/**
 * Case study — editorial narrative template
 */

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ——— Reading progress ——— */

.cs-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  height: 2px;
  background: transparent;
  pointer-events: none;
}

.cs-progress__bar {
  height: 100%;
  background: var(--color-accent);
  transform-origin: left center;
  transform: scaleX(0);
  transition: transform 80ms linear;
}

/* ——— Page shell ——— */

.cs-page {
  padding-top: var(--nav-height);
}

.cs-page__layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--page-margin);
}

.cs-main {
  width: 100%;
  min-width: 0;
  padding-block: var(--space-6) var(--space-7);
}

.cs-article {
  display: flex;
  flex-direction: column;
  gap: var(--space-7);
}

/* ——— Navigation tweaks ——— */

.cs-nav__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.cs-nav__brand {
  text-decoration: none;
}

.cs-nav__contact {
  margin-left: auto;
}

/* ——— Table of contents ——— */

.cs-toc {
  display: none;
}

@media only screen and (min-width: 1100px) {
  .cs-page__layout {
    grid-template-columns: 11rem minmax(0, 1fr);
    gap: var(--space-5);
    align-items: start;
  }

  .cs-toc {
    display: block;
    position: sticky;
    top: calc(var(--nav-height) + var(--space-3));
    padding-top: var(--space-6);
  }

  .cs-toc__label {
    margin: 0 0 var(--space-2);
    color: var(--color-accent-text);
    font-family: var(--font-sans);
    font-size: var(--text-micro);
    font-weight: var(--weight-medium);
    letter-spacing: var(--tracking-wide);
    text-transform: uppercase;
  }

  .cs-toc__list {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
  }

  .cs-toc__link {
    display: block;
    padding-block: 0.35rem;
    color: var(--color-text-tertiary);
    font-family: var(--font-sans);
    font-size: var(--text-small);
    line-height: var(--leading-snug);
    text-decoration: none;
    border-left: 2px solid transparent;
    padding-left: var(--space-2);
    transition: var(--transition-color), border-color var(--duration-fast) var(--ease-default);
  }

  .cs-toc__link:hover,
  .cs-toc__link.is-active {
    color: var(--color-text-primary);
  }

  .cs-toc__link.is-active {
    border-left-color: var(--color-link);
  }
}

/* ——— Scroll reveal ——— */

.cs-reveal {
  opacity: 1;
  transform: translateY(0);
}

html.js .cs-reveal {
  opacity: 0;
  transform: translateY(var(--hero-enter-distance));
  transition:
    opacity var(--duration-slow) var(--ease-out),
    transform var(--duration-slow) var(--ease-out);
}

html.js .cs-reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html.js .cs-reveal,
  html.js .cs-reveal.is-visible {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .cs-progress__bar {
    transition: none;
  }
}

/* ——— Shared typography ——— */

.cs-label {
  margin: 0 0 var(--space-3);
  color: var(--color-accent-text);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.cs-body {
  margin: 0;
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  font-size: var(--text-body);
  line-height: var(--leading-relaxed);
}

.cs-body + .cs-body {
  margin-top: var(--space-3);
}

.cs-section__heading {
  margin: 0 0 var(--space-3);
  max-width: 18em;
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h2);
  font-weight: var(--weight-medium);
  line-height: var(--leading-snug);
  letter-spacing: var(--tracking-tight);
}

.cs-subheading {
  margin: 0 0 var(--space-2);
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h3);
  font-weight: var(--weight-medium);
  line-height: var(--leading-snug);
}

.cs-section__intro {
  max-width: var(--container-text);
  margin-bottom: var(--space-4);
}

.cs-prose {
  max-width: var(--container-text);
}

.cs-insight {
  margin: var(--space-4) 0 0;
  max-width: 20em;
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-impact);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
}

.cs-quote {
  margin: 0 0 var(--space-4);
  padding: 0 0 0 var(--space-3);
  max-width: var(--container-text);
  border: none;
  border-left: var(--border-width-strong) solid var(--color-accent-peach);
}

