/* =====================================================================
   case.css — dedicated case-study pages (projects/<slug>/)
   Inherits tokens/type/cursor from base.css; --ca is the project accent
   set by case.js from js/data.js. Editorial, readable, recruiter-first.
   ===================================================================== */

:root { --ca: var(--acid); }

/* ------------------------------ header ------------------------------- */
.csnav { position: fixed; inset: 0 0 auto 0; z-index: 800; mix-blend-mode: difference; }
.csnav__inner { display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding: 1.1rem var(--gut); }
.csnav__mark { font-family: var(--f-display); font-weight: 800; font-size: 1.05rem;
  color: #fff; flex-shrink: 0; }
.csnav__crumb { font-family: var(--f-mono); font-size: 0.6rem; letter-spacing: 0.22em;
  text-transform: uppercase; color: #fff; opacity: 0.75; overflow: hidden;
  text-overflow: ellipsis; white-space: nowrap; min-width: 0; }
.csnav__crumb a { border-bottom: 1px solid rgba(255,255,255,0.35); padding-bottom: 1px; }
.csnav__side { display: flex; align-items: center; gap: 1.1rem; flex-shrink: 0;
  font-family: var(--f-mono); font-size: 0.62rem; letter-spacing: 0.2em;
  text-transform: uppercase; color: #fff; }
.csnav__side a { padding: 0.4rem 0.2rem; }
.csnav__side a:hover { color: var(--ca); }

/* ------------------------------ hero --------------------------------- */
.cshero { padding: clamp(7rem, 14vh, 9.5rem) 0 clamp(2.2rem, 5vw, 3.6rem);
  border-bottom: 1px solid var(--line); position: relative; overflow: hidden; }
.cshero::before { content: ""; position: absolute; inset: 0; pointer-events: none;
  background: radial-gradient(58% 44% at 82% 8%,
    color-mix(in srgb, var(--ca) 10%, transparent), transparent 70%); }
.cshero .wrap { position: relative; }
.cshero__top { display: flex; align-items: baseline; justify-content: space-between;
  gap: 1.2rem; flex-wrap: wrap; margin-bottom: 1.2rem; }
.cshero__idx { font-family: var(--f-mono); font-size: 0.66rem; letter-spacing: 0.24em;
  text-transform: uppercase; color: var(--ca); }
.cshero__pn { display: flex; gap: 1.4rem; font-family: var(--f-mono); font-size: 0.62rem;
  letter-spacing: 0.2em; text-transform: uppercase; }
.cshero__pn a { color: var(--paper-dim); padding: 0.3rem 0; }
.cshero__pn a:hover { color: var(--ca); }
.cshero__cat { font-family: var(--f-mono); font-size: 0.64rem; letter-spacing: 0.24em;
  text-transform: uppercase; color: var(--paper-dim); }
.cshero__title { margin-top: 0.7rem; font-family: var(--f-display); font-weight: 800;
  letter-spacing: -0.025em; line-height: 0.95; text-transform: uppercase;
  font-size: clamp(2.3rem, 6.4vw, 5.6rem); max-width: 16ch; }
.cshero__title em { font-style: normal; color: var(--ca); }
.cshero__sum { margin-top: 1.3rem; max-width: 52ch; color: var(--paper-dim);
  font-size: clamp(1rem, 1.4vw, 1.15rem); }
.cshero__meta { margin-top: 1.6rem; display: flex; flex-wrap: wrap; gap: 0.6rem 2rem;
  font-family: var(--f-mono); font-size: 0.66rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--paper-ghost); }
.cshero__meta b { color: var(--paper-dim); font-weight: 400; }
/* cover — conceptual system artwork. TODO: swap for coverImage per project */
.cshero__cover { margin-top: clamp(1.8rem, 4vw, 2.8rem); height: clamp(180px, 30vw, 320px);
  border: 1px solid var(--line); position: relative; overflow: hidden;
  background:
    repeating-linear-gradient(90deg, color-mix(in srgb, var(--ca) 8%, transparent) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(0deg, color-mix(in srgb, var(--ca) 6%, transparent) 0 1px, transparent 1px 64px),
    linear-gradient(160deg, color-mix(in srgb, var(--ca) 7%, transparent), transparent 55%); }
.cshero__cover span { position: absolute; right: 1.4rem; bottom: 0.4rem;
  font-family: var(--f-display); font-weight: 800; line-height: 1;
  font-size: clamp(5rem, 14vw, 11rem); color: transparent;
  -webkit-text-stroke: 1px color-mix(in srgb, var(--ca) 45%, transparent);
  user-select: none; }
.cshero__cover i { position: absolute; left: 1.2rem; bottom: 1rem; font-style: normal;
  font-family: var(--f-mono); font-size: 0.58rem; letter-spacing: 0.22em;
  text-transform: uppercase; color: var(--paper-ghost); }

