/* ===========================================================
   nav-tree.css - Tree-style sliding drawer
   Wide viewport: drawer fills the left empty column, full viewport height
   Narrow viewport: fixed-width overlay drawer
   =========================================================== */

:root {
    /* Drawer fills exactly the empty left margin beside centered 920px container */
    --nav-drawer-width-wide: calc((100vw - 920px) / 2);
}

.nav-drawer {
    position: fixed;
    top: 66px; /* below navbar */
    left: 0;
    width: var(--nav-drawer-width-wide);
    height: calc(100vh - 66px);
    background: transparent;
    border: none;
    border-right: 1px dashed var(--border);
    z-index: 95;
    transform: translateX(-100%);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
    opacity 0.25s ease,
    visibility 0.25s ease;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
}

.nav-drawer.is-open {
    transform: translateX(0);
    opacity: 1;
    visibility: visible;
}

/* Narrow viewport - fixed overlay drawer */
@media (max-width: 1199px) {
    .nav-drawer {
        width: 280px;
        max-width: 88vw;
        background: var(--bg-page);
        box-shadow: 6px 0 20px rgba(0, 0, 0, 0.1);
    }
}

/* Invisible click-catcher (wide screens) */
.nav-drawer-overlay {
    position: fixed;
    inset: 66px 0 0 0;
    z-index: 94;
    pointer-events: none;
    background: transparent;
    transition: backdrop-filter 0.3s ease, background 0.3s ease;
}

/* Wide screens: overlay NEVER blocks content (drawer fits in empty left margin) */
@media (min-width: 1200px) {
    .nav-drawer-overlay,
    .nav-drawer-overlay.is-open {
        pointer-events: none !important;
        background: transparent;
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
    }
}

/* Narrow screens - overlay blurs and blocks content behind drawer */
@media (max-width: 1199px) {
    .nav-drawer-overlay.is-open {
        pointer-events: auto;
        background: rgba(0, 0, 0, 0.25);
        backdrop-filter: blur(6px);
        -webkit-backdrop-filter: blur(6px);
    }
}

/* Header - match breadcrumb bar height (10px padding + tag content = 52px) */
.nav-drawer-header {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    height: 52px;
    padding: 0 16px;
    box-sizing: border-box;
}

@media (max-width: 1199px) {
    .nav-drawer-header {
        border-bottom: 1px dashed var(--border);
    }
}

.nav-drawer-title {
    font-family: 'Tiro Bangla', serif;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    text-transform: uppercase;
    letter-spacing: 1.5px;
}

.nav-drawer-title-link {
    text-decoration: none;
    color: var(--text-muted);
    cursor: pointer;
    transition: color 0.2s ease;
}

.nav-drawer-title-link:hover {
    color: var(--accent);
}

.nav-drawer-actions {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    gap: 6px;
}

.nav-drawer-pin {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: color 0.2s ease, transform 0.2s ease;
    position: relative;
}

.nav-drawer-pin:hover {
    color: var(--accent);
}

.nav-drawer-pin svg {
    width: 15px;
    height: 15px;
    position: absolute;
}

.nav-drawer-pin .icon-pin-on {
    display: none;
}

.nav-drawer-pin .icon-pin-off {
    display: block;
}

.nav-drawer-pin.is-pinned {
    color: var(--accent);
    transform: rotate(45deg);
}

.nav-drawer-pin.is-pinned .icon-pin-on {
    display: block;
}

.nav-drawer-pin.is-pinned .icon-pin-off {
    display: none;
}

.nav-drawer-close {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: color 0.2s ease;
}

.nav-drawer-close:hover {
    color: var(--accent);
}

.nav-drawer-close svg {
    width: 14px;
    height: 14px;
}

/* When drawer is pinned: hide the close X (no accidental close) */
.nav-drawer.is-pinned .nav-drawer-close {
    display: none;
}

/* Body */
.nav-drawer-body {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 4px 12px 16px;
    scrollbar-width: thin;
    scrollbar-color: var(--border) transparent;
}

.nav-drawer-body::-webkit-scrollbar {
    width: 4px;
}

.nav-drawer-body::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 2px;
}

/* Tree list */
.nav-tree-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.nav-tree-list[data-depth="1"] {
    padding-left: 14px;
    margin: 0 0 0 12px;
    border-left: 1px dotted var(--border);
}

.nav-tree-list[data-depth="2"] {
    padding-left: 12px;
    margin: 0 0 0 12px;
    border-left: 1px dotted var(--border);
}

.nav-tree-item {
    list-style: none;
    margin: 0;
    padding: 0;
    border-bottom: 1px dotted var(--border);
}

.nav-tree-item:last-child {
    border-bottom: none;
}

.nav-tree-list[data-depth="1"] > .nav-tree-item,
.nav-tree-list[data-depth="2"] > .nav-tree-item {
    border-bottom: none;
}

.nav-tree-list[data-depth="1"] > .nav-tree-item + .nav-tree-item,
.nav-tree-list[data-depth="2"] > .nav-tree-item + .nav-tree-item {
    border-top: 1px dotted var(--border);
}

