/* Sticky Header Navigation */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-height);
    background-color: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-zinc-200);
    display: flex;
    align-items: center;
    transition: all var(--transition-normal);
}

.header-container {
    width: 100%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Brand Logo Layout */
.site-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
}

.logo-image {
    max-height: 2.25rem;
    width: auto;
    border-radius: var(--border-radius-sm);
    object-fit: contain;
    transition: transform var(--transition-fast);
}

.site-logo:hover .logo-image {
    transform: scale(1.05);
}

.logo-icon-large {
    width: 2.25rem;
    height: 2.25rem;
    background-color: var(--color-brand-50);
    border: 1px solid var(--color-brand-100);
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-brand-800);
}

.logo-text {
    font-family: var(--font-body);
    font-weight: 700;
    font-size: 1.15rem;
    letter-spacing: -0.03em;
    color: var(--color-zinc-900);
    text-transform: uppercase;
}

.logo-subtext {
    font-weight: 300;
    color: var(--color-brand-800);
}

/* Nav Menu Items */
.desktop-nav {
    display: flex;
    align-items: center;
    gap: 1.75rem;
}

@media (max-width: 768px) {
    .desktop-nav {
        display: none;
    }
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-zinc-500);
    position: relative;
    padding: 0.25rem 0;
}

.nav-link:hover {
    color: var(--color-brand-800);
}

.nav-link.active {
    color: var(--color-brand-800);
    font-weight: 600;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--color-brand-800);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform var(--transition-normal);
}

.nav-link:hover::after,
.nav-link.active::after {
    transform: scaleX(1);
    transform-origin: left;
}

.btn-logout {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: #ef4444;
    background: transparent;
    padding: 0.35rem 0.75rem;
    border-radius: var(--border-radius-sm);
    border: 1px solid rgba(239, 68, 68, 0.15);
}

.btn-logout:hover {
    background-color: rgba(239, 68, 68, 0.05);
}

/* Mobile Hamburger Menu */
.mobile-menu-button {
    display: none;
    padding: 0.5rem;
    color: var(--color-zinc-600);
    cursor: pointer;
    border-radius: var(--border-radius-sm);
}

.mobile-menu-button:hover {
    background-color: var(--color-zinc-100);
}

@media (max-width: 768px) {
    .mobile-menu-button {
        display: flex;
        align-items: center;
    }
}

/* Mobile Drawer */
.mobile-menu-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(24, 24, 27, 0.3);
    backdrop-filter: blur(4px);
    z-index: 900;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-normal);
}

.mobile-menu-content {
    position: fixed;
    top: 0;
    bottom: 0;
    right: 0;
    width: 18rem;
    background-color: white;
    z-index: 1000;
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    box-shadow: -10px 0 30px -10px rgba(0, 0, 0, 0.15);
    display: flex;
    flex-direction: column;
    padding: 1.5rem;
}

#mobile-menu-toggle:checked ~ .mobile-menu-overlay {
    opacity: 1;
    pointer-events: auto;
}

#mobile-menu-toggle:checked ~ .mobile-menu-content {
    transform: translateX(0);
}

.mobile-menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--color-zinc-100);
    padding-bottom: 1rem;
    margin-bottom: 1.5rem;
}

.mobile-menu-close {
    padding: 0.35rem;
    color: var(--color-zinc-400);
    cursor: pointer;
}

.mobile-menu-close:hover {
    color: var(--color-zinc-900);
}

.mobile-nav {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.mobile-nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius-sm);
    color: var(--color-zinc-600);
    font-weight: 500;
}

.mobile-nav-item:hover {
    background-color: var(--color-zinc-100);
    color: var(--color-zinc-900);
}

.mobile-nav-item.active {
    background-color: var(--color-brand-50);
    color: var(--color-brand-800);
    font-weight: 600;
}

/* Core Container Setup */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.content-container {
    flex: 1;
    width: 100%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 2.5rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

@media (max-width: 640px) {
    .content-container {
        padding: 1.5rem 1rem;
    }
}

/* Institutional Footer */
.main-footer {
    margin-top: auto;
    padding-top: 2rem;
    border-top: 1px solid var(--color-zinc-200);
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 1.5rem;
    font-size: 0.85rem;
}

.footer-left {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.footer-brand {
    font-weight: 700;
    color: var(--color-zinc-900);
}

.footer-copyright {
    color: var(--color-zinc-400);
}

.footer-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.footer-link {
    color: var(--color-zinc-500);
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.footer-link:hover {
    color: var(--color-brand-800);
}

@media (max-width: 640px) {
    .main-footer {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .footer-links {
        flex-wrap: wrap;
        gap: 1rem;
    }
}