/* ============================================
   COMPONENTS — Header, Footer, Card, Pill, Button
   KHÔNG chỉnh sửa file này khi thêm bài viết.
   ============================================ */

/* HEADER / NAV */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-bg);
  transition: box-shadow 0.3s ease;
}

.header--scrolled {
  box-shadow: 0 1px 0 var(--color-border);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.logo:hover { color: var(--color-primary); }

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--sp-5);
}

.nav__link {
  position: relative;
  font-family: var(--font-utility);
  font-size: 15px;
  font-weight: 500;
  color: var(--color-ink-soft);
  text-decoration: none;
  padding-bottom: var(--sp-1);
  transition: color 0.2s ease;
}

.nav__link:hover { color: var(--color-primary); }

.nav__link--active {
  color: var(--color-primary);
}

.nav__search,
.header__search-mobile {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  color: var(--color-ink-soft);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav__search:hover,
.header__search-mobile:hover {
  background-color: var(--color-bg-alt);
  color: var(--color-primary);
}

.nav__search svg,
.header__search-mobile svg { width: 20px; height: 20px; }

.header__search-mobile {
  display: none;
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 5px;
  cursor: pointer;
  z-index: 200;
}

.hamburger__line {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.hamburger.is-active .hamburger__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.is-active .hamburger__line:nth-child(2) { opacity: 0; }

.hamburger.is-active .hamburger__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-overlay { display: none; }

.hero-banner {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 4;
  object-fit: cover;
  border-radius: 10px;
  margin-bottom: 1.5rem;
  opacity: 0.96;
}

/* CATEGORY PILL */
.pill {
  display: inline-flex;
  align-items: center;
  padding: var(--sp-1) var(--sp-3);
  border-radius: var(--radius-pill);
  font-family: var(--font-utility);
  font-size: var(--fs-caption);
  font-weight: 600;
  line-height: 1;
  white-space: nowrap;
  text-decoration: none;
  transition: opacity 0.2s ease;
}

.pill:hover { opacity: 0.85; color: inherit; }

.pill--doi-song {
  background-color: var(--cat-doi-song-bg);
  color: var(--cat-doi-song-text);
}

.pill--cong-nghe {
  background-color: var(--cat-cong-nghe-bg);
  color: var(--cat-cong-nghe-text);
}

.pill--am-thuc {
  background-color: var(--cat-am-thuc-bg);
  color: var(--cat-am-thuc-text);
}

.pill--du-lich {
  background-color: var(--cat-du-lich-bg);
  color: var(--cat-du-lich-text);
}

/* POST CARD */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--sp-5);
}

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  min-height: 220px;
  width: min(100%, 520px);
  margin: 0 auto;
  padding: var(--sp-6) var(--sp-4);
  background: transparent;
  color: var(--color-ink-soft);
}

.empty-state__illustration {
  width: 120px;
  height: auto;
  margin-bottom: var(--sp-3);
  color: var(--color-primary);
  opacity: 0.9;
}

.empty-state__title {
  margin: 0 0 var(--sp-2);
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 2vw, 2rem);
  color: var(--color-primary);
  font-weight: 700;
}

.empty-state__text {
  margin: 0;
  max-width: 360px;
  color: var(--color-ink-soft);
  font-size: 0.96rem;
  line-height: 1.6;
}

.card {
  position: relative;
  background-color: var(--color-bg);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
}

.card__cover-wrap {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
}

.card__cover {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.card:hover .card__cover { transform: scale(1.04); }

.card__pill {
  position: absolute;
  top: var(--sp-3);
  left: var(--sp-3);
  z-index: 2;
}

.card__body {
  padding: var(--sp-4) var(--sp-5) var(--sp-5);
}

.card__title {
  font-family: var(--font-display);
  font-size: var(--fs-h3);
  font-weight: 700;
  color: var(--color-ink);
  margin-bottom: var(--sp-2);
  line-height: 1.3;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card__title a { color: inherit; text-decoration: none; }
.card__title a:hover { color: var(--color-primary); }

.card__excerpt {
  font-size: 15px;
  color: var(--color-ink-soft);
  line-height: 1.55;
  margin-bottom: var(--sp-3);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card__meta {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  font-family: var(--font-utility);
  font-size: var(--fs-caption);
  color: var(--color-muted);
}

.card__meta-dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background-color: var(--color-muted);
}

/* HERO (Post Page) */
.hero {
  padding-top: var(--sp-7);
  padding-bottom: var(--sp-6);
  text-align: center;
}

.hero__pill { margin-bottom: var(--sp-4); }

.hero__title {
  font-family: var(--font-display);
  font-size: var(--fs-h1);
  font-weight: 700;
  color: var(--color-ink);
  max-width: 720px;
  margin: 0 auto var(--sp-4);
  line-height: 1.2;
}

.hero__meta {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--sp-2);
  font-family: var(--font-utility);
  font-size: 14px;
  color: var(--color-muted);
  margin-bottom: var(--sp-6);
}

.hero__meta-dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background-color: var(--color-muted);
}

.hero__cover {
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.hero__cover img {
  width: 100%;
  max-height: 220px;
  height: auto;
  object-fit: contain;
  display: block;
  margin: 0 auto;
}

/* SECTION HEADINGS */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--sp-6);
}

.section-header__title {
  font-family: var(--font-display);
  font-size: var(--fs-h2);
  font-weight: 700;
}

.section-header__link {
  font-family: var(--font-utility);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-primary);
}

