/* --- Глобальные стили и переменные --- */
:root {
    --primary-color: #007bff; /* Яркий синий для акцентов */
    --primary-hover: #0056b3;
    --dark-bg: #1a1c20;      /* Темный фон */
    --medium-bg: #25282e;   /* Фон для карточек */
    --light-bg: #32363e;    /* Фон при наведении */
    --text-primary: #f0f0f0; /* Основной светлый текст */
    --text-secondary: #a0a0a0;/* Второстепенный текст */
    --border-color: #40444c; /* Цвет границ */
    --font-family: 'Inter', sans-serif;
    --container-width: 1200px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background-color: var(--dark-bg);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 16px;
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

h1, h2, h3, h4 {
    line-height: 1.3;
    margin-bottom: 20px;
    font-weight: 600;
}

h1 { font-size: 2.8rem; }
h2 { font-size: 2.2rem; text-align: center; margin-bottom: 50px; }
h3 { font-size: 1.8rem; }
h4 { font-size: 1.2rem; }

section {
    padding: 80px 0;
}

section:nth-of-type(odd) {
    background-color: var(--medium-bg);
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--primary-hover);
}

ul {
    list-style: none;
}

/* --- Шапка --- */
.site-header {
    background-color: rgba(26, 28, 32, 0.85);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.main-nav ul {
    display: flex;
    gap: 30px;
}

.main-nav a {
    color: var(--text-secondary);
    font-weight: 500;
    position: relative;
    padding-bottom: 5px;
}

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

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.main-nav a:hover::after {
    width: 100%;
}

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

.header-address {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.header-email-btn {
    background-color: var(--primary-color);
    color: #fff;
    padding: 8px 15px;
    border-radius: 5px;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.header-email-btn:hover {
    background-color: var(--primary-hover);
    color: #fff;
}

.burger-menu {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.8rem;
    cursor: pointer;
}

/* --- Первый блок (Hero) --- */
.hero-section {
    padding-top: 120px;
    padding-bottom: 120px;
}

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

.hero-content {
    flex: 1;
}

.hero-content p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.hero-advantages {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.hero-advantages li {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
}

.hero-advantages i {
    color: var(--primary-color);
    font-size: 1.2rem;
    width: 25px;
    text-align: center;
}

.hero-image {
    flex: 0 0 45%;
}
.hero-image img {
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

/* --- Характеристики (Табы) --- */
.tabs-container {
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--dark-bg);
    padding: 20px;
    border-radius: 8px;
}

.tab-buttons {
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    padding: 15px 30px;
    cursor: pointer;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
}

.tab-btn.active {
    color: var(--text-primary);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.5s ease;
}

.tab-content ul {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.tab-content li {
    background-color: var(--medium-bg);
    padding: 15px;
    border-radius: 5px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.tab-content i {
    font-size: 1.5rem;
    color: var(--primary-color);
    width: 30px;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- Описание --- */
.description-container {
    display: flex;
    align-items: center;
    gap: 50px;
}

.description-text { flex: 1; }
.description-text p { color: var(--text-secondary); margin-bottom: 15px; }
.description-image { flex: 0 0 40%; }

/* --- 6 Преимуществ --- */
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.advantage-item {
    background-color: var(--dark-bg);
    padding: 30px;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.advantage-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 123, 255, 0.1);
}

.advantage-item i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.advantage-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* --- Комплектация и Установка --- */
.kit-container {
    display: flex;
    gap: 40px;
}

.kit-column {
    flex: 1;
    background-color: var(--dark-bg);
    padding: 30px;
    border-radius: 8px;
}

.kit-column h3 {
    border-bottom: 2px solid var(--primary-color);
    display: inline-block;
    padding-bottom: 10px;
}

.kit-column ul {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-top: 20px;
}

.kit-column li {
    display: flex;
    align-items: center;
    gap: 15px;
}

.kit-column i {
    color: var(--primary-color);
}

/* --- Сферы применения --- */
.applications-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.application-item {
    position: relative;
    border-radius: 8px;
    overflow: hidden;
    color: #fff;
}

.application-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.application-item:hover img {
    transform: scale(1.05);
}

.application-item::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to top, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0) 60%);
}

.application-item h4,
.application-item p {
    position: absolute;
    left: 20px;
    z-index: 2;
    padding-right: 20px;
}

.application-item h4 {
    bottom: 50px;
    font-size: 1.4rem;
}

.application-item p {
    bottom: 20px;
    font-size: 0.9rem;
    opacity: 0.8;
}

/* --- Требования к установке --- */
.requirements-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    max-width: 1000px;
    margin: 0 auto;
}

.requirements-list li {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    padding: 20px;
    background-color: var(--medium-bg);
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

.requirements-list i {
    font-size: 1.5rem;
    margin-top: 5px;
    color: var(--primary-color);
}

