style.css

/*import google font-Poppins */
@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap");
*{
    margin:0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Poppins",sans-serif;
}
body {
    height:100vh;
    display:flex;
    align-items: center;
    justify-content: center;
    background: #3434;

}
.container{
    position:relative;
    max-width: 500px;
    width: 500px;
    height:420px ;
    background: whitesmoke;
    border-radius: 10px;
    padding:20px;



}
header {
    font-size: 30px;
    border: 1px solid;
    border-radius: 10px;
    background-color: red;
    background-size: 500px;
    font-weight: 600;
    text-align: center;
    color: white;
    padding : 20px;
    margin: -20px;

}
textarea {
    width:450px;
    height:250px;
    border-radius: 8px;
    margin:20px 0px;
    padding:10px 15px;
    resize:none;
    outline: none;
    border: 1px solid #aaa;
}
button {
    width: 100%;
    padding: 14px 0;
    border: none;
    border-radius: 10px;
    color:#fff;
    background: red;
    cursor:pointer;
    

}
button:hover {
    background:blue;
}

.navigation {
    overflow: hidden;
   background-color: rgb(135, 154, 222);
   position: fixed;
   top: 0;
   width: 100%;
   text-decoration-color: red; 
}
.navigation a{
    font-style: italic;
    font-family: Arial, Helvetica, sans-serif;
    font-weight: bold;
    font-size: large;
    float: left;
    display: block;
    text-align: center;
    padding: 20px 18px;
    text-decoration: none;
}
a{
    margin-left:200px;
    color:red;
}