/* ============================================
   Admin Panel - Unified Theme & Style
   ============================================ */

/* --- CSS Variables (theme) --- */
:root {
    --admin-card-border: #dee2e6;
    --admin-card-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    --admin-header-bg: #f8f9fa;
    --admin-table-hover: #f8f9fa;
    --admin-filter-header-bg: #f8f9fa;
    --admin-modal-radius: 0.375rem;
    --admin-thumb-size: 56px;
    --admin-thumb-radius: 4px;
    --admin-ease: cubic-bezier(0.22, 1, 0.36, 1);
    --admin-anim-duration: 360ms;
}

/* --- Smooth in-page scroll for hash links and JS scrollTo --- */
html {
    scroll-behavior: smooth;
}

/* --- Page-load entrance animation --------------------------------------
 * The main content fades + slides in once. Cards/sections stagger slightly
 * after, giving a "modern app" feel without adding JS dependencies.
 * Honors prefers-reduced-motion.
 */
/* Final keyframe uses transform: none so we do not leave a transform-containing
 * block on the main shell; that would trap Bootstrap modals and let in-flow controls
 * (e.g. table action buttons) paint above the fixed dialog. */
@keyframes adminFadeUp {
    from { opacity: 0; transform: translate3d(0, 8px, 0); }
    to   { opacity: 1; transform: none; }
}

@keyframes adminFadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* The container Bootstrap renders right after the navbar. */
body > .container-fluid,
body > .container,
.admin-page-enter {
    animation: adminFadeUp var(--admin-anim-duration) var(--admin-ease) both;
    /* Avoid will-change: transform — it keeps a stacking/containing context that breaks fixed modals. */
    will-change: opacity;
}

/* Top-level cards/sections inside the main container stagger in slightly. */
body > .container-fluid > .card,
body > .container-fluid > .row,
body > .container-fluid > .admin-page-header,
body > .container-fluid > .d-flex {
    animation: adminFadeUp var(--admin-anim-duration) var(--admin-ease) both;
    animation-delay: 60ms;
}
body > .container-fluid > *:nth-child(2) { animation-delay: 120ms; }
body > .container-fluid > *:nth-child(3) { animation-delay: 180ms; }
body > .container-fluid > *:nth-child(4) { animation-delay: 240ms; }
body > .container-fluid > *:nth-child(n+5) { animation-delay: 300ms; }

/* Top navigation slides down a tick. */
body > .navbar {
    /* Lift the navbar above in-flow content. During the short entrance animation,
       nested blocks may still use transform; without this, focused controls could
       paint above the user dropdown. */
    position: relative;
    z-index: 1030;
    animation: adminFadeIn 220ms var(--admin-ease) both;
}

/* Make the user dropdown sit above any animated content that follows it. */
.navbar-nav .dropdown-menu.show {
    z-index: 1031;
}

/* --- Top loading progress bar (NProgress-style, no library) ----------- */
#admin-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    width: 0%;
    z-index: 2000;
    background: linear-gradient(90deg, #2563eb 0%, #06b6d4 50%, #16a34a 100%);
    box-shadow: 0 0 10px rgba(37, 99, 235, 0.45);
    border-radius: 0 2px 2px 0;
    transition: width 240ms var(--admin-ease), opacity 200ms ease 200ms;
    opacity: 0;
    pointer-events: none;
}
#admin-progress.is-active { opacity: 1; }
#admin-progress.is-finishing { width: 100% !important; }

/* --- Body fade-out right before navigating away to a new admin page --- */
body.is-leaving > .container-fluid,
body.is-leaving > .container {
    transition: opacity 160ms ease, transform 160ms ease;
    opacity: 0;
    transform: translate3d(0, -4px, 0);
}

/* --- Card hover micro-interaction (subtle, modern) ------------------- */
.admin-list-card,
.admin-form-card,
.admin-filter-card {
    transition: box-shadow 200ms var(--admin-ease), transform 200ms var(--admin-ease);
}
.admin-list-card:hover,
.admin-form-card:focus-within {
    box-shadow: 0 0.4rem 1rem rgba(15, 23, 42, 0.07);
}

