/* ============================================
   COMPONENTS.CSS — Các thành phần dùng lại
   Sửa: button, nav underline, fade-up, focus, hamburger
   ============================================ */

/* === Animations chung === */
.fade-up {
  opacity: 0;
  will-change: opacity, transform;
  transform: translateY(36px);
  transition:
    opacity 0.41s cubic-bezier(0.32, 0, 0.26, 1),
    transform 0.61s cubic-bezier(0.32, 0, 0.26, 1);
}
.fade-up.in {
  opacity: 1 !important;
  transform: translateY(0) !important;
}

/* Layer optimize cho mobile */
.fade-up,
.logo-char,
.crossfade-img,
.gallery-img {
  will-change: opacity, transform;
  backface-visibility: hidden;
}

/* === Tap feedback === */
.touch-scale:active {
  transform: scale(0.97);
  transition: transform 100ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* === Focus ring (accessibility) === */
.focus-ring:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}

/* === Hide scrollbar === */
.hide-scrollbar::-webkit-scrollbar {
  display: none;
}
.hide-scrollbar {
  -ms-overflow-style: none;
  scrollbar-width: none;
}
.hide-scrollbar,
.hide-scrollbar * {
  -webkit-overflow-scrolling: touch !important;
}

/* === Nav underline animation (desktop) === */
.nav-anim-underline {
  position: relative;
  overflow: hidden;
}
.nav-anim-underline::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1.5px;
  background: var(--ink);
  transform: scaleX(0);
  transition: transform 0.22s cubic-bezier(0.32, 0, 0.26, 1);
  transform-origin: left;
}
@media (pointer: fine) {
  .nav-anim-underline:hover::after,
  .nav-anim-underline:focus::after {
    transform: scaleX(1);
  }
}

/* === Hamburger bars === */
.hamburger-bar {
  display: block;
  width: 28px;
  height: 2.5px;
  margin: 4px 0;
  background: var(--ink);
  border-radius: 2px;
  transition: all 0.25s cubic-bezier(0.32, 0, 0.26, 1);
}