute;
    height: 28px;
    width: 28px;
    border-radius: 50%;
    background-image: url(unchecked.png);
    background-size: cover;
    background-position: center;
    top: 8px;
    left: 16px;
}
ul li.checked{
color: #555;
text-decoration: line-through;

}
ul li.checked::before{
   color: #666;
   background-image: url(checked.png);
}
ul li span{
    position:absolute;
    right: 0;
    top: 5px;
    width: 40px;
    height: 40px;
    font-size: 22px;
    color: #555;
    line-height: 40px;
    text-align: center;
    border-radius: 50%;
}

ul li span:hover{
    background: #f3f3f3;
}