.modal-backdrop {
            position: fixed;
            inset: 0;
            background: color-mix(in srgb, var(--color-text) 45%, transparent);
            backdrop-filter: blur(3px);
            display: none;
            align-items: center;
            justify-content: center;
            z-index: 10000;
            padding: 18px;
        }

        .modal-backdrop.show {
            display: flex;
        }

        .confirm-modal {
            width: min(480px, 100%);
            background: var(--color-surface);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-lg);
            box-shadow: 0 20px 40px color-mix(in srgb, var(--color-text) 40%, transparent);
            padding: 24px;
            animation: modalIn 0.2s ease-out;
        }

        @keyframes modalIn {
            from {
                opacity: 0;
                transform: scale(0.95) translateY(-10px);
            }

            to {
                opacity: 1;
                transform: scale(1) translateY(0);
            }
        }

        .confirm-modal h3 {
            color: var(--color-text);
            font-size: 1.2rem;
            margin-bottom: 8px;
        }

        .confirm-modal p {
            color: var(--color-text-muted);
            line-height: 1.6;
            margin-bottom: 0;
        }

        .confirm-actions {
            display: flex;
            justify-content: flex-end;
            gap: 10px;
            margin-top: 20px;
        }

        .confirm-btn {
            border: none;
            border-radius: var(--radius-md);
            padding: 10px 18px;
            font-weight: 700;
            font-size: 0.9rem;
            cursor: pointer;
            transition: opacity 0.15s;
        }

        .confirm-btn:hover {
            opacity: 0.85;
        }

        .confirm-cancel {
            background: var(--color-background-alt);
            color: var(--color-text);
        }

        .confirm-danger {
            background: var(--color-danger);
            color: var(--color-text-on-primary);
        }

        .confirm-success {
            background: var(--color-primary);
            color: var(--color-text-on-primary);
        }

        .tab-warn {
            color: var(--color-danger);
            font-weight: 800;
            animation: tab-pulse 1s ease-in-out 3;
        }

        .upload-dropzone-large {
            min-height: 210px;
            border: 3px dashed var(--color-border);
            border-radius: var(--radius-2xl);
            background: var(--color-surface-interactive);
            color: var(--color-text-muted);
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            padding: 3rem 2rem;
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .upload-dropzone-large:hover,
        .upload-dropzone-large:focus-within,
        .upload-dropzone-large.is-dragover {
            border-color: var(--color-primary);
            background: var(--color-primary-light);
            transform: scale(1.01);
        }

        .upload-dropzone-content {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 10px;
            width: 100%;
            max-width: 520px;
        }

        .upload-dropzone-icon {
            font-size: 1.9rem;
            line-height: 1;
        }

        .upload-dropzone-title {
            font-weight: 700;
            color: var(--color-text);
        }

        .upload-dropzone-hint {
            font-size: 0.88rem;
            color: var(--color-text-muted);
            margin: 0;
        }

        .presentation-info {
            margin-top: 8px;
            padding: 0;
            border-radius: var(--radius-md);
            border: 1px solid rgba(var(--color-primary-rgb), 0.2);
            background: var(--color-surface);
            color: var(--color-text);
            font-size: 0.88rem;
            overflow: hidden;
        }

        /* ── Upload Skeleton ── */
        .upload-skeleton {
            padding: 16px;
        }

        .upload-skeleton-header {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 14px;
        }

        .upload-skeleton-spinner {
            width: 32px;
            height: 32px;
            border: 3px solid var(--color-border-light);
            border-top-color: var(--color-primary);
            border-radius: 50%;
            flex-shrink: 0;
            animation: upload-skeleton-spin 0.8s linear infinite;
        }

        .upload-skeleton-meta {
            flex: 1;
            min-width: 0;
        }

        .upload-skeleton-title {
            font-weight: 700;
            font-size: 0.9rem;
            color: var(--color-text);
            margin-bottom: 2px;
        }

        .upload-skeleton-file {
            font-size: 0.8rem;
            color: var(--color-text-muted);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .upload-skeleton-bars {
            display: flex;
            flex-direction: column;
            gap: 8px;
            margin-bottom: 14px;
        }

        .upload-skeleton-bar {
            height: 12px;
            border-radius: var(--radius-full);
            background: linear-gradient(90deg,
                var(--color-bg-secondary) 25%,
                rgba(var(--color-primary-rgb), 0.12) 50%,
                var(--color-bg-secondary) 75%);
            background-size: 200% 100%;
            animation: upload-skeleton-shimmer 1.4s ease-in-out infinite;
        }

        .upload-skeleton-progress {
            margin-top: 2px;
        }

        .upload-skeleton-progress-track {
            height: 6px;
            border-radius: var(--radius-full);
            background: var(--color-bg-secondary);
            overflow: hidden;
        }

        .upload-skeleton-progress-fill {
            height: 100%;
            border-radius: var(--radius-full);
            background: linear-gradient(90deg, var(--color-primary), var(--color-primary-dark, var(--color-primary)));
            animation: upload-skeleton-indeterminate 1.6s ease-in-out infinite;
        }

        @keyframes upload-skeleton-spin {
            to { transform: rotate(360deg); }
        }

        @keyframes upload-skeleton-shimmer {
            0%   { background-position: 100% 0; }
            100% { background-position: -100% 0; }
        }

        @keyframes upload-skeleton-indeterminate {
            0%   { width: 0%; margin-left: 0; }
            50%  { width: 60%; margin-left: 20%; }
            100% { width: 0%; margin-left: 100%; }
        }

        .presentation-control-hint {
            margin: 12px 0 0;
            padding: 10px 14px;
            border-radius: var(--radius-sm);
            border: 1px solid var(--color-border-light);
            background: var(--color-bg-secondary);
            color: var(--color-text-muted);
            font-size: 0.85rem;
            line-height: 1.5;
        }

        .presentation-control-hint strong {
            color: var(--color-text);
        }

        @keyframes tab-pulse {

            0%,
            100% {
                opacity: 1;
            }

            50% {
                opacity: 0.4;
            }
        }

        /* ── Split Layout: Slide List + Preview ── */
        .slide-list.slide-list-split {
            display: grid;
            grid-template-columns: 260px 1fr;
            gap: 14px;
            min-height: 640px;
            align-items: start;
            border: none;
            background: none;
            padding: 0;
        }

        .split-sidebar {
            border: 2px solid var(--color-border);
            border-radius: var(--radius-lg);
            background: var(--color-surface-interactive);
            overflow-y: hidden;
            height: auto;
            max-height: 450px;
            align-self: start;
            padding: 0;
            display: flex;
            flex-direction: column;
        }

        .sidebar-items {
            overflow-y: auto;
            flex: 1;
            padding: 0.5rem;
            min-height: 0;
        }

        .sidebar-footer {
            border-top: 1px solid var(--color-border);
            padding: 0.5rem;
            flex-shrink: 0;
        }

