body.scroll-ball-page {
  --global-theme-color: #0a8645;
  --global-hover-color: #0a8645;
  --ball-accent: #3ddc84;
  --ball-size: 3.9rem;
  --ball-gutter: 2.75rem;
  --ball-shade: 0.3;
}

html[data-theme="dark"] body.scroll-ball-page {
  --global-theme-color: #3ddc84;
  --global-hover-color: #3ddc84;
  --ball-shade: 0.6;
}

body.scroll-ball-active {
  position: relative;
  isolation: isolate;
}

body.scroll-ball-active .container[role="main"] {
  position: relative;
}

/* Keep the card background below the ink and the readable content above it. */
body.scroll-ball-active .container[role="main"] > .post > * {
  position: relative;
  z-index: 2;
}

body.scroll-ball-page .runout {
  height: 0;
  pointer-events: none;
}

body.scroll-ball-active .runout {
  height: 100dvh;
}

.ball__trail {
  position: absolute;
  z-index: 1;
  inset: 0 auto auto 0;
  width: 100%;
  height: 100dvh;
  pointer-events: none;
}

.ball__sphere,
.ball__handle {
  position: fixed;
  inset: 0 auto auto 0;
  width: var(--ball-size);
  height: var(--ball-size);
}

.ball__sphere {
  z-index: 80;
  pointer-events: none;
}

.ball__sphere--grounded {
  filter: drop-shadow(var(--contact-x, 1px) var(--contact-y, 1.5px) 1.5px rgb(0 0 0 / calc(var(--ball-shade) * var(--contact, 1))));
}

.ball__handle {
  z-index: 81;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: transparent;
  cursor: pointer;
}

.ball__handle:disabled {
  cursor: default;
}

.ball__handle:focus-visible,
.ball__settings-trigger:focus-visible,
.ball__settings :focus-visible {
  outline: 2px solid var(--ball-accent);
  outline-offset: 0.25rem;
}

.ball__shadow {
  position: fixed;
  z-index: 79;
  inset: 0 auto auto 0;
  width: calc(var(--ball-size) * 1.5);
  height: calc(var(--ball-size) * 1.5);
  border-radius: 50%;
  background: radial-gradient(
    closest-side,
    rgb(0 0 0 / var(--ball-shade)),
    rgb(0 0 0 / calc(var(--ball-shade) * 0.5)) 45%,
    rgb(0 0 0 / calc(var(--ball-shade) * 0.15)) 75%,
    transparent
  );
  pointer-events: none;
}

.ball__dock {
  position: fixed;
  z-index: 78;
  inset: 0 auto auto 0;
  width: calc(var(--ball-size) * 0.8 - 2px);
  height: calc(var(--ball-size) * 0.8 - 2px);
  border: 1px solid var(--global-text-color);
  border-radius: 50%;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.ball__dock--visible {
  opacity: 1;
}

.ball__settings {
  position: fixed;
  z-index: 85;
  inset-block-end: calc(var(--ball-gutter) + 2.5rem);
  inset-inline-end: calc(var(--ball-gutter) - 1rem);
  display: grid;
  gap: 0.5em;
  max-width: calc(100vw - 2rem);
  max-height: calc(100dvh - var(--ball-gutter) - 3.5rem);
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 1rem;
  color: var(--global-text-color);
  background: transparent;
  font-family: inherit;
  font-size: 0.9375rem;
  line-height: 1.4;
  pointer-events: none;
  transition: background-color 0.3s 0.2s;
}

.ball__settings--open {
  background: var(--global-bg-color);
  pointer-events: auto;
  transition-delay: 0s;
}

.ball__settings-trigger {
  position: fixed;
  z-index: 85;
  inset-block-end: var(--ball-gutter);
  inset-inline-end: var(--ball-gutter);
  display: grid;
  place-items: center;
  width: 1.75rem;
  height: 1.75rem;
  padding: 0;
  border: 1px solid var(--global-divider-color);
  color: var(--global-text-color);
  background: linear-gradient(var(--global-bg-color) 50%, var(--ball-accent) 50%) 0 0 / 100% 200%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateX(2rem) rotateY(-5deg);
  transition:
    opacity 0.2s,
    transform 0.4s cubic-bezier(0.7, 0, 0.7, 0.3) 0.1s,
    visibility 0.5s,
    background-position 0.3s;
}

.ball__settings-trigger--visible {
  opacity: 1;
  visibility: visible;
  transform: none;
  transition:
    opacity 0.475s 50ms,
    transform 0.6s cubic-bezier(0.3, 0.7, 0.2, 1.25) 50ms,
    visibility 0s,
    background-position 0.3s;
}

.ball__settings-trigger::before {
  content: "";
  width: 0.875rem;
  height: 0.875rem;
  border-radius: 50%;
  background: var(--ball-accent);
  transition: background-color 0.3s;
}

.ball__settings-trigger:hover {
  border-color: var(--ball-accent);
  background-position: 0 100%;
}

.ball__settings-trigger:hover::before {
  background: var(--global-bg-color);
}

.ball__settings-trigger[aria-expanded="true"] {
  border-color: var(--ball-accent);
}

.ball__settings-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.375rem;
  margin: 0;
  min-width: 0;
  perspective: 400px;
  visibility: hidden;
  transition: visibility 0.7s;
}

.ball__settings-row > :not([type="hidden"]) {
  opacity: 0;
  transform-origin: 150%;
  transform: translateX(2rem) rotateY(-5deg);
  transition:
    opacity 0.2s,
    transform 0.4s cubic-bezier(0.7, 0, 0.7, 0.3);
  transition-delay: calc(var(--rank, 0) * 30ms), calc(0.1s + var(--rank, 0) * 30ms);
}