/* BUTTONS */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-5);
  border-radius: var(--radius-pill);
  font-family: var(--font-utility);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.2s ease, color 0.2s ease, transform 0.15s ease;
  cursor: pointer;
}

.btn:active { transform: scale(0.97); }

.btn--primary {
  background-color: var(--color-primary);
  color: #fff;
}

.btn--primary:hover {
  background-color: var(--color-primary-hover);
  color: #fff;
}

.btn--outline {
  background-color: transparent;
  color: var(--color-primary);
  border: 1.5px solid var(--color-primary);
}

.btn--outline:hover {
  background-color: var(--color-primary);
  color: #fff;
}

/* FOOTER */
.footer {
  background-color: var(--color-bg-alt);
  padding: var(--sp-7) 0;
  margin-top: auto;
}

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: var(--sp-6);
}

.footer__heading {
  font-family: var(--font-display);
  font-size: var(--fs-h3);
  font-weight: 700;
  margin-bottom: var(--sp-4);
  color: var(--color-ink);
}

.footer__text {
  font-size: 15px;
  color: var(--color-ink-soft);
  line-height: 1.6;
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}

.footer__link {
  font-family: var(--font-utility);
  font-size: 15px;
  color: var(--color-ink-soft);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer__link:hover { color: var(--color-primary); }

.footer__social {
  display: flex;
  gap: var(--sp-3);
}

.footer__social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background-color: var(--color-bg);
  color: var(--color-ink-soft);
  transition: background-color 0.2s ease, color 0.2s ease;
}

.footer__social-link:hover {
  background-color: var(--color-primary);
  color: #fff;
}

.footer__social-link svg { width: 18px; height: 18px; }

.footer__bottom {
  margin-top: var(--sp-7);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-family: var(--font-utility);
  font-size: var(--fs-caption);
  color: var(--color-muted);
}

/* CATEGORY PAGE HEADER */
.category-header {
  padding: var(--sp-7) 0 var(--sp-6);
  text-align: center;
}

.category-header__title {
  font-family: var(--font-display);
  font-size: var(--fs-h1);
  margin-bottom: var(--sp-3);
}

.category-header__desc {
  font-size: var(--fs-body);
  color: var(--color-ink-soft);
  max-width: 540px;
  margin: 0 auto;
}

/* RESPONSIVE — Mobile (<640px) */
@media (max-width: 639px) {
  .header__inner {
    gap: var(--sp-2);
  }

  .header__search-mobile {
    display: flex;
    margin-left: auto;
  }

  .nav__search {
    display: none;
  }

  .hamburger { display: flex; }

  .nav {
    display: none;
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background-color: var(--color-bg);
    border-radius: var(--radius-lg) 0 0 var(--radius-lg);
    box-shadow: -4px 0 24px rgba(36, 31, 43, 0.12);
    padding: 80px var(--sp-5) var(--sp-5);
    transition: right 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 150;
    overflow-y: auto;
  }

  .nav.is-open {
    display: block;
    right: 0;
  }

  .nav__list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--sp-4);
  }

  .nav__link { font-size: 17px; padding: var(--sp-2) 0; }

  .nav-overlay {
    display: block;
    position: fixed;
    inset: 0;
    background-color: rgba(36, 31, 43, 0.3);
    z-index: 140;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.35s ease;
  }

  .nav-overlay.is-visible {
    opacity: 1;
    pointer-events: auto;
  }

  .nav__search { margin-top: var(--sp-4); }
  .footer__grid { grid-template-columns: 1fr; gap: var(--sp-5); }
  .card-grid { grid-template-columns: 1fr; }
}

/* RESPONSIVE — Tablet (640–1024px) */
@media (min-width: 640px) and (max-width: 1024px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .footer__grid { grid-template-columns: 1fr 1fr; }
}

/* ===========================
   SEARCH MODAL
   =========================== */
.search-modal {
  position: fixed;
  inset: 0;
  background-color: rgba(36, 31, 43, 0.4);
  backdrop-filter: blur(4px);
  z-index: 1000;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 100px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.search-modal.is-active {
  opacity: 1;
  pointer-events: auto;
}

.search-modal__inner {
  width: 100%;
  max-width: 600px;
  background-color: var(--color-bg);
  border-radius: var(--radius-md);
  box-shadow: 0 12px 48px rgba(36, 31, 43, 0.15);
  overflow: hidden;
  transform: translateY(-20px);
  transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.search-modal.is-active .search-modal__inner {
  transform: translateY(0);
}

.search-modal__header {
  display: flex;
  align-items: center;
  padding: var(--sp-3) var(--sp-4);
  border-bottom: 1px solid var(--color-border);
}

.search-modal__input {
  flex: 1;
  font-size: 18px;
  padding: var(--sp-2);
  outline: none;
  color: var(--color-ink);
}

.search-modal__close {
  color: var(--color-muted);
  cursor: pointer;
  padding: var(--sp-2);
}

.search-modal__close:hover {
  color: var(--color-primary);
}

.search-modal__results {
  max-height: 60vh;
  overflow-y: auto;
  padding: var(--sp-2);
}

.search-result {
  display: block;
  padding: var(--sp-3);
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--color-ink);
  transition: background-color 0.2s ease;
}

.search-result:hover {
  background-color: var(--color-bg-alt);
}

.search-result__title {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
}

.search-result__meta {
  font-size: 13px;
  color: var(--color-muted);
}