        .sidebar-clear-btn {
            width: 100%;
            padding: 0.45rem 0.75rem;
            background: transparent;
            border: 1.5px solid var(--color-danger, #e53e3e);
            color: var(--color-danger, #e53e3e);
            border-radius: var(--radius-md);
            font-size: 0.8rem;
            font-weight: 600;
            cursor: pointer;
            transition: background 0.15s, color 0.15s;
            letter-spacing: 0.01em;
        }

        .sidebar-clear-btn:hover {
            background: var(--color-danger, #e53e3e);
            color: #fff;
        }

        .mini-item {
            display: flex;
            align-items: center;
            gap: 0.75rem;
            padding: 0.75rem 1rem;
            background: var(--color-surface);
            border-radius: var(--radius-md);
            border: 2px solid transparent;
            margin-bottom: 0.5rem;
            cursor: pointer;
            transition: all 0.2s;
            font-size: 0.9rem;
            box-shadow: var(--shadow-sm);
        }

        .mini-item:last-child {
            margin-bottom: 0;
        }

        .mini-item:hover {
            background: var(--color-primary-light);
            transform: translateX(2px);
        }

        .mini-item.active {
            border-color: var(--color-primary);
            background: var(--color-primary-light);
            box-shadow: inset 4px 0 0 var(--color-primary), 0 4px 6px -1px rgba(var(--color-primary-rgb), 0.15);
        }

        .mini-item.loading {
            cursor: default;
            border-color: rgba(var(--color-info-rgb), 0.25);
        }

        .mini-name-skeleton {
            display: inline-block;
            max-width: 100%;
            background: linear-gradient(90deg,
                    rgba(var(--color-info-rgb), 0.08) 25%,
                    rgba(var(--color-info-rgb), 0.2) 50%,
                    rgba(var(--color-info-rgb), 0.08) 75%);
            background-size: 200% 100%;
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            animation: linked-loader-shimmer 1.2s ease-in-out infinite;
        }

        .mini-num {
            font-weight: 800;
            color: var(--color-primary);
            background: var(--color-surface-elevated);
            width: 24px;
            height: 24px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            font-size: 0.75rem;
            box-shadow: var(--shadow-sm);
            min-width: 24px;
        }

        .mini-name {
            flex: 1;
            min-width: 0;
            display: flex;
            align-items: baseline;
            color: var(--color-text);
        }

        .mini-name-base {
            min-width: 0;
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
            flex: 1 1 auto;
        }

        .mini-name-ext {
            flex-shrink: 0;
            white-space: nowrap;
        }

        /* Preview Pane */
        .split-preview {
            border: 2px solid var(--color-border);
            border-radius: var(--radius-lg);
            background: var(--color-surface);
            padding: 1.5rem;
            display: flex;
            flex-direction: column;
            overflow-y: auto;
            max-height: 650px;
            box-shadow: var(--shadow-sm);
        }

        .split-preview-empty {
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--color-text-muted);
            font-size: 0.9rem;
            flex: 1;
        }

        .preview-header {
            display: flex;
            align-items: center;
            gap: 10px;
            margin-bottom: 16px;
            padding-bottom: 12px;
            border-bottom: 1px solid var(--color-border);
        }

        .preview-info {
            flex: 1;
        }

        .preview-title {
            font-weight: 700;
            font-size: 1rem;
        }

        .preview-chip {
            display: inline-block;
            margin-left: 8px;
            padding: 2px 8px;
            border-radius: var(--radius-full);
            font-size: 0.68rem;
            font-weight: 700;
            letter-spacing: 0.02em;
            color: var(--color-primary);
            background: var(--color-primary-light);
            border: 1px solid rgba(var(--color-info-rgb), 0.35);
            vertical-align: middle;
        }

        .preview-format-chip {
            margin-left: 0;
            min-width: 40px;
            text-align: center;
            text-transform: lowercase;
        }

        .preview-subtitle {
            font-size: 0.8rem;
            color: var(--color-text-muted);
        }

        .preview-actions {
            display: flex;
            gap: 6px;
        }

        .preview-btn {
            padding: 6px 12px;
            border: 1px solid var(--color-border);
            border-radius: var(--radius-sm);
            background: var(--color-surface);
            color: var(--color-text-muted);
            font-size: 0.78rem;
            cursor: pointer;
            transition: all 150ms ease;
            font-family: inherit;
        }

        .preview-btn:hover {
            background: var(--color-primary);
            color: var(--color-text-on-primary);
            border-color: var(--color-primary);
        }

        .preview-btn.danger {
            background: var(--color-danger-soft-bg);
            border-color: var(--color-danger-soft-border);
            color: var(--color-danger-strong);
        }

        .preview-btn.danger:hover {
            background: var(--color-danger);
            border-color: var(--color-danger);
            color: var(--color-text-on-primary);
        }

        .preview-btn:disabled {
            opacity: 0.3;
            cursor: not-allowed;
        }

        .preview-btn:disabled:hover {
            background: var(--color-surface);
            color: var(--color-text-muted);
            border-color: var(--color-border);
        }

        .preview-body {
            flex: 1;
        }

        .preview-section-title {
            font-size: 0.78rem;
            font-weight: 700;
            color: var(--color-text-muted);
            text-transform: uppercase;
            letter-spacing: 0.5px;
            margin-bottom: 8px;
            margin-top: 12px;
        }

        .preview-section-title:first-child {
            margin-top: 0;
        }

        .linked-assets {
            display: flex;
            flex-wrap: nowrap;
            gap: 10px;
            overflow-x: auto;
            overflow-y: hidden;
            padding: 2px 2px 10px;
            margin-bottom: 8px;
            scrollbar-width: thin;
            scrollbar-color: var(--color-primary) var(--color-bg-secondary);
        }

        .linked-assets-nav {
            display: flex;
            align-items: center;
            gap: 8px;
            margin-bottom: 8px;
        }

        .linked-assets-arrow {
            width: 28px;
            height: 28px;
            flex: 0 0 28px;
            border-radius: var(--radius-full);
            border: 1px solid var(--color-border);
            background: var(--color-surface);
            color: var(--color-text-secondary);
            font-size: 0.8rem;
            line-height: 1;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
        }

        .linked-assets-arrow:hover {
            background: var(--color-primary-soft);
            color: var(--color-primary);
            border-color: rgba(var(--color-info-rgb), 0.4);
        }

        .linked-assets-nav .linked-assets {
            flex: 1;
            margin-bottom: 0;
        }

        .linked-assets.linked-assets--centered {
            justify-content: center;
        }

        .linked-assets::-webkit-scrollbar {
            height: 10px;
        }

        .linked-assets::-webkit-scrollbar-track {
            background: var(--color-bg-secondary);
            border-radius: var(--radius-full);
        }

        .linked-assets::-webkit-scrollbar-thumb {
            background: var(--color-primary);
            border-radius: var(--radius-full);
            border: 2px solid var(--color-bg-secondary);
        }

