.overlay-scroll-target {
  scrollbar-gutter: auto !important;
  scrollbar-width: none !important;
  -ms-overflow-style: none;
}

.overlay-scroll-target::-webkit-scrollbar {
  display: none !important;
  inline-size: 0 !important;
  block-size: 0 !important;
}

.overlay-scrollbar-layer {
  position: fixed;
  z-index: 1300;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

/* 최상위 레이어로 올렸을 때 브라우저 기본 [popover] 모양(테두리·여백·배경)을 지운다.
   화면 전체를 덮는 투명한 판이어야 하고, 클릭은 통과시켜야 한다. */
.overlay-scrollbar-layer[popover] {
  inset: 0;
  inline-size: auto;
  block-size: auto;
  max-inline-size: none;
  max-block-size: none;
  margin: 0;
  padding: 0;
  border: 0;
  background: transparent;
  overflow: hidden;
  pointer-events: none;
}

.overlay-scrollbar {
  position: absolute;
  inline-size: 0.75rem;
  border-radius: var(--radius-pill);
  opacity: 0;
  outline: 0;
  pointer-events: none;
  touch-action: none;
  transition: opacity var(--motion-standard) ease-in-out;
}

.overlay-scrollbar[hidden] {
  display: none;
}

.overlay-scrollbar::before {
  position: absolute;
  inset: 0 3px;
  border-radius: inherit;
  background: transparent;
  content: "";
  transition: background-color var(--motion-micro) var(--ease-out);
}

.overlay-scrollbar__thumb {
  position: absolute;
  inset-block-start: 0;
  inset-inline: 4px;
  min-block-size: 2rem;
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--text-tertiary) 62%, transparent);
  transition:
    inset var(--motion-micro) var(--ease-out),
    background-color var(--motion-micro) var(--ease-out);
}

.overlay-scrollbar:is(.is-scrolling, .is-dragging) {
  opacity: 0.68;
  pointer-events: auto;
}

.overlay-scrollbar:is(.is-scrolling:hover, .is-dragging) {
  opacity: 1;
}

.overlay-scrollbar:is(.is-scrolling:hover, .is-dragging)::before {
  background: color-mix(in srgb, var(--border-default) 34%, transparent);
}

.overlay-scrollbar:is(.is-scrolling:hover, .is-dragging) .overlay-scrollbar__thumb {
  inset-inline: 2px;
  background: color-mix(in srgb, var(--text-secondary) 82%, transparent);
}

@media (pointer: coarse) {
  .overlay-scrollbar:is(.is-scrolling, .is-dragging) {
    opacity: 0.78;
  }

  .overlay-scrollbar__thumb {
    inset-inline: 3px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .overlay-scrollbar,
  .overlay-scrollbar::before,
  .overlay-scrollbar__thumb {
    transition: none;
  }
}