/* ============================================================
   YunZhongTech · Component Styles
   ============================================================ */

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-nav);
  padding: var(--space-5) 0;
  transition: all var(--duration-slow) var(--ease-out-quart);
}

.nav.is-scrolled {
  background: rgba(5, 9, 14, 0.82);
  backdrop-filter: blur(24px) saturate(150%);
  -webkit-backdrop-filter: blur(24px) saturate(150%);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-3) 0;
  box-shadow: 0 16px 60px rgba(0, 0, 0, 0.24);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width-lg);
  margin-inline: auto;
  padding-inline: var(--content-padding);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--text-primary);
}

.nav__logo-img {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  object-fit: contain;
  background: rgba(255, 255, 255, 0.92);
  padding: 2px;
  box-shadow: 0 10px 36px rgba(24, 214, 198, 0.12);
}

.nav__logo-text {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-wide);
  color: var(--text-primary);
}

.nav__logo-text span {
  display: block;
  font-size: var(--text-xs);
  font-weight: var(--weight-regular);
  color: var(--text-accent);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav__link {
  position: relative;
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--text-secondary);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  transition: all var(--duration-normal) var(--ease-out-quart);
  text-decoration: none;
}

.nav__link:hover,
.nav__link.is-active {
  color: var(--text-primary);
  background: rgba(184, 217, 255, 0.055);
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--gradient-nebula);
  border-radius: var(--radius-full);
  transition: all var(--duration-normal) var(--ease-out-expo);
  transform: translateX(-50%);
}

.nav__link:hover::after,
.nav__link.is-active::after {
  width: 24px;
}

/* Nav actions */
.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* Language switcher */
.lang-switch {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-1) var(--space-2);
  background: rgba(5, 9, 14, 0.42);
}

.lang-switch__btn {
  background: none;
  border: none;
  color: var(--text-tertiary);
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--duration-fast);
}

.lang-switch__btn.is-active {
  background: rgba(24, 214, 198, 0.14);
  color: var(--text-primary);
}

/* Mobile menu toggle */
.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  z-index: calc(var(--z-nav) + 10);
}

.nav__toggle-line {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
  transition: all var(--duration-normal) var(--ease-out-expo);
  transform-origin: center;
}

.nav__toggle.is-open .nav__toggle-line:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav__toggle.is-open .nav__toggle-line:nth-child(2) {
  opacity: 0;
}

.nav__toggle.is-open .nav__toggle-line:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile menu overlay */
.nav__mobile-menu {
  position: fixed;
  inset: 0;
  background:
    radial-gradient(circle at 50% 18%, rgba(24, 214, 198, 0.12), transparent 18rem),
    rgba(5, 9, 14, 0.97);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  z-index: var(--z-nav);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-6);
  opacity: 0;
  visibility: hidden;
  transition: all var(--duration-slow) var(--ease-out-expo);
}

.nav__mobile-menu.is-open {
  opacity: 1;
  visibility: visible;
}

.nav__mobile-link {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: var(--weight-bold);
  color: var(--text-secondary);
  text-decoration: none;
  transition: all var(--duration-normal);
  transform: translateY(20px);
  opacity: 0;
}

.nav__mobile-menu.is-open .nav__mobile-link {
  transform: translateY(0);
  opacity: 1;
}

.nav__mobile-link:hover {
  color: var(--text-primary);
}

/* Stagger animation for mobile links */
.nav__mobile-link:nth-child(1) { transition-delay: 50ms; }
.nav__mobile-link:nth-child(2) { transition-delay: 100ms; }
.nav__mobile-link:nth-child(3) { transition-delay: 150ms; }
.nav__mobile-link:nth-child(4) { transition-delay: 200ms; }
.nav__mobile-link:nth-child(5) { transition-delay: 250ms; }
.nav__mobile-link:nth-child(6) { transition-delay: 300ms; }


/* ── Cards ── */
.card {
  position: relative;
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: var(--glass-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all var(--duration-slow) var(--ease-out-expo);
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background:
    linear-gradient(135deg, rgba(232, 207, 131, 0.07), transparent 36%),
    linear-gradient(315deg, rgba(24, 214, 198, 0.08), transparent 42%);
  opacity: 0;
  transition: opacity var(--duration-slow);
}

.card:hover {
  border-color: var(--color-border-glow);
  transform: translateY(-5px);
  box-shadow: var(--shadow-glow);
}

.card:hover::before {
  opacity: 1;
}

.card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: rgba(24, 214, 198, 0.1);
  color: var(--accent-cyan);
  font-size: var(--text-2xl);
  margin-bottom: var(--space-6);
}

.card__title {
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-3);
}

.card__desc {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  line-height: var(--leading-relaxed);
}

.card__link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin-top: var(--space-6);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--text-accent);
  transition: gap var(--duration-normal);
}

.card__link:hover {
  gap: var(--space-3);
  color: var(--text-highlight);
}

/* Card grid */
.card-grid {
  display: grid;
  gap: var(--space-6);
}

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


/* ── Stats / Counter ── */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-8);
}

.stat {
  text-align: center;
  padding: var(--space-8);
  border: 1px solid rgba(184, 217, 255, 0.08);
  background: rgba(9, 22, 34, 0.42);
  border-radius: var(--radius-xl);
}