        .asset-card {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 8px 12px;
            background: var(--color-surface);
            border: 1px solid rgba(var(--color-info-rgb), 0.25);
            border-radius: var(--radius-sm);
            font-size: 0.8rem;
            min-width: 220px;
            max-width: 220px;
            flex-shrink: 0;
        }

        .asset-card-main {
            min-width: 0;
            flex: 1;
        }

        .asset-thumb {
            width: 32px;
            height: 32px;
            border-radius: var(--radius-xs);
            background: var(--color-bg-secondary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1rem;
        }

        .asset-thumb-image {
            width: 32px;
            height: 32px;
            border-radius: var(--radius-xs);
            object-fit: contain;
            object-position: center;
            border: 1px solid var(--color-border-light);
            background: #fff;
            display: block;
               cursor: zoom-in;
        }

    .asset-hover-preview {
        position: fixed;
        z-index: 11000;
        width: min(320px, 36vw);
        max-height: 42vh;
        padding: 6px;
        border-radius: 10px;
        border: 1px solid rgba(148, 163, 184, 0.45);
        background: #fff;
        backdrop-filter: blur(2px);
        box-shadow: 0 14px 38px rgba(2, 6, 23, 0.6);
        pointer-events: none;
        opacity: 0;
        transform: scale(0.96);
        transition: opacity 120ms ease, transform 120ms ease;
    }

    .asset-hover-preview.visible {
        opacity: 1;
        transform: scale(1);
    }

    .asset-hover-preview-image {
        display: block;
        width: 100%;
        height: auto;
        max-height: calc(42vh - 12px);
        border-radius: 6px;
        object-fit: contain;
        background: #fff;
    }

        .asset-name {
            color: var(--color-text);
        }

        .asset-origin {
            font-size: 0.7rem;
            color: var(--color-text-muted);
            margin-top: 2px;
            text-transform: none;
        }

        .linked-assets-strip {
            margin-bottom: 8px;
        }

        .linked-assets-title-bar {
            display: block;
            width: 100%;
            margin-bottom: 8px;
            padding: 8px 10px;
            border: 1px solid var(--color-border);
            border-radius: var(--radius-sm);
            background: var(--color-background-alt);
        }

        .asset-status {
            font-size: 0.7rem;
            color: var(--color-primary);
            font-weight: 600;
        }

        .asset-remove-btn {
            width: 22px;
            height: 22px;
            flex: 0 0 22px;
            border-radius: var(--radius-full);
            border: 1px solid var(--color-border);
            background: var(--color-surface);
            color: var(--color-text-muted);
            font-size: 0.72rem;
            line-height: 1;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
        }

        .asset-remove-btn:hover {
            background: color-mix(in srgb, var(--color-danger) 15%, var(--color-surface));
            color: var(--color-danger);
            border-color: color-mix(in srgb, var(--color-danger) 40%, var(--color-border));
        }

        .preview-code {
            background: var(--color-code-bg);
            color: var(--color-code-text);
            border: none;
            border-radius: var(--radius-lg);
            padding: 1.5rem;
            font-family: 'JetBrains Mono', 'Fira Code', monospace;
            font-size: 0.9rem;
            line-height: 1.5;
            overflow: auto;
            max-height: 450px;
            white-space: pre-wrap;
            word-break: break-word;
            box-shadow: inset 0 2px 4px color-mix(in srgb, var(--color-text) 20%, transparent);
        }

        .preview-loading {
            background: var(--color-surface);
            border: 1px dashed var(--color-border);
            border-radius: var(--radius-sm);
            padding: 12px;
            color: var(--color-text-muted);
            font-size: 0.82rem;
        }

        .preview-loading-state {
            display: flex;
            align-items: center;
            gap: 12px;
            background: var(--color-surface);
            border: 1px dashed var(--color-border);
            border-radius: var(--radius-sm);
            padding: 14px;
        }

        .loader-circle {
            width: 20px;
            height: 20px;
            border: 2px solid var(--color-border-light);
            border-top-color: var(--color-primary);
            border-radius: 50%;
            flex: 0 0 20px;
            animation: linked-loader-spin 0.9s linear infinite;
        }

        .preview-loading-title {
            font-size: 0.86rem;
            font-weight: 700;
            color: var(--color-text);
            margin-bottom: 2px;
        }

        .preview-loading-text {
            font-size: 0.78rem;
            color: var(--color-text-muted);
        }

        @keyframes linked-loader-spin {
            to {
                transform: rotate(360deg);
            }
        }

        @keyframes linked-loader-shimmer {
            0% {
                background-position: 100% 0;
            }

            100% {
                background-position: -100% 0;
            }
        }

        .preview-image-grid {
            display: grid;
            grid-template-columns: minmax(0, 1fr);
            gap: 10px;
            margin-bottom: 8px;
        }

        .preview-image-card {
            margin: 0;
            background: #fff;
            border: 1px solid var(--color-border-light);
            border-radius: var(--radius-sm);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
        }

        .preview-image {
            width: 100%;
            max-height: 360px;
            display: block;
            object-fit: contain;
            background: #fff;
        }

        /* Drag-and-drop on sidebar items */
        .mini-item[draggable="true"] {
            cursor: grab;
        }

        .mini-item.dragging {
            opacity: 0.4;
            cursor: grabbing;
        }

        .mini-item.drag-over {
            border: 1.5px dashed var(--color-primary);
            background: var(--color-primary-light);
        }

        @media (max-width: 700px) {
            .slide-list.slide-list-split {
                grid-template-columns: 1fr;
            }

            .split-sidebar {
                max-height: 200px;
            }
        }

        /* Accessibility pass for Professor panel */
        .page-professor .upload-dropzone-large:focus-visible,
        .page-professor .preview-btn:focus-visible,
        .page-professor .mini-item:focus-visible,
        .page-professor .sidebar-clear-btn:focus-visible,
        .page-professor .asset-remove-btn:focus-visible,
        .page-professor #openPresentationBtn:focus-visible,
        .page-professor .confirm-btn:focus-visible,
        .page-professor .header-home-link:focus-visible,
        .page-professor .lang-toggle:focus-visible,
        .page-professor .theme-toggle:focus-visible {
            outline: 3px solid var(--color-primary);
            outline-offset: 2px;
        }

        .page-professor .presentation-error {
            border-left: 4px solid var(--color-danger);
        }

        .page-professor .presentation-error-title {
            color: var(--color-danger-strong, var(--color-danger));
        }

        .page-professor .presentation-control-hint {
            border-color: color-mix(in srgb, var(--color-primary) 30%, var(--color-border));
            background: color-mix(in srgb, var(--color-primary) 8%, var(--color-surface));
        }

        @media (prefers-reduced-motion: reduce) {
            .page-professor #openPresentationBtn:not(:disabled) {
                animation: none !important;
            }

