/* xem16.info — Gem assay certificate. Limestone paper, jade + ruby inks, guilloche security lines. */
:root{
  --paper:#F1EDE3;--sheet:#FAF8F2;--ink:#17201C;--text:#2C3631;--muted:#56625B;--line:#CBD1C6;--line-2:#E0E3D9;
  --jade:#0C5B45;--jade-d:#073A2C;--jade-t:#DCE8DF;--ruby:#A3173B;--ruby-d:#7A0F2B;--ruby-t:#F5DFE4;--brass:#9A7A3A;--brass-l:#D8BD82;
  --f-d:"Fraunces",Georgia,"Times New Roman",serif;--f-b:"Be Vietnam Pro",system-ui,-apple-system,"Segoe UI",sans-serif;--f-m:"IBM Plex Mono",ui-monospace,Consolas,monospace;
  --primary:var(--jade);--primary-contrast:#fff;--accent:var(--ruby);--surface:var(--sheet);--surface-2:var(--paper);--border:var(--line);
  --heading:var(--ink);--muted-c:var(--muted);--font-head:var(--f-d);--font-body:var(--f-b);
  --oct:polygon(30% 0,70% 0,100% 30%,100% 70%,70% 100%,30% 100%,0 70%,0 30%);
  --strip:44px;--hdr:68px;
  color-scheme:light;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-padding-top:calc(var(--hdr) + 20px)}
body{margin:0;background:var(--paper);color:var(--text);font:400 17px/1.72 var(--f-b);font-feature-settings:"kern";-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
img,svg{max-width:100%}
a{color:var(--jade);text-decoration-thickness:1px;text-underline-offset:.2em}
a:hover{color:var(--jade-d);text-decoration-thickness:2px}
:focus-visible{outline:3px solid var(--ruby);outline-offset:3px;border-radius:2px}
::selection{background:var(--jade);color:#fff}
.wrap{width:min(100% - 32px,1240px);margin-inline:auto}
.skip{position:absolute;left:16px;top:-120px;z-index:200;background:var(--ink);color:#fff;padding:12px 18px;font-weight:600;text-decoration:none}
.skip:focus{top:10px;color:#fff}
h1,h2,h3{color:var(--ink);font-family:var(--f-d);font-optical-sizing:auto;font-weight:600;letter-spacing:-.012em;text-wrap:balance}
h2,h3,[id]{scroll-margin-top:calc(var(--hdr) + 20px)}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:52px;padding:0 22px;border-radius:3px;border:1px solid transparent;font:600 16px/1.2 var(--f-b);text-decoration:none;text-align:center;cursor:pointer;transition:background-color .18s,color .18s,border-color .18s,transform .18s}
.btn .ar{width:18px;height:18px;flex:none;transition:transform .2s}
.btn:hover .ar{transform:translateX(3px)}
.btn-sm{min-height:44px;padding:0 16px;font-size:15px}
.btn-jade{background:var(--jade);color:#fff}
.btn-jade:hover{background:var(--jade-d);color:#fff}
.btn-line{border-color:var(--ink);color:var(--ink);background:transparent}
.btn-line:hover{background:var(--ink);color:var(--sheet)}
.btn-paper{background:var(--sheet);color:var(--jade-d)}
.btn-paper:hover{background:#fff;color:var(--jade-d)}

