/*
 * SplitPane
 *
 * Two panes and the divider between them. The first pane's share comes in as
 * `--ion-split-pane-size`; the second takes the rest. Each pane scrolls on
 * its own, and neither can be widened by what is in it (`min-width: 0`).
 *
 * The divider is one line of border/default with a 16px target around it,
 * and a grip at its middle in icon/secondary — the line alone is a border,
 * and says nothing about being movable; the grip does, at 3:1. The line goes
 * to border/strong on hover, and both to border/focus while focused or
 * dragged.
 */
.ion-split-pane {
  display: flex;
  min-width: 0;
  min-height: 0;
}

.ion-split-pane--vertical {
  flex-direction: column;
  height: 100%;
}

.ion-split-pane__pane {
  min-width: 0;
  min-height: 0;
  overflow: auto;
}

.ion-split-pane__start {
  flex: 0 0 var(--ion-split-pane-size, 50%);
}

.ion-split-pane__end {
  flex: 1 1 0;
}

/* Room either side of the divider, so neither pane's content touches it. */
.ion-split-pane--horizontal > .ion-split-pane__start {
  padding-inline-end: var(--spacing-12);
}

.ion-split-pane--horizontal > .ion-split-pane__end {
  padding-inline-start: var(--spacing-12);
}

.ion-split-pane--vertical > .ion-split-pane__start {
  padding-block-end: var(--spacing-12);
}

.ion-split-pane--vertical > .ion-split-pane__end {
  padding-block-start: var(--spacing-12);
}

.ion-split-pane__divider {
  position: relative;
  flex: none;
  background-color: var(--border-default);
  touch-action: none;
  transition: background-color var(--ion-duration-base) var(--ion-ease-out);
}

.ion-split-pane--horizontal > .ion-split-pane__divider {
  width: var(--border-width-default);
  cursor: col-resize;
}

.ion-split-pane--vertical > .ion-split-pane__divider {
  height: var(--border-width-default);
  cursor: row-resize;
}

/* The target: 16px across the line, centred on it. */
.ion-split-pane__divider::before {
  position: absolute;
  z-index: 1;
  content: '';
}

.ion-split-pane--horizontal > .ion-split-pane__divider::before {
  top: 0;
  bottom: 0;
  inset-inline-start: calc(var(--spacing-8) * -1);
  width: var(--spacing-16);
}

.ion-split-pane--vertical > .ion-split-pane__divider::before {
  inset-inline: 0;
  top: calc(var(--spacing-8) * -1);
  height: var(--spacing-16);
}

/* The grip: a short bar across the middle of the line. */
.ion-split-pane__divider::after {
  position: absolute;
  inset: 50% auto auto 50%;
  border-radius: var(--radius-full);
  background-color: var(--icon-secondary);
  content: '';
  translate: -50% -50%;
}

.ion-split-pane--horizontal > .ion-split-pane__divider::after {
  width: var(--spacing-4);
  height: var(--spacing-24);
}

.ion-split-pane--vertical > .ion-split-pane__divider::after {
  width: var(--spacing-24);
  height: var(--spacing-4);
}

.ion-split-pane__divider:focus-visible::after,
.ion-split-pane__divider[data-resizing='true']::after {
  background-color: var(--border-focus);
}

@media (hover: hover) {
  .ion-split-pane__divider:hover {
    background-color: var(--border-strong);
  }
}

.ion-split-pane__divider:focus-visible,
.ion-split-pane__divider[data-resizing='true'] {
  background-color: var(--border-focus);

  /* Focus and a drag show at once: this colour is the focus indicator. */
  transition: none;
}

.ion-split-pane__divider:focus-visible {
  outline: var(--border-width-thick) solid var(--ring-focus);
  outline-offset: var(--border-width-thick);
}

/*
 * Stacked at the collapse breakpoint, Grid's: the divider goes, and with it
 * its tab stop, and each pane takes the height its content needs.
 */
@media (width <= 1023px) {
  .ion-split-pane--collapse-tablet {
    flex-direction: column;
    gap: var(--spacing-12);
  }

  .ion-split-pane--collapse-tablet > .ion-split-pane__divider {
    display: none;
  }

  .ion-split-pane--collapse-tablet > .ion-split-pane__pane {
    flex: none;
    padding: 0;
    overflow: visible;
  }
}

@media (width <= 767px) {
  .ion-split-pane--collapse-mobile {
    flex-direction: column;
    gap: var(--spacing-12);
  }

  .ion-split-pane--collapse-mobile > .ion-split-pane__divider {
    display: none;
  }

  .ion-split-pane--collapse-mobile > .ion-split-pane__pane {
    flex: none;
    padding: 0;
    overflow: visible;
  }
}

@media (forced-colors: active) {
  .ion-split-pane__divider,
  .ion-split-pane__divider::after {
    background-color: CanvasText;
  }

  .ion-split-pane__divider:focus-visible,
  .ion-split-pane__divider[data-resizing='true'],
  .ion-split-pane__divider:focus-visible::after,
  .ion-split-pane__divider[data-resizing='true']::after {
    background-color: Highlight;
  }
}