:root {
    --bg: #0f1117;
    --panel: #161a24;
    --panel-2: #1b2030;
    --border: #262c3d;
    --text: #e7eaf3;
    --muted: #8b93a7;
    --accent: #4f8cff;
    --accent-soft: rgba(79, 140, 255, 0.16);
    --folder: #ffb84d;
    --file: #6ea8fe;
    --danger: #ff5d5d;
    --radius: 10px;
}

* { box-sizing: border-box; }

html, body {
    height: 100%;
    margin: 0;
}

body {
    display: flex;
    flex-direction: column;
    font-family: "Segoe UI", system-ui, sans-serif;
    font-size: 14px;
    background: var(--bg);
    color: var(--text);
}

svg { display: block; }

.topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 18px;
    border-bottom: 1px solid var(--border);
    background: var(--panel);
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    font-size: 15px;
    cursor: pointer;
    padding: 4px 8px;
    margin-left: -8px;
    border-radius: 8px;
    user-select: none;
    transition: background .13s;
}

.brand:hover { background: var(--panel-2); }
.brand:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.topbar-left {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
}

.menu-toggle { display: none; }
.menu-toggle svg { width: 20px; height: 20px; }

.brand svg { width: 20px; height: 20px; color: var(--folder); }

.toolbar { display: flex; gap: 8px; }

.btn {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 8px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--panel-2);
    color: var(--text);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: border-color .15s, background .15s, transform .1s, box-shadow .15s;
}

.btn svg { width: 16px; height: 16px; flex-shrink: 0; }
.btn:hover { border-color: var(--accent); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn:disabled,
.btn[disabled] {
    opacity: .45;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
    filter: none;
    border-color: var(--border);
}
.btn.primary {
    background: linear-gradient(180deg, #5b95ff, var(--accent));
    border-color: var(--accent);
    color: #fff;
    box-shadow: 0 2px 10px rgba(79, 140, 255, .3);
}
.btn.primary:hover { filter: brightness(1.08); box-shadow: 0 4px 14px rgba(79, 140, 255, .4); }
.btn.primary:disabled, .btn.primary[disabled] { filter: none; box-shadow: none; }
.btn:disabled:hover, .btn[disabled]:hover { filter: none; box-shadow: none; transform: none; border-color: var(--border); }
.btn.danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn.danger:hover { filter: brightness(1.1); }

.layout {
    flex: 1;
    display: flex;
    min-height: 0;
    position: relative;
}

.sidebar {
    width: 240px;
    flex-shrink: 0;
    overflow-y: auto;
    padding-bottom: 16px;
    border-right: 1px solid var(--border);
    background: var(--panel);
}

.sidebar-head {
    padding: 14px 14px 8px;
    font-size: 11px;
    letter-spacing: .08em;
    text-transform: uppercase;
    color: var(--muted);
}

#tree, #tree ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.tree-row {
    position: relative;
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 2px 6px;
    padding: 6px 8px;
    border-radius: 8px;
    cursor: pointer;
    user-select: none;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: background .13s, color .13s, box-shadow .13s;
}

.tree-row[data-depth="1"] { padding-left: 26px; }
.tree-row[data-depth="2"] { padding-left: 44px; }
.tree-row[data-depth="3"] { padding-left: 62px; }
.tree-row[data-depth="4"] { padding-left: 80px; }
.tree-row[data-depth="5"] { padding-left: 98px; }

.tree-row.sub::before {
    content: '';
    position: absolute;
    left: 12px;
    top: 0;
    bottom: 22px;
    width: 9px;
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    border-bottom-left-radius: 6px;
    pointer-events: none;
}

.tree-row.sub .tree-name {
    color: var(--muted);
}
.tree-row.sub.active .tree-name {
    color: #cfe0ff;
}

.tree-name {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
}

.tree-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    padding: 0;
    border: none;
    background: none;
    color: var(--muted);
    cursor: pointer;
    border-radius: 4px;
    margin-right: -4px;
    font-size: 15px;
    font-weight: 700;
    line-height: 1;
}
.tree-toggle.closed span { color: var(--accent); }
.tree-toggle.spacer {
    cursor: default;
    pointer-events: none;
}
.tree-toggle:hover {
    color: var(--accent);
    background: var(--panel-2);
}

.tree-actions {
    display: flex;
    gap: 2px;
    margin: -3px;
    opacity: 0;
    flex-shrink: 0;
    transition: opacity .15s;
}

.tree-row:hover .tree-actions,
.tree-row:focus-within .tree-actions {
    opacity: 1;
}