.stat__number {
  font-family: var(--font-display);
  font-size: var(--text-6xl);
  font-weight: var(--weight-black);
  line-height: 1;
  margin-bottom: var(--space-2);
}

.stat__label {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  letter-spacing: var(--tracking-wide);
}

.stat__unit {
  font-size: var(--text-2xl);
  font-weight: var(--weight-regular);
  color: var(--text-tertiary);
}


/* ── News Card ── */
.news-card {
  display: flex;
  flex-direction: column;
  background: linear-gradient(180deg, rgba(14, 34, 49, 0.72), rgba(7, 15, 24, 0.82));
  border: var(--glass-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all var(--duration-slow) var(--ease-out-expo);
}

.news-card:hover {
  border-color: var(--color-border-glow);
  transform: translateY(-6px);
  box-shadow: var(--shadow-glow);
}

.news-card__img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  transition: transform var(--duration-slow);
  filter: saturate(0.92) contrast(1.04);
}

.news-card:hover .news-card__img {
  transform: scale(1.05);
}

.news-card__img-wrapper {
  overflow: hidden;
  position: relative;
}

.news-card__img-wrapper::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 48%, rgba(5, 9, 14, 0.62));
  pointer-events: none;
}

.news-card__body {
  padding: var(--space-6);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.news-card__date {
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  font-family: var(--font-mono);
  margin-bottom: var(--space-3);
}

.news-card__title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-3);
  line-height: var(--leading-snug);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-card__excerpt {
  font-size: var(--text-sm);
  color: var(--text-tertiary);
  line-height: var(--leading-normal);
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-card__link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--text-accent);
}


/* ── Footer ── */
.footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-16) 0 var(--space-8);
  background:
    radial-gradient(circle at 18% 0%, rgba(24, 214, 198, 0.08), transparent 28rem),
    linear-gradient(180deg, rgba(8, 17, 26, 0.6), #05070b);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer__brand-desc {
  font-size: var(--text-sm);
  color: var(--text-tertiary);
  line-height: var(--leading-relaxed);
  margin-top: var(--space-4);
  max-width: 320px;
}

.footer__col-title {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--text-primary);
  letter-spacing: var(--tracking-wide);
  margin-bottom: var(--space-4);
}

.footer__link {
  display: block;
  font-size: var(--text-sm);
  color: var(--text-tertiary);
  padding: var(--space-1) 0;
  transition: color var(--duration-fast);
}

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

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-border);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
}

.footer__bottom a {
  color: var(--text-tertiary);
}

.footer__bottom a:hover {
  color: var(--text-accent);
}


/* ── Loading Skeleton ── */
.skeleton {
  background: linear-gradient(90deg,
    var(--color-surface) 25%,
    var(--color-surface-alt) 50%,
    var(--color-surface) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-shimmer {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton--text {
  height: 1em;
  margin-bottom: var(--space-2);
}

.skeleton--title {
  height: 1.5em;
  width: 60%;
  margin-bottom: var(--space-4);
}

.skeleton--img {
  aspect-ratio: 16 / 9;
}


/* ── Breadcrumb ── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--text-tertiary);
  padding: var(--space-4) 0;
}

.breadcrumb a {
  color: var(--text-tertiary);
  transition: color var(--duration-fast);
}

.breadcrumb a:hover {
  color: var(--text-accent);
}

.breadcrumb__separator {
  color: var(--text-tertiary);
  opacity: 0.5;
}

.breadcrumb__current {
  color: var(--text-secondary);
}


/* ── Page Hero (sub-pages) ── */
.page-hero {
  position: relative;
  padding: calc(var(--space-32) + 80px) 0 var(--space-20);
  text-align: center;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at center top, rgba(24, 214, 198, 0.1) 0%, transparent 60%),
    linear-gradient(rgba(184, 217, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(184, 217, 255, 0.025) 1px, transparent 1px);
  background-size: auto, 72px 72px, 72px 72px;
  pointer-events: none;
}

.page-hero__title {
  font-size: var(--text-5xl);
  margin-bottom: var(--space-4);
  letter-spacing: 0;
}

.page-hero__subtitle {
  font-size: var(--text-lg);
  color: var(--text-secondary);
  max-width: 600px;
  margin-inline: auto;
}


/* ── Timeline ── */
.timeline {
  position: relative;
  padding-left: var(--space-8);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg,
    var(--accent-indigo) 0%,
    var(--accent-cyan) 50%,
    transparent 100%);
}

.timeline__item {
  position: relative;
  padding-bottom: var(--space-12);
}

.timeline__item::before {
  content: '';
  position: absolute;
  left: calc(-1 * var(--space-8) - 5px);
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent-indigo);
  box-shadow: 0 0 12px rgba(99, 102, 241, 0.4);
}

.timeline__year {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--text-accent);
  letter-spacing: var(--tracking-wider);
  margin-bottom: var(--space-2);
}

.timeline__title {
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-2);
}

.timeline__desc {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}


/* ── Pagination ── */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-12);
}

.pagination__btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--text-secondary);
  font-size: var(--text-sm);
  cursor: pointer;
  transition: all var(--duration-fast);
}

.pagination__btn:hover {
  border-color: var(--accent-indigo);
  color: var(--text-primary);
}

.pagination__btn.is-active {
  background: var(--accent-indigo);
  border-color: var(--accent-indigo);
  color: #fff;
}