NAV bar spacing and search bar size

hello
what would be the correct way to change the size of the search bar
and the spacing of the right side buttons.

thanks

which file controls the search bar?

search bar: ***

@media (min-width: 992px) {
    .navbar-header .navbar-search {
        max-width: 400px; ***

button spacing: ***

@media (min-width: 992px) {
    .navbar-header {
        position: absolute;
        top: -5.5rem;
        left: 0;
        right: 0;
        margin-bottom: var(--gutter-y);
        padding-left: 0.0em;
        padding-right: 0.5em;
        --gutter-x: 6rem; ****