:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary-color: #7c3aed;
    --accent-color: #ef4444;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --light-color: #f8fafc;
    --dark-color: #1e293b;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --border-radius-sm: 8px;
    --border-radius-md: 12px;
    --border-radius-lg: 16px;
    --transition: 300ms ease;
}

/* Default: show desktop layout, hide mobile layout */
.desktop-nivel-layout {
    display: block;
}

.mobile-nivel-layout {
    display: none;
}

@media (max-width: 768px) {
    /* On small screens, hide desktop and show mobile */
    .desktop-nivel-layout {
        display: none;
    }

    .mobile-nivel-layout {
        display: block;
    }

    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
        -webkit-tap-highlight-color: transparent;
    }

    html {
        font-size: 16px;
        scroll-behavior: smooth;
    }

    body {
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
        background: var(--light-color);
        color: var(--dark-color);
        line-height: 1.6;
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
    }

    /* Mobile Header */
    .mobile-test-header {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        height: 60px;
        background: white;
        backdrop-filter: blur(10px);
        box-shadow: var(--shadow-sm);
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 0 16px;
        z-index: 1000;
        border-bottom: 1px solid var(--gray-200);
    }

    .mobile-header-left {
        display: flex;
        align-items: center;
        gap: 12px;
    }

    .mobile-back-btn {
        width: 44px;
        height: 44px;
        border-radius: var(--border-radius-sm);
        border: none;
        background: var(--gray-100);
        color: var(--dark-color);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.2rem;
        cursor: pointer;
        text-decoration: none;
    }

    .mobile-header-logo {
        height: 32px;
        width: auto;
    }

    .mobile-header-title {
        font-size: 1.125rem;
        font-weight: 700;
        color: var(--dark-color);
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
        max-width: 150px;
    }

    .mobile-language-btn {
        width: 44px;
        height: 44px;
        border-radius: var(--border-radius-sm);
        border: none;
        background: var(--gray-100);
        color: var(--dark-color);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.2rem;
        cursor: pointer;
    }

    /* Main Content */
    .mobile-test-content {
        margin-top: 80px;
        padding: 0 16px 80px;
        max-width: 800px;
        margin-left: auto;
        margin-right: auto;
    }

    /* Instructions Section */
    .mobile-instructions-section {
        background: white;
        border-radius: var(--border-radius-lg);
        padding: 24px;
        margin: 20px 0;
        box-shadow: var(--shadow-md);
    }

    .mobile-section-title {
        font-size: 1.5rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 16px;
        display: flex;
        align-items: center;
        gap: 10px;
    }

    .mobile-section-title i {
        color: var(--primary-color);
    }

    .mobile-instructions-description {
        font-size: 1rem;
        color: var(--gray-600);
        margin-bottom: 24px;
        line-height: 1.6;
    }

    .mobile-instructions-list {
        display: flex;
        flex-direction: column;
        gap: 20px;
    }

    .mobile-instruction-item {
        display: flex;
        align-items: flex-start;
        gap: 16px;
        padding: 16px;
        background: var(--gray-100);
        border-radius: var(--border-radius-md);
        border-left: 4px solid var(--primary-color);
    }

    .mobile-instruction-icon {
        width: 48px;
        height: 48px;
        background: white;
        border-radius: var(--border-radius-sm);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem;
        color: var(--primary-color);
        flex-shrink: 0;
    }

    .mobile-instruction-content h4 {
        font-size: 1.125rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 4px;
    }

    .mobile-instruction-content p {
        font-size: 0.95rem;
        color: var(--gray-600);
        line-height: 1.5;
    }

    /* Test Area */
    .mobile-test-area {
        background: white;
        border-radius: var(--border-radius-lg);
        overflow: hidden;
        box-shadow: var(--shadow-lg);
        margin: 24px 0;
    }

    /* Test Header */
    .mobile-test-header-section {
        background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
        color: white;
        padding: 20px;
    }

