/* ============================================================
   SERAPHIN CARBON — design system
   Near-black ground, one signal red, engineering precision.
   No shadows. No gradients. No radius.
   ============================================================ */

:root{
  --bg:#0B0C0E;
  --surface:#16181C;
  --surface-2:#1E2126;
  --ink:#F2F3F4;
  --muted:#8B9096;
  --line:#2A2E34;
  --red:#ED1C24;
  --red-hi:#FF2F36;

  --display:"Archivo","Helvetica Neue",system-ui,sans-serif;
  --body:"Manrope","Helvetica Neue",system-ui,sans-serif;

  --wrap:1180px;
  --bleed:clamp(1.25rem,4vw,3rem);

  --s-eyebrow:.7rem;
  --s-small:.86rem;
  --s-body:1.02rem;
  --s-lead:clamp(1.1rem,1.5vw,1.35rem);
  --s-h3:clamp(1.2rem,2vw,1.45rem);
  --s-h2:clamp(1.9rem,3.6vw,3rem);
  --s-h1:clamp(2.6rem,7vw,6.4rem);

  --gap-sm:16px;
  --gap-md:32px;
  --gap-lg:64px;
  /* Section rhythm calibrated against apple.com/macbook-pro, which runs
     144px standard and 216px where a section needs more air. */
  --gap-xl:clamp(88px,13vw,176px);
  --gap-2xl:clamp(120px,19vw,264px);
}

/* ---------- carbon twill ----------
   A real 2x2 twill: paired tows running one way in one quadrant,
   the other way in the next, in a 2-over-2 checker. 16px repeat is a
   believable weave scale on screen. Kept at 4-9% opacity so it reads as
   material under the content, never as decoration on top of it. */
:root{
  --twill:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 16 16'%3E%3Cg stroke='%23ffffff' fill='none' stroke-width='1.6'%3E%3Cg opacity='.95'%3E%3Cpath d='M-1 1 L9 11 M-1 5 L9 15'/%3E%3Cpath d='M7 -1 L17 9 M7 3 L17 13'/%3E%3C/g%3E%3Cg opacity='.4'%3E%3Cpath d='M9 -1 L-1 9 M9 3 L-1 13'/%3E%3Cpath d='M17 1 L7 11 M17 5 L7 15'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

*{box-sizing:border-box}

body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:var(--body);
  font-size:var(--s-body);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}

h1,h2,h3,h4{
  font-family:var(--display);
  font-weight:800;
  line-height:1.0;
  letter-spacing:-.025em;
  margin:0;
}
h1{font-size:var(--s-h1);line-height:.95;letter-spacing:-.035em}
h2{font-size:var(--s-h2)}
h3{font-size:var(--s-h3);letter-spacing:-.015em}
p{margin:0}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}

:focus-visible{outline:2px solid var(--red);outline-offset:3px}

.sr-skip{position:absolute;left:-9999px}
.sr-skip:focus{left:0;top:0;background:var(--red);color:#fff;padding:.85rem 1.4rem;z-index:200;font-weight:700}

.wrap{max-width:var(--wrap);margin-inline:auto;padding-inline:var(--bleed)}

/* ---------- texture helper ---------- */
.tex{position:relative;isolation:isolate}
.tex::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background-image:var(--twill);
  background-size:16px 16px;
  opacity:.035;
  pointer-events:none;
}
.tex-strong::before{opacity:.09}

/* Woven surface: twill plus a soft diagonal sheen, for panels that should
   read as an actual carbon part rather than a textured background. */
.tex-weave{position:relative;isolation:isolate;background:var(--surface)}
.tex-weave::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background-image:var(--twill);
  background-size:16px 16px;
  opacity:.10;
}
.tex-weave::after{
  content:"";position:absolute;inset:0;z-index:-1;
  background:linear-gradient(118deg,
    rgba(255,255,255,.055) 0%,
    rgba(255,255,255,0) 34%,
    rgba(0,0,0,.16) 72%);
  pointer-events:none;
}

/* ---------- type helpers ---------- */
.eyebrow{
  font-family:var(--display);
  font-size:var(--s-eyebrow);
  font-weight:700;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--red);
  margin:0 0 1.6rem;
}
.eyebrow-muted{color:var(--muted)}
.lead{font-size:var(--s-lead);color:var(--muted);line-height:1.45;max-width:46ch}
.measure{max-width:52ch}
.muted{color:var(--muted)}

