/* =============================================
   HEADER
============================================= */
header{position:fixed;top:0;left:0;right:0;z-index:100;display:flex;justify-content:space-between;align-items:center;height:var(--header-h);padding:0 2rem;background:rgba(250,248,245,.85);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border-bottom:1px solid rgba(88,129,87,.08);transition:background .4s,box-shadow .3s,height .3s}
header.scrolled{background:rgba(250,248,245,.96);box-shadow:0 2px 16px rgba(0,0,0,.05);height:58px}
[data-theme="dark"] header{background:rgba(20,26,20,.85)}
[data-theme="dark"] header.scrolled{background:rgba(20,26,20,.96)}

/* LOGO */
#logo,#logo a{display:flex;align-items:center;gap:.5rem;height:100%;text-decoration:none}
#logo img{height:40px;width:40px;border-radius:50%;object-fit:cover;transition:height .3s,width .3s}
header.scrolled #logo img{height:34px;width:34px}
.site-title{font-family:var(--font-heading);font-weight:600;font-size:1.1rem;color:var(--heading);white-space:nowrap;transition:font-size .3s}
header.scrolled .site-title{font-size:1rem}

/* NAV */
#menu{display:flex;align-items:center;gap:.15rem}
.menu-link{padding:.4rem .8rem;font-size:.85rem;font-weight:500;color:var(--text-muted);text-decoration:none;border-radius:8px;transition:color .2s,background .2s}
.menu-link:hover,.menu-link:focus,.menu-link.active-link{color:var(--green-700);background:var(--green-50)}
[data-theme="dark"] .menu-link.active-link{background:var(--green-100)}

/* HEADER ACTIONS */
.header-actions{display:flex;align-items:center;gap:.4rem}
.icon-btn{background:none;border:1px solid var(--card-border);width:36px;height:36px;border-radius:50%;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s;color:var(--text);font-family:var(--font-body);position:relative}
.icon-btn:hover{background:var(--green-50);border-color:var(--green-200)}
.lang-label{font-size:.72rem;font-weight:700;letter-spacing:.5px}
.theme-icon{width:18px;height:18px;position:absolute;transition:opacity .3s,transform .3s}
.theme-icon--dark{opacity:1;transform:rotate(0)}
.theme-icon--light{opacity:0;transform:rotate(90deg)}
[data-theme="dark"] .theme-icon--dark{opacity:0;transform:rotate(-90deg)}
[data-theme="dark"] .theme-icon--light{opacity:1;transform:rotate(0)}

/* HAMBURGER */
.menu-toggle{display:none;background:none;border:none;cursor:pointer;width:36px;height:36px;position:relative;padding:0}
.hamburger,.hamburger::before,.hamburger::after{display:block;width:20px;height:2px;background:var(--text);border-radius:2px;position:absolute;left:50%;transform:translateX(-50%);transition:all .3s ease}
.hamburger{top:50%;margin-top:-1px}
.hamburger::before{content:'';top:-6px}
.hamburger::after{content:'';top:6px}
.menu-toggle[aria-expanded="true"] .hamburger{background:transparent}
.menu-toggle[aria-expanded="true"] .hamburger::before{top:0;transform:translateX(-50%) rotate(45deg)}
.menu-toggle[aria-expanded="true"] .hamburger::after{top:0;transform:translateX(-50%) rotate(-45deg)}

/* RESPONSIVE */
@media(max-width:900px){
    header{padding:0 1rem}
    .menu-toggle{display:flex;align-items:center;justify-content:center}
    #menu{position:fixed;top:var(--header-h);left:0;right:0;flex-direction:column;background:rgba(250,248,245,.97);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);padding:.75rem;gap:.15rem;border-bottom:1px solid var(--card-border);box-shadow:0 8px 20px rgba(0,0,0,.06);transform:translateY(-120%);opacity:0;visibility:hidden;transition:transform .35s ease,opacity .35s,visibility .35s}
    [data-theme="dark"] #menu{background:rgba(20,26,20,.97)}
    #menu.open{transform:translateY(0);opacity:1;visibility:visible}
    .menu-link{width:100%;text-align:center;padding:.65rem;font-size:.95rem}
}