.ball__settings--open .ball__settings-row {
  visibility: visible;
}

.ball__settings--open .ball__settings-row > :not([type="hidden"]) {
  opacity: 1;
  transform: none;
  transition:
    opacity 0.475s,
    transform 0.6s cubic-bezier(0.3, 0.7, 0.2, 1.25);
  transition-delay: calc(50ms + var(--order, 0) * 35ms), calc(50ms + var(--order, 0) * 30ms);
}

.ball__settings-toggle {
  cursor: pointer;
}

.ball__settings-toggle input {
  appearance: none;
  position: relative;
  width: 1.75rem;
  height: 0.875rem;
  margin: 0;
  border: 1px solid currentColor;
  border-radius: 0;
  background: transparent;
  color: inherit;
  cursor: pointer;
}

.ball__settings-toggle input::before {
  content: "";
  position: absolute;
  inset: 2px auto 2px 2px;
  aspect-ratio: 1;
  border: 1px solid currentColor;
  transition: translate 0.25s cubic-bezier(0.3, 0.7, 0, 1);
}

.ball__settings-toggle input:checked {
  border-color: var(--ball-accent);
  background: var(--ball-accent);
}

.ball__settings-toggle input:checked::before {
  translate: 0.875rem;
  border-color: var(--global-bg-color);
  background: var(--global-bg-color);
}

.ball__settings-stamp {
  position: relative;
  width: 1.75rem;
  height: 1.75rem;
  padding: 0;
  border: 1px solid currentColor;
  color: inherit;
  background: transparent;
  cursor: pointer;
}

.ball__settings-stamp::before {
  content: "";
  position: absolute;
  inset: 2px;
  background: currentColor;
  mask: var(--stamp) center / contain no-repeat;
  -webkit-mask: var(--stamp) center / contain no-repeat;
}

.ball__settings-stamp--hole::before {
  inset: 0.375rem;
  border: 1px solid currentColor;
  border-radius: 50%;
  background: transparent;
  mask: none;
  -webkit-mask: none;
}

.ball__settings-range {
  flex: 1;
  min-width: 0;
  width: 100%;
  height: 1.3rem;
  margin: 0;
  accent-color: var(--ball-accent);
  cursor: pointer;
}

.ball__settings-swatches {
  display: flex;
  gap: 0.65rem;
  margin-inline-start: auto;
  padding: 3px;
}

.ball__settings-swatch {
  position: relative;
  width: 0.875rem;
  height: 0.875rem;
  margin: 0;
  border-radius: 50%;
  background: var(--swatch);
  box-shadow: inset 0 0 0 1px #00000014;
  cursor: pointer;
}

.ball__settings-swatch input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}

.ball__settings-swatch:has(:checked) {
  outline: 1px solid var(--global-text-color);
  outline-offset: 2px;
}

.ball__settings-swatch:has(:focus-visible) {
  outline: 2px solid var(--ball-accent);
  outline-offset: 2px;
}

.ball__settings-swatch--theme {
  --swatch: var(--ball-accent);
}

.ball__settings-swatch--cycle {
  --swatch: conic-gradient(in oklch longer hue, oklch(70% 0.2 30), oklch(70% 0.2 30));
}

.ball__settings-swatch--poline {
  --swatch: var(--ball-poline);
}

.ball__settings-swatch--gradient {
  --swatch: var(--ball-gradient);
}

.ball__settings-swatch--custom {
  --swatch: var(--ball-custom, #3ddc84);
}

.ball__settings-picker {
  width: 1.75rem;
  height: 1.3rem;
  padding: 0;
  border: 1px solid var(--global-divider-color);
  background: transparent;
  cursor: pointer;
}

.ball__settings[hidden],
.ball__settings-trigger[hidden],
.ball__shadow[hidden] {
  display: none;
}

body.scroll-ball-active #back-to-top {
  right: calc(var(--ball-gutter) + 3rem);
}

/* Room for the ball's lane between the panel edge and the cards, on top of .post's left padding (see _blog.scss).
   groove() gives up when the list starts less than one --ball-size in, so as the padding thins the margin grows.
   Below 48.75em the ball leaves the lane anyway. */
body.scroll-ball-page .post-list {
  margin-inline-start: 2.5rem;
}

/* .post's padding is down to 2rem here, so the margin tracks the ball to keep the cards 1rem clear of it. */
@media (max-width: 992px) {
  body.scroll-ball-page .post-list {
    margin-inline-start: calc(var(--ball-size) - 1rem);
  }
}

@media (max-width: 768px) {
  body.scroll-ball-page .post-list {
    margin-inline-start: 0.625rem;
  }
}

@media (max-width: 576px) {
  body.scroll-ball-page .post-list {
    margin-inline-start: 0.5rem;
  }
}

@media (max-width: 68.75em) {
  body.scroll-ball-page {
    --ball-gutter: 1.875rem;
  }
}

@media (max-width: 48.75em) {
  body.scroll-ball-page {
    --ball-gutter: 1.5625rem;
  }

  body.scroll-ball-active .container[role="main"] {
    padding-inline-start: 4rem;
  }
}

@media (max-width: 33.75em) {
  body.scroll-ball-page {
    --ball-gutter: 1.375rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  body.scroll-ball-page .runout {
    display: none;
  }

  .ball__dock,
  .ball__settings,
  .ball__settings-trigger,
  .ball__settings-trigger::before,
  .ball__settings-row,
  .ball__settings-row > *,
  .ball__settings-toggle input::before {
    transition: none;
  }
}