/* Complete CSS for Mock Test Application - Mobile First Responsive Design */

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
    width: 100%;
    height: 100%;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
    width: 100%;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Navigation Styles */
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    width: 100%;
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    color: white;
    text-decoration: none;
}

/* Desktop Navigation - Default */
.nav-links {
    display: flex;
    flex-direction: row;
    gap: 2rem;
    align-items: center;
}

.mobile-menu-toggle {
    display: none;
}

/* Mobile Navigation */
@media (max-width: 767px) {
    .mobile-menu-toggle {
        display: block;
        background: none;
        border: none;
        color: white;
        font-size: 1.5rem;
        cursor: pointer;
        padding: 0.5rem;
    }
    
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(0,0,0,0.95);
        z-index: 1000;
        border-radius: 0 0 8px 8px;
        box-shadow: 0 4px 12px rgba(0,0,0,0.3);
        flex-direction: column;
        padding: 1rem;
        margin-top: 0;
        width: 100%;
    }
    
    .nav-links.active {
        display: flex !important;
    }
    
    .nav-links a {
        padding: 12px 20px;
        border-bottom: 1px solid rgba(255,255,255,0.1);
        width: 100%;
        text-align: center;
        color: white;
        text-decoration: none;
    }
    
    .nav-links a:last-child {
        border-bottom: none;
    }
}

.nav-links a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    transition: all 0.3s ease;
    font-weight: 500;
}

.nav-links a:hover {
    background: rgba(255,255,255,0.2);
    transform: translateY(-2px);
}

.login-btn {
    background: #ff6b6b;
    color: white;
    padding: 0.7rem 1.5rem;
    border-radius: 25px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(255,107,107,0.3);
    pointer-events: auto !important;
    z-index: 2000; /* ensure above overlapping elements */
}

/* Visual highlight for debugging clickable area */
.login-btn.highlight {
    box-shadow: 0 0 0 4px rgba(255, 107, 107, 0.12), 0 0 25px rgba(255, 107, 107, 0.2);
    animation: pulse 1.2s infinite;
}

@keyframes pulse {
    0% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-2px) scale(1.02); }
    100% { transform: translateY(0) scale(1); }
}

/* Overlay rectangle to show exact clickable region */
.clickable-highlight-overlay {
    position: absolute;
    border: 2px dashed rgba(255,107,107,0.7);
    background: rgba(255,107,107,0.05);
    z-index: 2001;
    pointer-events: none; /* allow clicks to pass through */
    transition: opacity 0.4s ease;
    border-radius: 8px;
}

.login-btn:hover {
    background: #ff5252;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255,107,107,0.4);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
    padding: 4rem 2rem;
    margin-bottom: 3rem;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Categories Section */
.categories {
    padding: 3rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.categories h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #333;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    text-align: center;
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.category-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #333;
}

.category-card p {
    color: #666;
    margin-bottom: 1.5rem;
}

/* Features Section */
.features {
    background: #f8f9fa;
    padding: 4rem 2rem;
}

.features-container {
    max-width: 1200px;
    margin: 0 auto;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #333;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-item {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
    text-align: center;
    transition: all 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.15);
}

.feature-item h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #333;
}

.feature-item p {
    color: #666;
}

/* About Section Styles */
.about-section {
    padding: 4rem 0;
    background: white;
}

.about-section .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.8;
}

.about-text ul {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.about-text li {
    margin: 0.5rem 0;
    color: #555;
}

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin: 2rem 0;
    padding: 1rem;
}

.stat-item {
    text-align: center;
    padding: 2rem 1.5rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: black;
    border-radius: 15px;
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    min-height: 120px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px rgba(102, 126, 234, 0.4);
}

.stat-item h3 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    font-weight: bold;
    line-height: 1;
    text-shadow: 0 2px 4px rgba(255,255,255,0.3);
}

.stat-item p {
    font-size: 1.1rem;
    opacity: 0.95;
    font-weight: 500;
    margin: 0;
}

/* Contact Section Styles */
.contact-section {
    padding: 4rem 0;
    background: #f8f9fa;
}

.contact-section .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.contact-info h3,
.contact-form h3 {
    color: #333;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.contact-details {
    margin-top: 1.5rem;
}

.contact-item {
    margin: 1rem 0;
    padding: 1rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.contact-item strong {
    color: #667eea;
    display: block;
    margin-bottom: 0.5rem;
}

.contact-item a {
    color: #333;
    text-decoration: none;
    transition: color 0.3s ease;
}

.contact-item a:hover {
    color: #667eea;
}

.contact-form {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.contact-form .form-group {
    margin-bottom: 1.5rem;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: #667eea;
}

