/* ============================================
   VARTA Systems — Shared Navigation & Layout
   ============================================ */

/* --- Global Nav Bar --- */
.varta-nav {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 32px;
    background: hsl(var(--background) / 0.92);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid hsl(var(--border));
    font-family: var(--font-heading);
}

.varta-nav .nav-brand {
    font-weight: 700;
    font-size: 15px;
    letter-spacing: 0.06em;
    color: hsl(var(--foreground));
    text-decoration: none;
}
.varta-nav .nav-brand:hover {
    text-decoration: none;
    color: hsl(var(--primary));
}

.varta-nav .nav-links {
    display: flex;
    gap: 28px;
    font-size: 14px;
    font-weight: 500;
    align-items: center;
}

.varta-nav .nav-links a {
    color: hsl(var(--muted-foreground));
    text-decoration: none;
    transition: color 0.15s ease;
    position: relative;
}
.varta-nav .nav-links a:hover {
    color: hsl(var(--foreground));
    text-decoration: none;
}
.varta-nav .nav-links a[aria-current="page"] {
    color: hsl(var(--primary));
}
.varta-nav .nav-links a[aria-current="page"]::after {
    content: '';
    position: absolute;
    bottom: -14px;
    left: 0;
    right: 0;
    height: 2px;
    background: hsl(var(--primary));
    border-radius: 1px;
}

/* Hamburger toggle (hidden on desktop) */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    color: hsl(var(--foreground));
}
.nav-toggle svg {
    width: 22px;
    height: 22px;
}

/* --- Breadcrumbs --- */
.breadcrumbs {
    font-family: var(--font-mono);
    font-size: 12px;
    color: hsl(var(--muted-foreground));
    padding: 10px 32px;
    display: flex;
    gap: 8px;
    align-items: center;
    border-bottom: 1px solid hsl(var(--border) / 0.5);
}
.breadcrumbs a {
    color: hsl(var(--primary));
    text-decoration: none;
}
.breadcrumbs a:hover {
    text-decoration: underline;
}
.breadcrumbs .sep {
    opacity: 0.35;
    font-size: 10px;
}

/* --- Docs Sidebar Layout --- */
.docs-layout {
    display: grid;
    grid-template-columns: 240px 1fr;
    gap: 0;
    min-height: calc(100vh - 60px);
}

.docs-sidebar {
    position: sticky;
    top: 52px;
    height: calc(100vh - 52px);
    overflow-y: auto;
    padding: 24px 20px 40px 32px;
    border-right: 1px solid hsl(var(--border));
    font-size: 13px;
    scrollbar-width: thin;
    scrollbar-color: hsl(var(--border)) transparent;
}
.docs-sidebar::-webkit-scrollbar {
    width: 4px;
}
.docs-sidebar::-webkit-scrollbar-thumb {
    background: hsl(var(--border));
    border-radius: 2px;
}

.sidebar-section {
    margin-bottom: 20px;
}
.sidebar-label {
    font-family: var(--font-mono);
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: hsl(var(--muted-foreground));
    margin-bottom: 8px;
    font-weight: 600;
}
.sidebar-link {
    display: block;
    padding: 5px 10px;
    margin: 1px 0;
    color: hsl(var(--muted-foreground));
    text-decoration: none;
    border-radius: 6px;
    font-size: 13px;
    line-height: 1.4;
    transition: color 0.12s, background 0.12s;
}
.sidebar-link:hover {
    color: hsl(var(--foreground));
    background: hsl(var(--primary) / 0.06);
    text-decoration: none;
}
.sidebar-link.active {
    color: hsl(var(--primary));
    background: hsl(var(--primary) / 0.1);
    font-weight: 500;
}
.sidebar-link.external::after {
    content: ' \2192';
    opacity: 0.5;
    font-size: 11px;
}

.docs-content {
    padding: 32px 40px 80px;
    max-width: 920px;
    min-width: 0;
}

/* --- Collapsible Sections --- */
details.collapsible {
    margin: 16px 0;
    border: 1px solid hsl(var(--border));
    border-radius: 12px;
    overflow: hidden;
}
details.collapsible summary {
    padding: 16px 20px;
    cursor: pointer;
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 600;
    color: hsl(var(--foreground));
    background: hsl(var(--card));
    list-style: none;
    display: flex;
    align-items: center;
    gap: 10px;
}
details.collapsible summary::-webkit-details-marker {
    display: none;
}
details.collapsible summary::before {
    content: '\25B6';
    font-size: 10px;
    color: hsl(var(--muted-foreground));
    transition: transform 0.2s;
}
details.collapsible[open] summary::before {
    transform: rotate(90deg);
}
details.collapsible .detail-body {
    padding: 20px;
}

/* --- Responsive --- */
@media (max-width: 900px) {
    .docs-layout {
        grid-template-columns: 1fr;
    }
    .docs-sidebar {
        position: static;
        height: auto;
        border-right: none;
        border-bottom: 1px solid hsl(var(--border));
        padding: 16px 20px;
        display: flex;
        flex-wrap: wrap;
        gap: 4px 16px;
    }
    .sidebar-section {
        margin-bottom: 8px;
    }
    .sidebar-label {
        width: 100%;
        margin-bottom: 4px;
    }
    .docs-content {
        padding: 24px 20px 60px;
    }
}

@media (max-width: 640px) {
    .varta-nav {
        padding: 12px 16px;
    }
    .varta-nav .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: hsl(var(--background));
        border-bottom: 1px solid hsl(var(--border));
        flex-direction: column;
        gap: 0;
        padding: 8px 0;
    }
    .varta-nav .nav-links.open {
        display: flex;
    }
    .varta-nav .nav-links a {
        padding: 12px 24px;
        border-bottom: 1px solid hsl(var(--border) / 0.3);
    }
    .varta-nav .nav-links a[aria-current="page"]::after {
        display: none;
    }
    .nav-toggle {
        display: block;
    }
    .breadcrumbs {
        padding: 8px 16px;
        font-size: 11px;
    }
}