    .mobile-test-title {
        font-size: 1.5rem;
        font-weight: 700;
        margin-bottom: 4px;
    }

    .mobile-test-subtitle {
        font-size: 0.95rem;
        opacity: 0.9;
        margin-bottom: 16px;
    }

    .mobile-test-info {
        display: flex;
        gap: 20px;
        margin-bottom: 16px;
        flex-wrap: wrap;
    }

    .mobile-test-info-item {
        display: flex;
        align-items: center;
        gap: 8px;
        font-size: 0.9rem;
    }

    .mobile-test-info-item i {
        font-size: 1.1rem;
    }

    .mobile-test-progress {
        background: rgba(255, 255, 255, 0.2);
        border-radius: var(--border-radius-sm);
        padding: 12px;
        backdrop-filter: blur(10px);
    }

    .mobile-progress-header {
        display: flex;
        justify-content: space-between;
        color: white;
        font-size: 0.9rem;
        margin-bottom: 8px;
    }

    .mobile-progress-bar {
        height: 8px;
        background: rgba(255, 255, 255, 0.3);
        border-radius: 4px;
        overflow: hidden;
    }

    .mobile-progress-fill {
        height: 100%;
        background: white;
        border-radius: 4px;
        transition: width var(--transition);
    }

    /* Test Body */
    .mobile-test-body {
        padding: 0;
    }

    /* Start Screen */
    .mobile-start-screen {
        padding: 40px 24px;
        text-align: center;
    }

    .mobile-start-icon {
        width: 80px;
        height: 80px;
        background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        margin: 0 auto 24px;
        color: white;
        font-size: 2.5rem;
    }

    .mobile-start-title {
        font-size: 1.5rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 12px;
    }

    .mobile-start-description {
        font-size: 1rem;
        color: var(--gray-600);
        margin-bottom: 32px;
        line-height: 1.6;
    }

    .mobile-test-type-selector {
        display: flex;
        flex-direction: column;
        gap: 16px;
        margin-bottom: 32px;
    }

    .mobile-test-type-card {
        background: var(--gray-100);
        border-radius: var(--border-radius-md);
        padding: 20px;
        text-align: left;
        cursor: pointer;
        border: 2px solid transparent;
        transition: all var(--transition);
        user-select: none;
    }

    .mobile-test-type-card:active {
        transform: scale(0.98);
    }

    .mobile-test-type-card.selected {
        border-color: var(--primary-color);
        background: rgba(37, 99, 235, 0.05);
    }

    .mobile-test-type-header {
        display: flex;
        align-items: center;
        gap: 12px;
        margin-bottom: 12px;
    }

    .mobile-test-type-icon {
        width: 48px;
        height: 48px;
        background: white;
        border-radius: var(--border-radius-sm);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem;
        color: var(--primary-color);
    }

    .mobile-test-type-content h3 {
        font-size: 1.125rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 4px;
    }

    .mobile-test-type-meta {
        font-size: 0.9rem;
        color: var(--gray-600);
        margin-bottom: 8px;
    }

    .mobile-test-type-hint {
        font-size: 0.9rem;
        color: var(--gray-500);
        font-style: italic;
    }

    /* Questions Container */
    .mobile-questions-container {
        padding: 24px;
    }

    .mobile-question-card {
        display: none;
    }

    .mobile-question-card.active {
        display: block;
    }

    .mobile-question-header {
        margin-bottom: 24px;
    }

    .mobile-question-title {
        font-size: 1.125rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 12px;
    }

    .mobile-question-text {
        font-size: 1rem;
        color: var(--gray-700);
        line-height: 1.6;
    }

    .mobile-audio-player {
        margin: 20px 0;
        padding: 16px;
        background: var(--gray-100);
        border-radius: var(--border-radius-md);
        text-align: center;
    }

    .mobile-audio-player button {
        width: 56px;
        height: 56px;
        border-radius: 50%;
        border: none;
        background: var(--primary-color);
        color: white;
        font-size: 1.5rem;
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: center;
        margin: 0 auto 12px;
    }

