style.css

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
.container{
    width: 100%;
    height: 100vh;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    background-image: url(first.jpg);
}
.box{
    width: 80%;
    margin: auto;
    text-align: center;
    padding-top: 100px;
}
.box h1{
    color: white;
    font-size: 50px;
}
.row{
    display: flex;
    justify-content: space-between;
    margin-top: 5%;
    height: 40px;
}
.box-col{
    flex-basis: 31%;
    height: 300px;
    background: transparent ;
    border: 1px dashed white;
    border-radius: 25px;
    margin-bottom: 5%;
    padding: 30px 12px;
    box-sizing: border-box;
}
@media(max-width:700px){
    .row{
        flex-direction: column;
        }
    
    .container{
    width: 100%;
    height: 900px;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    background-image: url(first.jpg);}
    
    .btn a button{
        text-decoration: none;
        width: 100px;
        height: 25px;
        margin-top: 20px;
        border-radius: 25px;
        border-color: black;
        font-family: 'Times New Roman', Times, serif;
    }
    .box-col{
        flex-basis: 31%;
        height: 325px;
        background: transparent ;
        /* border: 1px dashed white; */
        border-radius: 25px;
        margin-bottom: 5%;
        padding: 30px 12px;
        box-sizing: border-box;
    }
}
.col-25 label{
    color: white;
    font-size: 20px;
}
.col-75 input{
    height: 20px;
    width: 150px;
    border-radius: 10px;
    border-color: black;
}
.col-75 ::placeholder{
    color: black;
}
.btn a button{
    text-decoration: none;
    width: 100px;
    height: 25px;
    border-radius: 25px;
    border-color: black;
    font-family: 'Times New Roman', Times, serif;
}