/* the signature: italic spec figure */
.fig{
  font-family:var(--display);
  font-weight:800;
  font-style:italic;
  letter-spacing:-.03em;
  line-height:1;
  display:block;
}
.fig .unit{
  font-family:var(--body);
  font-style:normal;
  font-weight:400;
  font-size:.34em;
  color:var(--muted);
  margin-left:.28rem;
  letter-spacing:0;
}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:52px;padding:0 1.75rem;
  font-family:var(--display);
  font-size:.78rem;font-weight:800;
  letter-spacing:.1em;text-transform:uppercase;
  border:1px solid transparent;border-radius:0;
  cursor:pointer;
  transition:background .18s ease,border-color .18s ease,color .18s ease;
}
.btn-primary{background:var(--red);color:#fff}
.btn-primary:hover{background:var(--red-hi)}
.btn-ghost{border-color:var(--line);color:var(--ink);background:transparent}
.btn-ghost:hover{border-color:var(--ink)}
.btn-sm{min-height:42px;padding:0 1.15rem;font-size:.72rem}

/* ---------- header ---------- */
.s-top{
  position:sticky;top:0;z-index:50;
  background:rgba(11,12,14,.9);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
  isolation:isolate;
}
/* carbon weave in the chrome — header and footer are the "material"
   edges of the page, so the texture lives here rather than behind copy */
.s-top::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background-image:var(--twill);
  background-size:16px 16px;
  opacity:.11;
  pointer-events:none;
}
.s-top .wrap{display:flex;align-items:center;gap:2rem;min-height:72px}
.s-logo img{height:24px;width:auto;mix-blend-mode:screen}
.s-nav{display:none;gap:1.7rem;margin-left:auto}
@media(min-width:980px){.s-nav{display:flex}}
.s-nav a{
  font-family:var(--display);
  font-size:.76rem;font-weight:700;
  letter-spacing:.1em;text-transform:uppercase;
  color:var(--muted);
  padding:.35rem 0;border-bottom:2px solid transparent;
  transition:color .15s,border-color .15s;
}
.s-nav a:hover,.s-nav a[aria-current="page"]{color:var(--ink);border-bottom-color:var(--red)}

/* mobile nav, no JS */
.s-mnav{position:relative;margin-left:auto}
@media(min-width:980px){.s-mnav{display:none}}
.s-mnav summary{
  list-style:none;cursor:pointer;
  display:inline-flex;align-items:center;gap:.5rem;
  min-height:44px;padding:.4rem .9rem;
  border:1px solid var(--line);
  font-family:var(--display);font-size:.72rem;font-weight:700;
  letter-spacing:.1em;text-transform:uppercase;
  user-select:none;
}
.s-mnav summary::-webkit-details-marker{display:none}
.s-mnav[open] summary{border-color:var(--ink)}
.s-mnav-ic{width:15px;height:11px;position:relative;display:inline-block}
.s-mnav-ic::before,.s-mnav-ic::after,.s-mnav-ic i{content:"";position:absolute;left:0;right:0;height:1.5px;background:currentColor}
.s-mnav-ic::before{top:0}.s-mnav-ic i{top:5px}.s-mnav-ic::after{bottom:0}
.s-mnav-panel{
  position:absolute;right:0;top:calc(100% + .55rem);min-width:225px;
  background:var(--surface);border:1px solid var(--line);z-index:60;
}
.s-mnav-panel a{display:block;padding:.9rem 1.2rem;border-bottom:1px solid var(--line);font-size:.95rem}
.s-mnav-panel a:last-child{border-bottom:0}
.s-mnav-panel a:hover{background:var(--surface-2)}

/* ---------- sections ---------- */
.sec{padding:var(--gap-xl) 0}
.sec-air{padding:var(--gap-2xl) 0}
.sec-line{border-top:1px solid var(--line)}
.sec-surface{background:var(--surface)}
.head{max-width:52ch;margin-bottom:clamp(3.5rem,7vw,6rem)}
.head h2{margin-bottom:1.75rem}
.head p{color:var(--muted)}