/* ------------------------------ layout ------------------------------- */
.cs { display: grid; grid-template-columns: 200px minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem); align-items: start; padding-block: clamp(2.6rem, 6vw, 4.5rem); }
.cs__rail { position: sticky; top: 6.2rem; }
.cs__rail-label { font-family: var(--f-mono); font-size: 0.58rem; letter-spacing: 0.26em;
  text-transform: uppercase; color: var(--paper-ghost); margin-bottom: 0.9rem; }
.cs__rail ol { display: flex; flex-direction: column; gap: 0.15rem; }
.cs__rail a { display: block; padding: 0.42rem 0 0.42rem 0.9rem; position: relative;
  font-family: var(--f-mono); font-size: 0.64rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--paper-ghost);
  border-left: 1px solid var(--line); transition: color 0.3s, border-color 0.3s; }
.cs__rail a:hover { color: var(--paper); }
.cs__rail a.is-active { color: var(--ca); border-left-color: var(--ca); }

.cs__main { min-width: 0; }
.cs__sec { padding-block: clamp(1.8rem, 4vw, 3rem); border-bottom: 1px solid var(--line-soft);
  scroll-margin-top: 5.5rem; }
.cs__sec:first-child { padding-top: 0; }
.cs__label { font-family: var(--f-mono); font-size: 0.6rem; letter-spacing: 0.26em;
  text-transform: uppercase; color: var(--ca); margin-bottom: 0.7rem; }
.cs__h { font-family: var(--f-display); font-weight: 700; letter-spacing: -0.015em;
  font-size: clamp(1.4rem, 2.8vw, 2.2rem); margin-bottom: 1.2rem; }
.cs__lead { font-family: var(--f-display); font-weight: 600; line-height: 1.3;
  font-size: clamp(1.05rem, 1.8vw, 1.35rem); max-width: 34ch; margin-bottom: 0.9rem; }
.cs__body { color: var(--paper-dim); max-width: 62ch; }

/* overview facts */
.cs__facts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0; border-top: 1px solid var(--line); margin-bottom: 1.4rem; }
.cs__facts div { padding: 0.9rem 1rem 1.05rem 0; border-bottom: 1px solid var(--line-soft); }
.cs__facts dt { font-family: var(--f-mono); font-size: 0.58rem; letter-spacing: 0.22em;
  text-transform: uppercase; color: var(--paper-ghost); margin-bottom: 0.35rem; }
.cs__facts dd { color: var(--paper); font-size: 0.94rem; }

/* flow diagram */
.cs__flow { margin-top: 1.6rem; border: 1px solid var(--line); padding: 1.2rem 1.2rem 1rem;
  background: color-mix(in srgb, var(--ca) 3%, transparent); }
.cs__flow-track { display: flex; flex-wrap: wrap; align-items: center; gap: 0.55rem 0.7rem; }
.cs__flow-node { font-family: var(--f-mono); font-size: 0.66rem; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--paper); padding: 0.5rem 0.8rem;
  border: 1px solid color-mix(in srgb, var(--ca) 50%, transparent); }
.cs__flow-arrow { color: var(--ca); font-family: var(--f-mono); }
.cs__flow-note { margin-top: 0.9rem; font-family: var(--f-mono); font-size: 0.58rem;
  letter-spacing: 0.18em; text-transform: uppercase; color: var(--paper-ghost); }

/* features */
.cs__feats { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem 2.4rem; }
.cs__feat { border-top: 1px solid var(--line); padding-top: 0.9rem; }
.cs__feat-no { font-family: var(--f-mono); font-size: 0.6rem; letter-spacing: 0.22em;
  color: var(--ca); }
.cs__feat h3 { font-family: var(--f-display); font-weight: 700; font-size: 1.02rem;
  margin: 0.35rem 0 0.3rem; }
.cs__feat p { color: var(--paper-dim); font-size: 0.9rem; }

/* contribution */
.cs__contrib { display: flex; flex-direction: column; max-width: 56ch; }
.cs__contrib li { padding: 0.75rem 0.2rem; border-bottom: 1px solid var(--line-soft);
  color: var(--paper-dim); position: relative; padding-left: 1.4rem; }
.cs__contrib li::before { content: "—"; position: absolute; left: 0; color: var(--ca); }

