/* ============================================================
   layout.css — шапка, подвал, навигация, структура страниц
   ============================================================ */

/* ---- Шапка ---- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-height);
    background: rgba(15, 15, 19, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--color-border);
    transition: background var(--transition-base), border-color var(--transition-base);
}

.site-header.scrolled {
    background: rgba(15, 15, 19, 0.96);
    border-bottom-color: var(--color-border-hover);
}

.header-inner {
    display: flex;
    align-items: center;
    gap: 2rem;
    height: 100%;
}

/* ---- Логотип ---- */
.site-logo {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    text-decoration: none;
    flex-shrink: 0;
}

.logo-text {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
    white-space: nowrap;
}

.site-logo--small .logo-text {
    font-size: 1rem;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

/* ---- Навигация ---- */
.site-nav {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    margin-left: auto;
}

.nav-link {
    padding: 0.5rem 0.875rem;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    transition: color var(--transition-fast), background var(--transition-fast);
    white-space: nowrap;
}

.nav-link:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.06);
}

.nav-link--active {
    color: var(--accent-purple);
    background: rgba(102, 126, 234, 0.1);
}

/* ---- Переключатель языков ---- */
.lang-switcher {
    display: flex;
    align-items: center;
    gap: 0.125rem;
    padding: 0.25rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    flex-shrink: 0;
}

.lang-btn {
    padding: 0.3rem 0.625rem;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    color: var(--text-muted);
    border-radius: var(--radius-full);
    transition: color var(--transition-fast), background var(--transition-fast);
}

.lang-btn:hover {
    color: var(--text-primary);
}

.lang-btn.active {
    background: var(--gradient-purple);
    color: #fff;
}

/* ---- Кнопка мобильного меню ---- */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    padding: 8px;
    border-radius: var(--radius-sm);
    flex-shrink: 0;
    transition: background var(--transition-fast);
}

.nav-toggle:hover {
    background: rgba(255, 255, 255, 0.06);
}

.nav-toggle__bar {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-secondary);
    border-radius: 2px;
    transition: transform var(--transition-base), opacity var(--transition-fast);
}

/* Анимация hamburger → X */
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
    opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ---- Основное содержимое ---- */
.site-main {
    min-height: calc(100vh - var(--header-height));
}

/* ---- Заголовок внутренних страниц (features, faq, pricing) ---- */
.page-hero {
    padding-block: clamp(1.5rem, 3vw, 2.5rem) clamp(0.75rem, 1.5vw, 1.25rem);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.page-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(ellipse at center top, rgba(102, 126, 234, 0.1) 0%, transparent 60%);
    pointer-events: none;
}

.page-hero__inner {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin-inline: auto;
}

.page-hero__inner .section-title {
    white-space: nowrap;
}

/* ---- Подвал ---- */
.site-footer {
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    margin-top: auto;
}

.footer-inner {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: 3rem;
    align-items: start;
    padding-block: 3rem;
}

.footer-brand {
    max-width: 320px;
}

.footer-tagline {
    margin-top: 0.75rem;
    font-size: 0.9rem;
    color: var(--text-muted);
    max-width: none;
}

.footer-nav__list {
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

.footer-nav__list a {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.footer-nav__list a:hover {
    color: var(--text-primary);
}

.footer-contact__label {
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    max-width: none;
}

.footer-contact__email {
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

.footer-contact__email:hover {
    color: var(--accent-purple);
}

.footer-bottom {
    border-top: 1px solid var(--color-border);
    padding-block: 1.25rem;
}

.footer-copyright {
    font-size: 0.875rem;
    color: var(--text-muted);
    max-width: none;
}

/* ============================================================
   Адаптивность
   ============================================================ */

/* Планшет и меньше (≤ 900px) */
@media (max-width: 900px) {
    .site-nav {
        /* Мобильное меню — выдвигается вниз */
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 1rem;
        background: rgba(15, 15, 19, 0.98);
        backdrop-filter: blur(16px);
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-110%);
        opacity: 0;
        pointer-events: none;
        transition: transform var(--transition-base), opacity var(--transition-base);
        margin-left: 0;
    }

    .site-nav.site-nav--open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: all;
    }

    .nav-link {
        padding: 0.875rem 1rem;
        font-size: 1rem;
    }

    .nav-toggle {
        display: flex;
    }

    .header-inner {
        gap: 1rem;
    }
}

/* Мобильный (≤ 600px) */
@media (max-width: 600px) {
    .footer-inner {
        grid-template-columns: 1fr;
        gap: 2rem;
        padding-block: 2rem;
    }

    .lang-switcher {
        margin-left: auto;
    }
}