/* --- Buttons: gentle press feedback ---------------------------------- */
.btn {
    transition: transform 120ms var(--admin-ease), box-shadow 120ms var(--admin-ease), background-color 120ms ease, border-color 120ms ease, color 120ms ease;
}
.btn:not(:disabled):active {
    transform: translateY(1px);
}

/* --- Form controls: smoother focus ring ------------------------------ */
.form-control,
.form-select {
    transition: border-color 160ms var(--admin-ease), box-shadow 160ms var(--admin-ease);
}

/* --- Respect users who don't want motion ----------------------------- */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    body > .container-fluid,
    body > .container,
    body > .container-fluid > .card,
    body > .container-fluid > .row,
    body > .container-fluid > .admin-page-header,
    body > .container-fluid > .d-flex,
    body > .navbar,
    .admin-page-enter {
        animation: none !important;
    }
    body.is-leaving > .container-fluid,
    body.is-leaving > .container {
        transition: none;
        opacity: 1;
        transform: none;
    }
    #admin-progress {
        transition: opacity 100ms ease;
    }
}

/* --- Page header (consistent across pages) --- */
.admin-page-header {
    border-bottom: 1px solid var(--admin-card-border);
    padding-bottom: 0.75rem;
    margin-bottom: 1.5rem;
}

/* --- Filter / Search box (same style on all list pages) --- */
.admin-filter-card {
    background: #fff;
    border: 1px solid var(--admin-card-border);
    border-radius: var(--admin-modal-radius);
    box-shadow: var(--admin-card-shadow);
    margin-bottom: 1.5rem;
}

.admin-filter-card .card-header {
    background: var(--admin-filter-header-bg);
    border-bottom: 1px solid var(--admin-card-border);
    padding: 0.5rem 1rem;
    font-weight: 600;
    font-size: 0.9rem;
}

.admin-filter-card .card-body {
    padding: 1rem;
}

.admin-filter-card .card-body .row {
    min-width: 0;
}

/* --- Main content card (list/table container) --- */
.admin-list-card {
    background: #fff;
    border: 1px solid var(--admin-card-border);
    border-radius: var(--admin-modal-radius);
    box-shadow: var(--admin-card-shadow);
}

.admin-list-card .card-body {
    padding: 1rem;
}

/* --- Tables (same look everywhere) --- */
.admin-table,
.table.admin-table {
    margin-bottom: 0;
}

.admin-table thead th,
.table.admin-table thead th {
    background: var(--admin-header-bg) !important;
    border-bottom: 1px solid var(--admin-card-border);
    font-weight: 600;
    font-size: 0.875rem;
    padding: 0.6rem 0.75rem;
}

.admin-table tbody td,
.table.admin-table tbody td {
    padding: 0.6rem 0.75rem;
    font-size: 0.875rem;
    vertical-align: middle;
}

.admin-table tbody tr:hover,
.table.admin-table tbody tr:hover {
    background-color: var(--admin-table-hover);
}

/* --- Action buttons (consistent size and spacing) --- */
.admin-list-card .btn-sm,
.admin-filter-card .btn-sm {
    font-size: 0.8125rem;
}

.admin-list-card .btn-group .btn,
.admin-list-card .d-flex.gap-1 .btn {
    margin: 0 1px;
}

/* --- Mobile list cards (same style) --- */
.admin-mobile-card {
    border: 1px solid var(--admin-card-border);
    border-radius: var(--admin-modal-radius);
    margin-bottom: 0.75rem;
    box-shadow: var(--admin-card-shadow);
}

