/* ============================================
   Layout — Mobile-first Responsive Grid
   ============================================ */

/* --- Page wrapper --- */

.page-wrapper {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* --- Site header (sticky) --- */

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-height);
}

/* --- Content area (sidebar + main) --- */

.content-wrapper {
    display: flex;
    flex: 1;
    margin-top: 0;
}

/* --- Sidebar --- */

.sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    bottom: 0;
    width: var(--sidebar-width);
    z-index: 90;
    overflow-y: auto;
    transform: translateX(-100%);
    transition: transform var(--transition-normal);
}

.sidebar.open {
    transform: translateX(0);
}

/* --- Sidebar overlay (mobile) --- */

.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    top: var(--header-height);
    background: var(--color-overlay);
    z-index: 80;
}

.sidebar-overlay.visible {
    display: block;
}

/* --- Main content --- */

.main-content {
    flex: 1;
    width: 100%;
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: var(--space-lg) var(--space-md);
}

/* --- Footer --- */

.site-footer {
    margin-top: auto;
}

/* ============================================
   Tablet+ breakpoint (≥ 768px)
   Two-column: sidebar visible + fluid main
   ============================================ */

@media (min-width: 768px) {
    .sidebar {
        position: fixed;
        transform: translateX(0);
    }

    .content-wrapper {
        margin-left: var(--sidebar-width);
    }

    .sidebar-overlay {
        display: none !important;
    }

    .hamburger {
        display: none !important;
    }

    .main-content {
        padding: var(--space-xl) var(--space-2xl);
    }
}

/* ============================================
   Large desktop (≥ 1200px)
   ============================================ */

@media (min-width: 1200px) {
    .main-content {
        padding: var(--space-2xl) var(--space-3xl);
    }
}