/* ---------- header ---------- */
.hd{position:sticky;top:calc(-1 * var(--strip));z-index:60;background:var(--sheet);border-bottom:1px solid var(--line)}
.strip{background:var(--ink);color:#C8D1CB;font:500 12px/1.2 var(--f-m);letter-spacing:.03em}
.strip-in{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:var(--strip)}
.serial{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
@media (max-width:639px){.serial .sx{display:none}}
.lsw{display:flex;flex:none}
.lsw a{display:inline-flex;align-items:center;gap:6px;min-height:44px;min-width:44px;padding:0 10px;color:#C8D1CB;text-decoration:none;border-bottom:2px solid transparent}
.lsw a:hover{color:#fff}
.lsw a[aria-current]{color:#fff;border-bottom-color:var(--brass-l)}
.lsw .lc{font-weight:500;color:var(--brass-l)}
.hd-row{display:flex;align-items:center;gap:14px;min-height:var(--hdr)}
.brand{display:inline-flex;align-items:center;gap:11px;min-height:44px;margin-right:auto;color:var(--ink);text-decoration:none}
.brand:hover{color:var(--ink)}
.brand .gem{width:36px;height:36px;flex:none;transition:transform .5s cubic-bezier(.2,.8,.2,1)}
.brand:hover .gem{transform:rotate(45deg)}
.bn b{display:block;font:700 25px/1 var(--f-d);letter-spacing:-.02em}
.bn small{display:block;margin-top:4px;font:500 10.5px/1.1 var(--f-m);letter-spacing:.12em;text-transform:uppercase;color:var(--muted)}
.menu-btn{display:inline-flex;align-items:center;gap:10px;min-height:44px;padding:0 14px;border:1px solid var(--ink);border-radius:3px;background:transparent;color:var(--ink);font:600 15px/1 var(--f-b);cursor:pointer}
.menu-btn:hover{background:var(--ink);color:var(--sheet)}
.mb-ic{position:relative;width:18px;height:12px}
.mb-ic i{position:absolute;left:0;right:0;height:2px;background:currentColor;transition:transform .22s}
.mb-ic i:first-child{top:1px}.mb-ic i:last-child{bottom:1px}
.hd.is-open .mb-ic i:first-child{transform:translateY(4px) rotate(45deg)}
.hd.is-open .mb-ic i:last-child{transform:translateY(-4px) rotate(-45deg)}
.nav{display:none;position:absolute;left:0;right:0;top:100%;background:var(--sheet);border-bottom:1px solid var(--ink);box-shadow:0 24px 40px -24px rgba(7,58,44,.45);padding:6px 16px 22px;max-height:calc(100dvh - var(--hdr));overflow:auto}
.hd.is-open .nav{display:block}
.nav ol{list-style:none;margin:0 auto;padding:0;max-width:1240px}
.nav a{display:flex;align-items:center;gap:14px;min-height:54px;padding:6px 2px;border-bottom:1px solid var(--line-2);color:var(--ink);text-decoration:none;font:500 17px/1.3 var(--f-b)}
.nav .n{flex:none;width:24px;font:500 12px/1 var(--f-m);color:var(--ruby)}
.nav a[aria-current=page]{color:var(--jade);font-weight:700}
.nav .nav-cta{display:flex;width:100%;max-width:1240px;margin:18px auto 0;min-height:52px;padding:0 22px;justify-content:center;gap:10px;border:0;color:#fff;font:600 16px/1.2 var(--f-b)}
.nav .nav-cta:hover{color:#fff}
.hd-cta{display:none}
@media (min-width:1080px){
  .menu-btn{display:none}
  .nav{display:block;position:static;background:none;border:0;box-shadow:none;padding:0;max-height:none;overflow:visible}
  .nav ol{display:flex;gap:2px;max-width:none}
  .nav a{position:relative;min-height:44px;border:0;padding:0 11px;gap:7px;font-size:15px;font-weight:500}
  .nav .n{width:auto;font-size:10.5px}
  .nav a::after{content:"";position:absolute;left:11px;right:11px;bottom:5px;height:2px;background:var(--ruby);transform:scaleX(0);transform-origin:left;transition:transform .22s}
  .nav a:hover::after,.nav a[aria-current=page]::after{transform:scaleX(1)}
  .nav a[aria-current=page]{font-weight:600}
  .nav .nav-cta{display:none}
}
@media (min-width:1320px){.hd-cta{display:inline-flex}}

/* ---------- guilloche ---------- */
.gu{position:absolute;left:0;top:0;width:100%;height:100%;color:var(--jade);pointer-events:none;opacity:.16}
.gu-hero{height:min(78%,560px);-webkit-mask-image:linear-gradient(180deg,#000 10%,transparent);mask-image:linear-gradient(180deg,#000 10%,transparent)}
.gu-ph{opacity:.12;-webkit-mask-image:linear-gradient(90deg,transparent 20%,#000 90%);mask-image:linear-gradient(90deg,transparent 20%,#000 90%)}
.gu-cta{color:#fff;opacity:.09}

