/* tvls-seating.css — Sơ Đồ Chỗ Ngồi Styles */
        /* ======================== TAB 2: SƠ ĐỒ CHỖ NGỒI (TỐI ƯU DELL 15" KHÔNG KHUẤT CHỮ) ======================== */
        
        .btn-icon-only {
            width: 36px;
            height: 36px;
            min-width: 36px;
            padding: 0;
            font-size: 16px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            border-radius: 8px;
            flex-shrink: 0;
            cursor: pointer;
            transition: all 0.15s ease;
            box-sizing: border-box;
        }
        .btn-icon-only:hover {
            transform: translateY(-2px);
            box-shadow: 0 3px 8px rgba(0,0,0,0.12);
        }

        .seating-controls {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-bottom: 6px;
            flex-wrap: wrap;
            gap: 8px;
            background: rgba(241, 245, 249, 0.88);
            padding: 4px 8px;
            border-radius: 12px;
            border: 1px solid var(--border-color);
        }

        .swap-guide {
            display: flex;
            align-items: center;
            gap: 6px;
            font-size: 12px;
            font-weight: 700;
            color: #334155;
            flex-wrap: wrap;
        }

        .swap-guide .highlight-tag {
            background: #fef08a;
            color: #854d0e;
            padding: 2px 7px;
            border-radius: 5px;
            font-size: 11.5px;
        }

        .classroom-wrapper {
            background: rgba(255, 255, 255, 0.94);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border: 1.5px solid var(--border-card);
            border-radius: 12px;
            padding: 8px 10px;
            box-shadow: var(--shadow-card);
            position: relative;
            overflow-x: auto;
            -webkit-overflow-scrolling: touch;
        }

        .rows-container, .podium-area {
            min-width: 680px;
        }

        .double-desk {
            min-width: 140px;
        }

        .seat-card {
            min-width: 68px;
        }

        /* BỤC GIẢNG */
        .podium-area {
            display: grid;
            grid-template-columns: 1fr 2fr 1fr;
            align-items: center;
            gap: 12px;
            margin-bottom: 4px;
            padding-bottom: 4px;
            border-bottom: 1.5px dashed rgba(203, 213, 225, 0.8);
            width: 100%;
            box-sizing: border-box;
        }

        .podium-box {
            padding: 4px 12px;
            height: 32px;
            min-height: 32px;
            border-radius: 6px;
            text-align: center;
            font-family: var(--font-title);
            font-weight: 800;
            font-size: 12.5px;
            letter-spacing: 0.5px;
            transition: all 0.15s ease;
            cursor: pointer;
            user-select: none;
            position: relative;
            display: flex;
            align-items: center;
            justify-content: center;
            box-sizing: border-box;
        }

        .podium-box:nth-child(1) {
            justify-self: start;
        }

        .podium-box:nth-child(2) {
            justify-self: center;
        }

        .podium-box:nth-child(3) {
            justify-self: end;
        }

        .box-teacher {
            min-width: 160px;
            max-width: 210px;
            height: 32px;
            background: #fef3c7;
            border: 1.5px solid #f59e0b;
            color: #78350f;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            border-radius: 6px;
            font-size: 12px;
            padding: 0 10px;
            box-sizing: border-box;
        }

        .box-board {
            width: 100%;
            max-width: 100%;
            height: 32px;
            background: #1e293b;
            border: 1.5px solid #0f172a;
            color: #ffffff;
            box-shadow: 0 2px 5px rgba(0,0,0,0.15);
            font-size: 12.5px;
            letter-spacing: 3px;
            text-align: center;
            border-radius: 6px;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 0;
            box-sizing: border-box;
        }

        .box-door {
            width: 100%;
            max-width: 130px;
            height: 32px;
            background: #f8fafc;
            border: 1.5px dashed #64748b;
            border-radius: 6px;
            color: #1e293b;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            font-size: 11.5px;
            font-weight: 800;
            cursor: pointer;
            transition: all 0.15s ease;
            user-select: none;
            justify-self: start;
            box-shadow: 0 1px 3px rgba(0,0,0,0.06);
            box-sizing: border-box;
            padding: 0 8px;
        }
        .box-door:hover {
            background: #f1f5f9;
            border-color: #334155;
            transform: translateY(-2px);
            box-shadow: 0 4px 10px rgba(0,0,0,0.1);
        }

        .podium-box:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(0,0,0,0.12);
        }