.admin-mobile-card .card-body {
    padding: 0.75rem 1rem;
}

/* Mobile: strict thumbnail box so image never fills screen */
.admin-mobile-thumb-wrap {
    width: var(--admin-thumb-size);
    height: var(--admin-thumb-size);
    min-width: var(--admin-thumb-size);
    max-width: var(--admin-thumb-size);
    flex-shrink: 0;
    overflow: hidden;
    border-radius: var(--admin-thumb-radius);
    border: 1px solid var(--admin-card-border);
}

.admin-mobile-thumb-wrap .admin-thumb,
.admin-mobile-thumb-wrap img {
    width: var(--admin-thumb-size) !important;
    height: var(--admin-thumb-size) !important;
    max-width: var(--admin-thumb-size) !important;
    max-height: var(--admin-thumb-size) !important;
    object-fit: cover;
    display: block;
}

.admin-mobile-thumb-wrap .admin-thumb-placeholder {
    width: 100%;
    height: 100%;
    box-sizing: border-box;
}

/* --- Thumbnail images (same size/radius everywhere) --- */
.admin-thumb {
    width: var(--admin-thumb-size);
    height: var(--admin-thumb-size);
    max-width: var(--admin-thumb-size) !important;
    max-height: var(--admin-thumb-size) !important;
    object-fit: cover;
    border-radius: var(--admin-thumb-radius);
    border: 1px solid var(--admin-card-border);
    display: block;
}

/* Table cell that contains only a thumbnail - prevents image from stretching table */
.admin-table td.admin-thumb-cell,
.admin-list-card .admin-thumb-wrap {
    width: 1%;
    white-space: nowrap;
    vertical-align: middle;
}

.admin-table td.admin-thumb-cell .admin-thumb,
.admin-list-card .admin-thumb-wrap .admin-thumb {
    width: var(--admin-thumb-size);
    height: var(--admin-thumb-size);
    max-width: var(--admin-thumb-size) !important;
    max-height: var(--admin-thumb-size) !important;
}

.admin-thumb-placeholder {
    width: var(--admin-thumb-size);
    height: var(--admin-thumb-size);
    border-radius: var(--admin-thumb-radius);
    background: var(--admin-header-bg);
    border: 1px solid var(--admin-card-border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    color: #6c757d;
}

/* --- Modals (same style) --- */
/* After admin.js moves .modal.admin-modal to body, keep stack above toasts (1090) and
 * other admin chrome so the dimmer covers the full viewport (no bright “strip” on the right). */
.modal.admin-modal {
    z-index: 12000;
}

body > .modal-backdrop {
    z-index: 11990;
}

.admin-modal .modal-content {
    border: 1px solid var(--admin-card-border);
    border-radius: var(--admin-modal-radius);
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

.admin-modal .modal-header {
    background: var(--admin-header-bg);
    border-bottom: 1px solid var(--admin-card-border);
    padding: 0.75rem 1rem;
    font-weight: 600;
    font-size: 0.95rem;
}

.admin-modal .modal-body {
    padding: 1rem;
}

.admin-modal .modal-footer {
    border-top: 1px solid var(--admin-card-border);
    padding: 0.75rem 1rem;
}

.admin-modal .modal-footer .btn {
    font-size: 0.875rem;
}

/* --- Form cards (create/edit pages) --- */
.admin-form-card {
    border: 1px solid var(--admin-card-border);
    border-radius: var(--admin-modal-radius);
    box-shadow: var(--admin-card-shadow);
}

.admin-form-card .card-header {
    background: var(--admin-filter-header-bg);
    border-bottom: 1px solid var(--admin-card-border);
    padding: 0.5rem 1rem;
    font-weight: 600;
    font-size: 0.9rem;
}

.admin-form-card .card-body {
    padding: 1rem;
}

/* --- Badges (consistent) --- */
.admin-list-card .badge {
    font-size: 0.75rem;
}

/* ============================================
   Existing nav styles (keep)
   ============================================ */

.navbar-nav .nav-link.active {
    background-color: rgba(255, 255, 255, 0.2);
    font-weight: 600;
    border-bottom: 2px solid rgba(255, 255, 255, 0.8);
}