/* ---------- home hero ---------- */
.assay{position:relative;overflow:clip;padding:clamp(28px,5vw,72px) 0 clamp(44px,6vw,92px);border-bottom:1px solid var(--line)}
.assay-grid{position:relative;display:grid;grid-template-columns:minmax(0,1fr);gap:40px}
.kicker{display:inline-flex;align-items:center;gap:10px;margin:0 0 20px;padding:7px 12px;background:var(--sheet);border:1px solid color-mix(in srgb,var(--ruby) 45%,transparent);color:var(--ruby);font:500 12.5px/1.35 var(--f-m);letter-spacing:.05em;text-transform:uppercase}
.kicker::before{content:"";flex:none;width:10px;height:10px;background:var(--ruby);clip-path:var(--oct)}
.assay h1{margin:0 0 20px;font-size:clamp(2rem,1.25rem + 3.3vw,3.85rem);line-height:1.1;font-weight:600;font-variation-settings:"SOFT" 50}
.lead p{margin:0;font-size:clamp(1.05rem,1rem + .3vw,1.2rem);line-height:1.7;color:var(--text);max-width:62ch}
.acts{display:flex;flex-wrap:wrap;gap:12px;margin:28px 0 30px}
.specs{list-style:none;margin:0;padding:0;border-top:1px solid var(--ink);max-width:560px}
.specs li{display:flex;align-items:center;gap:14px;padding:11px 0;border-bottom:1px solid var(--line);font:500 15.5px/1.45 var(--f-b);color:var(--ink)}
.specs li::before{content:"";flex:none;width:12px;height:12px;background:var(--jade);clip-path:var(--oct)}
.tray{position:relative;background:var(--sheet);border:1px solid var(--ink);box-shadow:0 40px 70px -40px rgba(7,58,44,.5);container-type:inline-size;scroll-margin-top:calc(var(--hdr) + 16px);align-self:start}
.tray-hd{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:50px;padding:6px 8px 6px 14px;background:var(--jade-t);border-bottom:1px solid var(--ink);font:500 12px/1.3 var(--f-m);letter-spacing:.07em;text-transform:uppercase;color:var(--jade-d)}
.cm{position:absolute;width:14px;height:14px;border:0 solid var(--brass);pointer-events:none}
.cm1{left:-9px;top:-9px;border-left-width:1px;border-top-width:1px}
.cm2{right:-9px;top:-9px;border-right-width:1px;border-top-width:1px}
.cm3{left:-9px;bottom:-9px;border-left-width:1px;border-bottom-width:1px}
.cm4{right:-9px;bottom:-9px;border-right-width:1px;border-bottom-width:1px}
.seal{display:inline-grid;place-items:center;flex:none;width:44px;height:44px;background:var(--ruby);color:#fff;font:600 13px/1 var(--f-m);letter-spacing:0;clip-path:var(--oct)}
.seal-s{width:38px;height:38px;font-size:12px}
@media (min-width:980px){
  .assay-grid{grid-template-columns:minmax(0,1.04fr) minmax(0,.96fr);gap:clamp(40px,5vw,72px);align-items:start}
  .assay-copy{padding-top:8px}
}

