/* ============================================================
   OPERATION DIGITAL ALCHEMY — site stylesheet
   Field-manual system: brass on near-black, bone-paper panels.
   ============================================================ */

:root{
  --ink:#0C0C0E;
  --ink-2:#141418;
  --brass:#B8862F;
  --brass-lit:#D9A441;
  --paper:#E8E4DA;
  --paper-2:#DCD6C8;
  --rule:#2A2A30;
  --muted:#8A8A93;
  --text:#DEDCD7;
  --white:#F2EFE9;

  --display:'Big Shoulders Display','Arial Narrow',sans-serif;
  --body:'IBM Plex Sans',system-ui,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,monospace;

  --pad:clamp(20px,5vw,72px);
  --maxw:1100px;
}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;background:var(--ink);color:var(--text);
  font-family:var(--body);font-size:16px;line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
.wrap{max-width:var(--maxw);margin:0 auto;padding-left:var(--pad);padding-right:var(--pad)}
img{max-width:100%;height:auto}

a{color:var(--brass-lit);text-decoration:none;border-bottom:1px solid rgba(217,164,65,.35)}
a:hover{border-bottom-color:var(--brass-lit)}
:focus-visible{outline:2px solid var(--brass-lit);outline-offset:3px}

/* ---------- nav ---------- */
.nav{border-bottom:1px solid var(--rule);position:sticky;top:0;background:rgba(12,12,14,.94);backdrop-filter:blur(8px);z-index:20}
.nav .wrap{display:flex;justify-content:space-between;align-items:center;gap:20px;
  padding-top:16px;padding-bottom:16px;flex-wrap:wrap}
.nav-brand{
  font-family:var(--display);font-weight:800;text-transform:uppercase;
  font-size:17px;letter-spacing:.06em;color:var(--white);border:0;line-height:1;
}
.nav-brand:hover{color:var(--brass-lit);border:0}
.nav-links{display:flex;gap:22px;font-family:var(--mono);font-size:11px;
  letter-spacing:.16em;text-transform:uppercase}
.nav-links a{color:var(--muted);border:0;padding-bottom:2px;border-bottom:1px solid transparent}
.nav-links a:hover,.nav-links a[aria-current="page"]{color:var(--brass);border-bottom-color:var(--brass)}

/* ---------- shared type ---------- */
.eyebrow{font-family:var(--mono);font-size:11px;letter-spacing:.24em;
  text-transform:uppercase;color:var(--brass);margin:0 0 22px}
.page-title{
  font-family:var(--display);font-weight:800;text-transform:uppercase;
  font-size:clamp(44px,9vw,92px);line-height:.88;margin:0;color:var(--white);letter-spacing:.005em;
}
.lede{margin-top:28px;max-width:62ch;font-size:clamp(17px,2.2vw,20px);line-height:1.55;color:var(--white)}

.page-head{padding-top:clamp(44px,8vw,88px);padding-bottom:clamp(36px,6vw,68px)}

section.band{border-top:1px solid var(--rule)}
.sec-head{display:flex;gap:18px;align-items:baseline;padding-top:clamp(40px,6vw,64px);flex-wrap:wrap}
.sec-num{font-family:var(--mono);font-size:12px;color:var(--brass);letter-spacing:.1em;white-space:nowrap}
.sec-title{font-family:var(--display);font-weight:700;text-transform:uppercase;
  font-size:clamp(28px,5vw,46px);line-height:1;margin:0;letter-spacing:.01em;color:var(--white)}

.para{display:grid;grid-template-columns:64px 1fr;gap:18px;margin-top:28px;max-width:76ch}
.para .n{font-family:var(--mono);font-size:12px;color:var(--brass);padding-top:5px}
.para p{margin:0}
.para p + p{margin-top:14px}
.pad-btm{padding-bottom:clamp(40px,6vw,72px)}

/* ---------- hero (home) ---------- */
.hero{padding-top:clamp(56px,11vw,132px);padding-bottom:clamp(48px,9vw,104px)}
.hero h1{
  font-family:var(--display);font-weight:800;text-transform:uppercase;
  font-size:clamp(52px,12vw,140px);line-height:.84;margin:0;color:var(--white);letter-spacing:-.002em;
}
.hero h1 span{display:block}
.hero h1 .lit{color:var(--brass)}
.tagline{
  margin-top:32px;max-width:52ch;font-size:clamp(18px,2.6vw,24px);line-height:1.45;color:var(--white);
  border-left:2px solid var(--brass);padding-left:24px;
}
.hero-meta{font-family:var(--mono);font-size:11px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--muted);margin-top:40px}

/* ---------- card grid ---------- */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:0;
  border:1px solid var(--rule);margin-top:clamp(36px,6vw,56px);margin-bottom:clamp(44px,7vw,80px)}
.card{border-right:1px solid var(--rule);padding:28px 24px 32px;display:block;
  border-bottom:0;color:var(--text);transition:background .18s ease}
.card:last-child{border-right:0}
.card:hover{background:var(--ink-2);border-bottom:0}
.card .k{font-family:var(--mono);font-size:10px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--brass);display:block;margin-bottom:14px}
.card h3{font-family:var(--display);font-weight:700;text-transform:uppercase;font-size:26px;
  line-height:1.02;margin:0 0 12px;color:var(--white)}
.card p{margin:0;font-size:14.5px;line-height:1.55;color:var(--muted)}

