.mobile-menu-button{display:none}.nav-link{position:relative}.nav-link:after{content:"";position:absolute;bottom:0;left:0;width:0;height:2px;background-color:var(--color-primary);transition:width var(--transition)}.nav-link:hover:after{width:100%}@media(max-width:768px){.mobile-menu-button{display:block}.header-nav{display:none;position:absolute;top:100%;left:0;right:0;background-color:var(--color-surface);flex-direction:column;padding:var(--spacing-4);gap:0;border-bottom:1px solid var(--color-border)}.header-nav.open{display:flex}.nav-link{padding:var(--spacing-4);width:100%;text-align:center;border-bottom:1px solid var(--color-border)}.nav-link:last-child{border-bottom:none}}