.navbar-nav .nav-link.active:hover {
    background-color: rgba(255, 255, 255, 0.25);
}

.navbar-nav .dropdown-menu {
    right: 0;
    left: auto;
    min-width: 180px;
}

@media (max-width: 991px) {
    .navbar-nav .dropdown-menu {
        position: static !important;
        float: none;
        width: 100%;
        margin-top: 0;
        background-color: rgba(255, 255, 255, 0.1);
        border: 0;
        box-shadow: none;
    }
}

/* ============================================
   Mobile / small-tablet “app shell” (≤767px)
   ============================================ */
.classtoper-admin .navbar.sticky-top {
    padding-top: max(0.35rem, env(safe-area-inset-top, 0px));
}

.classtoper-admin .navbar-brand {
    min-width: 0;
    max-width: calc(100% - 3.25rem);
}

.classtoper-admin .navbar-brand .navbar-brand-text {
    min-width: 0;
}

.classtoper-admin .admin-navbar-logo {
    height: 2rem;
    width: auto;
    max-width: 7.5rem;
    object-fit: contain;
    display: block;
    background: rgba(255, 255, 255, 0.96);
    border-radius: 0.375rem;
    padding: 0.125rem 0.25rem;
}

.classtoper-admin > .container-fluid.admin-main-wrap {
    max-width: 100%;
}

/* Question (and similar) cards: tap-sized action grid */
.admin-mobile-actions {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.5rem;
    margin-top: 0.25rem;
}

.admin-mobile-actions > .btn,
.admin-mobile-actions > a.btn,
.admin-mobile-actions > .admin-mobile-action-form {
    width: 100%;
    min-height: 2.75rem;
    align-self: stretch;
}

.admin-mobile-actions .admin-mobile-action-form .btn {
    width: 100%;
    min-height: 2.75rem;
}

/* Three+ primary actions: one column (e.g. quiz View / Edit / Delete) */
.admin-mobile-actions.admin-mobile-actions--stack {
    grid-template-columns: 1fr;
}

@media (max-width: 767.98px) {
    body.classtoper-admin {
        background-color: #e8ecf3;
        -webkit-text-size-adjust: 100%;
    }

    .classtoper-admin > .container-fluid.admin-main-wrap {
        margin-top: 0.75rem !important;
        padding-left: max(0.75rem, env(safe-area-inset-left, 0px));
        padding-right: max(0.75rem, env(safe-area-inset-right, 0px));
        padding-bottom: calc(1.25rem + env(safe-area-inset-bottom, 0px));
    }

    .classtoper-admin .admin-page-header {
        margin-bottom: 1rem;
        padding-bottom: 0.65rem;
    }

    .classtoper-admin .admin-page-header .d-flex.gap-2 {
        flex-direction: column;
        width: 100%;
        align-self: stretch !important;
    }

    .classtoper-admin .admin-page-header .d-flex.gap-2 .btn {
        width: 100%;
        min-height: 2.75rem;
    }

    .classtoper-admin .admin-page-header > .btn {
        width: 100%;
        align-self: stretch !important;
        min-height: 2.75rem;
    }

    /* Create / edit forms: full-width stacked primary + cancel (all admin-form-card pages) */
    .classtoper-admin .admin-form-card form .d-flex:has(> button[type="submit"]),
    .classtoper-admin .admin-form-card form .d-flex:has(> input[type="submit"]),
    .classtoper-admin .admin-form-card form .d-flex:has(> a.btn-primary) {
        flex-direction: column !important;
        align-items: stretch !important;
        gap: 0.5rem !important;
    }

    .classtoper-admin .admin-form-card form .d-flex.justify-content-between:has(button[type="submit"]),
    .classtoper-admin .admin-form-card form .d-flex.justify-content-between:has(input[type="submit"]) {
        flex-direction: column-reverse !important;
    }

