:root {
    --primary-color: #005baa; /* Синий, ассоциирующийся с РЖД */
    --secondary-color: #d52b1e; /* Красный акцент */
    --accent-color: #ffcc00; /* Желтый для выделения */
    --light-color: #f5f5f5;
    --dark-color: #333;
    --gray-color: #666;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --border-radius: 8px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    line-height: 1.6;
    color: var(--dark-color);
    background-color: #f9f9f9;
    padding-bottom: 2rem;
}

/* Шапка */
header {
    background: linear-gradient(to right, var(--primary-color), #003d7a);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo i {
    font-size: 2.2rem;
    color: var(--accent-color);
}

.logo h1 {
    font-size: 1.5rem;
    line-height: 1.2;
}

.logo span {
    font-size: 0.85rem;
    opacity: 0.9;
    display: block;
    margin-top: 0.2rem;
}

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

/* Навигация */
nav {
    display: block;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 5px;
    flex-wrap: wrap;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    font-weight: 600;
    padding: 8px 12px;
    border-radius: 4px;
    transition: all 0.3s;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 6px;
    background: rgba(255, 255, 255, 0.05);
}

.nav-menu a:hover {
    background-color: rgba(255, 255, 255, 0.15);
}

/* Основной контент */
main {
    padding-top: 2rem;
}

.hero {
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    border-top: 4px solid var(--primary-color);
}

.hero h2 {
    color: var(--primary-color);
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.05rem;
    color: var(--gray-color);
    margin-bottom: 1.5rem;
}

.reference-block {
    background: #f0f7ff;
    padding: 1.2rem;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--secondary-color);
    margin-top: 1.5rem;
}

.reference-block h3, .reference-block h4 {
    color: var(--primary-color);
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Секции контента */
.content-section {
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2.5rem;
    box-shadow: var(--shadow);
}

.section-title {
    color: var(--primary-color);
    margin-bottom: 0.8rem;
    font-size: 1.6rem;
    display: flex;
    align-items: center;
    gap: 12px;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--light-color);
}

.section-subtitle {
    color: var(--gray-color);
    font-size: 1rem;
    margin-bottom: 1.5rem;
    font-style: italic;
}

/* Карточки методов */
.methods-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.method-card {
    border: 1px solid #e0e0e0;
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.method-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.method-header {
    background: linear-gradient(to right, var(--primary-color), #0066cc);
    color: white;
    padding: 1.2rem;
    display: flex;
    align-items: center;
    gap: 12px;
}

.method-header i {
    font-size: 1.5rem;
}

.method-header h3 {
    font-size: 1.2rem;
    font-weight: 600;
}

.method-content {
    padding: 1.5rem;
}

.method-content p {
    margin-bottom: 0.8rem;
}

.method-content strong {
    color: var(--primary-color);
}

.method-content em {
    color: var(--gray-color);
    font-size: 0.9rem;
}

/* Системы на борту */
.onboard-systems {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.system-card {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border-top: 4px solid var(--secondary-color);
}

.system-card h3 {
    color: var(--secondary-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.system-card ul {
    list-style: none;
    margin-left: 0.5rem;
}

.system-card li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e9ecef;
    position: relative;
    padding-left: 1.5rem;
}

.system-card li:before {
    content: "•";
    color: var(--primary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Таблица стационарных средств */
.stationary-table {
    overflow-x: auto;
    margin: 2rem 0;
    border-radius: var(--border-radius);
    border: 1px solid #ddd;
}

table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}

table th {
    background: linear-gradient(to right, var(--primary-color), #0066cc);
    color: white;
    text-align: left;
    padding: 1rem;
    font-weight: 600;
}

table td {
    padding: 0.9rem;
    border-bottom: 1px solid #eee;
    vertical-align: top;
}

table tr:nth-child(even) {
    background-color: #f8f9fa;
}

table tr:hover {
    background-color: #e3f2fd;
}

/* Документация */
.docs-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.doc-category {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: var(--border-radius);
}

.doc-category h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.1rem;
}

.doc-category ul {
    list-style: none;
}

.doc-category li {
    padding: 0.7rem 0;
    border-bottom: 1px solid #e9ecef;
}

.doc-category li:last-child {
    border-bottom: none;
}

.doc-category strong {
    color: var(--secondary-color);
}

/* Подвал */
footer {
    background: linear-gradient(to right, #2c3e50, #34495e);
    color: white;
    padding: 2.5rem 0 1.5rem;
    margin-top: 3rem;
}

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

.footer-section h3 {
    color: var(--accent-color);
    margin-bottom: 1.2rem;
    font-size: 1.1rem;
}

.footer-section p {
    color: #ccc;
    font-size: 0.9rem;
    line-height: 1.5;
}

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

.footer-section li {
    margin-bottom: 0.7rem;
    color: #ddd;
    font-size: 0.9rem;
}

.footer-section a {
    color: #ddd;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: var(--accent-color);
}

.copyright {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: #aaa;
    font-size: 0.85rem;
    line-height: 1.5;
}

/* Адаптивность */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .logo h1 {
        font-size: 1.3rem;
    }

    .nav-menu {
        flex-direction: column;
        width: 100%;
        display: none;
        margin-top: 1rem;
    }

    .nav-menu.show {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
        position: absolute;
        top: 1rem;
        right: 20px;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

    .section-title {
        font-size: 1.4rem;
    }

    .methods-grid,
    .onboard-systems,
    .docs-container {
        grid-template-columns: 1fr;
    }

    .content-section {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        width: 95%;
        padding: 0 15px;
    }

    .hero, .content-section {
        padding: 1.2rem;
    }

    table {
        font-size: 0.85rem;
    }
}