/* ============================================================
   HALDEN case study (work-halden.html only)

   Loaded after base.css and case-study.css. The presentation is
   Locus: Locus surfaces, type, borders and grid. Halden's own
   colours and its datum line appear only inside the work itself,
   the boards, renders and screens. Nothing in this file uses them.

   Grid: chapter heads split 4fr / 8fr with a 40px gap (case-study
   .chapter-head). Full-width boards and their captions start on the
   content edge; card rows span the container.
   ============================================================ */

/* boards */
.hd-frame{margin:0;}
.hd-frame img{display:block;width:100%;height:auto;border-radius:var(--radius-md);border:1px solid var(--border);}
.hd-hero img{border-radius:var(--radius-lg);}
.hd-gap{margin-top:var(--space-6);}
.hd-cap{margin-top:16px;font-size:15px;line-height:1.55;color:var(--ink-faint);max-width:620px;}
.hd-cap strong{color:var(--ink);font-weight:600;}

.hd-two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:var(--space-5) clamp(20px,2.6vw,32px);margin-top:var(--space-6);}
@media (max-width:860px){.hd-two{grid-template-columns:1fr;}}

/* cards: Locus neutral surface, hairline border, dark type */
.hd-cards{list-style:none;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:clamp(10px,1.4vw,16px);}
.hd-card{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);padding:clamp(22px,2.4vw,30px);display:flex;flex-direction:column;}
.case-chapter.is-alt .hd-card{background:var(--bg);}
.case-chapter:not(.is-alt) .hd-card{background:var(--bg-alt);}
.hd-card-n{font-size:12px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-faint);margin-bottom:clamp(32px,4vw,56px);}
.hd-card h3{font-size:clamp(19px,1.6vw,22px);line-height:1.2;letter-spacing:-0.02em;color:var(--ink);margin-bottom:10px;}
.hd-card p{font-size:15px;line-height:1.5;color:var(--ink-soft);}
/* the four applications of the rule sit between the head and the board */
.hd-rules{margin-bottom:var(--space-6);}
.hd-rules .hd-card-n{margin-bottom:28px;}
.hd-rules .hd-card p{font-size:16px;color:var(--ink);}
@media (max-width:1000px){.hd-cards{grid-template-columns:repeat(2,minmax(0,1fr));}}
@media (max-width:560px){.hd-cards{grid-template-columns:1fr;}.hd-card-n{margin-bottom:24px;}}