            .page-professor .settings-group:hover,
            .page-professor .upload-dropzone-large:hover,
            .page-professor .upload-dropzone-large:focus-within,
            .page-professor .upload-dropzone-large.is-dragover,
            .page-professor .mini-item:hover,
            .page-professor .preview-btn:hover {
                transform: none !important;
            }
        }

/* Professor reimagined production shell */
.page-professor.professor-reimagined {
    --prof-shell-width: 1240px;
    --prof-surface: #ffffff;
    --prof-surface-soft: #f8fafc;
    --prof-text: #0f172a;
    --prof-text-muted: #64748b;
    --prof-border: rgba(174, 193, 200, 0.34);
    --prof-border-soft: rgba(182, 200, 206, 0.2);
    --prof-focus: rgba(var(--color-primary-rgb), 0.35);
    --prof-header-pattern-opacity: 0.62;
    --prof-shadow-1: 0 4px 16px rgba(6, 34, 39, 0.05);
    --prof-shadow-2: 0 10px 28px rgba(6, 34, 39, 0.08);
    min-height: 100vh;
    margin: 0;
    color: var(--prof-text);
    background:
        radial-gradient(circle at 8% 10%, rgba(var(--color-header-hero-end-rgb), 0.08), transparent 30%),
        radial-gradient(circle at 90% 20%, rgba(var(--color-header-hero-start-rgb), 0.05), transparent 25%),
        linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
}

.page-professor.professor-reimagined #bgPatternCanvas {
    z-index: 0 !important;
}

.page-professor.professor-reimagined .hero-header {
    position: relative;
    z-index: 1;
    overflow: hidden;
    background: linear-gradient(
        165deg,
        rgba(var(--color-header-hero-start-rgb), 0.94),
        rgba(var(--color-header-hero-end-rgb), 0.86)
    );
    color: #ffffff;
    padding: 0;
    text-align: left;
}

.page-professor.professor-reimagined .hero-header::before {
    content: "";
    position: absolute;
    inset: 0;
    z-index: 1;
    background-image:
        url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100%25' height='100%25'%3E%3Ctext x='10%25' y='20%25' fill='rgba(255,255,255,0.05)' font-size='20'%3E%E2%88%82%3C/text%3E%3Ctext x='80%25' y='15%25' fill='rgba(255,255,255,0.05)' font-size='24'%3E%E2%88%9E%3C/text%3E%3Ctext x='40%25' y='80%25' fill='rgba(255,255,255,0.08)' font-size='22'%3E%CE%B1%3C/text%3E%3Ctext x='90%25' y='75%25' fill='rgba(255,255,255,0.06)' font-size='18'%3E%C2%B1%3C/text%3E%3Ctext x='60%25' y='60%25' fill='rgba(255,255,255,0.05)' font-size='16'%3E%CE%BB%3C/text%3E%3Ctext x='12%25' y='60%25' fill='rgba(255,255,255,0.04)' font-size='18'%3E%E2%88%86%3C/text%3E%3Ctext x='25%25' y='10%25' fill='rgba(255,255,255,0.07)' font-size='14'%3E%C2%B1%3C/text%3E%3Ctext x='55%25' y='25%25' fill='rgba(255,255,255,0.06)' font-size='20'%3E%E2%88%A9%3C/text%3E%3Ctext x='95%25' y='40%25' fill='rgba(255,255,255,0.05)' font-size='20'%3E%E2%88%82%3C/text%3E%3Ctext x='85%25' y='90%25' fill='rgba(255,255,255,0.06)' font-size='18'%3E%E2%88%86%3C/text%3E%3Ctext x='70%25' y='15%25' fill='rgba(255,255,255,0.04)' font-size='16'%3E%E2%88%82%3C/text%3E%3C/svg%3E"),
        radial-gradient(circle at 25% 25%, rgba(255, 255, 255, 0.12) 1px, transparent 2px),
        linear-gradient(30deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px),
        linear-gradient(150deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
    background-size: 100% 100%, 28px 24px, 24px 42px, 24px 42px;
    background-position: center center, 0 0, 0 0, 12px 21px;
    opacity: var(--prof-header-pattern-opacity);
    pointer-events: none;
}

.page-professor.professor-reimagined .hero-header::after {
    content: "";
    position: absolute;
    inset: 0;
    z-index: 2;
    background: linear-gradient(to bottom, transparent 65%, rgba(255, 255, 255, 0.15));
    opacity: 0.45;
    pointer-events: none;
}

.page-professor.professor-reimagined .hero-header h1,
.page-professor.professor-reimagined .hero-header p {
    position: relative;
    z-index: 1;
    margin: 0;
    padding: 0;
    text-shadow: none;
}

.page-professor.professor-reimagined .hero-header-inner {
    position: relative;
    z-index: 3;
    max-width: var(--prof-shell-width);
    min-height: 15rem;
    margin: 0 auto;
    padding: 1.2rem clamp(1rem, 3vw, 2rem) 5.8rem;
    display: grid;
    grid-template-columns: auto 1fr auto;
    grid-template-areas:
        "home . controls"
        "title title title"
        "subtitle subtitle subtitle";
    row-gap: 0.58rem;
    align-items: start;
    box-sizing: border-box;
}

.page-professor.professor-reimagined .header-home-link,
.page-professor.professor-reimagined .lang-toggle,
.page-professor.professor-reimagined .theme-toggle {
    height: 38px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.26);
    color: #ffffff;
    font-weight: 600;
    font-size: 0.95rem;
    backdrop-filter: blur(8px);
    box-shadow: 0 8px 18px rgba(6, 30, 37, 0.15);
    transition: transform 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.page-professor.professor-reimagined .header-home-link {
    grid-area: home;
    padding: 0 1.15rem;
    text-decoration: none;
    gap: 0;
    position: static;
    top: auto;
    left: auto;
}

.page-professor.professor-reimagined .home-link-icon {
    display: inline-flex;
    align-items: center;
    margin-right: 6px;
}

.page-professor.professor-reimagined .header-controls {
    grid-area: controls;
    justify-self: end;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    position: static;
    top: auto;
    right: auto;
}

.page-professor.professor-reimagined .lang-toggle {
    min-width: 46px;
    padding: 0 0.85rem;
}

.page-professor.professor-reimagined .theme-toggle {
    width: 38px;
    padding: 0;
    position: static;
    top: auto;
    right: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
}

.page-professor.professor-reimagined .theme-toggle svg {
    display: block;
}

.page-professor.professor-reimagined .header-home-link:hover,
.page-professor.professor-reimagined .lang-toggle:hover,
.page-professor.professor-reimagined .theme-toggle:hover {
    background: rgba(255, 255, 255, 0.28);
    transform: translateY(-1px);
    box-shadow: 0 12px 24px rgba(7, 31, 37, 0.18);
}