/* process timeline */
.cs__steps { position: relative; display: flex; flex-direction: column; gap: 0;
  max-width: 60ch; }
.cs__steps::before { content: ""; position: absolute; left: 15px; top: 10px; bottom: 10px;
  width: 1px; background: var(--line); }
.cs__step { position: relative; display: flex; gap: 1.3rem; padding: 0.9rem 0; }
.cs__step-no { position: relative; z-index: 1; flex-shrink: 0; width: 31px; height: 31px;
  display: grid; place-items: center; border-radius: 50%; background: var(--ink);
  border: 1px solid color-mix(in srgb, var(--ca) 55%, transparent);
  font-family: var(--f-mono); font-size: 0.66rem; color: var(--ca); }
.cs__step h3 { font-family: var(--f-display); font-weight: 700; font-size: 1rem;
  margin-bottom: 0.2rem; }
.cs__step p { color: var(--paper-dim); font-size: 0.9rem; }

/* gallery */
.cs__gallery { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.2rem; }
.cs__shot { min-width: 0; }
.cs__shot-btn { display: block; width: 100%; border: 1px solid var(--line); }
.cs__shot img { width: 100%; aspect-ratio: 16 / 10; object-fit: cover; }
.cs__shot figcaption { margin-top: 0.55rem; font-family: var(--f-mono); font-size: 0.58rem;
  letter-spacing: 0.18em; text-transform: uppercase; color: var(--paper-ghost); }
.cs__concept { position: relative; aspect-ratio: 16 / 10; border: 1px solid var(--line);
  background:
    repeating-linear-gradient(90deg, color-mix(in srgb, var(--ca) 7%, transparent) 0 1px, transparent 1px 42px),
    repeating-linear-gradient(0deg, color-mix(in srgb, var(--ca) 5%, transparent) 0 1px, transparent 1px 42px); }
.cs__concept span { position: absolute; right: 0.9rem; bottom: 0.2rem;
  font-family: var(--f-display); font-weight: 800; font-size: 3.4rem; line-height: 1;
  color: transparent; -webkit-text-stroke: 1px color-mix(in srgb, var(--ca) 45%, transparent); }
.cs__concept i { position: absolute; left: 0.9rem; bottom: 0.8rem; font-style: normal;
  font-family: var(--f-mono); font-size: 0.56rem; letter-spacing: 0.2em;
  text-transform: uppercase; color: var(--paper-ghost); }

/* lightbox */
.cs__lb { position: fixed; inset: 0; z-index: 950; background: rgba(5,5,6,0.9);
  display: none; align-items: center; justify-content: center; padding: 3.6rem 4.5rem; }
.cs__lb.is-open { display: flex; }
.cs__lb figure { max-width: min(1100px, 100%); max-height: 100%; }
.cs__lb img { max-width: 100%; max-height: 76vh; object-fit: contain;
  border: 1px solid var(--line); }
.cs__lb figcaption { margin-top: 0.8rem; text-align: center; font-family: var(--f-mono);
  font-size: 0.62rem; letter-spacing: 0.2em; text-transform: uppercase;
  color: var(--paper-dim); }
.cs__lb-x { position: absolute; top: 1.2rem; right: 1.4rem; font-family: var(--f-mono);
  font-size: 0.62rem; letter-spacing: 0.2em; text-transform: uppercase;
  color: var(--paper); padding: 0.6rem; }
.cs__lb-prev, .cs__lb-next { position: absolute; top: 50%; transform: translateY(-50%);
  font-size: 1.4rem; color: var(--paper); padding: 1rem; }
.cs__lb-prev { left: 0.8rem; }
.cs__lb-next { right: 0.8rem; }
.cs__lb-x:hover, .cs__lb-prev:hover, .cs__lb-next:hover { color: var(--ca); }

/* challenges */
.cs__chal { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.4rem; border-top: 1px solid var(--line); padding: 1.1rem 0 1.3rem; }
.cs__chal h3 { font-family: var(--f-mono); font-weight: 400; font-size: 0.58rem;
  letter-spacing: 0.24em; text-transform: uppercase; color: var(--ca);
  margin-bottom: 0.45rem; }
.cs__chal p { color: var(--paper-dim); font-size: 0.9rem; }