/* Expand-all / collapse-all icon button (home view only, beside pin/close) */
.nav-drawer-toggle-all {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: color 0.2s ease;
    position: relative;
}

.nav-drawer-toggle-all:hover {
    color: var(--accent);
}

.nav-drawer-toggle-all svg {
    width: 16px;
    height: 16px;
    position: absolute;
}

.nav-drawer-toggle-all .icon-collapse-all {
    display: none;
}

.nav-drawer-toggle-all .icon-expand-all {
    display: block;
}

.nav-drawer-toggle-all[data-open="true"] .icon-collapse-all {
    display: block;
}

.nav-drawer-toggle-all[data-open="true"] .icon-expand-all {
    display: none;
}

/* Collapsible stage row: caret toggle + navigating label */
.nav-tree-row {
    display: flex;
    align-items: center;
}

.nav-tree-row > .nav-tree-link {
    flex: 1;
    min-width: 0;
}

.nav-tree-caret {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    padding: 0;
    border: none;
    background: none;
    color: var(--text-muted);
    cursor: pointer;
    transition: transform 0.2s ease, color 0.18s ease;
}

.nav-tree-caret svg {
    width: 14px;
    height: 14px;
}

.nav-tree-caret:hover {
    color: var(--accent);
}

.nav-tree-collapsible.is-expanded > .nav-tree-row > .nav-tree-caret {
    transform: rotate(90deg);
}

/* Sessions stay in the DOM; collapse state controls visibility */
.nav-tree-collapsible > .nav-tree-list {
    display: none;
}

.nav-tree-collapsible.is-expanded > .nav-tree-list {
    display: block;
}

.nav-tree-link {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 6px;
    color: var(--text-main);
    text-decoration: none;
    font-size: 0.9rem;
    font-family: 'Hind Siliguri', sans-serif;
    transition: color 0.18s ease, transform 0.18s ease;
    position: relative;
}

.nav-tree-link:hover:not(.is-disabled) {
    color: var(--accent);
    transform: translateX(3px);
}

.nav-tree-link.is-disabled {
    cursor: not-allowed;
    opacity: 0.5;
    color: var(--text-muted);
}

/* Current page highlight - left accent bar + warm gradient */
.nav-tree-link.is-current {
    color: var(--highlight);
    font-weight: 600;
    border: none;
    border-left: 2.5px solid var(--highlight);
    border-radius: 0 6px 6px 0;
    padding: 10px 6px;
    background: linear-gradient(90deg, rgba(201, 123, 60, 0.12) 0%, transparent 80%);
}

[data-theme="dark"] .nav-tree-link.is-current {
    color: var(--highlight);
    background: linear-gradient(90deg, rgba(232, 155, 92, 0.1) 0%, transparent 80%);
}

.nav-tree-link.is-current .nav-tree-bullet {
    background: var(--highlight);
    opacity: 1;
    transform: scale(1.3);
}

.nav-tree-link.is-current:hover {
    transform: none;
}

/* Drawer title highlight when at current page */
.nav-drawer-title.is-current {
    color: var(--highlight);
    border-bottom: none;
    padding-bottom: 0;
    border-left: 2.5px solid var(--highlight);
    padding-left: 9px;
    background: linear-gradient(90deg, rgba(201, 123, 60, 0.12) 0%, transparent 80%);
    border-radius: 0 3px 3px 0;
}

[data-theme="dark"] .nav-drawer-title.is-current {
    color: var(--highlight);
    background: linear-gradient(90deg, rgba(232, 155, 92, 0.1) 0%, transparent 80%);
}

.nav-tree-bullet {
    flex-shrink: 0;
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--highlight);
    opacity: 0.6;
}

.nav-tree-link.is-disabled .nav-tree-bullet {
    background: var(--text-muted);
    opacity: 0.35;
}

.nav-tree-link:hover:not(.is-disabled) .nav-tree-bullet {
    opacity: 1;
    transform: scale(1.3);
}

.nav-tree-label {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    line-height: 1.35;
}

.nav-tree-badge {
    flex-shrink: 0;
    font-size: 0.58rem;
    padding: 1px 6px;
    border-radius: 100px;
    background: transparent;
    border: 1px dashed var(--border);
    color: var(--text-muted);
    font-family: 'Hind Siliguri', sans-serif;
    white-space: nowrap;
}

.nav-tree-empty {
    padding: 14px 6px;
    font-size: 0.85rem;
    color: var(--text-muted);
    font-style: italic;
}

/* Breadcrumb buttons */
.breadcrumb [data-nav-tree] {
    background: none;
    border: none;
    padding: 0;
    font: inherit;
    color: inherit;
    cursor: pointer;
    text-decoration: none;
    transition: color 0.2s ease;
    font-family: inherit;
}

.breadcrumb [data-nav-tree]:hover {
    color: var(--accent);
}

/* Small screens */
@media (max-width: 768px) {
    .nav-drawer {
        top: 60px;
    }

    .nav-drawer-overlay {
        inset: 60px 0 0 0;
    }
}