/* --- Общие стили --- */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    background-color: #f0f2f5;
    color: #333;
}

a {
    text-decoration: none;
    color: inherit;
}

/* --- Header и навигация --- */
header {
    background-color: #0077b6;
    color: white;
    padding: 15px 0;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

header h1 {
    margin: 0;
    font-size: 2em;
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 10px 0 0 0;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
}

nav ul li {
    margin: 0 15px;
}

nav ul li a {
    color: white;
    font-weight: bold;
    padding: 5px 10px;
    transition: background 0.3s, color 0.3s;
}

nav ul li a:hover {
    background-color: #00b4d8;
    border-radius: 5px;
}

/* --- Main content --- */
main {
    padding: 30px 20px;
    max-width: 1000px;
    margin: auto;
}

section {
    margin-bottom: 30px;
    background-color: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
}

h2 {
    color: #0077b6;
}

h3 {
    color: #023e8a;
}

/* --- Списки --- */
ul {
    padding-left: 20px;
}

/* --- Footer --- */
footer {
    background-color: #023e8a;
    color: white;
    text-align: center;
    padding: 15px 0;
    margin-top: 20px;
}

/* --- Блоки кода --- */
pre {
    background-color: #1e1e2f;
    color: #f8f8f2;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    margin-bottom: 20px;
}

code {
    font-family: 'Courier New', Courier, monospace;
}

/* --- Адаптивность --- */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    nav ul li {
        margin: 5px 0;
    }
}