.cs-quote p {
  margin: 0;
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h2);
  font-style: italic;
  line-height: var(--leading-snug);
  letter-spacing: var(--tracking-tight);
}

.cs-quote cite {
  display: block;
  margin-top: var(--space-2);
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
  font-style: normal;
}

.cs-quote--inline {
  margin-block: var(--space-4);
}

/* ——— Solution (early in narrative) ——— */

.cs-section--solution {
  gap: var(--space-4);
}

.cs-highlights {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  margin-top: var(--space-2);
}

.cs-highlights-label {
  margin: 0 0 var(--space-2);
  color: var(--color-accent-text);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

/* ——— Hero ——— */

.cs-hero {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.cs-back-link {
  display: inline-block;
  margin-bottom: var(--space-2);
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-decoration: none;
  transition: var(--transition-color);
}

.cs-back-link:hover {
  color: var(--color-link);
}

.cs-hero__impact {
  margin: 0;
  max-width: 11em;
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-hero);
  font-weight: var(--weight-regular);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
}

.cs-hero__title {
  margin: 0;
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-h3);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
}

.cs-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3) var(--space-4);
  margin: var(--space-1) 0 0;
  padding: 0;
}

.cs-hero__meta-item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.cs-hero__meta dt {
  color: var(--color-accent-text);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.cs-hero__meta dd {
  margin: 0;
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
}

.cs-hero__media-wrap {
  margin-top: var(--space-3);
}

.cs-hero__media {
  margin: 0;
  overflow: hidden;
  border-radius: var(--image-radius);
}

.cs-hero__image {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  object-position: center;
  border-radius: var(--image-radius);
  filter: saturate(var(--image-saturate));
  transition: transform var(--duration-normal) var(--ease-out);
}

.cs-hero__media:hover .cs-hero__image {
  transform: scale(1.01);
}

/* ——— Sections ——— */

.cs-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.cs-section--text {
  max-width: var(--container-text);
}

.cs-section--afterword {
  padding-top: var(--space-2);
}

.cs-stack {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.cs-stack--spacious {
  gap: var(--space-6);
}

/* ——— Figures ——— */

.cs-figure,
.cs-figure__frame {
  margin: 0;
  background-color: transparent;
}

.cs-figure__image,
.cs-row__image {
  display: block;
  width: 100%;
  border-radius: var(--image-radius);
  filter: saturate(var(--image-saturate));
  transition: transform var(--duration-normal) var(--ease-out);
}

.cs-figure--full .cs-figure__image {
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: center;
}

.cs-figure--half .cs-figure__image {
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.cs-figure__caption {
  margin: var(--space-2) 0 0;
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
  line-height: var(--leading-normal);
}

.cs-figure-group {
  display: grid;
  gap: var(--space-4);
}

.cs-figure-group--pair {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.cs-figure-group--trio {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

@media only screen and (max-width: 899px) {
  .cs-figure-group--trio {
    grid-template-columns: 1fr;
  }
}

/* ——— Editorial rows ——— */

.cs-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-5);
  align-items: center;
}

.cs-row--reverse {
  direction: rtl;
}

.cs-row--reverse .cs-row__content,
.cs-row--reverse .cs-row__media {
  direction: ltr;
}

.cs-row__heading {
  margin: 0 0 var(--space-2);
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h2);
  font-weight: var(--weight-medium);
  line-height: var(--leading-snug);
}

.cs-row__media {
  margin: 0;
  overflow: hidden;
  border-radius: var(--image-radius);
  background-color: transparent;
}

.cs-row__image {
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.cs-row:hover .cs-row__image,
.cs-figure:hover .cs-figure__image {
  transform: scale(1.02);
}

/* ——— Video ——— */

.cs-video-wrap {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.cs-video {
  display: block;
  width: 100%;
  border-radius: var(--image-radius);
  filter: saturate(var(--image-saturate));
}

/* ——— Embedded media (YouTube, etc.) ——— */

.cs-embed {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-width: min(100%, 32rem);
}

.cs-embed--feature {
  margin-block: var(--space-2) var(--space-4);
}

@media only screen and (min-width: 900px) {
  .cs-embed--feature {
    margin-left: auto;
    max-width: 28rem;
  }
}