/* ---------- report fields ---------- */
.report{padding:clamp(24px,4vw,56px) 0 clamp(48px,6vw,88px)}
.field{display:grid;grid-template-columns:minmax(0,1fr);gap:8px 40px;padding:34px 0 30px;border-top:1px solid var(--line)}
.report>.field:first-child,.prose>.field:first-child{border-top:0}
.field-plain{padding-top:26px}
.f-gut{display:flex;align-items:center;gap:10px;color:var(--ruby);font:500 12.5px/1 var(--f-m);letter-spacing:.08em;text-transform:uppercase}
.f-gut:empty{display:none}
.facet{width:18px;height:18px;flex:none;color:var(--ruby)}
.f-body{min-width:0;max-width:72ch}
.f-body h2{margin:0 0 16px;font-size:clamp(1.55rem,1.15rem + 1.5vw,2.3rem);line-height:1.18}
.f-body h3{margin:1.6em 0 .5em;font-size:1.3rem;line-height:1.3}
.f-body p{margin:0 0 1em}
.f-body ul,.f-body ol{margin:0 0 1.1em;padding:0;list-style:none}
.f-body li{position:relative;margin:.55em 0;padding-left:28px}
.f-body ul>li::before{content:"";position:absolute;left:5px;top:.66em;width:9px;height:9px;background:var(--jade);clip-path:var(--oct)}
.f-body ol{counter-reset:li}
.f-body ol>li{counter-increment:li}
.f-body ol>li::before{content:counter(li,decimal-leading-zero);position:absolute;left:0;top:.28em;font:500 12.5px/1.5 var(--f-m);color:var(--ruby)}
.f-body strong{color:var(--ink);font-weight:600}
.f-body blockquote{margin:1.2em 0;padding:4px 0 4px 18px;border-left:3px solid var(--brass);color:var(--ink)}
.f-body table{display:block;max-width:100%;overflow-x:auto;border-collapse:collapse;margin:0 0 1.2em;font-size:15px}
.f-body th,.f-body td{padding:10px 12px;border:1px solid var(--line);text-align:left;vertical-align:top}
.f-body th{background:var(--jade-t);color:var(--ink);font-weight:600}
@media (min-width:820px){
  .field{grid-template-columns:9.5rem minmax(0,1fr)}
  .f-gut{flex-direction:column;align-items:flex-start;gap:12px;padding-top:12px;position:sticky;top:calc(var(--hdr) + 28px);align-self:start}
  .f-gut:empty{display:block}
  .report .f-body{font-size:17.5px}
}
@media (min-width:1180px){.report .field{grid-template-columns:13rem minmax(0,1fr)}}

/* ---------- FAQ ledger ---------- */
.qa{border-top:1px solid var(--ink)}
.qa details{border-bottom:1px solid var(--line)}
.qa summary{display:grid;grid-template-columns:minmax(0,1fr) 24px;align-items:center;gap:16px;min-height:58px;padding:14px 0;cursor:pointer;list-style:none;font:600 17px/1.45 var(--f-b);color:var(--ink)}
.qa summary::-webkit-details-marker{display:none}
.qa summary:hover{color:var(--jade)}
.qa summary i{justify-self:end;width:13px;height:13px;border:1.5px solid var(--jade);transform:rotate(45deg);transition:background-color .2s,transform .25s}
.qa details[open] summary i{background:var(--jade);transform:rotate(135deg)}
.qa-a{padding:0 0 18px}
.qa-a p{margin:0 0 .8em}

/* ---------- inner page head ---------- */
.ph{position:relative;overflow:clip;padding:26px 0 44px;border-bottom:1px solid var(--line)}
.ph-grid{position:relative;display:grid;grid-template-columns:minmax(0,1fr);gap:18px}
.crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:0 8px;font:500 12.5px/1.3 var(--f-m);letter-spacing:.04em;color:var(--muted)}
.crumbs a{display:inline-flex;align-items:center;min-height:44px;color:var(--jade)}
.crumbs .sep{color:var(--line)}
.crumbs span[aria-current]{color:var(--ink)}
.ph h1{margin:0;font-size:clamp(1.9rem,1.2rem + 2.9vw,3.35rem);line-height:1.12;max-width:22ch}
.cert{margin:8px 0 0;background:var(--sheet);border:1px solid var(--ink);font-size:15px}
.cert::before{content:"";display:block;height:12px;border-bottom:1px solid var(--ink);background:repeating-linear-gradient(135deg,var(--jade) 0 1px,transparent 1px 7px)}
.cert div{display:grid;grid-template-columns:minmax(6.5rem,.8fr) minmax(0,1.4fr);gap:12px;padding:10px 14px;border-top:1px solid var(--line-2)}
.cert div:first-child{border-top:0}
.cert dt{font:500 11.5px/1.55 var(--f-m);letter-spacing:.07em;text-transform:uppercase;color:var(--muted)}
.cert dd{margin:0;font:600 14.5px/1.45 var(--f-b);color:var(--ink)}
@media (min-width:980px){
  .ph{padding:30px 0 56px}
  .ph-grid{grid-template-columns:minmax(0,1fr) 21rem;column-gap:64px}
  .crumbs,.ph h1,.ph .lead{grid-column:1}
  .cert{grid-column:2;grid-row:1/span 3;align-self:end;margin:0}
}