    .mobile-audio-player button:active {
        transform: scale(0.95);
    }

    .mobile-options-list {
        display: flex;
        flex-direction: column;
        gap: 12px;
        margin-bottom: 24px;
    }

    .mobile-option-item {
        padding: 16px;
        background: var(--gray-100);
        border-radius: var(--border-radius-sm);
        cursor: pointer;
        transition: all var(--transition);
        border: 2px solid transparent;
        user-select: none;
    }

    .mobile-option-item:active {
        transform: scale(0.98);
    }

    .mobile-option-item.selected {
        border-color: var(--primary-color);
        background: rgba(37, 99, 235, 0.05);
    }

    .mobile-option-item.correct {
        border-color: var(--success-color);
        background: rgba(16, 185, 129, 0.05);
    }

    .mobile-option-item.incorrect {
        border-color: var(--accent-color);
        background: rgba(239, 68, 68, 0.05);
    }

    .mobile-option-text {
        font-size: 1rem;
        color: var(--dark-color);
    }

    .mobile-option-letter {
        display: inline-block;
        width: 24px;
        height: 24px;
        background: var(--gray-300);
        border-radius: 50%;
        text-align: center;
        line-height: 24px;
        margin-right: 12px;
        font-weight: 600;
        color: var(--dark-color);
    }

    .mobile-question-actions {
        display: flex;
        gap: 12px;
    }

    .mobile-btn {
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 8px;
        width: 100%;
        padding: 16px 24px;
        border: none;
        border-radius: var(--border-radius-sm);
        font-size: 1rem;
        font-weight: 600;
        cursor: pointer;
        transition: all var(--transition);
        text-decoration: none;
        text-align: center;
    }

    .mobile-btn-primary {
        background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
        color: white;
    }

    .mobile-btn-primary:active {
        transform: scale(0.98);
        background: var(--primary-dark);
    }

    .mobile-btn-secondary {
        background: white;
        color: var(--primary-color);
        border: 2px solid var(--primary-color);
    }

    .mobile-btn-secondary:active {
        background: var(--gray-100);
    }

    .mobile-btn-disabled {
        opacity: 0.5;
        cursor: not-allowed;
    }

    .mobile-btn-disabled:active {
        transform: none;
    }

    /* Timer */
    .mobile-timer {
        position: fixed;
        top: 70px;
        right: 16px;
        background: var(--accent-color);
        color: white;
        padding: 8px 16px;
        border-radius: var(--border-radius-sm);
        font-size: 0.9rem;
        font-weight: 600;
        display: none;
        z-index: 999;
        box-shadow: var(--shadow-md);
    }

    .mobile-timer.warning {
        background: var(--warning-color);
    }

    /* Results Container */
    .mobile-results-container {
        padding: 40px 24px;
        text-align: center;
        display: none;
    }

    .mobile-results-icon {
        width: 80px;
        height: 80px;
        background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        margin: 0 auto 24px;
        color: white;
        font-size: 2.5rem;
    }

    .mobile-results-level {
        font-size: 2rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 12px;
    }

    .mobile-results-description {
        font-size: 1rem;
        color: var(--gray-600);
        margin-bottom: 32px;
        line-height: 1.6;
    }

    .mobile-results-details {
        background: var(--gray-100);
        border-radius: var(--border-radius-md);
        padding: 24px;
        margin-bottom: 32px;
        text-align: left;
    }

    .mobile-results-details h3 {
        font-size: 1.25rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 16px;
    }

    .mobile-level-info {
        display: flex;
        flex-direction: column;
        gap: 20px;
    }

    .mobile-level-item {
        padding: 16px;
        background: white;
        border-radius: var(--border-radius-sm);
    }

    .mobile-level-item h4 {
        font-size: 1.125rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 8px;
    }

    .mobile-level-item p {
        font-size: 1rem;
        color: var(--gray-600);
        margin-bottom: 8px;
    }

    .mobile-level-item .score {
        font-size: 1.5rem;
        font-weight: 700;
        color: var(--primary-color);
    }