.page-professor.professor-reimagined .hero-brand {
    grid-area: title;
    margin: 1.4rem 0 0;
    font-family: "Inter", "Segoe UI", sans-serif;
    font-size: clamp(2.2rem, 4vw, 2.5rem);
    font-weight: 300;
    line-height: 1.1;
    letter-spacing: -0.02em;
    animation: professor-reimagined-enter-up 650ms cubic-bezier(0.2, 0.8, 0.2, 1) both;
}

.page-professor.professor-reimagined .hero-brand b {
    font-weight: 700;
}

.page-professor.professor-reimagined .hero-brand-pipe {
    color: rgba(255, 255, 255, 0.5);
    margin: 0 0.1em;
}

.page-professor.professor-reimagined .main-content {
    max-width: var(--prof-shell-width);
    margin: -2.85rem auto 0;
    padding: 0 clamp(1rem, 3vw, 2rem) 3.25rem;
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: clamp(280px, 24vw, 320px) minmax(0, 1fr);
    gap: 1.35rem;
    align-items: start;
}

.page-professor.professor-reimagined .main-content > .global-settings,
.page-professor.professor-reimagined .main-content > #tab-presentation {
    animation: professor-reimagined-enter-up 500ms cubic-bezier(0.2, 0.8, 0.2, 1) both;
}

.page-professor.professor-reimagined .main-content > #tab-presentation {
    animation-delay: 110ms;
}

.page-professor.professor-reimagined .global-settings,
.page-professor.professor-reimagined .presentation-builder {
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    border: 1px solid var(--prof-border-soft);
    border-radius: 1.35rem;
    box-shadow: var(--prof-shadow-1);
    backdrop-filter: blur(7px);
}

.page-professor.professor-reimagined .global-settings {
    margin-bottom: 0 !important;
    padding: 1.35rem;
    position: sticky;
    top: 1rem;
}

.page-professor.professor-reimagined .global-settings h2,
.page-professor.professor-reimagined .presentation-builder h2 {
    margin: 0 0 1rem;
    color: var(--prof-text);
    font-size: 1.18rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.page-professor.professor-reimagined .settings-groups {
    grid-template-columns: 1fr;
    gap: 1rem;
    max-width: none;
}

.page-professor.professor-reimagined .settings-group {
    border-radius: 1rem;
    padding: 0.95rem;
    background: #ffffff;
    border: 1px solid var(--prof-border);
    box-shadow: none;
    transition: background 250ms ease;
}

.page-professor.professor-reimagined .settings-group:hover {
    background: #f8fafc;
    transform: none;
    box-shadow: none;
}

.page-professor.professor-reimagined .settings-group-title {
    color: #0f766e;
    font-size: 0.70rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 0.65rem;
    font-weight: 700;
}

.page-professor.professor-reimagined .settings-group-fields,
.page-professor.professor-reimagined .form-group {
    display: grid;
    gap: 0.95rem;
}

.page-professor.professor-reimagined .form-group {
    align-content: start;
}

.page-professor.professor-reimagined .form-group label,
.page-professor.professor-reimagined .slide-add-row h3,
.page-professor.professor-reimagined .slide-add-controls h3,
.page-professor.professor-reimagined .presentation-builder > div > h3 {
    color: var(--prof-text);
    font-size: 0.92rem;
    font-weight: 700;
    line-height: 1.25;
}

.page-professor.professor-reimagined .form-group small,
.page-professor.professor-reimagined .upload-dropzone-hint,
.page-professor.professor-reimagined .slide-list-empty,
.page-professor.professor-reimagined #presentationErrorBox,
.page-professor.professor-reimagined .presentation-control-hint {
    color: var(--prof-text-muted);
    font-size: 0.84rem;
    line-height: 1.45;
}

.page-professor.professor-reimagined input[type="text"],
.page-professor.professor-reimagined input[type="email"],
.page-professor.professor-reimagined input[type="number"] {
    height: 2.3rem;
    min-height: 2.3rem;
    padding: 0 0.75rem;
    border-radius: 0.4rem;
    border: 1px solid var(--prof-border);
    background: #ffffff;
    color: var(--prof-text);
    transition: all 160ms ease;
    box-sizing: border-box;
}

.page-professor.professor-reimagined input::placeholder {
    color: #94a3b8;
}

.page-professor.professor-reimagined input:focus-visible,
.page-professor.professor-reimagined button:focus-visible,
.page-professor.professor-reimagined .upload-dropzone-large:focus-visible,
.page-professor.professor-reimagined .mini-item:focus-visible,
.page-professor.professor-reimagined .preview-btn:focus-visible,
.page-professor.professor-reimagined .sidebar-clear-btn:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px var(--prof-focus);
}

.page-professor.professor-reimagined .presentation-builder {
    position: relative;
    padding: 1.45rem;
    overflow: hidden;
    display: grid;
    gap: 1.25rem;
}

.page-professor.professor-reimagined .presentation-builder > div {
    margin: 0 !important;
}

.page-professor.professor-reimagined #tab-presentation {
    width: 100%;
    min-width: 0;
}

.page-professor.professor-reimagined .upload-section {
    display: grid;
    gap: 0.9rem;
}

.page-professor.professor-reimagined .presentation-builder,
.page-professor.professor-reimagined .slides-section,
.page-professor.professor-reimagined #slideList,
.page-professor.professor-reimagined .split-preview {
    min-width: 0;
}

.page-professor.professor-reimagined .upload-section-note {
    margin: 0;
    font-size: 0.88rem;
    line-height: 1.5;
    color: rgba(40, 70, 102, 0.72);
}

.page-professor.professor-reimagined .slides-section {
    display: grid;
    gap: 1rem;
}

.page-professor.professor-reimagined .slide-add-controls,
.page-professor.professor-reimagined .slide-add-row {
    border-color: var(--prof-border);
}

.page-professor.professor-reimagined .slide-add-controls {
    margin-bottom: 0 !important;
    padding-bottom: 1.2rem !important;
}

.page-professor.professor-reimagined .upload-dropzone-large {
    min-height: 12rem;
    width: 100%;
    border: 2px dashed #94a3b8;
    border-radius: 0.8rem;
    background: #ffffff;
    color: var(--prof-text-muted);
    padding: 2.25rem 1.35rem;
    transition: all 250ms ease;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.page-professor.professor-reimagined .upload-dropzone-large:hover,
.page-professor.professor-reimagined .upload-dropzone-large:focus-within,
.page-professor.professor-reimagined .upload-dropzone-large.is-dragover {
    transform: translateY(-2px);
    border-color: var(--color-primary);
    background: #f0fdfa;
    box-shadow: 0 4px 16px rgba(20, 184, 166, 0.08);
}

.page-professor.professor-reimagined .upload-dropzone-content {
    gap: 0.62rem;
    text-align: center;
    max-width: none;
}

.page-professor.professor-reimagined .upload-dropzone-icon {
    font-size: 2.2rem;
    color: #14b8a6;
    margin-bottom: 0.5rem;
}

