*{
        padding: 0;
        margin: o;
}
body{
        background-color: aliceblue;
        display: flex;
        justify-content: center;
        align-items: center;
        height: 100vh;
        box-sizing: border-box;
       
}
.container{
        margin: 15px;
        padding: 15px;
        border: 1px solid white;
        width:100%;
        max-width: 450px;
        background: linear-gradient(45deg,  white, grey);
        display:flex;
        flex-direction: column;
        text-align: center;
        
}
h1{
       color: red;
       font-family: sans-serif;
       font-size: 45px;
}
input{
        height: 70px;
        border: 5px 5px solid black ins;
        border-radius: 15px;
        font-size:25px;
        text-align: center;
        justify-content: space-between;
        
        
}
input:focus{
        
        outline: none;
}
button{
        padding: 20px;
        margin-top: 25px;
        border-radius: 15px;
        background-color:  blue;
        font-size: 1rem;
        transition: all  6s ease-in-out;
}
button:active {
      transform: scale(1.1);
      background-color: darkblue;
      font-weight:600 ;
        
}
li {
    font-size: 20px;
    background-color: #f4f4f4;
    border-radius: 5px;
    list-style: none;
    height:3.5rem;
    position: relative;
    opacity:70%;
    padding: 4px;
    margin-bottom: 30px;
}
.completed {
    text-decoration: line-through;
    color: gray;
    opacity: 0.7;
}