.contact-form textarea {
    resize: vertical;
    min-height: 120px;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Responsive Design for New Sections */
@media (max-width: 768px) {
    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .about-stats {
        flex-direction: row;
        justify-content: space-around;
        gap: 1rem;
    }
    
    .stat-item {
        flex: 1;
        margin: 0 0.5rem;
        min-height: 100px;
        padding: 1.5rem 1rem;
    }
    
    .stat-item h3 {
        font-size: 2.5rem;
    }
    
    .contact-form {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .about-stats {
        flex-direction: column;
    }
    
    .stat-item {
        margin: 0.5rem 0;
    }
}

/* Footer */
footer {
    background: #333;
    color: white;
    padding: 3rem 2rem 2rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
    color: #ff6b6b;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #ff6b6b;
}

/* Login/Register Styles */
.login-container, .register-container {
    background: white;
    padding: 3rem;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 450px;
    margin: 2rem auto;
}

.login-container h2, .register-header h1 {
    text-align: center;
    color: #333;
    margin-bottom: 2rem;
    font-size: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: #555;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e9ecef;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102,126,234,0.1);
}

.login-button, .register-button {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.login-button:hover, .register-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102,126,234,0.3);
}

.error-message {
    background: #f8d7da;
    color: #721c24;
    padding: 1rem;
    border-radius: 10px;
    margin-bottom: 1rem;
    border-left: 4px solid #dc3545;
}

.success-message {
    background: #d4edda;
    color: #155724;
    padding: 1rem;
    border-radius: 10px;
    margin-bottom: 1rem;
    border-left: 4px solid #28a745;
}

/* Dashboard Styles */
.dashboard-container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

.welcome-section {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    margin-bottom: 2rem;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.welcome-section h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.test-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    height: 100%;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.category-card h3 {
    color: #333;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.category-card p {
    color: #666;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.category-action {
    margin-top: auto;
}

.start-exam-btn {
    display: inline-block;
    padding: 10px 20px;
    background: #f8f9fa;
    color: #667eea;
    border: 2px solid #667eea;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.category-card:hover .start-exam-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    transform: scale(1.05);
}

.start-test-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 1.5rem;
    border: none;
    border-radius: 10px;
    text-decoration: none;
    text-align: center;
    font-weight: bold;
    transition: all 0.3s ease;
    margin-top: auto;
}

.start-test-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102,126,234,0.3);
}

/* Exam Styles */
.exam-container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 2rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.question-panel {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
}

.question-nav {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(50px, 1fr));
    gap: 1rem;
    margin: 2rem 0;
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: 15px;
}

.question-btn {
    width: 50px;
    height: 50px;
    border: 2px solid #e9ecef;
    background: white;
    border-radius: 10px;
    cursor: pointer;
    font-weight: bold;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.question-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.question-btn.answered {
    background: #28a745;
    color: white;
    border-color: #28a745;
}

.question-btn.marked {
    background: #ffc107;
    color: #000;
    border-color: #ffc107;
}

.question-btn.current {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102,126,234,0.2);
}

.timer {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 1rem 1.5rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    font-size: 1.3rem;
    font-weight: bold;
    color: #dc3545;
    z-index: 1000;
}

.controls {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: 15px;
    justify-content: space-between;
    flex-wrap: wrap;
}

.controls button {
    padding: 1rem 2rem;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-weight: bold;
    font-size: 1rem;
    transition: all 0.3s ease;
}

button[onclick="markForReview()"] {
    background: #ffc107;
    color: #000;
}

button[onclick="previousQuestion()"],
button[onclick="nextQuestion()"] {
    background: #6c757d;
    color: white;
}

button[onclick="submitExam()"] {
    background: #28a745;
    color: white;
}

.controls button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

#questionContainer {
    padding: 2rem;
    background: #fff;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
}

.options label {
    display: block;
    padding: 1.5rem;
    margin: 1rem 0;
    background: #f8f9fa;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.options label:hover {
    background: #e9ecef;
    border-color: #667eea;
}

.options input[type="radio"] {
    margin-right: 1rem;
    transform: scale(1.2);
}

/* Result Styles */
.result-container {
    max-width: 1000px;
    margin: 2rem auto;
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.score-card {
    text-align: center;
    padding: 2rem;
    margin-bottom: 2rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 15px;
}

.score {
    font-size: 4rem;
    font-weight: bold;
    margin: 1rem 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: 10px;
    text-align: center;
    border-left: 4px solid #667eea;
}

.chart-container {
    margin: 2rem 0;
    height: 400px;
}

/* My Tests Styles */
.test-card {
    background: white;
    padding: 2rem;
    margin-bottom: 1.5rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.3s ease;
}