.page-professor.professor-reimagined .upload-dropzone-title {
    font-weight: 600;
    color: var(--prof-text);
    margin-bottom: 0.6rem;
    font-size: 0.95rem;
}

.page-professor.professor-reimagined #presUnifiedUploadBtn,
.page-professor.professor-reimagined #addMessageBtn,
.page-professor.professor-reimagined #openPresentationBtn {
    border-radius: 999px;
    font-weight: 700;
    transition: transform 250ms cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 250ms ease, filter 250ms ease, background 250ms ease;
}

.page-professor.professor-reimagined #presUnifiedUploadBtn {
    border: none;
    background: #14b8a6;
    border-color: #14b8a6;
    color: #ffffff;
    padding-inline: 1.25rem;
    height: 2.35rem;
    font-size: 0.9rem;
}

.page-professor.professor-reimagined #presUnifiedUploadBtn:hover {
    transform: translateY(-2px);
    background: #0f766e;
    border-color: #0f766e;
    box-shadow: var(--prof-shadow-1);
}

.page-professor.professor-reimagined #addMessageBtn {
    background: #e0f2fe;
    color: #0369a1;
    border: none;
    height: auto;
    min-height: 2.6rem;
    font-size: 0.9rem;
    padding: 0 1.25rem;
}

.page-professor.professor-reimagined #addMessageBtn:hover {
    transform: translateY(-2px);
    background: #bae6fd;
    box-shadow: 0 4px 12px rgba(14, 165, 233, 0.15);
}

.page-professor.professor-reimagined #openPresentationBtn {
    border: none;
    background: #14b8a6;
    color: #ffffff;
    height: 3.15rem;
    opacity: 1;
    font-size: 1rem;
    box-shadow: none;
    transition: all 250ms ease;
}

.page-professor.professor-reimagined #openPresentationBtn:hover:not(:disabled) {
    transform: translateY(-2px);
    background: #0f766e;
    box-shadow: var(--prof-shadow-1);
}

.page-professor.professor-reimagined #openPresentationBtn:disabled {
    cursor: default;
    background: #cbd5e1;
    color: #f1f5f9;
}

.page-professor.professor-reimagined .slide-add-row {
    margin-bottom: 0 !important;
    padding: 1.2rem;
    border-radius: 0.8rem;
    background: #f8fafc;
    border: 1px solid var(--prof-border);
    box-shadow: none;
}

.page-professor.professor-reimagined .slide-add-row h3 {
    margin: 0 0 0.5rem;
    font-size: 0.95rem;
    font-weight: 700;
}

.page-professor.professor-reimagined .slide-add-row .input-group {
    display: grid;
    grid-template-columns: minmax(110px, 140px) minmax(0, 1fr) auto;
    align-items: stretch;
    width: 100%;
    min-width: 0;
}

.page-professor.professor-reimagined .slide-add-row .input-group input[type="text"] {
    margin: 0;
    min-width: 0;
    box-sizing: border-box;
}

.page-professor.professor-reimagined .slide-add-row .input-group input[type="text"]:first-child {
    width: 100%;
    border-top-right-radius: 0 !important;
    border-bottom-right-radius: 0 !important;
    border-right: 1px solid var(--prof-border);
}

.page-professor.professor-reimagined .slide-add-row .input-group input[type="text"]:nth-child(2) {
    width: 100%;
    border-radius: 0 !important;
    border-left: 0 !important;
    border-right: 0 !important;
}

.page-professor.professor-reimagined .slide-add-row .input-group button#addMessageBtn {
    min-width: 132px;
    border-top-left-radius: 0 !important;
    border-bottom-left-radius: 0 !important;
    margin: 0;
    white-space: nowrap;
    transform: none;
    box-shadow: none;
}

.page-professor.professor-reimagined .slide-add-row .input-group button#addMessageBtn:hover {
    transform: none;
}

.page-professor.professor-reimagined .slide-list {
    min-height: 4.6rem;
    border: 1.5px dashed #cbd5e1;
    border-radius: 0.8rem;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: border-color 200ms ease;
}

.page-professor.professor-reimagined .slide-list.slide-list-split {
    display: grid;
    grid-template-columns: minmax(200px, 240px) minmax(0, 1fr);
    gap: 16px;
    min-height: 580px;
    align-items: start;
    justify-content: stretch;
    border: none;
    background: none;
    padding: 0;
}

.page-professor.professor-reimagined .split-sidebar {
    border: 2px solid var(--prof-border);
    border-radius: 0.8rem;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    max-height: 450px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.04);
}

.page-professor.professor-reimagined .sidebar-items {
    padding: 0.5rem;
}

.page-professor.professor-reimagined .mini-item {
    border: 2px solid transparent;
    border-radius: 0.6rem;
    box-shadow: none;
    margin-bottom: 0.5rem;
}

.page-professor.professor-reimagined .mini-item:hover {
    transform: translateX(2px);
    background: rgba(20, 184, 166, 0.08);
}

.page-professor.professor-reimagined .mini-item.active {
    border-color: #14b8a6;
    background: rgba(20, 184, 166, 0.08);
    box-shadow: inset 4px 0 0 #14b8a6, 0 4px 6px -1px rgba(var(--color-primary-rgb), 0.15);
}

.page-professor.professor-reimagined .mini-num {
    background: #ffffff;
    color: #0f766e;
    box-shadow: 0 2px 8px rgba(15, 23, 42, 0.06);
}

.page-professor.professor-reimagined .split-preview {
    border: 2px solid var(--prof-border);
    border-radius: 0.8rem;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    padding: 1.25rem;
    max-height: 680px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.04);
    width: 100%;
}

.page-professor.professor-reimagined .linked-assets-nav {
    gap: 6px;
}

.page-professor.professor-reimagined .linked-assets-arrow {
    width: 24px;
    height: 24px;
    flex: 0 0 24px;
    font-size: 0.72rem;
    opacity: 0.72;
}

.page-professor.professor-reimagined .asset-card {
    min-width: 200px;
    max-width: 200px;
    border-radius: 0.55rem;
    padding: 7px 10px;
}

.page-professor.professor-reimagined .asset-name {
    font-size: 0.78rem;
}

.page-professor.professor-reimagined .asset-origin,
.page-professor.professor-reimagined .asset-status {
    font-size: 0.68rem;
}

@keyframes professor-reimagined-enter-up {
    from {
        opacity: 0;
        transform: translateY(16px) scale(0.99);
    }

    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.page-professor.professor-reimagined .preview-header {
    align-items: center;
    gap: 10px;
    margin-bottom: 14px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--prof-border);
}

.page-professor.professor-reimagined .preview-title {
    font-size: 0.95rem;
    color: #1e293b;
}

.page-professor.professor-reimagined .preview-subtitle {
    font-size: 0.78rem;
    color: #94a3b8;
    margin-top: 2px;
}