/* learning */
.cs__lessons { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem 2rem; max-width: 60ch; }
.cs__lessons li { color: var(--paper-dim); font-size: 0.92rem; padding-left: 1.15rem;
  position: relative; }
.cs__lessons li::before { content: "+"; position: absolute; left: 0; color: var(--ca); }
.cs__reflect { margin-top: 1.6rem; font-family: var(--f-display); font-weight: 600;
  font-size: clamp(1.05rem, 1.8vw, 1.3rem); line-height: 1.35; max-width: 40ch;
  color: var(--paper); border-left: 2px solid var(--ca); padding-left: 1.1rem; }

/* links */
.cs__links { display: flex; flex-wrap: wrap; gap: 0.8rem; }
.cs__link { display: inline-flex; align-items: baseline; gap: 0.6rem;
  font-family: var(--f-mono); font-size: 0.64rem; letter-spacing: 0.18em;
  text-transform: uppercase; padding: 0.85rem 1.2rem; border: 1px solid
  color-mix(in srgb, var(--ca) 55%, transparent); color: var(--paper);
  transition: background 0.3s, color 0.3s; }
a.cs__link:hover { background: var(--ca); color: var(--ink); }
.cs__link.is-off { border-color: var(--line-soft); border-style: dashed;
  color: var(--paper-ghost); cursor: default; }
.cs__link.is-off i { font-style: normal; opacity: 0.75; letter-spacing: 0.1em; }

/* next project banner */
.cs__next { border-top: 1px solid var(--line); }
.cs__next-link { display: block; padding: clamp(2.4rem, 6vw, 4.5rem) var(--gut);
  position: relative; overflow: hidden; transition: color 0.35s var(--ease); }
.cs__next-link::before { content: ""; position: absolute; inset: 0; background: var(--ca);
  transform: scaleY(0); transform-origin: bottom; transition: transform 0.45s var(--ease); }
.cs__next-link > span { position: relative; display: block; }
.cs__next-title { font-family: var(--f-display); font-weight: 800; letter-spacing: -0.02em;
  text-transform: uppercase; line-height: 1; font-size: clamp(1.7rem, 5.4vw, 4.2rem);
  margin: 0.7rem 0 0.9rem; }
.cs__next-cta { font-family: var(--f-mono); font-size: 0.66rem; letter-spacing: 0.24em;
  text-transform: uppercase; color: var(--paper-dim); }
.cs__next-cta em { font-style: normal; display: inline-block;
  transition: transform 0.35s var(--ease); }
.cs__next-link:hover { color: var(--ink); }
.cs__next-link:hover::before { transform: scaleY(1); }
.cs__next-link:hover .cs__label,
.cs__next-link:hover .cs__next-cta { color: var(--ink); }
.cs__next-link:hover .cs__next-cta em { transform: translateX(8px); }
.cs__all { display: block; padding: 1.1rem var(--gut) 2.4rem; font-family: var(--f-mono);
  font-size: 0.6rem; letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--paper-ghost); }
.cs__all:hover { color: var(--ca); }

/* ----------------------------- responsive ---------------------------- */
@media (max-width: 1023px) {
  .cs { grid-template-columns: minmax(0, 1fr); }
  /* rail becomes a sticky horizontal chip bar, seated below the fixed nav */
  .cs__rail { position: sticky; top: 3.2rem; z-index: 500; background:
    color-mix(in srgb, var(--ink) 92%, transparent); backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px); margin-inline: calc(var(--gut) * -1);
    padding: 0.6rem var(--gut); border-block: 1px solid var(--line-soft); }
  .cs__rail-label { display: none; }
  .cs__rail ol { flex-direction: row; gap: 0.4rem; overflow-x: auto;
    -webkit-overflow-scrolling: touch; scrollbar-width: none; }
  .cs__rail ol::-webkit-scrollbar { display: none; }
  .cs__rail a { border-left: 0; border-bottom: 1px solid transparent;
    padding: 0.5rem 0.6rem; white-space: nowrap; }
  .cs__rail a.is-active { border-bottom-color: var(--ca); }
}
@media (max-width: 720px) {
  .cshero__pn { gap: 1rem; }
  .cs__facts, .cs__feats, .cs__gallery, .cs__lessons { grid-template-columns: minmax(0, 1fr); }
  .cs__chal { grid-template-columns: minmax(0, 1fr); gap: 0.9rem; }
  .cs__lb { padding: 3.4rem 0.8rem; }
  .cs__lb-prev, .cs__lb-next { top: auto; bottom: 0.6rem; transform: none; }
  .csnav__crumb { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .cs__next-link::before { transition: none; }
}