/* --- Блок цен --- */
.pricing-section { background-color: #22272E; }
.price-block {
    max-width: 900px;
    margin: 0 auto;
    background-color: #2D333B;
    border-radius: 16px;
    padding: 35px;
    width: 100%;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4);
    border: 1px solid #434a55;
    overflow: hidden;
}
.price-block h2 { color: #CDD9E5; margin-bottom: 10px; }
.price-block .subtitle { text-align: center; font-size: 15px; color: #768390; margin-bottom: 35px; }
.chart-container { position: relative; height: 350px; width: 100%; margin-bottom: 40px; }
.price-table { width: 100%; border-collapse: collapse; }
.price-table th, .price-table td { padding: 18px 12px; text-align: left; border-bottom: 1px solid #434a55; }
.price-table thead th { font-size: 13px; font-weight: 600; color: #768390; text-transform: uppercase; }
.store-name { font-weight: 600; font-size: 16px; display: flex; align-items: center; }
.store-name i { margin-right: 12px; font-size: 18px; width: 20px; text-align: center;}
.price { font-weight: 700; font-size: 18px; color: #CDD9E5; }
.delivery-info { font-size: 14px; color: #768390; }
.buy-button { display: inline-block; background-color: #434a55; color: #CDD9E5; padding: 10px 20px; border-radius: 8px; font-weight: 600; text-align: center; transition: all 0.2s ease; border: none; }
.buy-button:hover { background-color: #505864; color: #fff; }
.price-table tr.highlight { background-color: rgba(64, 128, 255, 0.1); border-left: 4px solid #4080FF; }
.price-table tr.highlight .store-name i { color: #4080FF; }
.price-table tr.highlight .buy-button { background-color: #4080FF; color: #fff; }

/* --- Галерея --- */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
}

.gallery-grid img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    transition: transform 0.3s ease, filter 0.3s ease;
    cursor: pointer;
}

.gallery-grid img:hover {
    transform: scale(1.03);
    filter: brightness(1.1);
}

/* --- FAQ --- */
.faq-grid {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.faq-item {
    background-color: var(--dark-bg);
    padding: 20px;
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

.faq-item p {
    color: var(--text-secondary);
}

/* --- Отзывы --- */
.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 20px;
}
.review-item {
    background-color: var(--dark-bg);
    padding: 25px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
}
.review-item blockquote {
    flex-grow: 1;
    font-style: italic;
    color: var(--text-secondary);
    border-left: 3px solid var(--primary-color);
    padding-left: 15px;
    margin-bottom: 15px;
}
.review-item cite {
    font-weight: 600;
    color: var(--text-primary);
    text-align: right;
}

/* --- Контакты --- */
.contact-section {
    text-align: center;
}

.contact-details {
    display: flex;
    justify-content: center;
    gap: 50px;
    margin: 40px 0;
    text-align: left;
}
.contact-info-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
}
.contact-info-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-top: 5px;
}
.contact-info-item span {
    font-weight: 600;
    color: var(--text-secondary);
}
.contact-info-item a, .contact-info-item p {
    font-size: 1.1rem;
}

.cta-button {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 15px 40px;
    font-size: 1.2rem;
    font-weight: 600;
    border-radius: 8px;
    transition: all 0.3s ease;
}
.cta-button:hover {
    background-color: var(--primary-hover);
    transform: scale(1.05);
    color: #fff;
}

/* --- Футер --- */
.site-footer {
    background-color: var(--dark-bg);
    text-align: center;
    padding: 30px 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}
.footer-container p { margin-bottom: 10px; }
.copyright { font-weight: 600; color: var(--text-primary); }
.privacy-notice { font-size: 0.8rem; }

/* --- Адаптивность --- */
@media (max-width: 1024px) {
    h1 { font-size: 2.4rem; }
    h2 { font-size: 2rem; }
    .main-nav { display: none; }
    .header-contacts { display: none; }
    .burger-menu { display: block; }
    .main-nav.active {
        display: flex;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--medium-bg);
        flex-direction: column;
        padding: 20px;
    }
    .main-nav.active ul { flex-direction: column; align-items: center; }
    .hero-container, .description-container { flex-direction: column; text-align: center; }
    .hero-image { order: -1; }
    .applications-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    section { padding: 60px 0; }
    h1 { font-size: 2rem; }
    h2 { font-size: 1.8rem; margin-bottom: 30px; }

    .kit-container, .contact-details { flex-direction: column; }
    .gallery-grid { grid-template-columns: repeat(2, 1fr); }
    .advantages-grid { grid-template-columns: 1fr; }
    .price-table { font-size: 0.9rem; }
    .price-table th, .price-table td { padding: 10px 5px; }
}

@media (max-width: 480px) {
    .tab-btn { padding: 10px 15px; font-size: 0.9rem; }
    .gallery-grid { grid-template-columns: 1fr; }
    .reviews-grid { grid-template-columns: 1fr; }
    .price-block { padding: 20px; }
    .chart-container { height: 300px; }
}