style.css

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

body{
    background-color: rgb(231, 231, 231);
    height: 300vh;
}

nav{
    width: 100%;
    height: 75px;
    background-color:rgb(255, 255, 255) ;
    position: fixed;
    top:0;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

@media screen and (max-width:900px) {
    .main{
        display: grid;
        grid-template-columns: 1fr;
        grid-template-rows: 1fr;
        grid-template-areas: "main"
                             "aside";
        justify-items: center;
    }
}

@media screen and (min-width:900px) {
    .main{
        padding-left: 5%;
        display: grid;
        grid-template-columns: 3fr 1fr;
        grid-template-rows: 300vh;
        grid-template-areas: "main aside";
    }
}

.main{
    margin-top: 120px;
    gap: 3%;
    align-items: flex-start;
}

main{
    grid-column: main;
    width: 80%;
    justify-self: center;
}

aside{
    background-color: rgb(255, 255, 255);
    grid-column: aside;
    position: sticky;
    top: 120px;
    height: fit-content;
    width: fit-content;
    padding: 20px;
    border-radius: 10px;
}

aside h2{
    margin-bottom: 5px;
}
.profil{
    background-color: rgb(255, 255, 255);
    border-radius: 20px;
    align-items: flex-start;
}

.ban{
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-top-right-radius: 20px;
    border-top-left-radius: 20px ;
}

.profil h1{
    margin-top: 10px;
}

.info-profil{
    position: relative;
    padding: 25px;
}

.user{
    height: 75px;
    position: absolute;
    top:-50px;
    border-radius: 50%;
    border: 3px solid white;
}