/* ==============================
           BOOKS GRID
        ============================== */
        .library-header {
            margin-bottom: var(--space-xl);
        }

        .library-title {
            font-size: var(--text-2xl);
            font-weight: 800;
            color: var(--text);
            margin-bottom: var(--space-xs);
            letter-spacing: -0.02em;
        }

        .library-subtitle {
            font-size: var(--text-sm);
            color: var(--text-secondary);
            font-weight: 500;
        }

        .books-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: var(--space-sm);
            margin-bottom: var(--space-xl);
        }

        .book-btn {
            padding: var(--space-md);
            border-radius: var(--radius-md);
            border: 1px solid var(--border);
            background: var(--surface);
            color: var(--text);
            font-weight: 600;
            text-align: left;
            cursor: pointer;
            transition: all 0.25s var(--ease-standard);
            font-family: var(--font-main);
            font-size: var(--text-base);
            line-height: 1.3;
            position: relative;
            overflow: hidden;
            display: flex;
            align-items: center;
            gap: var(--space-sm);
            min-height: 56px;
        }

        .book-btn:hover {
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
            border-color: var(--primary);
        }

        .book-btn:active {
            transform: scale(0.97);
        }

        .book-btn-icon {
            width: 34px;
            height: 34px;
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            z-index: 1;
            transition: transform 0.3s var(--ease-spring);
        }

        .book-btn:hover .book-btn-icon {
            transform: scale(1.08) rotate(-3deg);
        }

        .book-btn-icon .material-icons-round {
            font-size: 18px;
        }

        .vt-icon {
            background: var(--primary-light);
            color: var(--primary);
        }

        .nt-icon {
            background: rgba(59, 130, 246, 0.08);
            color: #3b82f6;
        }

        [data-theme="dark"] .nt-icon {
            background: rgba(96, 165, 250, 0.1);
            color: #60a5fa;
        }

        [data-theme="sepia"] .nt-icon {
            background: rgba(180, 120, 60, 0.1);
            color: #b4783c;
        }

        .book-btn-text {
            display: flex;
            flex-direction: column;
            min-width: 0;
            z-index: 1;
        }

        .book-btn-name {
            font-size: var(--text-sm);
            font-weight: 700;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .book-btn-chaps {
            font-size: var(--text-xs);
            color: var(--text-secondary);
            font-weight: 500;
            margin-top: 1px;
        }

        /* ==============================