.cs-embed__frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--image-radius);
  background-color: var(--color-text-primary);
}

.cs-embed__frame iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* ——— Scannable insight list ——— */

.cs-insight-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  max-width: var(--container-text);
}

.cs-insight-list__item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding-left: var(--space-3);
  border-left: 2px solid var(--color-border-strong);
}

.cs-insight-list__title {
  margin: 0;
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h3);
  font-weight: var(--weight-medium);
  line-height: var(--leading-snug);
}

.cs-insight-list__item .cs-body {
  margin: 0;
}

/* ——— Process steps ——— */

.cs-steps {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.cs-step__label {
  margin: 0 0 var(--space-2);
  color: var(--color-accent-text);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.cs-step__heading {
  margin: 0 0 var(--space-2);
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h2);
  font-weight: var(--weight-medium);
  line-height: var(--leading-snug);
}

.cs-step__changes {
  margin: var(--space-2) 0 0;
  padding-left: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.cs-step__changes .cs-body {
  margin: 0;
}

.cs-figure-stack {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
  margin-top: var(--space-4);
}

.cs-figure-stack .cs-step__label {
  margin-bottom: calc(-1 * var(--space-1));
}

/* ——— Reflection ——— */

.cs-reflection-block + .cs-reflection-block {
  margin-top: var(--space-4);
}

.cs-reflection-list {
  margin: 0;
  padding-left: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.cs-reflection-list .cs-body {
  color: var(--color-text-secondary);
}

.cs-reflection-growth {
  margin-top: var(--space-4);
  max-width: var(--container-text);
  color: var(--color-text-primary);
}

.cs-credits {
  margin: var(--space-5) 0 0;
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  line-height: var(--leading-normal);
}

/* ——— Next project ——— */

.cs-next {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
  padding-top: var(--space-5);
  border-top: var(--border-width) solid var(--color-border);
}

.cs-next__link {
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-decoration: none;
  transition: var(--transition-color);
}

.cs-next__link:hover {
  color: var(--color-link);
}

.cs-next__project {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  max-width: 24em;
  color: inherit;
  text-decoration: none;
  transition: var(--transition-color);
}

.cs-next__project:hover {
  color: inherit;
}

.cs-next__project:hover .cs-next__impact {
  color: var(--color-link);
}

.cs-next__eyebrow {
  color: var(--color-accent-text);
  font-family: var(--font-sans);
  font-size: var(--text-micro);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.cs-next__impact {
  color: var(--color-text-primary);
  font-family: var(--font-serif);
  font-size: var(--text-h2);
  line-height: var(--leading-snug);
  transition: var(--transition-color);
}

.cs-next__title {
  color: var(--color-text-tertiary);
  font-family: var(--font-sans);
  font-size: var(--text-small);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
}

/* ——— Footer ——— */

.cs-footer {
  margin-top: 0;
}

/* ——— Responsive ——— */

@media only screen and (max-width: 900px) {
  .cs-main {
    padding-block: var(--space-5) var(--space-6);
  }

  .cs-article {
    gap: var(--space-6);
  }

  .cs-row,
  .cs-row--reverse {
    grid-template-columns: 1fr;
    direction: ltr;
    gap: var(--space-4);
  }

  .cs-figure-group--pair {
    grid-template-columns: 1fr;
  }

  .cs-hero__impact {
    max-width: none;
  }
}

@media only screen and (max-width: 600px) {
  .cs-main {
    padding-block: var(--space-4) var(--space-5);
  }

  .cs-article {
    gap: var(--space-5);
  }

  .cs-quote p {
    font-size: var(--text-h3);
  }
}

@media (prefers-reduced-motion: reduce) {
  .cs-hero__image,
  .cs-row__image,
  .cs-figure__image {
    transition: none;
  }

  .cs-hero__media:hover .cs-hero__image,
  .cs-row:hover .cs-row__image,
  .cs-figure:hover .cs-figure__image {
    transform: none;
  }
}