body {
    margin: 0;
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    color: #222;
    transition: background 0.3s, color 0.3s;
}

body.dark {
    background-color: #1a1a1a;
    color: #eee;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 20px;
}

.header {
    background-color: #fff;
    border-bottom: 1px solid #ddd;
    padding: 15px 0;
}

body.dark .header {
    background-color: #222;
    border-color: #444;
}

.logo {
    font-size: 1.5em;
    font-weight: bold;
}

.nav {
    display: flex;
    gap: 15px;
    align-items: center;
    float: right;
}

.nav a {
    text-decoration: none;
    color: #0077cc;
}

body.dark .nav a {
    color: #66bfff;
}

#themeToggle {
    background: none;
    border: 1px solid #ccc;
    border-radius: 4px;
    padding: 4px 8px;
    cursor: pointer;
    font-size: 1em;
    color: inherit;
    background-color: #f0f0f0;
}

body.dark #themeToggle {
    background-color: #333;
    border-color: #555;
}

.intro {
    text-align: center;
    margin: 40px 0;
}

h2 {
    font-size: 1.8em;
    margin-bottom: 10px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 15px;
    padding: 0;
    list-style: none;
    margin: 20px 0;
}

.subscribe {
    text-align: center;
    margin: 50px 0;
}

.button {
    display: inline-block;
    background-color: #0077cc;
    color: white;
    padding: 10px 20px;
    border-radius: 4px;
    text-decoration: none;
    transition: background 0.3s;
}

.button:hover {
    background-color: #005fa3;
}

.footer {
    text-align: center;
    font-size: 0.9em;
    padding: 20px 0;
    border-top: 1px solid #ddd;
}

body.dark .footer {
    border-color: #444;
}

/* ===== Навигация между уроками (prev / next) ===== */
.lesson-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid #ddd;
}

.lesson-nav a {
    padding: 10px 20px;
    text-decoration: none;
    background-color: #007acc;
    color: white;
    border-radius: 6px;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.lesson-nav a:hover {
    background-color: #005fa3;
}

/* ===== Главная страница: список уроков ===== */
.lesson-list {
    display: grid;
    gap: 16px;
    margin-top: 24px;
}

.lesson-list a {
    display: block;
    padding: 16px;
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    border-radius: 8px;
    text-decoration: none;
    color: #222;
    transition: background-color 0.2s ease;
}

.lesson-list a:hover {
    background-color: #eef6fb;
    border-color: #007acc;
}

/* ===== Тёмная тема ===== */
body.dark .lesson-nav a {
    background-color: #3399ff;
    color: #fff;
}

body.dark .lesson-nav a:hover {
    background-color: #2277cc;
}

body.dark .lesson-list a {
    background-color: #1e1e1e;
    border-color: #333;
    color: #eee;
}

body.dark .lesson-list a:hover {
    background-color: #2a2a2a;
    border-color: #3399ff;
}

.code-block {
    position: relative;
    background-color: #f4f4f4;
    border: 1px solid #ccc;
    border-radius: 6px;
    overflow: auto;
    padding: 12px;
    margin: 20px 0;
}

.code-block pre {
    margin: 0;
    background: transparent;
    white-space: pre-wrap;
    word-wrap: break-word;
    font-family: monospace;
}

.copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    background: #007acc;
    color: white;
    border: none;
    padding: 6px 10px;
    border-radius: 4px;
    font-size: 12px;
    cursor: pointer;
    opacity: 0.8;
    transition: opacity 0.2s ease;
}

.copy-btn:hover {
    opacity: 1;
}

/* Тёмная тема */
body.dark .code-block {
    background-color: #1e1e1e;
    border-color: #333;
}

body.dark .copy-btn {
    background-color: #3399ff;
}

/* ===== Контейнер карточек ===== */
.card-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 16px;
    margin-top: 24px;
}

/* ===== Стиль карточек ===== */
.card a {
    display: block;
    padding: 16px;
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    border-radius: 8px;
    text-decoration: none;
    color: #222;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

.card a:hover {
    background-color: #eef6fb;
    border-color: #007acc;
}

/* ===== Тёмная тема для карточек ===== */
body.dark .card a {
    background-color: #1e1e1e;
    border-color: #333;
    color: #eee;
}

body.dark .card a:hover {
    background-color: #2a2a2a;
    border-color: #3399ff;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.3s ease, color 0.3s ease;
}

.btn-primary {
    background-color: #007bff;
    color: #fff;
}

.btn-primary:hover {
    background-color: #0056b3;
}

/* Темная тема */
body.dark .btn-primary {
    background-color: #3390ff;
    color: #fff;
}

body.dark .btn-primary:hover {
    background-color: #1e6bb8;
}

.form-group {
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
}

label {
    margin-bottom: 5px;
    font-weight: 500;
}

.input {
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s, background-color 0.3s, color 0.3s;
}

.input:focus {
    border-color: #007bff;
    outline: none;
    background-color: #fff;
    color: #000;
}

/* Тёмная тема */
body.dark .input {
    background-color: #1e1e1e;
    border: 1px solid #555;
    color: #eee;
}

body.dark .input:focus {
    border-color: #3390ff;
    background-color: #2a2a2a;
    color: #fff;
}

.input,
.textarea {
    width: 100%;
    padding: 0.6rem;
    font-size: 1rem;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-family: monospace;
    background-color: #fff;
    color: #000;
    resize: vertical;
    box-sizing: border-box;
}

body.dark .input,
body.dark .textarea {
    background-color: #1e1e1e;
    color: #eaeaea;
    border-color: #555;
}

body.dark .label {
    color: #ccc;
}



.filters {
    margin-bottom: 1.5rem;
}

.filters button {
    background: #e0e0e0;
    border: none;
    padding: 0.5rem 1rem;
    margin-right: 0.5rem;
    border-radius: 9999px;
    cursor: pointer;
    transition: 0.2s;
}

.filters button.active,
.filters button:hover {
    background: #0070f3;
    color: white;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
}

.card {
    background: white;
    padding: 1rem;
    border-radius: 1rem;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
    transition: transform 0.2s;
}

.card:hover {
    transform: translateY(-4px);
}

.category {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: #888;
    margin-bottom: 0.5rem;
}

.title {
    font-size: 1rem;
    font-weight: 600;
    color: #222;
    text-decoration: none;
}