.mobile-nav {
    display: none;
    position: fixed;
    top: 96px;
    left: 50%;
    transform: translateX(-50%) translateY(-12px);
    width: min(92%, 420px);
    background: rgba(12, 11, 16, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-md);
    padding: 10px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease, transform 0.3s ease;
    z-index: 999;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
}

.mobile-nav.active {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
    pointer-events: all;
}

.mobile-nav a {
    display: block;
    padding: 14px 18px;
    color: var(--ink);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    font-family: var(--font-display);
    border-radius: var(--radius-sm);
    transition: background 0.2s ease, color 0.2s ease;
}

.mobile-nav a:hover { background: rgba(138, 43, 226, 0.12); color: var(--violet-light); }
.mobile-nav a.nav_main { color: var(--violet-light); background: rgba(138, 43, 226, 0.08); }

@media (max-width: 900px) {
    .container#about { margin-top: 40px; }

    .hero-title { font-size: 3rem; }

    .section, .section.reverse { flex-direction: column; }

    .image-placeholder { width: 100%; }

    .roadmap-item, .roadmap-item.left, .roadmap-item.right {
        width: 100%;
        left: 0;
        padding-left: 50px;
        padding-right: 0;
        text-align: left;
    }

    .roadmap-line { left: 16px; }
    .left .roadmap-dot, .right .roadmap-dot { left: 8px; right: auto; }

    .footer-container { grid-template-columns: 1fr 1fr; }
    .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 768px) {
    header nav { display: none; }
    .burger-menu { display: flex; }

    header { padding: 0 8px 0 8px; height: 62px; }
    .lang-select { padding: 8px 26px 8px 12px; font-size: 12px; }
    .auth-icon-btn { width: 36px; height: 36px; }

    .mobile-nav { top: 84px; }

    .hero { padding-top: 120px; }
    .hero-hud { top: 92px; }
    .hero-title { font-size: 2.3rem; letter-spacing: 1.5px; }
    .hero-subtitle { font-size: 1.05rem; }

    .hero-btns { flex-direction: column; gap: 14px; align-items: center; }
    .btn-primary, .btn-secondary { width: 220px; text-align: center; }

    h2 { font-size: 1.7rem; }

    .stats-grid { grid-template-columns: 1fr; }
    .stat-number { font-size: 2.3rem; }

    .socials-grid { flex-direction: column; align-items: center; }
    .social-item { width: 220px; justify-content: center; }

    .footer-container { grid-template-columns: 1fr; text-align: center; gap: 40px; }
    .footer-brand .logo { margin: 0 auto 20px; }
    .footer-desc { max-width: 100%; margin: 0 auto; }
    .footer ul { display: flex; flex-wrap: wrap; justify-content: center; gap: 18px; }
    .footer ul li { margin: 0; }

    .back-to-top { width: 46px; height: 46px; bottom: 20px; right: 20px; }

    .btn-primary-sos { font-size: 1.1rem; padding: 18px 30px; }
}

@media (max-width: 480px) {
    .container { padding: 0 16px; }
    .container#about { margin-top: 30px; }
    .hero-title { font-size: 1.9rem; }
    .compat-strip { display: none; }
}

@media (max-height: 520px) and (orientation: landscape) {
    .hero { min-height: auto; padding: 130px 20px 60px; }
    .hero-title { font-size: 2.2rem; }
    .mobile-nav { max-height: 70vh; overflow-y: auto; }
}