/* ===== RESET & BASE ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: #fff;
}

/* ===== LAYOUT STRUCTURE ===== */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== HEADER STRUCTURE ===== */
.site-header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 0;
}

.main-navigation ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

/* ===== MAIN CONTENT STRUCTURE ===== */
.site-main {
    padding: 40px 0;
}

.posts-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

article {
    background: var(--light-color);
    border-radius: 5px;
    overflow: hidden;
}

/* ===== FOOTER STRUCTURE ===== */
.site-footer {
    background: var(--secondary-color);
    color: white;
    padding: 40px 0 20px;
}

.footer-widgets {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.site-info {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* ===== GRID STRUCTURES ===== */
.presentation-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

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

.key-numbers {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 30px 0;
    padding: 25px;
    background: #f8f9fa;
    border-radius: 10px;
}

.presentation-actions {
    display: flex;
    gap: 15px;
    margin-top: 30px;
    flex-wrap: wrap;
}

/* ===== ELEMENT STRUCTURES ===== */
.entry-header {
    padding: 20px;
}

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

.search-form {
    display: flex;
    gap: 10px;
}

/* ===== RESPONSIVE LAYOUTS ===== */
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }
    
    .main-navigation ul {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: white;
        flex-direction: column;
        padding: 20px;
        transition: var(--transition);
    }
    
    .main-navigation.active ul {
        left: 0;
    }
    
    .posts-container {
        grid-template-columns: 1fr;
    }
    
    .presentation-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .presentation-image {
        order: 2;
    }
    
    .presentation-content {
        order: 1;
        padding: 0;
    }
    
    .key-numbers {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .presentation-actions {
        flex-direction: column;
    }
    
    .products-grid,
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .product-card,
    .service-card {
        max-width: 400px;
        margin: 0 auto;
    }
}

@media (max-width: 1024px) {
    .presentation-grid {
        gap: 40px;
    }
}

/* ===== PRINT STRUCTURE ===== */
@media print {
    .site-header,
    .site-footer,
    .search-form {
        display: none;
    }
}

/* ===== UTILITY CLASSES (Structure) ===== */
.hidden { display: none; }
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }
.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }
.mt-40 { margin-top: 40px; }
.mb-40 { margin-bottom: 40px; }