.site-header{background:var(--bg-secondary);border-bottom:1px solid var(--border-primary);position:-webkit-sticky;position:sticky;top:0;z-index:100}.header-content{max-width:1200px;margin:0 auto;padding:var(--space-md) var(--space-xl);display:flex;justify-content:space-between;align-items:center}.logo a{font-size:var(--font-size-xl);font-weight:700;color:var(--accent-primary);text-decoration:none;font-family:var(--font-header)}.nav-actions{gap:var(--space-md)}.nav-actions,.nav-links{display:flex;align-items:center}.nav-links{gap:var(--space-lg);margin-right:var(--space-md)}.nav-link{color:var(--text-secondary);text-decoration:none;padding:var(--space-sm) var(--space-md);border-radius:var(--radius-sm);font-weight:500;transition:all .2s ease}.nav-link:hover{color:var(--accent-primary);background:var(--bg-tertiary)}.user-menu{gap:var(--space-md)}.user-menu,.user-profile{display:flex;align-items:center}.user-profile{gap:var(--space-sm);text-decoration:none;color:var(--text-secondary);padding:var(--space-sm);border-radius:var(--radius-sm);transition:all .2s ease}.user-profile:hover{color:var(--text-primary);background:var(--bg-tertiary)}.profile-image{object-fit:cover}.profile-image,.profile-sketch-avatar{width:32px;height:32px;border-radius:var(--radius-sm);border:1px solid var(--border-primary)}.profile-sketch-avatar{overflow:hidden;display:flex;align-items:center;justify-content:center}.profile-sketch-avatar svg{width:100%;height:100%;object-fit:cover}.profile-default-avatar{width:32px;height:32px;background:var(--accent-primary);color:#fff;font-weight:700;font-size:14px}.profile-default-avatar,.settings-link{border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center}.settings-link{color:var(--text-secondary);padding:var(--space-sm);transition:all .2s ease}.settings-link:hover{color:var(--accent-primary);background:var(--bg-tertiary)}.loading-auth{color:var(--text-muted);font-size:var(--font-size-sm)}@media(max-width:768px){.header-content{padding:var(--space-sm) var(--space-md);flex-wrap:wrap;gap:var(--space-sm)}.nav-links{display:none}.user-menu{gap:var(--space-sm)}}.loading-auth-skeleton{display:flex;align-items:center;gap:var(--space-md)}.skeleton{background:var(--bg-tertiary);border-radius:var(--radius-sm);animation:skeleton-pulse 1.5s ease-in-out infinite}.skeleton-avatar{width:32px;height:32px}.skeleton-username{width:100px;height:14px}.skeleton-button{width:80px;height:32px}@keyframes skeleton-pulse{0%{opacity:1}50%{opacity:.4}to{opacity:1}}.container{max-width:1200px;margin:0 auto;padding:0 var(--space-lg)}.container-sm{max-width:640px}.container-md{max-width:768px}.container-lg{max-width:1024px}.container-xl{max-width:1280px}.main-layout,.page-layout{min-height:100vh;display:flex;flex-direction:column;background:var(--bg-primary)}.main-content{flex:1 1;padding:var(--space-xl) 0}