header {
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    background-color: #ffffff85;
    backdrop-filter: blur(10px);
}

.hamburger .lines,
.hamburger .lines:before,
.hamburger .lines:after {
    background: black;
}

header .def-btn {
    background: black;
    border-color: black;
    color: white;
}