header {
    width: 100vw;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    padding: 1.5% 0;
    background: none;
    position: fixed;
    top: 0;
    left: 0;
    overflow: hidden;
    z-index: 999;
    /* backdrop-filter: blur(50px); */
    background: var(--color-background);
}

header a.title,
.header_responsive a.title {
    font-size: 1.6em;
    color: var(--color-primary);
    font-family: 'Relieve', sans-serif;
    font-weight: 500;
    margin-bottom: 1.5%;
    white-space: nowrap;
}

.header_responsive a.title {
    font-size: clamp(1.15em, 4vw, 1.5em);
    margin: 0;
}

.nav_links {
    list-style: none;
}

.nav_links li {
    display: inline-block;
    text-align: center;
    padding: 0 10px;
}

.nav_links li a {
    position: relative;
    padding: 0 10px;
    font-weight: 600;
    font-size: 1.15em;
    color: var(--color-noir);
    transition: color .3s;
}

.nav_links li a:not(.contactBtn):after {
    content: "";
    position: absolute;
    background-color: var(--color-primary);
    height: 3px;
    width: 100%;
    transform: scaleX(0);
    left: 0;
    bottom: -6px;
    transition: transform .3s;
    border-radius: 50px;
}

.nav_links li a:not(.contactBtn):hover:after {
    transform: scaleX(90%);
}

.nav_links li a:not(.contactBtn):hover {
    color: var(--color-primary);
}

/* btn contact */
a.contactBtn,
button.contactBtn,
.nav_links li a.contactBtn,
.row a.link {
    font-weight: 500;
    font-size: 1.1em;
    font-family: 'Relieve', sans-serif;
    padding: 12px 24px;
    background-color: var(--color-primary);
    border: var(--color-noir) 2.5px solid;
    border-radius: inherit;
    color: var(--color-blanc);
    display: flex;
    align-items: center;
    justify-content: center;
    transform: translate(-3px, -3px);
    transition: transform .15s ease-in-out;
    position: relative;
    z-index: 2;
    cursor: pointer;
}

.nav_links li a.contactBtn:hover,
button.contactBtn:hover,
a.contactBtn:hover,
.row a.link:hover {
    transform: translate(0, 0);
}

.btn {
    background-color: var(--color-noir);
    border-radius: 32px;
}

.nav_links li a.contactBtn i,
a.contactBtn i,
button.contactBtn i,
.row a.link i {
    margin-left: 8px;
    font-size: .9em;
    position: relative;
    top: 1.75px;
    transition: transform .15s ease-in-out;
}

.nav_links li a.contactBtn:hover i,
button.contactBtn:hover i,
a.contactBtn:hover i,
.row a.link:hover i {
    transform: translateX(4px);
}

/* responsive header */
.header_responsive {
    width: 100vw;
    height: 90px;
    display: none;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    padding: 0 5vw;
    background: none;
    position: fixed;
    top: 0;
    left: 0;
    overflow: none;
    z-index: 99999;
}

.menu_hamburger {
    font-size: clamp(1.5em, 6vw, 2.5em);
    color: var(--color-noir);
    display: none;
    visibility: hidden;
    cursor: pointer;
}