/* Общие стили */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #637bfe;
    --primary-dark: #4c63d2;
    --secondary-color: #ff6b95;
    --accent-color: #75e6da;
    --text-color: #333;
    --text-light: #777;
    --bg-light: #f9f9ff;
    --white: #fff;
    --border-color: #eaeaea;
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Open Sans', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: var(--bg-light);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.section-subtitle {
    font-size: 1.1rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-light);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 12px 30px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-block;
    text-decoration: none;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(99, 123, 254, 0.2);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    padding: 12px 30px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-block;
    text-decoration: none;
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(99, 123, 254, 0.2);
}

.btn-test {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    width: 100%;
    margin-top: 15px;
}

.btn-test:hover {
    background-color: var(--primary-dark);
}

/* Header */
.header {
    background-color: var(--white);
    box-shadow: var(--shadow);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 15px 0;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--text-color);
    font-weight: 700;
    font-size: 1.5rem;
}

.logo i {
    color: var(--primary-color);
    margin-right: 10px;
    font-size: 1.8rem;
}

.nav ul {
    display: flex;
    list-style: none;
}

.nav ul li {
    margin: 0 15px;
}

.nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav ul li a:hover,
.nav ul li a.active {
    color: var(--primary-color);
}

.nav ul li a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
}

.auth-buttons {
    display: flex;
    gap: 15px;
}

.btn-login, .btn-register {
    padding: 8px 20px;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn-login {
    background-color: transparent;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
}

.btn-register {
    background-color: var(--primary-color);
    border: 1px solid var(--primary-color);
    color: var(--white);
}

.btn-login:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-register:hover {
    background-color: var(--primary-dark);
}

.mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Sidebar */
.sidebar {
    position: fixed;
    top: 0;
    left: -300px;
    width: 300px;
    height: 100%;
    background-color: var(--white);
    box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
    z-index: 1001;
    transition: var(--transition);
    overflow-y: auto;
}

.sidebar.active {
    left: 0;
}

.sidebar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-close {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-light);
}

.sidebar-menu {
    list-style: none;
    padding: 20px 0;
}

.sidebar-menu li a {
    display: flex;
    align-items: center;
    padding: 12px 20px;
    text-decoration: none;
    color: var(--text-color);
    transition: var(--transition);
}

.sidebar-menu li a:hover {
    background-color: var(--bg-light);
    color: var(--primary-color);
}

.sidebar-menu li a i {
    margin-right: 10px;
    width: 20px;
    text-align: center;
}

.sidebar-footer {
    padding: 20px;
    border-top: 1px solid var(--border-color);
}

.user-profile {
    display: flex;
    align-items: center;
}

.user-avatar {
    margin-right: 15px;
    font-size: 2.5rem;
    color: var(--primary-color);
}

.user-info p {
    font-weight: 600;
    margin-bottom: 5px;
}

.login-link {
    font-size: 0.9rem;
    color: var(--primary-color);
    text-decoration: none;
}

/* Hero Section */
.hero {
    padding: 150px 0 100px;
    background: linear-gradient(135deg, #f5f7ff 0%, #e6e9ff 100%);
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.hero-content {
    flex: 1;
    max-width: 600px;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    color: var(--text-color);
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: var(--text-light);
}

.hero-stats {
    display: flex;
    margin-bottom: 2rem;
}

.stat {
    margin-right: 30px;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-text {
    font-size: 0.9rem;
    color: var(--text-light);
}

.hero-image {
    flex: 1;
    text-align: center;
}

.hero-image img {
    max-width: 100%;
    height: auto;
}

/* Problems Section */
.problems {
    padding: 100px 0;
    background-color: var(--white);
}

.problems-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.problem-card {
    background-color: var(--white);
    border-radius: 10px;
    padding: 30px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 4px solid var(--primary-color);
}

.problem-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.problem-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.problem-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
}

.problem-card p {
    color: var(--text-light);
    margin-bottom: 20px;
}

.problem-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.problem-link i {
    margin-left: 5px;
    transition: var(--transition);
}

.problem-link:hover i {
    transform: translateX(5px);
}

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

/* Tests Section */
.tests {
    padding: 100px 0;
    background-color: var(--bg-light);
}

