/* ============================================================
   Cloud Institute — responsive rules (mobile-first refinements)
   Breakpoints: 1080px / 900px / 720px / 520px
   ============================================================ */

@media (max-width: 1080px) {
  .section { padding: 78px 0; }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .footer__grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer__grid > div:last-child { grid-column: 1 / -1; }
  .hero__grid { gap: 40px; }
  .portal { grid-template-columns: 220px 1fr; }
}

@media (max-width: 900px) {
  :root { --header-h: 68px; }

  .hamburger { display: block; }

  .nav-menu {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 18px 20px 26px;
    background: var(--card);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    transform: translateY(-14px);
    opacity: 0;
    visibility: hidden;
    transition: transform var(--t), opacity var(--t), visibility var(--t);
  }
  .nav-menu.is-open { transform: translateY(0); opacity: 1; visibility: visible; }
  .nav-menu a { padding: 14px 12px; font-size: 1rem; border-radius: var(--radius-sm); }
  .nav-menu a::after { display: none; }
  .nav-menu a.is-active { background: var(--gradient-soft); }

  .nav-actions .btn { display: none; }

  [data-reveal="left"],
  [data-reveal="right"] { transform: translateY(28px); }

  .hero { padding: calc(var(--header-h) + 64px) 0 74px; }
  .hero__grid { grid-template-columns: 1fr; }
  .hero__visual { order: -1; }
  .hero__chip--b { left: 0; }

  .split { grid-template-columns: 1fr; gap: 36px; }
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .verify-grid,
  .contact-grid { grid-template-columns: 1fr; }
  .newsletter { grid-template-columns: 1fr; padding: 40px 30px; }

  .portal { grid-template-columns: 1fr; }
  .portal > * { min-width: 0; }
  .portal-side { position: static; min-width: 0; overflow: hidden; }
  .portal-nav {
    grid-auto-flow: column;
    grid-auto-columns: max-content;
    overflow-x: auto;
    gap: 8px;
    padding-bottom: 6px;
    -webkit-overflow-scrolling: touch;
  }
  .portal-nav button { white-space: nowrap; }
}

@media (max-width: 720px) {
  .section { padding: 62px 0; }
  .section-head { margin-bottom: 40px; }

  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }

  .footer__grid { grid-template-columns: 1fr 1fr; }
  .footer__grid > div:first-child { grid-column: 1 / -1; }
  .footer__bottom { flex-direction: column; text-align: center; }
  .footer .social-row { justify-content: center; }

  .list-row { flex-wrap: wrap; }
  .list-row .when { min-width: 0; }
  .panel-block { padding: 20px; }

  .testimonial { padding: 28px 22px; }
  .testimonial blockquote { font-size: 1rem; }

  .newsletter form { flex-direction: column; }
  .newsletter .btn { width: 100%; }

  .hero__proof { gap: 20px; }
  .hero__chip { position: static; margin-top: 14px; display: inline-flex; }
  .hero__panel { padding: 22px; }

  .to-top { right: 16px; bottom: 16px; }
  .toasts { right: 16px; left: 16px; bottom: 76px; width: auto; }
}

@media (max-width: 520px) {
  body { font-size: 15px; }
  .container { width: calc(100% - 32px); }

  .brand small { display: none; }
  .btn { width: 100%; }
  .hero__cta .btn { flex: 1 1 100%; }
  .stats { grid-template-columns: 1fr; }
  .filters { gap: 8px; }
  .filter { padding: 9px 15px; font-size: 0.82rem; }

  .certificate,
  .verify-box,
  .modal__box { padding: 22px; }
  .certificate__row { flex-direction: column; gap: 2px; }
  .certificate__row strong { text-align: left; }

  .instructor-card,
  .value-card { padding: 24px; }
  .newsletter { padding: 32px 22px; }
}

@media print {
  .header, .footer, .to-top, .toasts, .loader, .scroll-progress { display: none !important; }
  body { background: #fff; }
}

@media (max-width: 900px) {
  .pricing { grid-template-columns: 1fr; }
  .pricing__main, .pricing__list { padding: 34px 26px; }
}

@media (max-width: 520px) {
  .course-card__foot { flex-direction: column; align-items: flex-start; gap: 14px; }
  .course-card__foot .btn { width: 100%; }
  .pricing__cta .btn { width: 100%; }
}