/* ============================================
COMPONENT: Header Styles
Описание: Стили для шапки сайта, навигации и логотипа с эффектом фиксации при прокрутке
Версия: 1.01
============================================ */

/* === ШАПКА САЙТА === */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-fixed);
    background: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(10px);
    transition: background var(--transition-base), box-shadow var(--transition-base);
}

.site-header.scrolled {
    background: rgba(26, 26, 26, 0.98);
    box-shadow: var(--shadow-md);
}

/* === НАВИГАЦИЯ === */
.main-navigation {
    padding: var(--spacing-md) 0;
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* === ЛОГОТИП === */
.logo {
    flex-shrink: 0;
}

.logo-link {
    display: inline-block;
    transition: transform var(--transition-base);
}

.logo-link:hover {
    transform: scale(1.05);
}

.logo-text {
    font-family: var(--font-primary);
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-secondary);
    letter-spacing: 2px;
}

/* === НАВИГАЦИОННОЕ МЕНЮ === */
.nav-list {
    display: flex;
    gap: var(--spacing-xl);
    align-items: center;
}

.nav-link {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    color: var(--text-light);
    position: relative;
    padding: var(--spacing-sm) 0;
    transition: color var(--transition-base);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-secondary);
    transition: width var(--transition-base);
}

.nav-link:hover,
.nav-link:focus {
    color: var(--color-secondary);
}

.nav-link:hover::after,
.nav-link:focus::after {
    width: 100%;
}

/* === МОБИЛЬНОЕ МЕНЮ === */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    width: 30px;
    height: 30px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
}

.menu-icon {
    display: block;
    width: 100%;
    height: 3px;
    background: var(--text-light);
    transition: all var(--transition-base);
    position: relative;
}

.mobile-menu-toggle.active .menu-icon:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active .menu-icon:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .menu-icon:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* === АДАПТИВНОСТЬ === */
@media (max-width: 968px) {
    .nav-list {
        gap: var(--spacing-lg);
    }
}

@media (max-width: 768px) {
    .main-navigation {
        padding: var(--spacing-sm) 0;
    }
    
    .nav-container {
        padding: 0 var(--spacing-md);
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .logo-text {
        font-size: var(--font-size-xl);
    }
    
    .nav-list {
        position: fixed;
        top: 60px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(26, 26, 26, 0.98);
        backdrop-filter: blur(10px);
        padding: var(--spacing-xl);
        gap: var(--spacing-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
        box-shadow: var(--shadow-lg);
        max-height: calc(100vh - 60px);
        overflow-y: auto;
    }
    
    .nav-list.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-link {
        font-size: var(--font-size-lg);
        width: 100%;
        text-align: center;
        padding: var(--spacing-md) 0;
    }
}

@media (max-width: 480px) {
    .logo-text {
        font-size: var(--font-size-lg);
        letter-spacing: 1px;
    }
    
    .nav-list {
        top: 55px;
        padding: var(--spacing-lg);
        gap: var(--spacing-md);
    }
}