.test-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
}

.test-info {
    flex: 1;
    min-width: 250px;
}

.test-info h3 {
    margin: 0 0 1rem 0;
    color: #333;
    font-size: 1.3rem;
}

.test-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin: 1rem 0;
}

/* Removed conflicting stat-item definition - using the main one above */

.view-result-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 2rem;
    border-radius: 10px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
    margin-left: 2rem;
}

.view-result-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102,126,234,0.3);
}

/* ===== RESPONSIVE DESIGN BREAKPOINTS ===== */

/* Mobile First - Base styles for mobile (320px+) */
@media (max-width: 767px) {
    .logo {
        font-size: 1.4rem;
    }
    
    .nav-links a {
        width: 100%;
        text-align: center;
        padding: 0.75rem 1rem;
    }
    
    .hero h1 {
        font-size: 2rem;
        line-height: 1.2;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
        margin: 0.5rem 0;
    }
    
    .container {
        padding: 0 15px;
    }
    
    .card {
        padding: 1rem;
        margin-bottom: 1rem;
    }
    
    .grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .admin-nav-links {
        display: none;
        flex-direction: column;
        gap: 1rem;
        width: 100%;
        background: rgba(255,255,255,0.1);
        padding: 1rem;
        margin-top: 1rem;
        border-radius: 8px;
    }
    
    .admin-nav-links.active {
        display: flex;
    }
    
    .admin-nav-links a {
        width: 100%;
        text-align: center;
        font-size: 0.9rem;
    }
    
    .admin-stats-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .admin-action-buttons {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .admin-btn {
        width: 100%;
        max-width: 300px;
    }
    
    .table-responsive {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
    }
    
    table {
        min-width: 600px;
    }
}

/* Tablet Styles (768px+) */
@media (min-width: 768px) {
    .mobile-menu-toggle {
        display: none;
    }
    
    .nav-links {
        display: flex;
        flex-direction: row;
        gap: 2rem;
        background: none;
        padding: 0;
        margin: 0;
        width: auto;
    }
    
    .nav-links a {
        width: auto;
        text-align: left;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero p {
        font-size: 1.2rem;
    }
    
    .btn {
        width: auto;
        max-width: none;
    }
    
    .grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .admin-nav-links {
        display: flex;
        flex-direction: row;
        gap: 1rem;
        background: none;
        padding: 0;
        margin: 0;
        width: auto;
    }
    
    .admin-nav-links a {
        width: auto;
        text-align: left;
        font-size: 0.9rem;
    }
    
    .admin-stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .admin-action-buttons {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .admin-btn {
        width: auto;
        max-width: none;
    }
}

/* Desktop Styles (1024px+) */
@media (min-width: 1024px) {
    .hero h1 {
        font-size: 3rem;
    }
    
    .hero p {
        font-size: 1.3rem;
    }
    
    .grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }
    
    .admin-stats-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 2rem;
    }
    
    .admin-action-buttons {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }
}

/* Large Desktop (1200px+) */
@media (min-width: 1200px) {
    .admin-action-buttons {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* Utility Classes for Responsive Design */
.hide-mobile { display: none; }
.show-mobile { display: block; }

@media (min-width: 768px) {
    .hide-mobile { display: block; }
    .show-mobile { display: none; }
}

/* Print Styles */
@media print {
    .navbar,
    .admin-nav,
    .btn,
    .admin-btn,
    .mobile-menu-toggle {
        display: none !important;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.4;
    }
    
    .container,
    .admin-container {
        max-width: none;
        margin: 0;
        padding: 0;
    }
}

.no-tests {
    text-align: center;
    padding: 4rem;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Responsive Design */
@media screen and (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .nav-links {
        gap: 1rem;
    }
    
    .category-grid {
        grid-template-columns: 1fr;
    }
    
    .test-card {
        flex-direction: column;
        align-items: stretch;
    }
    
    .view-result-btn {
        margin: 1rem 0 0 0;
        text-align: center;
        display: block;
    }
    
    .controls {
        flex-direction: column;
    }
    
    .question-nav {
        grid-template-columns: repeat(auto-fill, minmax(40px, 1fr));
    }
    
    .question-btn {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
}

@media screen and (max-width: 480px) {
    .login-container, .register-container {
        padding: 2rem 1rem;
        margin: 1rem;
    }
    
    .hero {
        padding: 2rem 1rem;
    }
    
    .categories, .features {
        padding: 2rem 1rem;
    }
    
    .dashboard-container {
        padding: 0 1rem;
    }
}