    .mobile-results-actions {
        display: flex;
        flex-direction: column;
        gap: 12px;
    }

    /* Footer */
    .mobile-test-footer {
        background: var(--dark-color);
        color: white;
        padding: 40px 16px 60px;
        margin-top: 40px;
    }

    .mobile-footer-content {
        display: flex;
        flex-direction: column;
        gap: 32px;
    }

    .mobile-footer-section {
        flex: 1;
    }

    .mobile-footer-title {
        font-size: 1.125rem;
        font-weight: 700;
        margin-bottom: 16px;
        color: white;
    }

    .mobile-footer-logo {
        width: 120px;
        height: auto;
        margin-bottom: 16px;
    }

    .mobile-footer-text {
        font-size: 0.95rem;
        opacity: 0.8;
        margin-bottom: 20px;
        line-height: 1.5;
    }

    .mobile-footer-social {
        display: flex;
        gap: 12px;
    }

    .mobile-footer-social a {
        width: 40px;
        height: 40px;
        border-radius: 50%;
        background: rgba(255, 255, 255, 0.1);
        display: flex;
        align-items: center;
        justify-content: center;
        color: white;
        text-decoration: none;
        transition: all var(--transition);
    }

    .mobile-footer-social a:active {
        background: var(--primary-color);
        transform: scale(0.95);
    }

    .mobile-footer-links {
        list-style: none;
    }

    .mobile-footer-links li {
        margin-bottom: 12px;
    }

    .mobile-footer-links a {
        color: rgba(255, 255, 255, 0.8);
        text-decoration: none;
        font-size: 0.95rem;
        transition: all var(--transition);
        display: flex;
        align-items: center;
        gap: 8px;
    }

    .mobile-footer-links a:active {
        color: white;
        transform: translateX(5px);
    }

    .mobile-footer-contact {
        list-style: none;
    }

    .mobile-footer-contact li {
        margin-bottom: 12px;
        display: flex;
        align-items: flex-start;
        gap: 12px;
        font-size: 0.95rem;
        opacity: 0.8;
    }

    .mobile-footer-contact i {
        color: var(--primary-color);
        margin-top: 2px;
    }

    .mobile-footer-copyright {
        text-align: center;
        padding-top: 24px;
        margin-top: 32px;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
        font-size: 0.875rem;
        opacity: 0.6;
    }

    /* Bottom Navigation */
    .mobile-bottom-nav {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        height: 60px;
        background: white;
        border-top: 1px solid var(--gray-200);
        display: flex;
        justify-content: space-around;
        align-items: center;
        z-index: 1000;
        padding-bottom: env(safe-area-inset-bottom);
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    }

    .mobile-nav-item {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        text-decoration: none;
        color: var(--gray-500);
        font-size: 0.75rem;
        gap: 4px;
        flex: 1;
        height: 100%;
        background: none;
        border: none;
        cursor: pointer;
    }

    .mobile-nav-item i {
        font-size: 1.25rem;
    }

    .mobile-nav-item.active {
        color: var(--primary-color);
    }

    .mobile-nav-item.active i {
        color: var(--primary-color);
    }

    /* Dropdown de usuario en la barra inferior */
    .mobile-user-dropdown {
        position: fixed;
        left: 50%;
        bottom: 72px;
        transform: translateX(-50%);
        background: #ffffff;
        border-radius: 12px;
        box-shadow: 0 12px 25px rgba(15, 23, 42, 0.35);
        padding: 6px 0;
        min-width: 200px;
        z-index: 1100;
        display: none;
    }

    .mobile-user-dropdown.active {
        display: block;
    }

    .mobile-user-dropdown-item {
        width: 100%;
        padding: 10px 18px;
        text-align: left;
        background: transparent;
        border: none;
        font-size: 0.9rem;
        color: var(--dark-color);
        cursor: pointer;
    }

    .mobile-user-dropdown-item + .mobile-user-dropdown-item {
        border-top: 1px solid #e2e8f0;
    }