        .podium-box.selected {
            border: 2.5px solid #1f4e79 !important;
            box-shadow: 0 0 0 4px rgba(31, 78, 121, 0.3) !important;
            animation: pulseSelect 1.5s infinite;
        }

        .podium-box.drag-over {
            background: #f0fdf4 !important;
            border: 2px dashed #10b981 !important;
            transform: scale(1.03);
        }

        .box-teacher {
            background: #fef3c7;
            border: 1.5px solid #f59e0b;
            color: #78350f;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
        }

        .box-board {
            background: #1e293b;
            border: 2px solid #0f172a;
            color: #ffffff;
            box-shadow: 0 4px 8px rgba(0,0,0,0.15);
            font-size: 14px;
            letter-spacing: 3px;
        }

        .box-door {
            background: #f1f5f9;
            border: 1.5px solid #94a3b8;
            color: #334155;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
        }

        /* TIÊU ĐỀ 4 DÃY BÀN & 3 LỐI ĐI */
        .aisle-header-row {
            display: grid;
            /* Cột Hàng (40px) | Dãy 1 (1fr) | Lối đi 1 (18px) | Dãy 2 (1fr) | Lối đi 2 (18px) | Dãy 3 (1fr) | Lối đi 3 (18px) | Dãy 4 (1fr) */
            grid-template-columns: 1fr 20px 1fr 20px 1fr 20px 1fr;
            gap: 6px;
            align-items: center;
            margin-bottom: 8px;
            text-align: center;
        }

        .aisle-col-title {
            background: #e8f1fa;
            color: #3730a3;
            font-family: var(--font-title);
            font-weight: 800;
            font-size: 12px;
            padding: 5px 8px;
            border-radius: 6px;
            border: 1px solid #c9dced;
            letter-spacing: 0.3px;
        }

        /* KHUNG CÁC HÀNG GHẾ */
        .rows-container {
            display: flex;
            flex-direction: column;
            gap: 5px;
        }

        .seating-row {
            display: grid;
            grid-template-columns: 1fr 22px 1fr 22px 1fr 22px 1fr;
            align-items: center;
            gap: 4px;
            background: rgba(248, 250, 252, 0.85);
            padding: 1px 4px;
            border-radius: 6px;
            border: 1px solid #e2e8f0;
        }

        .row-label {
            font-family: var(--font-title);
            font-weight: 800;
            font-size: 11.5px;
            color: #475569;
            text-align: center;
            background: #e2e8f0;
            padding: 10px 2px;
            border-radius: 6px;
            line-height: 1.15;
        }

        /* BÀN ĐÔI (MỖI BÀN 2 BẠN) */
        .double-desk {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 3px;
            background: #ffffff;
            padding: 3px;
            border-radius: 8px;
            border: 1.5px solid #cbd5e1;
            box-shadow: 0 1px 2px rgba(0,0,0,0.03);
            position: relative;
        }

        .double-desk::before {
            content: '';
            position: absolute;
            top: 4px;
            bottom: 4px;
            left: 50%;
            width: 1px;
            background: #e2e8f0;
        }

        /* KHOẢNG HỞ LỐI ĐI GIỮA CÁC DÃY */
        .aisle-spacer {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            font-size: 10px;
            font-weight: 800;
            color: #94a3b8;
            user-select: none;
            background: rgba(226, 232, 240, 0.4);
            border-radius: 4px;
            height: 100%;
        }

        .aisle-dots {
            display: flex;
            flex-direction: column;
            gap: 3px;
            align-items: center;
        }

        .aisle-dot {
            width: 3.5px;
            height: 3.5px;
            background: #94a3b8;
            border-radius: 50%;
        }

        /* THẺ GHẾ HỌC SINH (KHÔNG BỊ KHUẤT CHỮ TRÊN LAPTOP DELL 15") */
        .seat-card {
            border-radius: 8px;
            padding: 6px 8px;
            height: 56px;
            min-height: 56px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            text-align: center;
            cursor: pointer;
            user-select: none;
            transition: all 0.15s ease;
            position: relative;
            border: 1.5px solid transparent;
            box-sizing: border-box;
        }

        .seat-top-row {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 100%;
            position: relative;
            margin-top: 1px;
        }

