index.css

*{
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body{
    width: 100vw;
    height: 100vh;
    background-color: #f9f9f5;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container{
    background-color: #fff;
    width : 400px;
    border-radius: 5px;;
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}
h2{
    text-align: center;
    padding: 10px 20px;;
}

.container form{
    padding: 20px 40px;

}
.form-handler{
    margin-bottom: 10px;
    padding-bottom: 10px;
    position: relative;

}
.form-handler label{
    display: block;
    color: rgba(156, 163, 175,1);
    font-size: 18px;
    margin-bottom: 5px;

}

.form-handler input{
    display: block;
    font-size: 18px;
    margin-bottom: 8px;
    padding: 2px;
    border: 2px solid #f0f0f0;
    width: 100%;
    border-radius: 5px;
}

.form-handler input:focus{
    outline: none;
    border-color: #777;
}
.form-handler.success input{
    border-color: #2ecc71;
}
.form-handler.error input{
    border-color: #e74;
}

.form-handler small{
    position:absolute;
    left: 0;
    bottom : 0;
    color: #e74;
    visibility: hidden;
}

.form-handler.error small{
    visibility: visible;
}

.form-handler button{
    background-color: #3498db;
    border-radius: 5px;
    font-size: 16px;
    width: 100%;
    /* margin: 10px; */
    padding:5px;
    color: #fff;
}