/* ==========================================================================
   responsive.css - Desktop-first, bám theo mockup ở 1536px rồi thu nhỏ dần.
   Container luôn co lại theo viewport, không bao giờ gây cuộn ngang.
   ========================================================================== */

/* ================================================= <= 1360px : desktop nhỏ */
@media (max-width: 1360px) {
  :root {
    --container-gutter: 28px;
  }

  .youtube__grid {
    grid-template-columns: minmax(0, 1fr) 380px 280px;
    column-gap: 20px;
  }

  .video-list__item {
    grid-template-columns: 116px minmax(0, 1fr);
  }

  .news-list__item {
    grid-template-columns: 150px minmax(0, 1fr);
  }
}

/* ============================================ <= 1180px : laptop / tablet ngang */
@media (max-width: 1180px) {
  :root {
    --fs-h1: 40px;
    --fs-h2: 28px;
    --container-gutter: var(--container-gutter-md);
  }

  .hero {
    min-height: 340px;
  }

  .hero__media {
    background-position: 84% center;
  }

  /* Ảnh bị cắt hẹp hơn nên cần lớp chuyển tiếp mạnh hơn để chữ luôn đọc rõ */
  .hero__media::after {
    background-image: linear-gradient(
      90deg,
      rgba(250, 249, 246, 0.96) 0%,
      rgba(250, 249, 246, 0.87) 34%,
      rgba(250, 249, 246, 0.45) 58%,
      rgba(250, 249, 246, 0) 76%
    );
  }

  .hero__quote {
    display: none;
  }

  .hero__inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .roadmap__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 20px;
    row-gap: 22px;
  }

  .roadmap__arrow {
    display: none;
  }

  .roadmap__note span {
    font-size: 28px;
  }

  .courses__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .youtube__grid {
    grid-template-columns: minmax(0, 1fr) 300px;
    row-gap: 22px;
  }

  .youtube__intro {
    grid-column: 1 / -1;
    max-width: none;
  }

  .news__grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .news__aside {
    align-items: flex-start;
  }

  .cta-band__inner {
    grid-template-columns: 200px minmax(0, 1fr);
    row-gap: 16px;
  }

  .cta-band__features {
    grid-column: 1 / -1;
    justify-content: center;
  }

  .site-footer__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }

  .site-footer__quote {
    text-align: left;
  }

  .site-footer__policy {
    justify-content: flex-start;
  }

  .site-footer__meta {
    flex-wrap: wrap;
  }

  .site-footer__copyright {
    white-space: normal;
  }

  .post-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .content-layout {
    grid-template-columns: minmax(0, 1fr) 290px;
    gap: 32px;
  }
}

/* ================================================== <= 1024px : tablet dọc */
@media (max-width: 1024px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-header__inner {
    gap: 14px;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: none;
    padding: 12px var(--container-gutter-md) 20px;
    background-color: #fff;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
  }

  .site-nav.is-open {
    display: block;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__link {
    display: block;
    padding: 12px 4px;
    font-size: var(--fs-body);
    border-bottom: 1px solid var(--color-border-soft);
  }

  .site-nav__link::after {
    display: none;
  }

  .site-header__actions {
    margin-left: auto;
    gap: 12px;
  }

  .stats__list {
    flex-wrap: wrap;
  }

  .stats__item {
    flex: 1 1 46%;
    padding: 10px 0 10px 18px;
  }

  .stats__item:nth-child(odd) {
    border-left: 0;
    padding-left: 4px;
  }

  .stats__item:nth-child(n + 3) {
    border-top: 1px solid var(--color-border-soft);
  }

  .content-layout,
  .content-layout--reverse {
    grid-template-columns: minmax(0, 1fr);
  }

  .sidebar {
    position: static;
  }

  .search-result {
    grid-template-columns: 160px minmax(0, 1fr);
  }

  .feature-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ======================================================== <= 860px : mobile ngang */
@media (max-width: 860px) {
  :root {
    --fs-h1: 34px;
    --fs-h2: 25px;
    --fs-lead: 16px;
    --container-gutter: var(--container-gutter-sm);
  }

  .hero {
    min-height: 0;
  }

  .hero__media {
    background-position: 78% center;
  }

  .hero__media::after {
    background-image: linear-gradient(
      90deg,
      rgba(250, 249, 246, 0.97) 0%,
      rgba(250, 249, 246, 0.9) 46%,
      rgba(250, 249, 246, 0.5) 74%,
      rgba(250, 249, 246, 0.25) 100%
    );
  }

  .hero__inner {
    padding-block: 34px 38px;
  }

  .roadmap__head {
    flex-direction: column;
    gap: 12px;
  }

  .roadmap__note {
    align-self: flex-end;
  }

  .youtube__grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .news-featured {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }

  .news-featured__body {
    padding-top: 0;
  }

  .news-featured__media img {
    aspect-ratio: 16 / 10;
  }

  .section__head--row {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .cta-band {
    padding-block: 26px 22px;
  }

  .cta-band__inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .cta-band__decor {
    opacity: 0.35;
  }

  .cta-band__features {
    grid-column: auto;
  }

  .post-header__title {
    font-size: 28px;
  }

  .page-hero__title {
    font-size: 27px;
  }

  .search-result {
    grid-template-columns: 140px minmax(0, 1fr);
    gap: 16px;
  }
}

/* ============================================================ <= 620px : mobile */
@media (max-width: 620px) {
  :root {
    --fs-h1: 30px;
    --fs-h2: 23px;
    --fs-h3: 19px;
  }

  .site-logo img {
    height: 34px;
  }

  .site-header__actions .btn {
    padding: 0 14px;
    font-size: var(--fs-xs);
  }

  .hero__actions .btn {
    flex: 1 1 100%;
  }

  .hero__usp {
    gap: 8px 18px;
  }

  .stats__item,
  .stats__item + .stats__item {
    flex: 1 1 100%;
    border-left: 0;
    padding-left: 4px;
  }

  .stats__item + .stats__item {
    border-top: 1px solid var(--color-border-soft);
  }

  .roadmap__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .roadmap__figure {
    height: 76px;
    padding-left: 10px;
  }

  .courses__grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .video-list__item,
  .news-list__item {
    grid-template-columns: 116px minmax(0, 1fr);
    gap: 12px;
  }

  .video-card__title {
    right: 74px;
    font-size: var(--fs-body);
  }

  .site-footer__grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .post-grid,
  .feature-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .cta-band__actions .btn {
    flex: 1 1 100%;
  }

  .search-result {
    grid-template-columns: minmax(0, 1fr);
  }

  .search-result__media {
    max-width: 260px;
  }

  .search-form {
    flex-wrap: wrap;
  }

  .search-form .input {
    flex: 1 1 100%;
  }
}

/* ============================================ <= 420px : mobile nhỏ */
@media (max-width: 420px) {
  .roadmap__list {
    grid-template-columns: minmax(0, 1fr);
  }

  .video-list__item,
  .news-list__item {
    grid-template-columns: minmax(0, 1fr);
  }

  .video-list__thumb,
  .news-list__thumb {
    max-width: 220px;
  }
}