    .mobile-user-dropdown-item:active {
        background: #eff6ff;
    }

    /* Modal */
    .mobile-modal-overlay {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.5);
        z-index: 2000;
        display: flex;
        align-items: center;
        justify-content: center;
        padding: 20px;
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition);
    }

    .mobile-modal-overlay.active {
        opacity: 1;
        visibility: visible;
    }

    .mobile-modal-content {
        background: white;
        border-radius: var(--border-radius-lg);
        padding: 24px;
        width: 100%;
        max-width: 400px;
        transform: translateY(20px);
        transition: transform var(--transition);
    }

    .mobile-modal-overlay.active .mobile-modal-content {
        transform: translateY(0);
    }

    /* Modal genérico tipo index (contenedor flex) */
    .mobile-modal {
        position: fixed;
        inset: 0;
        display: none;
        align-items: center;
        justify-content: center;
        z-index: 2050;
    }

    .mobile-modal.active {
        display: flex;
    }

    .mobile-language-options {
        display: flex;
        flex-direction: column;
        gap: 8px;
    }

    .mobile-language-option {
        padding: 16px;
        border: 2px solid var(--gray-200);
        border-radius: var(--border-radius-sm);
        background: white;
        font-size: 1rem;
        font-weight: 600;
        color: var(--gray-700);
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: space-between;
        transition: all var(--transition);
    }

    .mobile-language-option.active {
        border-color: var(--primary-color);
        background: var(--primary-color);
        color: white;
    }

    .mobile-language-option:active {
        transform: scale(0.98);
    }

    /* Toast */
    .mobile-toast {
        position: fixed;
        bottom: 80px;
        left: 20px;
        right: 20px;
        background: var(--dark-color);
        color: white;
        padding: 16px;
        border-radius: var(--border-radius-sm);
        text-align: center;
        z-index: 3000;
        transform: translateY(100px);
        opacity: 0;
        transition: all var(--transition);
    }

    .mobile-toast.show {
        transform: translateY(0);
        opacity: 1;
    }

    .mobile-toast.success {
        background: var(--success-color);
    }

    .mobile-toast.error {
        background: var(--accent-color);
    }

    .mobile-toast.warning {
        background: var(--warning-color);
    }

    /* Utility */
    .hidden {
        display: none !important;
    }

    .text-center {
        text-align: center;
    }

    .mb-1 { margin-bottom: 4px; }
    .mb-2 { margin-bottom: 8px; }
    .mb-3 { margin-bottom: 12px; }
    .mb-4 { margin-bottom: 16px; }
    .mb-5 { margin-bottom: 20px; }
    .mb-6 { margin-bottom: 24px; }

    .mt-1 { margin-top: 4px; }
    .mt-2 { margin-top: 8px; }
    .mt-3 { margin-top: 12px; }
    .mt-4 { margin-top: 16px; }
    .mt-5 { margin-top: 20px; }
    .mt-6 { margin-top: 24px; }

    /* Simple helpers used in markup */
    .p-3 { padding: 12px; }
    .bg-gray-50 { background: #f9fafb; }
    .rounded-md { border-radius: var(--border-radius-md); }

    /* Responsive tweaks */
    @media (min-width: 768px) {
        .mobile-test-content {
            padding: 0 24px 80px;
        }

        .mobile-test-type-selector {
            flex-direction: row;
            flex-wrap: wrap;
        }

        .mobile-test-type-card {
            flex: 1;
            min-width: 200px;
        }

        .mobile-questions-container {
            padding: 32px;
        }

        .mobile-question-actions {
            flex-direction: row;
        }

        .mobile-btn {
            width: auto;
            min-width: 150px;
        }

        .mobile-results-actions {
            flex-direction: row;
            justify-content: center;
        }

        .mobile-footer-content {
            flex-direction: row;
            flex-wrap: wrap;
        }

        .mobile-footer-section {
            flex: 1;
            min-width: 250px;
        }
    }
}