.tree-row svg { width: 16px; height: 16px; color: var(--folder); flex-shrink: 0; transition: transform .13s; }
.tree-row:hover { background: var(--panel-2); }
.tree-row:hover svg { transform: scale(1.08); }

.tree-row.active {
    background: var(--accent-soft);
    color: #cfe0ff;
    box-shadow: inset 3px 0 0 var(--accent);
    font-weight: 500;
}
.tree-row.active svg { color: var(--accent); }

.tree-actions .icon-btn svg { color: inherit; }
.tree-actions .icon-btn.rename:hover { color: var(--accent); }
.tree-actions .icon-btn.delete:hover { color: var(--danger); background: rgba(255, 93, 93, .16); }
.tree-actions .icon-btn.lock-toggle:hover { color: var(--folder); }

.tree-lock {
    display: inline-flex;
    align-items: center;
    flex-shrink: 0;
    margin-left: -4px;
}
.tree-lock svg { width: 13px; height: 13px; color: var(--folder); opacity: .85; }

.main, #main {
    flex: 1;
    min-width: 0;
    overflow-y: auto;
    padding: 14px 18px 30px;
}

.breadcrumbs, #breadcrumbs {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 2px;
    margin-bottom: 14px;
    min-height: 30px;
    font-size: 13px;
}

.crumb {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px 10px;
    border-radius: 8px;
    border: none;
    background: transparent;
    color: var(--muted);
    font-size: 13px;
    cursor: pointer;
    transition: color .13s, background .13s;
}

.crumb svg { width: 14px; height: 14px; color: var(--folder); }
.crumb:hover { color: var(--text); background: var(--panel-2); }
.crumb.current { color: var(--text); background: var(--accent-soft); font-weight: 500; cursor: default; }
.crumb-sep { color: var(--border); user-select: none; }

.items {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.empty {
    padding: 60px 0;
    text-align: center;
    color: var(--muted);
    border: 2px dashed var(--border);
    border-radius: var(--radius);
}

.upload-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    padding: 70px 16px;
}
.upload-empty .empty-hint {
    margin: 0;
    font-size: 13px;
}
.upload-empty .btn svg { width: 18px; height: 18px; }

.locked-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    padding: 70px 16px;
}
.locked-empty .locked-icon svg { width: 40px; height: 40px; color: var(--folder); }
.locked-empty .empty-hint { margin: 0; font-size: 13px; }


.item-row {
    position: relative;
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--panel);
    cursor: grab;
    user-select: none;
    transition: border-color .15s, background .15s, transform .1s;
}

.item-row:hover { border-color: #35405c; background: var(--panel-2); }
.folder-icon { display: flex; flex-shrink: 0; }
.folder-icon svg { width: 20px; height: 20px; color: var(--folder); }
.item-row.file .folder-icon svg { color: var(--file); }
.item-row.text-file { cursor: pointer; }
.item-row.text-file:hover { background: rgba(110, 168, 254, .06); }
.folder-name {
    flex: 1;
    min-width: 0;
    font-size: 13.5px;
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.folder-size { font-size: 12px; color: var(--muted); flex-shrink: 0; }
.folder-actions {
    display: flex;
    gap: 3px;
    padding: 3px;
    margin: -3px;
    border-radius: 8px;
    background: rgba(15, 17, 23, .72);
    backdrop-filter: blur(3px);
    opacity: 0;
    transform: translateY(-2px);
    transition: opacity .15s, transform .15s;
    flex-shrink: 0;
}

.item-row:hover .folder-actions, .item-row:focus-within .folder-actions {
    opacity: 1;
    transform: translateY(0);
}

.folder-actions .icon-btn.lock-toggle:hover { color: var(--folder); }

.tile-url {
    width: 180px;
    padding: 5px 8px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--panel-2);
    color: var(--muted);
    font-size: 11px;
    font-family: ui-monospace, "Cascadia Code", Consolas, monospace;
    text-overflow: ellipsis;
    cursor: pointer;
    flex-shrink: 0;
}

.tile-url:hover { color: var(--text); border-color: var(--accent); }
.tile-url:focus { outline: none; border-color: var(--accent); color: var(--text); }

.icon-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 26px;
    padding: 0;
    border: none;
    border-radius: 7px;
    background: transparent;
    color: var(--muted);
    cursor: pointer;
    transition: color .12s, background .12s, transform .1s;
}