/* ---------- inner body ---------- */
.doc{display:grid;grid-template-columns:minmax(0,1fr);gap:24px;padding:28px 0 64px}
.rail{min-width:0}
.toc{background:var(--sheet);border:1px solid var(--line)}
.toc summary{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:50px;padding:0 16px;cursor:pointer;list-style:none;font:500 12.5px/1.2 var(--f-m);letter-spacing:.09em;text-transform:uppercase;color:var(--ink)}
.toc summary::-webkit-details-marker{display:none}
.toc summary i{width:9px;height:9px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg) translate(-2px,-2px);transition:transform .2s}
.toc[open] summary i{transform:rotate(225deg)}
.toc ol{list-style:none;margin:0;padding:4px 0 10px;border-top:1px solid var(--line-2)}
.toc a{display:grid;grid-template-columns:2.1rem minmax(0,1fr);align-items:start;min-height:44px;padding:10px 16px 10px 14px;border-left:2px solid transparent;color:var(--text);text-decoration:none;font-size:15px;line-height:1.45}
.toc a:hover{color:var(--jade);background:var(--paper)}
.toc a[aria-current]{border-left-color:var(--ruby);color:var(--ink);background:var(--paper);font-weight:500}
.toc .n{font:500 12px/1.9 var(--f-m);color:var(--ruby)}
.loupe{display:none}
.prose .field{padding:30px 0 26px}
.prose>.field:first-child{padding-top:6px}
@media (min-width:820px){.prose .field{grid-template-columns:5.5rem minmax(0,1fr);gap:8px 28px}}
@media (min-width:1100px){
  .doc{grid-template-columns:minmax(0,1fr) 19rem;column-gap:clamp(40px,5vw,72px);padding-top:40px}
  .rail{grid-column:2;grid-row:1;position:sticky;top:calc(var(--hdr) + 24px);align-self:start;display:grid;gap:18px;max-height:calc(100vh - var(--hdr) - 48px);overflow:auto}
  .prose{grid-column:1;grid-row:1}
  .toc summary{cursor:default}
  .loupe{display:grid;justify-items:start;gap:10px;padding:22px;background:var(--jade-d);color:#D6E2DA}
  .loupe strong{font:600 20px/1.25 var(--f-d);color:#fff}
  .loupe p{margin:0 0 6px;font-size:15px;line-height:1.6}
  .loupe .btn{background:var(--sheet);color:var(--jade-d)}
  .lp-ring{display:grid;place-items:center;width:64px;height:64px;border-radius:50%;border:1.5px solid var(--brass-l);box-shadow:inset 0 0 0 6px var(--jade-d),inset 0 0 0 7px rgba(216,189,130,.5)}
  .lp-ring .gem{width:30px;height:30px}
}

/* ---------- CTA band ---------- */
.cta{position:relative;overflow:clip;background:var(--jade-d);color:#D6E2DA}
.cta-in{position:relative;display:grid;gap:22px;padding:48px 0}
.cta p{margin:0;max-width:44ch;font:500 clamp(1.25rem,1rem + 1vw,1.75rem)/1.4 var(--f-d);color:#fff}
@media (min-width:820px){.cta-in{grid-template-columns:minmax(0,1fr) auto;align-items:center;gap:40px;padding:56px 0}}

