.site-header {
    position: fixed; top: 0; left: 0; width: 100%; z-index: 100;
    background-color: var(--bg-content);
    padding: 20px 0;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    transition: background-color 0.4s ease, padding 0.4s ease;
}
.site-header .container { display: flex; justify-content: space-between; align-items: center; }
.logo-text { font-family: var(--font-heading); font-size: 1.8rem; font-weight: 700; color: var(--text-light); }
.main-nav { display: none; }
.mobile-menu-button { background: none; border: none; cursor: pointer; display: flex; flex-direction: column; justify-content: space-around; width: 30px; height: 25px; z-index: 102; padding: 0; }
.mobile-menu-button span { width: 100%; height: 2px; background-color: var(--text-light); border-radius: 2px; transition: all 0.3s ease; transform-origin: center; }
.mobile-menu-button.is-active span { background-color: var(--text-light); }
.mobile-menu-button.is-active span:nth-child(1) { transform: translateY(8.5px) rotate(45deg); }
.mobile-menu-button.is-active span:nth-child(2) { opacity: 0; }
.mobile-menu-button.is-active span:nth-child(3) { transform: translateY(-8.5px) rotate(-45deg); }
.mobile-nav { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: var(--bg-dark); z-index: 101; display: flex; justify-content: center; align-items: center; transform: translateX(100%); transition: transform 0.5s cubic-bezier(0.86, 0, 0.07, 1); }
.mobile-nav.is-open { transform: translateX(0); }
.mobile-nav ul { list-style: none; text-align: center; padding: 0; }
.mobile-nav li { margin: 30px 0; }
.mobile-nav a { font-family: var(--font-heading); font-size: 2rem; color: var(--text-light); }
body.no-scroll { overflow: hidden; }

@media (min-width: 992px) {
    .site-header { background-color: transparent; padding: 30px 0; box-shadow: none; }
    .site-header.scrolled { background-color: var(--bg-content); padding: 20px 0; box-shadow: 0 5px 15px rgba(0,0,0,0.3); }
    .mobile-menu-button { display: none; }
    .main-nav { display: block; }
    .main-nav ul { list-style: none; display: flex; gap: 40px; }
    .main-nav a { font-size: 1rem; font-weight: 400; letter-spacing: 1px; position: relative; padding-bottom: 5px; }
    .main-nav a::after { content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 1px; background-color: var(--gold-primary); transition: width 0.4s cubic-bezier(0.23, 1, 0.32, 1); }
    .main-nav a:hover::after, .main-nav a.active::after { width: 100%; }
}