/* ════════════════════════════════════════════════════════════
   ACER CHESS ACADEMY — responsive.css
   Breakpoints: tablet (≤900px) · mobile (≤640px)
   ════════════════════════════════════════════════════════════ */

/* ── Hamburger visible on mobile ───────────────────────────── */
@media (max-width: 860px) {
  .nav-hamburger { display: flex; }

  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    background: rgba(250, 247, 244, 0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: stretch;
    padding: 1.25rem;
    gap: 0.25rem;
    box-shadow: 0 8px 32px rgba(0,0,0,0.1);
    border-top: 1px solid var(--border);
    transform: translateY(-110%);
    opacity: 0;
    pointer-events: none;
    transition:
      transform var(--dur-med) var(--ease-out-expo),
      opacity var(--dur-med) var(--ease-out-expo);
    z-index: 999;
  }
  .nav-links.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-link {
    padding: 0.875rem 1rem;
    font-size: 0.875rem;
    border-radius: var(--radius-sm);
    text-align: center;
  }
  .nav-link--cta {
    margin-top: 0.5rem;
    text-align: center;
  }
}

/* ── Hero — tablet ─────────────────────────────────────────── */
@media (max-width: 900px) {
  .hero__inner {
    grid-template-columns: 1fr;
    align-items: center;
    min-height: calc(100svh - var(--nav-h));
    padding-bottom: 5rem;
  }

  .hero__player-stack--left,
  .hero__player-stack--right {
    display: none;
  }

  .hero__center {
    grid-column: 1;
    min-height: calc(100svh - var(--nav-h));
    padding: var(--space-md) clamp(1rem, 4vw, 2rem);
  }
}

/* ── Hero — mobile ─────────────────────────────────────────── */
@media (max-width: 640px) {
  .hero__title-brand {
    font-size: clamp(3rem, 14vw, 4.5rem);
  }
  .hero__cta-group {
    flex-direction: column;
    align-items: center;
  }
  .hero__cta-group .btn {
    width: 100%;
    max-width: 280px;
  }
  .hero__bg-logo {
    width: clamp(200px, 70vw, 320px);
    height: clamp(200px, 70vw, 320px);
  }
}

/* ── About — tablet ────────────────────────────────────────── */
@media (max-width: 820px) {
  .about__layout {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }
  .about__right {
    order: -1;
  }
  .about__brand-img-wrap {
    max-width: 180px;
  }
}

/* ── Contact — mobile ──────────────────────────────────────── */
@media (max-width: 700px) {
  .contact__layout {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
}

/* ── Footer socials on small screens ──────────────────────── */
@media (max-width: 480px) {
  .footer__socials { gap: 0.375rem; }
  .footer__social-btn { width: 36px; height: 36px; }
  .footer__nav { gap: 0; }
}

/* ── Prevent overflow ──────────────────────────────────────── */
@media (max-width: 1024px) {
  .hero { overflow-x: hidden; }
  .services::before,
  .testimonials::after { display: none; }
}