register.css

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-srif;
}

body{
    display: flex;
    height: 100vh;
    justify-content: center;
    align-items: center;
    padding: 10px;
    background: url(images/wallpaper3.jpg);
    background-repeat: no-repeat;
    
}

.container{
    max-width: 700px;
    width: 100%;
    background: #fff;
    padding: 25px 30px;
    border-radius: 10px;
    margin-top: 100px;
    margin-bottom: 100px;
}

.container .title{
    font-size: 25px;
    font-weight: 500;
    position: relative;
}

.container .title::before{
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    height: 3px;
    width: 30px;
    background: linear-gradient(135deg, #71b7e6, #9b59b6)
}

.container form .user-details{
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    margin: 20px 0 12px 0;
}

form .user-details .input-box{
    margin: 20px 0 12px 0;
    width: calc(100% / 2 - 20px)
}

.user-details .input-box .details{
    display: block;
    font-weight: 500;
    margin-bottom: 5px;
}

.user-details .input-box input{
    height: 45px;
    width: 100%;
    outline: none;
    border-radius: 5px;
    border: 1px solid #ccc;
    padding-left: 15px;
    font-size: 16px;
    border-bottom-width: 2px;
    transition: all 0.3s ease;
}

.user-details .input-box input:focus{
    border-color: #9b59b6;
}

form .gender-details .gender-title{
    font-size: 20px;
    font-weight: 500;
}
form .gender-details .category{
    display: flex;
    width: 80%;
    margin: 14px 0;
    justify-content: space-between;
}

.gender-details .category label{
    display: flex;
    align-items: center;
}

.gender-details .category .dot{
    height: 18px;
    width: 18px;
    background: #d9d9d9;
    border-radius: 50%;
    margin-right: 10px;
    border: 5px solid transparent;
    transition: all 0.3s ease;
}

#dot-1:checked ~ .category label .one,
#dot-2:checked ~ .category label .two,
#dot-3:checked ~ .category label .three{
    border-color: #d9d9d9;
    background: #9b59b6;
}

form input[type="radio"]{
    display: none;
}

.tbl{

    display: table;
}


form .button{
    height: 45px;
    width: 500px;
    align-items: center;
    margin-top: 50px;
}

#button1 {
    margin-left: 20%;
    float: left;
    width: 30%;

}
#button2 {
    margin-left: 20px;
    float: right;
    width: 30%;
}

form .button input{
    height: 100%;
    width: 50%;
    outline:none;
    color: #fff;
    border: none;
    font-size: 18px;
    font-weight: 500;
    letter-spacing: 1px;
    background: linear-gradient(135deg, #04375a,#000);
}

a.link{
    color: #111;
    font-size: 14px;
    font-weight: bold;
    text-decoration: none;
}

form .button input:hover{
    background-color: linear-gradiend(-135deg, #71b7e6, #9b59b6);
}

@media (max-width: 584px) {
    .container{
        max-width: 100%;
    }
    form .user-details .input-box{
        margin-bottom: 15px;
        width: 100%;
    }
    form .gender-details .category{
        width: 100%;
    }
    .container form .user-details{
        max-height: 300px;
        overflow-y: scroll;
    }
    .user-details::-webkit-scrollbar{
        width: 0px; 
    }
}