/* Móviles pequeños: hasta 400px */
@media (max-width: 400px) {
    .header {
        padding: 0.75rem 1rem;
        gap: 0.75rem;
    }

    .logo-text {
        font-size: 1.2rem;
    }

    .header-actions {
        width: auto;
        flex-direction: row;
        flex: 1;
        min-width: 0;
        gap: 0.75rem;
    }

    .header-search-row {
        width: auto;
        flex: 1;
        min-width: 0;
    }

    .header-search-row .search-bar {
        width: auto;
        flex: 1;
        min-width: 0;
    }

    .mobile-panel-toggle {
        display: inline-flex;
    }

    .search-bar {
        width: 100%;
    }

    .btn {
        width: 100%;
        padding: 0.6rem;
        font-size: 0.875rem;
    }

    .container {
        flex-direction: column;
    }

    .sidebar {
        display: none;
        width: 100%;
        height: auto;
        max-height: 200px;
        overflow-y: auto;
        border-right: none;
        border-bottom: 2px solid var(--cyan);
    }

    body.panel-open .sidebar {
        display: block;
    }

    .sidebar-section {
        margin-bottom: 1rem;
    }

    .workspace {
        padding: 1rem;
    }

    .workspace-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }

    .page-title {
        font-size: 1.5rem;
    }

    .toolbar {
        width: 100%;
        flex-wrap: wrap;
    }

    .tool-btn {
        flex: 1;
        min-width: calc(50% - 0.25rem);
    }

    .content-block {
        padding: 1rem;
    }

    .pdf-viewer {
        grid-template-columns: 1fr;
    }

    .pdf-display,
    .pdf-annotations {
        height: 300px;
    }
}