.icon-btn svg { width: 15px; height: 15px; }
.icon-btn:hover { color: var(--text); background: rgba(255, 255, 255, .1); transform: translateY(-1px); }
.icon-btn:active { transform: translateY(0); }
.icon-btn.rename:hover { color: var(--accent); }
.icon-btn.delete:hover { color: var(--danger); background: rgba(255, 93, 93, .16); }

.dragging { opacity: .45; }

.drop-hover {
    outline: 2px dashed var(--accent);
    outline-offset: -2px;
    background: var(--accent-soft) !important;
}

.toast-stack {
    position: fixed;
    right: 18px;
    bottom: 18px;
    z-index: 200;
    display: flex;
    flex-direction: column;
    gap: 10px;
    max-width: 360px;
    pointer-events: none;
}

.toast {
    display: flex;
    align-items: center;
    gap: 10px;
    position: relative;
    padding: 12px 14px;
    overflow: hidden;
    border: 1px solid var(--border);
    border-left: 3px solid var(--accent);
    border-radius: var(--radius);
    background: linear-gradient(180deg, var(--panel-2), var(--panel));
    box-shadow: 0 10px 30px rgba(0, 0, 0, .5);
    font-size: 13px;
    line-height: 1.35;
    pointer-events: auto;
    opacity: 0;
    transform: translateX(24px) scale(.98);
    transition: opacity .28s ease, transform .28s cubic-bezier(.2, .8, .2, 1);
}

.toast.show { opacity: 1; transform: translateX(0) scale(1); }
.toast.leaving { opacity: 0; transform: translateX(24px) scale(.98); }

.toast-icon { display: flex; flex-shrink: 0; }
.toast-icon svg { width: 18px; height: 18px; }
.toast-msg { flex: 1; word-break: break-word; }

.toast-close {
    flex-shrink: 0;
    border: none;
    background: transparent;
    color: var(--muted);
    font-size: 13px;
    line-height: 1;
    cursor: pointer;
    padding: 2px 4px;
    border-radius: 6px;
}

.toast-close:hover { color: var(--text); background: rgba(255, 255, 255, .06); }

.toast-bar {
    position: absolute;
    left: 0;
    bottom: 0;
    height: 2px;
    width: 100%;
    transform-origin: left;
    background: currentColor;
    opacity: .5;
    animation: toast-bar linear forwards;
}

@keyframes toast-bar { from { transform: scaleX(1); } to { transform: scaleX(0); } }

.toast-success { border-left-color: #37c26a; }
.toast-success .toast-icon, .toast-success .toast-bar { color: #37c26a; }

.toast-error { border-left-color: var(--danger); }
.toast-error .toast-icon, .toast-error .toast-bar { color: var(--danger); }

.toast-info { border-left-color: var(--accent); }
.toast-info .toast-icon, .toast-info .toast-bar { color: var(--accent); }

.toast-progress { border-left-color: var(--accent); align-items: center; }
.toast-progress .toast-icon { color: var(--accent); }

.toast-body { flex: 1; min-width: 0; }

.progress {
    margin-top: 6px;
    height: 5px;
    border-radius: 4px;
    background: rgba(255, 255, 255, .12);
    overflow: hidden;
}

.progress-fill {
    display: block;
    height: 100%;
    width: 0;
    border-radius: 4px;
    background: var(--accent);
    transition: width .15s ease;
}

.toast-progress.indeterminate .progress-fill {
    width: 40% !important;
    animation: progress-slide 1.1s ease-in-out infinite;
}

@keyframes progress-slide {
    0% { margin-left: -40%; }
    100% { margin-left: 100%; }
}

.toast-pct {
    flex-shrink: 0;
    align-self: flex-start;
    color: var(--muted);
    font-size: 12px;
    font-variant-numeric: tabular-nums;
}

@media (prefers-reduced-motion: reduce) {
    .toast { transition: opacity .2s ease; transform: none; }
    .toast.show, .toast.leaving { transform: none; }
    .toast-bar { animation: none; display: none; }
}

.modal-overlay {
    position: fixed;
    inset: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: rgba(0, 0, 0, .55);
    backdrop-filter: blur(2px);
    opacity: 0;
    transition: opacity .18s ease;
}

.modal-overlay.show { opacity: 1; }
.modal-overlay.leaving { opacity: 0; }

.modal {
    width: 100%;
    max-width: 460px;
    padding: 18px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--panel);
    box-shadow: 0 18px 50px rgba(0, 0, 0, .55);
    transform: translateY(8px) scale(.97);
    transition: transform .2s cubic-bezier(.2, .8, .2, 1);
}