/* ---------- bone-paper panel + eight boxes ---------- */
.form-panel{background:var(--paper);color:#1A1814;
  padding-top:clamp(28px,5vw,48px);padding-bottom:clamp(28px,5vw,48px)}
.form-inner{max-width:var(--maxw);margin:0 auto;padding-left:var(--pad);padding-right:var(--pad)}
.form-head{display:flex;justify-content:space-between;align-items:flex-end;gap:16px;flex-wrap:wrap;
  border-bottom:2px solid #1A1814;padding-bottom:10px}
.form-head h3{font-family:var(--display);font-weight:700;text-transform:uppercase;
  font-size:clamp(20px,3.4vw,30px);margin:0;line-height:1;letter-spacing:.02em}
.form-head span{font-family:var(--mono);font-size:10px;letter-spacing:.16em;
  text-transform:uppercase;color:#6B6455}

.engine{margin-top:30px}
.engine-label{font-family:var(--mono);font-size:10px;letter-spacing:.2em;text-transform:uppercase;
  color:#6B6455;display:flex;align-items:center;gap:12px;margin-bottom:12px}
.engine-label::after{content:"";flex:1;height:1px;background:#B9B1A0}

.boxes{display:grid;grid-template-columns:repeat(4,1fr);border:1px solid #1A1814}
.box{border-right:1px solid #1A1814;padding:18px 16px 20px;min-height:172px;
  background:var(--paper);transition:background .18s ease}
.box:last-child{border-right:0}
.box:hover{background:var(--paper-2)}
.box .letter{font-family:var(--display);font-weight:800;font-size:44px;line-height:.9;
  color:var(--brass);display:block;margin-bottom:8px}
.box .name{font-family:var(--mono);font-size:11px;font-weight:600;letter-spacing:.12em;
  text-transform:uppercase;display:block;margin-bottom:10px}
.box .does{font-size:13.5px;line-height:1.5;color:#3A362E;margin:0}
.box{opacity:0;transform:translateY(10px)}
.box.in{opacity:1;transform:none;transition:opacity .5s ease,transform .5s ease,background .18s ease}

/* ---------- annotated example ---------- */
.example{margin-top:30px;background:var(--ink-2);border:1px solid var(--rule);
  padding:clamp(18px,3vw,28px);font-family:var(--mono);font-size:14px;line-height:1.95}
.example .tag{color:var(--brass);font-size:10px;letter-spacing:.14em;
  vertical-align:super;margin-left:4px;user-select:none}

/* ---------- definition list block ---------- */
.cite-block{margin-top:30px;border:1px solid var(--rule);
  padding:clamp(18px,3vw,28px);background:var(--ink-2)}
.cite-block dt{font-family:var(--mono);font-size:10px;letter-spacing:.18em;
  text-transform:uppercase;color:var(--brass);margin-bottom:6px}
.cite-block dd{margin:0 0 22px;font-size:15px}
.cite-block dd:last-child{margin-bottom:0}
.cite-block code{font-family:var(--mono);font-size:13.5px;color:var(--white);word-break:break-word}

/* ---------- book list ---------- */
.books{border-top:1px solid var(--rule);margin-top:clamp(32px,5vw,52px)}
.book{border-bottom:1px solid var(--rule);padding:30px 0;
  display:grid;grid-template-columns:56px 1fr;gap:20px;align-items:start}
.book .idx{font-family:var(--mono);font-size:12px;color:var(--brass);padding-top:6px;letter-spacing:.08em}
.book h3{font-family:var(--display);font-weight:700;text-transform:uppercase;
  font-size:clamp(24px,4vw,34px);line-height:1.02;margin:0;color:var(--white);letter-spacing:.01em}
.book .sub{font-family:var(--mono);font-size:11.5px;letter-spacing:.06em;color:var(--brass);
  margin:10px 0 0;text-transform:uppercase;line-height:1.6}
.book p.desc{margin:14px 0 0;max-width:66ch;color:var(--text)}
.book .status{font-family:var(--mono);font-size:10px;letter-spacing:.18em;text-transform:uppercase;
  color:var(--muted);margin-top:12px;display:block}

/* ---------- footer ---------- */
footer{border-top:1px solid var(--rule);margin-top:clamp(48px,7vw,88px)}
footer .wrap{padding-top:36px;padding-bottom:56px}
.byline{font-family:var(--display);text-transform:uppercase;font-weight:700;
  font-size:clamp(18px,2.8vw,24px);color:var(--white);margin:0 0 6px;letter-spacing:.02em}
.byline-sub{font-family:var(--mono);font-size:11px;letter-spacing:.12em;
  text-transform:uppercase;color:var(--muted);margin:0 0 28px}
.notice{font-family:var(--mono);font-size:11px;line-height:1.9;letter-spacing:.04em;
  color:var(--muted);max-width:70ch}
.notice strong{color:var(--brass);font-weight:500}

/* ---------- responsive ---------- */
@media (max-width:900px){
  .cards{grid-template-columns:1fr}
  .card{border-right:0;border-bottom:1px solid var(--rule)}
  .card:last-child{border-bottom:0}
}
@media (max-width:860px){
  .boxes{grid-template-columns:repeat(2,1fr)}
  .box{border-bottom:1px solid #1A1814;min-height:0}
  .box:nth-child(2n){border-right:0}
  .box:nth-child(n+3){border-bottom:0}
}
@media (max-width:520px){
  .boxes{grid-template-columns:1fr}
  .box{border-right:0;border-bottom:1px solid #1A1814}
  .box:nth-child(n+3){border-bottom:1px solid #1A1814}
  .box:nth-child(4){border-bottom:0}
  .para{grid-template-columns:1fr;gap:6px}
  .book{grid-template-columns:1fr;gap:10px}
  .book .idx{padding-top:0}
  .sec-head{flex-direction:column;gap:8px}
  .nav-links{gap:16px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .box{opacity:1;transform:none;transition:none}
}