.page-professor.professor-reimagined .preview-chip {
    padding: 3px 10px;
    border-radius: 999px;
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    color: #14b8a6;
    background: #f0fdfa;
    border: 1px solid rgba(20,184,166,0.25);
    text-align: center;
    min-width: 36px;
    text-transform: lowercase;
}

.page-professor.professor-reimagined .preview-actions {
    display: flex;
    gap: 6px;
}

.page-professor.professor-reimagined .preview-btn {
    padding: 5px 10px;
    border: 1px solid var(--prof-border);
    border-radius: 0.35rem;
    background: #ffffff;
    color: #94a3b8;
    font-size: 0.75rem;
    cursor: pointer;
    transition: all 150ms ease;
    font-family: inherit;
}

.page-professor.professor-reimagined .preview-btn:hover {
    background: #14b8a6;
    color: #fff;
    border-color: #14b8a6;
}

.page-professor.professor-reimagined .preview-btn.danger {
    background: #fff5f5;
    border-color: #fecaca;
    color: #dc2626;
}

.page-professor.professor-reimagined .preview-btn.danger:hover {
    background: #dc2626;
    border-color: #dc2626;
    color: #fff;
}

.page-professor.professor-reimagined .preview-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.page-professor.professor-reimagined .preview-body {
    flex: 1;
}

.page-professor.professor-reimagined .preview-section-title {
    font-size: 0.75rem;
    font-weight: 700;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
    margin-top: 12px;
}

.page-professor.professor-reimagined .preview-section-title:first-child {
    margin-top: 0;
}

.page-professor.professor-reimagined .linked-assets-strip {
    margin-bottom: 8px;
}

.page-professor.professor-reimagined .linked-assets-title-bar {
    display: block;
    width: 100%;
    margin-bottom: 8px;
    padding: 8px 10px;
    border: 1px solid var(--prof-border);
    border-radius: 0.35rem;
    background: #f8fafc;
    font-size: 0.78rem;
    font-weight: 600;
    color: #64748b;
    font-family: inherit;
}

.page-professor.professor-reimagined .preview-code {
    background: #1e293b;
    color: #e2e8f0;
    border: none;
    border-radius: 0.6rem;
    padding: 1.25rem;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.82rem;
    line-height: 1.6;
    overflow: auto;
    max-height: 380px;
    white-space: pre-wrap;
    word-break: break-word;
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.2);
}

.page-professor.professor-reimagined .time-pill-group {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.2rem;
}

.page-professor.professor-reimagined .time-pill {
    padding: 0.45rem 0.65rem;
    border-radius: 999px;
    border: 1px solid var(--prof-border);
    background: #ffffff;
    color: var(--prof-text);
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 160ms ease;
    flex: 0 1 auto;
    max-width: 100px;
    text-align: center;
    white-space: nowrap;
}

.page-professor.professor-reimagined .time-pill:hover {
    border-color: #94a3b8;
}

.page-professor.professor-reimagined .time-pill.active {
    background: #14b8a6;
    color: #ffffff;
    border-color: #14b8a6;
    box-shadow: 0 4px 12px rgba(20, 184, 166, 0.25);
}

.page-professor.professor-reimagined .time-pill-hint {
    display: block;
}

.page-professor.professor-reimagined .slide-list-empty {
    padding: 1.45rem 1rem;
    color: #94a3b8;
    font-size: 0.81rem;
    margin: 0;
    text-align: center;
}

.page-professor.professor-reimagined #openPresentationBtn {
    min-height: 50px;
    font-size: 0.98rem;
    font-weight: 700;
    letter-spacing: 0.01em;
    box-shadow: 0 10px 24px rgba(20, 184, 166, 0.2);
}

.page-professor.professor-reimagined #openPresentationBtn:disabled {
    box-shadow: none;
}

.page-professor.professor-reimagined .presentation-info,
.page-professor.professor-reimagined .presentation-error {
    border-radius: 1rem;
}

@media (max-width: 960px) {
    .page-professor.professor-reimagined .main-content {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .page-professor.professor-reimagined .global-settings {
        position: static;
    }
}

@media (max-width: 720px) {
    .page-professor.professor-reimagined .hero-header-inner {
        min-height: auto;
        padding-bottom: 3.25rem;
        grid-template-columns: 1fr auto;
        grid-template-areas:
            "home controls"
            "title title"
            "subtitle subtitle";
    }

    .page-professor.professor-reimagined .hero-brand {
        font-size: clamp(1.9rem, 8vw, 2.4rem);
    }

    .page-professor.professor-reimagined .slide-add-row .input-group {
        grid-template-columns: 1fr;
    }

    .page-professor.professor-reimagined .slide-add-row .input-group input[type="text"]:first-child {
        border-radius: 1rem !important;
        border-right: 1px solid var(--prof-border) !important;
    }

    .page-professor.professor-reimagined .slide-add-row .input-group input[type="text"]:nth-child(2) {
        border-radius: 1rem !important;
        border-left: 1px solid var(--prof-border) !important;
        border-right: 1px solid var(--prof-border) !important;
    }

    .page-professor.professor-reimagined .slide-add-row .input-group button#addMessageBtn {
        width: 100%;
        border-radius: 1rem !important;
    }
}

/* ========== Professor Dark Mode ========== */
html[data-theme="dark"] .page-professor.professor-reimagined {
    /* --- Elevation system (3-step, all teal-tinted) --- */
    --prof-surface: #122826;          /* card/panel — 1.22:1 vs #071311, exceeds perceptual threshold */
    --prof-surface-soft: #1c3835;     /* hover/raised elements — visibly lighter than surface */
    --prof-text: var(--color-text, #e8fffb);
    --prof-text-muted: #8db5ae;       /* 5.2:1 on elevated surfaces — WCAG AA safe */
    --prof-border: var(--color-border, #21413d);
    --prof-border-soft: rgba(45, 212, 191, 0.12);
    --prof-focus: rgba(45, 212, 191, 0.35);
    --prof-shadow-1: 0 4px 16px rgba(0, 0, 0, 0.45);
    --prof-shadow-2: 0 10px 28px rgba(0, 0, 0, 0.55);
    background:
        radial-gradient(circle at 8% 10%, rgba(45, 212, 191, 0.06), transparent 30%),
        radial-gradient(circle at 90% 20%, rgba(20, 184, 166, 0.04), transparent 25%),
        linear-gradient(180deg, var(--color-background, #071311) 0%, var(--color-background-alt, #0c1b19) 100%);
    color: var(--prof-text);
    color-scheme: dark;
}

/* --- Outer panel containers (white gradient by default) --- */
html[data-theme="dark"] .page-professor.professor-reimagined .global-settings,
html[data-theme="dark"] .page-professor.professor-reimagined .presentation-builder {
    background: linear-gradient(180deg, var(--prof-surface) 0%, #0e201e 100%);
    border-color: var(--prof-border);
}