.modal-overlay.show .modal { transform: translateY(0) scale(1); }

.modal-label {
    display: block;
    margin: 4px 0 6px;
    color: var(--muted);
    font-size: 12px;
}

.modal-input {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--panel-2);
    color: var(--text);
    font-size: 14px;
}

.modal-input:focus { outline: none; border-color: var(--accent); }
.modal-input.invalid { border-color: var(--danger); animation: shake .3s; }

.modal-error {
    margin: 8px 2px 0;
    color: var(--danger);
    font-size: 12.5px;
}
.modal-error[hidden] { display: none; }

@keyframes shake {
    25% { transform: translateX(-5px); }
    50% { transform: translateX(5px); }
    75% { transform: translateX(-3px); }
}

.modal-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-weight: 600;
    font-size: 15px;
}

.modal-close { font-size: 14px; line-height: 1; }

.modal-sub {
    margin: 4px 0 12px;
    color: var(--muted);
    font-size: 13px;
    word-break: break-word;
}

.modal-url {
    width: 100%;
    padding: 9px 11px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--panel-2);
    color: var(--text);
    font-size: 13px;
    font-family: ui-monospace, "Cascadia Code", Consolas, monospace;
}

.modal-url:focus { outline: none; border-color: var(--accent); }

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    margin-top: 14px;
}

.modal-actions .btn { text-decoration: none; }

/* ---- Notepad modal ---- */

.notepad-modal { width: min(720px, 94vw); }

.notepad-file { margin-bottom: 10px; }

.notepad-area {
    width: 100%;
    min-height: 320px;
    max-height: 60vh;
    resize: vertical;
    padding: 12px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--panel-2);
    color: var(--text);
    font-family: ui-monospace, "Cascadia Code", Consolas, monospace;
    font-size: 13.5px;
    line-height: 1.55;
    tab-size: 4;
}

.notepad-area:focus { outline: none; border-color: var(--accent); }

.notepad-actions { margin-top: 12px; }
.notepad-hint { font-size: 12px; color: var(--muted); margin-right: auto; }

/* Summernote editor modal */
.summernote-modal {
    display: flex;
    flex-direction: column;
    width: min(820px, 94vw);
    max-height: 90vh;
}
.summernote-wrap {
    flex: 1 1 auto;
    min-height: 0;
    display: flex;
    flex-direction: column;
}
.summernote-wrap .note-editor {
    flex: 1 1 auto;
    min-height: 0;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    background: var(--panel);
    color: var(--text);
}
.summernote-wrap .note-editing-area {
    flex: 1 1 auto;
    min-height: 0;
    background: var(--panel-2);
}
.summernote-wrap .note-editable {
    background: var(--panel-2);
    color: var(--text);
    height: 400px;
    overflow-y: auto;
}
.summernote-wrap .note-toolbar {
    background: var(--panel-2);
    border-bottom: 1px solid var(--border);
}
.summernote-wrap .note-statusbar {
    background: var(--panel-2);
    border-top: 1px solid var(--border);
}

[hidden] { display: none !important; }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: #2a3040; border-radius: 8px; }
::-webkit-scrollbar-track { background: transparent; }

/* ---- Responsive: off-canvas sidebar drawer + compact toolbar ---- */

.sidebar-backdrop { display: none; }

@media (max-width: 768px) {
    .topbar { padding: 10px 14px; gap: 10px; }
    .menu-toggle { display: inline-flex; }

    /* Sidebar becomes an overlay drawer that slides in from the left. */
    .sidebar {
        position: absolute;
        top: 0;
        left: 0;
        bottom: 0;
        width: 260px;
        max-width: 82%;
        z-index: 40;
        transform: translateX(-100%);
        transition: transform .22s cubic-bezier(.2, .8, .2, 1);
        box-shadow: 4px 0 26px rgba(0, 0, 0, .45);
    }
    .sidebar.open { transform: translateX(0); }

    .sidebar-backdrop {
        display: block;
        position: absolute;
        inset: 0;
        z-index: 30;
        background: rgba(0, 0, 0, .5);
        opacity: 0;
        pointer-events: none;
        transition: opacity .22s ease;
    }
    .sidebar-backdrop.show { opacity: 1; pointer-events: auto; }

    .main, #main { padding: 12px 14px 24px; }
}

@media (max-width: 560px) {
    .topbar { padding: 9px 12px; }
    .toolbar { gap: 6px; }

    /* Collapse text labels — buttons become icon-only to save width. */
    .btn { padding: 9px 11px; }
    .btn span { display: none; }
}

@media (max-width: 400px) {
    .brand span { display: none; }
}