    .classtoper-admin .admin-form-card form .d-flex:has(> button[type="submit"]) > .btn,
    .classtoper-admin .admin-form-card form .d-flex:has(> button[type="submit"]) > a.btn,
    .classtoper-admin .admin-form-card form .d-flex:has(> input[type="submit"]) > .btn,
    .classtoper-admin .admin-form-card form .d-flex:has(> a.btn-primary) > .btn,
    .classtoper-admin .admin-form-card form .d-flex:has(> a.btn-primary) > a.btn,
    .classtoper-admin .admin-form-card form .d-flex.justify-content-between:has(button[type="submit"]) .btn,
    .classtoper-admin .admin-form-card form .d-flex.justify-content-between:has(button[type="submit"]) a.btn {
        width: 100% !important;
        min-height: 2.75rem;
    }

    /* Help column hidden on md+ only — show below form on phones */
    .classtoper-admin .row > .col-md-4.d-none.d-md-block {
        display: block !important;
        width: 100% !important;
        max-width: 100% !important;
        flex: 0 0 100% !important;
        margin-top: 0.75rem !important;
    }

    .classtoper-admin .row > .col-md-4.d-none.d-md-block .card {
        border-radius: 0.75rem;
    }

    /* Stack every filter column (beats col-6 / col-sm-auto between 576–767px) */
    .classtoper-admin .admin-filter-card form .row > [class*="col-"] {
        flex: 0 0 100% !important;
        max-width: 100% !important;
        width: 100% !important;
    }

    .classtoper-admin .admin-filter-card .form-select,
    .classtoper-admin .admin-filter-card .form-control {
        min-height: 2.75rem;
        font-size: 1rem;
        padding-top: 0.5rem;
        padding-bottom: 0.5rem;
    }

    .classtoper-admin .admin-filter-card .btn {
        min-height: 2.75rem;
        font-size: 0.9375rem;
    }

    /* Filter row: full-width Apply / Clear (column is already 100% on small screens) */
    .classtoper-admin .admin-filter-card form .row > [class*="col-"] .btn,
    .classtoper-admin .admin-filter-card form .row > [class*="col-"] a.btn {
        width: 100%;
    }

    .classtoper-admin .admin-filter-card form .row > [class*="col-"].d-flex.gap-1,
    .classtoper-admin .admin-filter-card form .row > [class*="col-"].d-flex.gap-2 {
        display: grid !important;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 0.5rem !important;
    }

    .classtoper-admin .admin-filter-card .card-body {
        padding: 0.875rem 1rem;
    }

    .classtoper-admin .admin-list-card .card-body,
    .classtoper-admin .admin-form-card .card-body {
        padding: 0.875rem 1rem;
    }

    .classtoper-admin .admin-list-card,
    .classtoper-admin .admin-filter-card,
    .classtoper-admin .admin-form-card {
        border-radius: 0.75rem;
        box-shadow: 0 2px 8px rgba(15, 23, 42, 0.06);
    }

    .classtoper-admin .admin-mobile-card {
        border-radius: 0.75rem;
        border: 1px solid rgba(0, 0, 0, 0.06);
        box-shadow: 0 2px 10px rgba(15, 23, 42, 0.06);
    }

    .classtoper-admin .admin-mobile-card .card-body.d-flex.justify-content-between {
        flex-direction: column;
        align-items: stretch !important;
        gap: 0.75rem;
    }

    .classtoper-admin .admin-mobile-card .d-flex.gap-1.flex-shrink-0 {
        width: 100%;
        display: grid !important;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 0.5rem;
    }

    .classtoper-admin .admin-mobile-card .d-flex.gap-1.flex-shrink-0 .btn {
        width: 100%;
        min-height: 2.75rem;
    }

    .classtoper-admin .admin-mobile-card .d-flex.flex-wrap.gap-1 {
        width: 100%;
        display: grid !important;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 0.5rem !important;
    }