/* --- Settings groups (inner cards on the left panel) --- */
html[data-theme="dark"] .page-professor.professor-reimagined .settings-group {
    background: var(--prof-surface-soft);
}

html[data-theme="dark"] .page-professor.professor-reimagined .settings-group:hover {
    background: #223f3c;
}

html[data-theme="dark"] .page-professor.professor-reimagined .settings-group-title {
    color: var(--color-primary, #2dd4bf);
}

/* --- Form inputs — inset well (darker than card = recessed) --- */
html[data-theme="dark"] .page-professor.professor-reimagined input[type="text"],
html[data-theme="dark"] .page-professor.professor-reimagined input[type="email"],
html[data-theme="dark"] .page-professor.professor-reimagined input[type="number"] {
    background: var(--color-background, #071311);
    color: var(--prof-text);
    border-color: rgba(45, 212, 191, 0.20);
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.45);
}

html[data-theme="dark"] .page-professor.professor-reimagined input[type="text"]:focus,
html[data-theme="dark"] .page-professor.professor-reimagined input[type="email"]:focus,
html[data-theme="dark"] .page-professor.professor-reimagined input[type="number"]:focus {
    background: var(--color-background, #071311);
    border-color: rgba(45, 212, 191, 0.55);
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.45), 0 0 0 3px var(--prof-focus);
}

html[data-theme="dark"] .page-professor.professor-reimagined input::placeholder {
    color: var(--prof-text-muted);
}

/* --- Upload dropzone — elevated affordance, clear target --- */
html[data-theme="dark"] .page-professor.professor-reimagined .upload-dropzone-large {
    background: var(--prof-surface-soft);
    border-color: rgba(45, 212, 191, 0.45);
}

html[data-theme="dark"] .page-professor.professor-reimagined .upload-dropzone-large:hover,
html[data-theme="dark"] .page-professor.professor-reimagined .upload-dropzone-large:focus-within,
html[data-theme="dark"] .page-professor.professor-reimagined .upload-dropzone-large.is-dragover {
    background: rgba(45, 212, 191, 0.10);
    border-color: rgba(45, 212, 191, 0.70);
    box-shadow: inset 0 0 0 1px rgba(45, 212, 191, 0.20);
}

html[data-theme="dark"] .page-professor.professor-reimagined .upload-dropzone-icon {
    color: var(--color-primary);
}

html[data-theme="dark"] .page-professor.professor-reimagined .upload-section-note {
    color: rgba(172, 215, 207, 0.65);
}

/* --- Buttons --- */
html[data-theme="dark"] .page-professor.professor-reimagined #addMessageBtn {
    background: rgba(56, 189, 248, 0.12);
    color: #bae6fd;
    border-color: rgba(56, 189, 248, 0.28);
}

html[data-theme="dark"] .page-professor.professor-reimagined #addMessageBtn:hover {
    background: rgba(56, 189, 248, 0.20);
    border-color: rgba(56, 189, 248, 0.40);
}

html[data-theme="dark"] .page-professor.professor-reimagined #openPresentationBtn:disabled {
    background: rgba(45, 212, 191, 0.12);
    color: var(--prof-text-muted);
    box-shadow: none;
}

/* --- Slide list area --- */
html[data-theme="dark"] .page-professor.professor-reimagined .slide-add-row {
    background: var(--prof-surface-soft);
}

html[data-theme="dark"] .page-professor.professor-reimagined .slide-list {
    border-color: var(--prof-border);
    background: var(--prof-surface);
}

html[data-theme="dark"] .page-professor.professor-reimagined .slide-list-empty {
    color: var(--prof-text-muted);
    border: 1.5px dashed rgba(45, 212, 191, 0.15);
    border-radius: 12px;
    padding: 2rem;
    margin: 0.5rem;
}

/* --- Split sidebar & preview panel --- */
html[data-theme="dark"] .page-professor.professor-reimagined .split-sidebar {
    background: linear-gradient(180deg, var(--prof-surface) 0%, var(--prof-surface-soft) 100%);
}

html[data-theme="dark"] .page-professor.professor-reimagined .mini-num {
    background: var(--prof-surface-soft);
    color: var(--color-primary);
}

html[data-theme="dark"] .page-professor.professor-reimagined .split-preview {
    background: linear-gradient(180deg, var(--prof-surface-soft) 0%, var(--color-surface-interactive, #16302d) 100%);
    border-color: var(--prof-border);
    box-shadow: -4px 0 16px rgba(0, 0, 0, 0.3);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-title {
    color: var(--prof-text);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-subtitle {
    color: var(--prof-text-muted);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-chip {
    color: var(--color-primary);
    background: rgba(45, 212, 191, 0.12);
    border-color: rgba(45, 212, 191, 0.25);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-btn {
    background: var(--prof-surface-soft);
    color: var(--prof-text-muted);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-btn:hover:not(.danger):not(:disabled) {
    background: rgba(45, 212, 191, 0.18);
    color: #2dd4bf;
    border-color: rgba(45, 212, 191, 0.40);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-btn.danger {
    background: rgba(251, 113, 133, 0.10);
    border-color: rgba(251, 113, 133, 0.30);
    color: #fb7185;
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-section-title {
    color: var(--prof-text-muted);
}

html[data-theme="dark"] .page-professor.professor-reimagined .linked-assets-title-bar {
    background: var(--prof-surface);
    color: var(--prof-text-muted);
}

/* --- Image cards inside preview panel --- */
html[data-theme="dark"] .page-professor.professor-reimagined .preview-image-card {
    background: var(--prof-surface);
    border-color: var(--prof-border-soft);
}

html[data-theme="dark"] .page-professor.professor-reimagined .preview-image {
    background: var(--prof-surface);
}

/* --- Hover tooltip preview popup --- */
html[data-theme="dark"] .page-professor.professor-reimagined .asset-hover-preview {
    background: var(--prof-surface-soft);
    border-color: var(--prof-border);
}

html[data-theme="dark"] .page-professor.professor-reimagined .asset-hover-preview-image {
    background: var(--prof-surface-soft);
}

/* --- Sidebar thumbnail backgrounds --- */
html[data-theme="dark"] .page-professor.professor-reimagined .asset-thumb-image {
    background: var(--prof-surface-soft);
    border-color: var(--prof-border-soft);
}

/* --- Time pills --- */
html[data-theme="dark"] .page-professor.professor-reimagined .time-pill {
    background: var(--prof-surface-soft);
    color: var(--prof-text-muted);
    border-color: var(--prof-border);
}

html[data-theme="dark"] .page-professor.professor-reimagined .time-pill:hover {
    border-color: rgba(45, 212, 191, 0.50);
    color: var(--prof-text);
}

html[data-theme="dark"] .page-professor.professor-reimagined .time-pill.active {
    background: rgba(45, 212, 191, 0.18);
    border-color: rgba(45, 212, 191, 0.55);
    color: #2dd4bf;
    box-shadow: 0 2px 8px rgba(45, 212, 191, 0.18);
}