/* ---------- related: specimen tags ---------- */
.tags{padding:clamp(44px,6vw,80px) 0;border-top:1px solid var(--line);background:linear-gradient(var(--paper),color-mix(in srgb,var(--jade-t) 45%,var(--paper)))}
.tags-h{margin:0 0 26px;font-size:clamp(1.5rem,1.2rem + 1.2vw,2.1rem);line-height:1.2}
.tag-grid{container-type:inline-size;list-style:none;margin:0;padding:0;display:grid;gap:14px;grid-template-columns:repeat(auto-fill,minmax(min(100%,19rem),1fr))}
.tag{position:relative;display:grid;align-content:start;gap:6px;height:100%;min-height:44px;padding:18px 20px 20px 50px;background:var(--sheet);border:1px solid var(--line);color:var(--text);text-decoration:none;clip-path:polygon(0 0,calc(100% - 20px) 0,100% 20px,100% 100%,0 100%);transition:transform .25s cubic-bezier(.2,.8,.2,1),border-color .2s}
.tag::after{content:"";position:absolute;top:0;right:0;width:20px;height:20px;background:linear-gradient(225deg,transparent 50%,var(--line) 50%,var(--jade-t) calc(50% + 1px))}
.tag:hover{border-color:var(--jade);transform:translateY(-3px);color:var(--text)}
.hole{position:absolute;left:18px;top:23px;width:13px;height:13px;border-radius:50%;border:1.5px solid var(--brass);background:var(--paper)}
.hole::after{content:"";position:absolute;left:50%;bottom:100%;width:1px;height:24px;background:var(--brass);opacity:.6}
.t-n{font:500 12px/1.4 var(--f-m);letter-spacing:.08em;color:var(--ruby)}
.tag strong{font:600 19px/1.3 var(--f-d);color:var(--ink)}
.tag:hover strong{color:var(--jade)}
.tag .d{font-size:15px;line-height:1.55;color:var(--muted)}

/* ---------- footer ---------- */
.ft{background:var(--ink);color:#C3CCC6;padding:56px 0 26px}
.ft-grid{display:grid;grid-template-columns:minmax(0,1fr);gap:34px}
.ft .brand,.ft .brand:hover{color:#fff}
.ft .bn small{color:#A4AFA8}
.ft p{margin:18px 0 0;max-width:54ch;font-size:15px;line-height:1.7}
.ft h2{margin:0 0 8px;font:500 12px/1.3 var(--f-m);letter-spacing:.12em;text-transform:uppercase;color:var(--brass-l)}
.ft ul{list-style:none;margin:0;padding:0}
.ft li a{display:flex;align-items:center;min-height:46px;border-bottom:1px solid rgba(255,255,255,.09);color:#E8EEE9;text-decoration:none;font-size:15.5px;line-height:1.35}
.ft li a:hover{color:#fff;text-decoration:underline}
.ft :focus-visible{outline-color:var(--brass-l)}
.ft-bottom{display:flex;flex-wrap:wrap;align-items:center;gap:10px 16px;margin-top:44px;padding-top:22px;border-top:1px solid rgba(255,255,255,.14);font:500 13px/1.4 var(--f-m);letter-spacing:.03em}
.ft-bottom .cp{margin-left:auto}
@media (min-width:820px){.ft-grid{grid-template-columns:minmax(0,1.5fr) minmax(0,1fr) minmax(0,1fr);gap:56px}}

/* ---------- 404 ---------- */
.nf .ph{padding:64px 0 90px}
.nf-in{position:relative;max-width:720px}
.nf-code{margin:0;font:600 clamp(5rem,20vw,10rem)/1 var(--f-d);color:var(--jade-t);-webkit-text-stroke:1.5px var(--jade)}
.nf h1{margin:10px 0 12px;font-size:clamp(1.9rem,1.4rem + 2vw,2.8rem)}
.nf-in>p:not(.nf-code){margin:0 0 24px}

/* ---------- motion ---------- */
@media (prefers-reduced-motion:no-preference){
  html{scroll-behavior:smooth}
  .gu-hero g{animation:drift 60s linear infinite alternate}
  .tray{animation:settle .7s cubic-bezier(.2,.8,.2,1) both}
}
@keyframes drift{to{transform:translateX(-100px)}}
@keyframes settle{from{transform:translateY(14px)}to{transform:none}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}}
@media print{.hd,.rail,.cta,.tags,.gu{display:none}}