    .classtoper-admin .admin-mobile-card .d-flex.flex-wrap.gap-1 > .btn,
    .classtoper-admin .admin-mobile-card .d-flex.flex-wrap.gap-1 > a.btn,
    .classtoper-admin .admin-mobile-card .d-flex.flex-wrap.gap-1 > form {
        width: 100%;
        min-height: 2.75rem;
    }

    .classtoper-admin .admin-mobile-card .d-flex.flex-wrap.gap-1 form .btn {
        width: 100%;
        min-height: 2.75rem;
    }

    .classtoper-admin .admin-form-card .form-control:not(textarea),
    .classtoper-admin .admin-form-card .form-select {
        min-height: 2.75rem;
        font-size: 1rem;
    }

    .classtoper-admin .alert.d-flex.flex-wrap {
        flex-direction: column;
        align-items: stretch !important;
    }

    .classtoper-admin .alert.d-flex .btn {
        width: 100%;
    }
}

@media (max-width: 575.98px) {
    .classtoper-admin .admin-modal .modal-footer {
        flex-direction: column-reverse;
        align-items: stretch;
        gap: 0.5rem;
    }

    .classtoper-admin .admin-modal .modal-footer .btn {
        width: 100%;
        margin: 0;
    }

    .classtoper-admin .admin-modal .modal-dialog.modal-fullscreen-sm-down .modal-body {
        -webkit-overflow-scrolling: touch;
    }
}

/* Quiz create/edit — Select2 chapter multiselect (single line, centered tags) */
.classtoper-admin .quiz-chapter-select2 + .select2-container {
    min-height: 38px;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple {
    display: flex;
    align-items: center;
    box-sizing: border-box;
    height: 38px;
    min-height: 38px;
    max-height: 38px;
    padding: 0 0.4rem;
    overflow: hidden;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-selection__rendered {
    display: flex !important;
    flex: 1 1 auto;
    flex-wrap: nowrap;
    align-items: center !important;
    align-content: center;
    float: none !important;
    width: 100%;
    height: 100%;
    max-height: none;
    padding: 0 !important;
    margin: 0 !important;
    overflow: hidden;
    white-space: nowrap;
    box-sizing: border-box;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-selection__choice {
    float: none !important;
    display: inline-flex !important;
    align-items: center;
    flex: 0 0 auto;
    max-width: 9.5rem;
    overflow: hidden;
    margin: 0 0.25rem 0 0 !important;
    padding-top: 0.1rem;
    padding-bottom: 0.1rem;
    font-size: 0.8125rem;
    line-height: 1.2;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-selection__choice__display {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    max-width: 100%;
    line-height: 1.2;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-selection__choice--overflow {
    float: none !important;
    display: inline-flex !important;
    align-items: center;
    flex: 0 0 auto;
    max-width: none;
    margin: 0 0.25rem 0 0 !important;
    background: var(--bs-secondary-bg, #e9ecef);
    border: 1px solid var(--bs-border-color, #dee2e6);
    color: var(--bs-secondary-color, #6c757d);
    padding: 0.1rem 0.45rem;
    font-size: 0.75rem;
    font-weight: 600;
    cursor: default;
    list-style: none;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-search--inline {
    float: none !important;
    display: inline-flex !important;
    align-items: center;
    flex: 1 1 2rem;
    min-width: 1.5rem;
    max-width: 100%;
    margin: 0 !important;
    padding: 0;
}

.classtoper-admin .quiz-chapter-select2 + .select2-container .select2-selection--multiple .select2-search--inline .select2-search__field {
    margin: 0 !important;
    padding: 0;
    height: 1.5rem;
    line-height: 1.5rem;
    vertical-align: middle;
}

/* Tickets nav — open ticket count badge */
.classtoper-admin .navbar-nav .nav-link.st-ticket-nav-item {
    padding-right: 2.25rem !important;
}

.classtoper-admin .st-ticket-nav-badge {
    position: absolute;
    top: 0.35rem;
    right: 0.15rem;
    font-size: 0.625rem;
    line-height: 1.15;
    min-width: 1.1rem;
    padding: 0.2em 0.4em;
    font-weight: 700;
    border: 1px solid rgba(255, 255, 255, 0.85);
}