/* ---------- spec strip ---------- */
.strip{background:var(--surface);border-block:1px solid var(--line);position:relative;isolation:isolate}
.strip::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background-image:var(--twill);background-size:16px 16px;opacity:.05;
}
.strip-grid{display:grid;grid-template-columns:repeat(2,1fr)}
@media(min-width:880px){.strip-grid{grid-template-columns:repeat(4,1fr)}}
.strip .cell{padding:clamp(2.75rem,5vw,4.25rem) clamp(1.75rem,3vw,2.75rem) clamp(2.75rem,5vw,4.25rem) 0;border-right:1px solid var(--line)}
.strip .cell:last-child{border-right:0}
@media(max-width:879px){
  .strip .cell:nth-child(2n){border-right:0}
  .strip .cell:nth-child(-n+2){border-bottom:1px solid var(--line)}
}
.strip .fig{font-size:clamp(2rem,3.8vw,3.1rem)}
.strip .cap{display:block;margin-top:.95rem;font-size:var(--s-small);color:var(--muted);max-width:24ch;line-height:1.45}

/* ---------- range grid ---------- */
.range{display:grid;gap:1px;background:var(--line);border:1px solid var(--line)}
@media(min-width:700px){.range{grid-template-columns:repeat(2,1fr)}}
@media(min-width:1040px){.range{grid-template-columns:repeat(3,1fr)}}
.card{background:var(--surface);padding:clamp(2rem,3vw,3rem);display:flex;flex-direction:column;transition:background .2s}
.card:hover{background:var(--surface-2)}
.card-img{
  aspect-ratio:5/4;
  background:#0f1114;
  background-image:var(--twill);
  background-size:16px 16px;
  margin-bottom:1.9rem;overflow:hidden;
}
.card-img img{width:100%;height:100%;object-fit:cover}
.card h3{margin-bottom:.45rem}
.card .line{font-size:var(--s-small);color:var(--muted);margin-bottom:1.6rem}
.card dl{display:flex;gap:2rem;margin:0 0 1.6rem}
.card dt{font-size:.62rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);margin-bottom:.25rem}
.card dd{margin:0;font-family:var(--display);font-weight:700;font-style:italic;font-size:1.22rem;letter-spacing:-.02em}
.card .price{margin-top:auto;font-family:var(--display);font-size:.82rem;font-weight:700;letter-spacing:.08em;text-transform:uppercase}

/* ---------- document cards (the moat) ---------- */
.docs{display:grid;gap:clamp(2.5rem,5vw,4.5rem)}
@media(min-width:820px){.docs{grid-template-columns:repeat(3,1fr)}}
.doc{border-top:2px solid var(--red);padding-top:2rem}
.doc h3{margin-bottom:.55rem}
.doc p{font-size:var(--s-small);color:var(--muted)}

/* ---------- footer ---------- */
.s-foot{
  border-top:1px solid var(--line);
  padding:var(--gap-xl) 0 var(--gap-md);
  font-size:var(--s-small);
  position:relative;
  isolation:isolate;
  background:var(--surface);
}
.s-foot::before{
  content:"";position:absolute;inset:0;z-index:-1;
  background-image:var(--twill);
  background-size:16px 16px;
  opacity:.11;
  pointer-events:none;
}
.s-foot::after{
  content:"";position:absolute;inset:0;z-index:-1;
  background:linear-gradient(180deg, rgba(255,255,255,.03), rgba(0,0,0,.22));
  pointer-events:none;
}
.s-fgrid{display:grid;gap:3.5rem;margin-bottom:4rem}
@media(min-width:800px){.s-fgrid{grid-template-columns:1.5fr 1fr 1fr 1fr}}
.s-foot h4{font-family:var(--display);font-size:.68rem;font-weight:700;letter-spacing:.16em;text-transform:uppercase;color:var(--muted);margin:0 0 1.05rem}
.s-foot ul{list-style:none;padding:0;margin:0;display:grid;gap:.6rem}
.s-foot a{color:var(--muted)}
.s-foot a:hover{color:var(--ink)}
.s-fbase{border-top:1px solid var(--line);padding-top:2rem;color:var(--muted);font-size:.8rem;display:flex;flex-wrap:wrap;gap:1.2rem;justify-content:space-between}

/* ---------- motion ---------- */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.01ms!important;
    animation-iteration-count:1!important;
    transition-duration:.01ms!important;
    scroll-behavior:auto!important;
  }
}