        .seat-name {
            font-size: 13.5px;
            font-weight: 800;
            color: #0f172a;
            line-height: 1.2;
            text-align: center;
            white-space: normal;
            word-wrap: break-word;
            word-break: break-word;
            overflow-wrap: break-word;
            padding: 0 2px;
            letter-spacing: -0.2px;
            width: 100%;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .seat-star-btn {
            position: absolute;
            left: 0;
            top: 50%;
            transform: translateY(-50%);
            background: none;
            border: none;
            cursor: pointer;
            font-size: 10px;
            opacity: 0.7;
            padding: 0;
            line-height: 1;
            z-index: 5;
        }
        .seat-star-btn:hover {
            opacity: 1;
            transform: translateY(-50%) scale(1.2);
        }

        .seat-bottom-row {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
            height: 18px;
        }

        .seat-speak-count {
            font-size: 9.5px;
            font-weight: 800;
            background: #fef08a;
            color: #854d0e;
            padding: 1px 4px;
            border-radius: 4px;
            border: 1px solid #fde047;
            line-height: 1.1;
            display: inline-flex;
            align-items: center;
            gap: 2px;
            pointer-events: none;
        }

        .seat-speak-controls {
            display: flex;
            align-items: center;
            gap: 3px;
            margin-left: auto;
            flex-shrink: 0;
        }

        .btn-speak-minus, .btn-speak-plus {
            width: 22px;
            height: 20px;
            border-radius: 4px;
            font-size: 13px;
            font-weight: 800;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            background: #ffffff;
            transition: all 0.12s ease;
            line-height: 1;
            padding: 0;
            box-shadow: none;
        }

        .btn-speak-minus {
            border: 1px solid #f87171;
            color: #ef4444;
            background: #ffffff;
        }
        .btn-speak-minus:hover {
            background: #ef4444;
            border-color: #dc2626;
            color: #ffffff;
            transform: scale(1.1);
        }

        .btn-speak-plus {
            border: 1px solid #38bdf8;
            color: #0284c7;
            background: #ffffff;
        }
        .btn-speak-plus:hover {
            background: #0284c7;
            border-color: #0369a1;
            color: #ffffff;
            transform: scale(1.1);
        }

        /* Tô nền nhẹ & viền theo giới tính */
        .seat-card.card-nam {
            background: #e0f2fe;
            border-color: #7dd3fc;
        }

        .seat-card.card-nu {
            background: #fce7f3;
            border-color: #f472b6;
        }

        .seat-card:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 10px rgba(0,0,0,0.08);
            border-color: #6366f1;
        }

        .seat-card.selected {
            border: 2px solid #1f4e79 !important;
            background: #e0e7ff !important;
            box-shadow: 0 0 0 3px rgba(31, 78, 121, 0.3) !important;
            animation: pulseSelect 1.5s infinite;
        }

        @keyframes pulseSelect {
            0% { transform: scale(1); }
            50% { transform: scale(1.02); }
            100% { transform: scale(1); }
        }

        .seat-card.drag-over {
            background: #f0fdf4 !important;
            border: 2px dashed #10b981 !important;
            transform: scale(1.02);
        }

        .seat-card.empty {
            background: #f8fafc;
            border: 1.5px dashed #cbd5e1;
            color: #94a3b8;
            align-items: center;
            justify-content: center;
            min-height: 60px;
        }

        /* Đã bỏ mô tả D4-T */

        .seat-avatar-badge {
            display: flex;
            align-items: center;
            gap: 3px;
        }

        .avatar-icon {
            font-size: 11px;
            line-height: 1;
        }

        .stt-badge {
            font-size: 9px;
            font-weight: 800;
            width: 14px;
            height: 14px;
            border-radius: 4px;
            display: flex;
            align-items: center;
            justify-content: center;
            line-height: 1;
        }

        .stt-nam {
            background: #e0f2fe;
            color: #0369a1;
        }

        .stt-nu {
            background: #fce7f3;
            color: #be185d;
        }

        /* Tên học sinh hiển thị to rõ, không bị khuất chữ */
        .seat-name {
            font-size: 13.5px;
            font-weight: 800;
            color: #0f172a;
            line-height: 1.2;
            text-align: center;
            white-space: normal;
            word-wrap: break-word;
            word-break: break-word;
            overflow-wrap: break-word;
            margin: 2px 0;
            padding: 0 4px;
            letter-spacing: -0.2px;
            width: 100%;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        @keyframes tvlsSpin {
            0% { transform: rotate(0deg); }
            100% { transform: rotate(360deg); }
        }

        .seating-spinner {
            width: 36px;
            height: 36px;
            border: 3.5px solid #e2e8f0;
            border-top-color: var(--primary, #1f4e79);
            border-radius: 50%;
            animation: tvlsSpin 0.75s linear infinite;
        }