.classtoper-admin .st-ticket-thread {
    max-height: 22rem;
    overflow-y: auto;
}

.classtoper-admin .st-ticket-bubble {
    border-radius: 0.5rem;
    padding: 0.5rem 0.65rem;
}

.classtoper-admin .st-ticket-bubble--student {
    background: #e7f1ff;
    border: 1px solid #cfe2ff;
    margin-right: 2rem;
}

.classtoper-admin .st-ticket-bubble--admin {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    margin-left: 2rem;
}

.classtoper-admin .st-ticket-bubble--system {
    background: #fff8e6;
    border: 1px dashed #ffc107;
    font-style: italic;
}

/* --- Student assignment drag-and-drop ----------------------------------- */
.classtoper-admin .st-assign-layout {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 0.75rem;
    align-items: stretch;
}

@media (max-width: 991.98px) {
    .classtoper-admin .st-assign-layout {
        grid-template-columns: 1fr;
    }
    .classtoper-admin .st-assign-mid-tools {
        flex-direction: row !important;
        justify-content: center;
    }
}

.classtoper-admin .st-assign-dropzone {
    border: 2px dashed var(--admin-card-border);
    border-radius: 0.5rem;
    min-height: 280px;
    display: flex;
    flex-direction: column;
    background: #fff;
    transition: border-color 0.2s, box-shadow 0.2s;
    cursor: pointer;
}

.classtoper-admin .st-assign-dropzone--active,
.classtoper-admin .st-assign-dropzone:focus-within {
    border-color: #0d6efd;
    box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.15);
}

.classtoper-admin .st-assign-dropzone--over {
    border-color: #198754;
    background: #f0fff4;
}

.classtoper-admin .st-assign-dropzone__head {
    padding: 0.65rem 0.85rem;
    border-bottom: 1px solid var(--admin-card-border);
    background: var(--admin-header-bg);
    border-radius: 0.45rem 0.45rem 0 0;
    font-weight: 600;
    font-size: 0.9rem;
}

.classtoper-admin .st-assign-dropzone__body {
    flex: 1;
    padding: 0.65rem;
    overflow-y: auto;
    max-height: 360px;
}

.classtoper-admin .st-assign-filter-panel {
    display: none;
    padding: 0.75rem;
    border-bottom: 1px solid var(--admin-card-border);
    background: #fafbfc;
}

.classtoper-admin .st-assign-filter-panel--open {
    display: block;
}

.classtoper-admin .st-assign-chip {
    display: flex;
    align-items: flex-start;
    gap: 0.35rem;
    padding: 0.45rem 0.5rem;
    margin-bottom: 0.4rem;
    border: 1px solid var(--admin-card-border);
    border-radius: 0.375rem;
    background: #fff;
    cursor: grab;
    user-select: none;
}

.classtoper-admin .st-assign-chip--dragging {
    opacity: 0.55;
    cursor: grabbing;
}

.classtoper-admin .st-assign-chip__grip {
    color: #adb5bd;
    line-height: 1;
}

.classtoper-admin .st-assign-chip__body {
    flex: 1;
    min-width: 0;
}

.classtoper-admin .st-assign-chip__name {
    display: block;
    font-size: 0.875rem;
}

.classtoper-admin .st-assign-chip__meta {
    display: block;
    font-size: 0.75rem;
    color: #6c757d;
}

.classtoper-admin .st-assign-chip__remove {
    padding: 0 0.25rem;
    line-height: 1;
    text-decoration: none;
    color: #dc3545;
}

.classtoper-admin .st-assign-empty,
.classtoper-admin .st-assign-loading {
    margin: 0.5rem 0;
    text-align: center;
    font-size: 0.85rem;
}

.classtoper-admin .st-assign-mid-tools {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 0.35rem;
    padding-top: 2.5rem;
}