style.css

/*Navbar project*/
* {
    box-sizing: border-box;
}
html,body{
    height: 100%;
}
body{
    margin: 0;
    background: #f0f2f5;
}
button{
    display: grid;
    place-items: center;
    background: transparent;
    color: #606770;
    border: 0;
}
button > i {
    font-size: 20px;
}
.navbar{
    position: fixed;
    top: 0;
    left: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
    width: 100%;
    padding: 0 20px;
    border-bottom: 1px solid #e8e8e8;
    background: #fff;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}
.navbar-logo, .navbar-avatar {
    height: 40px;
    width: 40px;
    border-radius: 50%;
}
.navbar-end{
    display: flex;
    gap: 6px;
    flex: 0 0 178px;
}
.icon-button{
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #f0f2f5;
}
.navbar-badge{
    position: absolute;
    top: 8px;
    right: 54px;
    background: #e41e3f;
    color: #f9f9f9;
    font-size: 12px;
    padding: 1px 4px;
    border-radius: 10px;
}
.navbar-center{
    display: flex;
    flex: 1 1 auto;
    padding: 0 10px;
}
.navbar-center > button {
    height: 72px;
    padding-top: 4px;
    border-bottom: 4px solid transparent;
    flex:1 1 auto;
}
.navbar-center > button.active {
    border-bottom-color: #1a74e5;
}
.navbar-center > button.active > i {
    color: #1a74e5;
}
.navbar-center > button > i {
    font-size: 24px;
}
.navbar .navbar-end:last-child > button > i{
    color: #050505;
}

@media (width <= 600px){
    .navbar-end{
        flex: 0 0 auto;
    }
    .navbar-center > button{
        display: none;
    }
    .navbar-center > button:last-child {
        display: block;
        position: absolute;
        left: 110px;
        top: 50%;
        translate: 0 -50%;
    }
}
@media (width <= 400px){
    .navbar .navbar-end:last-child > button:nth-child(n+2){
        display: none;
    }
    .navbar-badge{
        right: 10px;
    }
}
@media (width <= 250px){
    .navbar .navbar-end:last-child > button:first-child{
        display: none;
    }
}