.tests-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 40px;
}

.filter-btn {
    background-color: var(--white);
    border: 1px solid var(--border-color);
    padding: 8px 20px;
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.filter-btn.active,
.filter-btn:hover {
    background-color: var(--primary-color);
    color: var(--white);
    border-color: var(--primary-color);
}

.tests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.test-card {
    background-color: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
}

.test-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.test-badge {
    position: absolute;
    top: 15px;
    right: 15px;
    background-color: var(--primary-color);
    color: var(--white);
    padding: 5px 10px;
    border-radius: 5px;
    font-size: 0.8rem;
    font-weight: 600;
}

.test-image {
    height: 180px;
    overflow: hidden;
}

.test-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.test-card:hover .test-image img {
    transform: scale(1.1);
}

.test-content {
    padding: 20px;
}

.test-content h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.test-content p {
    color: var(--text-light);
    margin-bottom: 15px;
    font-size: 0.95rem;
}

.test-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 15px;
}

.test-meta span {
    display: flex;
    align-items: center;
}

.test-meta i {
    margin-right: 5px;
}

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

/* Features Section */
.features {
    padding: 100px 0;
    background-color: var(--white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 30px;
}

.feature-card {
    text-align: center;
    padding: 30px 20px;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-10px);
}

.feature-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
}

.feature-card p {
    color: var(--text-light);
}

/* About Section */
.about {
    padding: 100px 0;
    background-color: var(--bg-light);
}

.about .container {
    display: flex;
    align-items: center;
    gap: 50px;
}

.about-content {
    flex: 1;
}

.about-content p {
    margin-bottom: 20px;
    color: var(--text-light);
}

.about-stats {
    display: flex;
    margin-top: 30px;
    gap: 30px;
}

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

.about-stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.about-stat-text {
    font-size: 0.9rem;
    color: var(--text-light);
}

.about-image {
    flex: 1;
    text-align: center;
}

.about-image img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

/* Contact Section */
.contact {
    padding: 100px 0;
    background-color: var(--white);
}

.contact-content {
    display: flex;
    gap: 50px;
}

.contact-info {
    flex: 1;
}

.contact-item {
    display: flex;
    margin-bottom: 30px;
}

.contact-icon {
    width: 60px;
    height: 60px;
    background-color: var(--bg-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 20px;
    font-size: 1.5rem;
    color: var(--primary-color);
}

.contact-text h3 {
    margin-bottom: 5px;
}

.contact-text p {
    color: var(--text-light);
}

.contact-form {
    flex: 1;
}

.form-group {
    margin-bottom: 20px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-family: 'Open Sans', sans-serif;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(99, 123, 254, 0.2);
}

/* Footer */
.footer {
    background-color: #2a2a2a;
    color: var(--white);
    padding: 70px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 50px;
}

.footer-section h3 {
    color: var(--white);
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-section p {
    color: #aaa;
    margin-bottom: 20px;
}

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

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section ul li a {
    color: #aaa;
    text-decoration: none;
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: var(--primary-color);
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: #3a3a3a;
    border-radius: 50%;
    color: var(--white);
    transition: var(--transition);
}

.social-links a:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.subscribe-form {
    display: flex;
    margin-top: 15px;
}

.subscribe-form input {
    flex: 1;
    padding: 10px 15px;
    border: none;
    border-radius: 5px 0 0 5px;
    font-family: 'Open Sans', sans-serif;
}

.subscribe-form button {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 0 15px;
    border-radius: 0 5px 5px 0;
    cursor: pointer;
    transition: var(--transition);
}

.subscribe-form button:hover {
    background-color: var(--primary-dark);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #3a3a3a;
    color: #aaa;
    font-size: 0.9rem;
}

/* Адаптивность */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-content {
        margin-bottom: 50px;
    }
    
    .about .container {
        flex-direction: column;
    }
    
    .contact-content {
        flex-direction: column;
    }
}

@media (max-width: 768px) {
    .nav, .auth-buttons {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .problems-grid,
    .tests-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 576px) {
    .hero {
        padding: 120px 0 80px;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .stat {
        margin-right: 0;
    }
    
    .tests-filter {
        flex-direction: column;
        align-items: center;
    }
    
    .about-stats {
        flex-direction: column;
        gap: 20px;
    }
}