/* SeaBrick Society, version 4. Tidal Paper system (stylebook, 4 November 2026) on the SeaBrick logo identity:
   ocean #005593, sea green #52B09F, Noto Sans. Paper ground, deep reading ink, washes only at the edges. */
@font-face{font-family:"Noto Sans";src:url("fonts/NotoSans-Regular.woff2") format("woff2");font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:"Noto Sans";src:url("fonts/NotoSans-Bold.woff2") format("woff2");font-weight:700;font-style:normal;font-display:swap}
@font-face{font-family:"Noto Sans";src:url("fonts/NotoSans-Italic.woff2") format("woff2");font-weight:400;font-style:italic;font-display:swap}
:root{
  --ocean:#005593; --ocean-deep:#004574; --ocean-ink:#12343E; --ocean-soft:#2F6FA3;
  --sea:#52B09F; --sea-dark:#28655B; --sea-soft:#E7F3ED;
  --foam:#F8FAF7; --paper:#F8FAF7; --mist:#E5F0F4; --line:#CBD9DA; --control:#6C858B; --rust:#9B4938;
  --sand:#F8FAF7; --sand-dark:#CBD9DA;
  --text:#12343E; --muted:#526B73; --white:#fff;
  --max:1280px; --gutter:clamp(20px,5.55vw,80px); --radius:10px; --radius-s:6px; --shadow:none;
  --font:"Noto Sans",Arial,sans-serif;
  --mono:Consolas,"Cascadia Code","SF Mono",Menlo,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:var(--font);font-size:18px;line-height:1.65;color:var(--text);background:var(--paper)}
img,svg{max-width:100%;height:auto;display:block}
a{color:var(--ocean);text-decoration:underline;text-underline-offset:.22em;text-decoration-thickness:1px}
a:hover{text-decoration-thickness:2px}
h1,h2,h3,h4{font-weight:700;line-height:1.12;color:var(--ocean-ink);margin:0 0 .5em;letter-spacing:-.03em}
h1{font-size:clamp(40px,5.25vw,72px);line-height:1.08}
h2{font-size:clamp(30px,3.1vw,42px);line-height:1.18}
h3{font-size:24px;letter-spacing:-.02em;line-height:1.25}
h4{font-size:18px;letter-spacing:0}
p{margin:0 0 1em}
.wrap{width:min(100% - 2*var(--gutter),var(--max));margin:0 auto;padding:0}
.narrow{max-width:66ch}
.eyebrow{display:inline-block;font-size:12px;letter-spacing:.13em;text-transform:uppercase;font-weight:700;color:var(--sea-dark);margin-bottom:1em}
.lead{font-size:20px;color:var(--text);line-height:1.7}
.muted{color:var(--muted)}
.small{font-size:14px;line-height:1.5}
.center{text-align:center}
hr{border:0;border-top:1px solid var(--line);margin:48px 0}
:focus-visible{outline:3px solid var(--ocean);outline-offset:4px;box-shadow:0 0 0 3px #fff}
::selection{background:var(--mist)}

/* header */
.preview-band{background:var(--ocean-ink);color:#fff;font-size:11px;text-align:center;padding:7px 12px;letter-spacing:.07em;text-transform:uppercase}
header.site{position:sticky;top:0;z-index:50;background:rgba(248,250,247,.94);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;gap:32px;height:96px;position:relative}
.brand{display:flex;align-items:center;gap:14px;text-decoration:none}
.brand img{height:36px;width:auto}
.brand .sub{font-size:11px;letter-spacing:.13em;text-transform:uppercase;color:var(--sea-dark);font-weight:700;border-left:1px solid var(--line);padding-left:14px;line-height:1.25}
.menu{display:flex;gap:28px;align-items:center;list-style:none;margin:0;padding:0}
.menu a{display:block;padding:8px 0;color:var(--ocean-ink);font-size:15px;text-decoration:none;border-bottom:2px solid transparent}
.menu a:hover{color:var(--ocean);border-bottom-color:var(--line)}
.menu a.active{color:var(--ocean);border-bottom-color:var(--ocean)}
.menu a.cta{background:var(--ocean);color:#fff;border:1px solid var(--ocean);border-radius:var(--radius-s);padding:10px 20px;font-weight:700;margin-left:4px;min-height:44px;display:inline-flex;align-items:center}
.menu a.cta:hover{background:var(--ocean-deep)}
.burger{display:none;background:none;border:1px solid var(--control);border-radius:var(--radius-s);padding:9px 10px;cursor:pointer;min-width:44px;min-height:44px}
.burger span{display:block;width:20px;height:2px;background:var(--ocean-ink);margin:4px 0}
@media(max-width:1119px){.menu{gap:18px}.menu a{font-size:14px}}
@media(max-width:860px){
  .nav{height:82px}
  .brand img{height:30px}
  .burger{display:block}
  .menu{display:none;position:absolute;left:calc(-1*var(--gutter));right:calc(-1*var(--gutter));top:82px;background:var(--paper);flex-direction:column;align-items:stretch;gap:0;padding:8px var(--gutter) 20px;border-bottom:1px solid var(--line)}
  .menu.open{display:flex}
  .menu a{padding:12px 0;border-bottom:1px solid var(--line);font-size:16px}
  .menu a.active{border-bottom-color:var(--line)}
  .menu a.cta{margin:14px 0 0;justify-content:center}
  .brand .sub{display:none}
}

/* hero: a generous opening with the wash on the quiet half */
.hero{position:relative;overflow:hidden;isolation:isolate;background:var(--paper)}
.hero::before{content:"";position:absolute;inset:-40px -60px 0 35%;z-index:-2;background:url("art/tidal-ocean-1600.webp") center 70%/cover no-repeat;opacity:.6;pointer-events:none}
.hero::after{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,rgba(248,250,247,1) 0%,rgba(248,250,247,.96) 38%,rgba(248,250,247,.55) 58%,rgba(248,250,247,0) 78%);pointer-events:none}
.hero .wrap{display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center;padding-top:72px;padding-bottom:64px;min-height:600px}
.hero h1{margin-bottom:.4em;max-width:12ch}
.hero h1 em{font-style:normal;color:var(--ocean)}
.hero .lead{max-width:34rem}
.hero-note{font-size:14px;color:var(--muted);margin-top:10px;line-height:1.5}
.waves{display:none}
@media(max-width:860px){
  .hero::before{inset:auto -20px 0 0;height:60%;opacity:.5;background-position:62% bottom}
  .hero::after{background:linear-gradient(rgba(248,250,247,1) 0%,rgba(248,250,247,.95) 35%,rgba(248,250,247,.2) 70%,rgba(248,250,247,0) 100%)}
  .hero .wrap{grid-template-columns:1fr;padding-top:40px;padding-bottom:40px;min-height:0}
  .hero h1{max-width:none}
}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:12px;min-height:48px;padding:10px 22px;border-radius:var(--radius-s);font-weight:700;font-size:15px;border:1px solid var(--ocean);text-decoration:none;transition:background .16s,border-color .16s}
.btn.primary{background:var(--ocean);color:#fff}
.btn.primary:hover{background:var(--ocean-deep);border-color:var(--ocean-deep)}
.btn.ghost{border-color:var(--ocean);color:var(--ocean);background:#fff}
.btn.ghost:hover{background:var(--mist)}
.btn-row{display:flex;gap:16px;flex-wrap:wrap;align-items:center;margin:28px 0 16px}

/* sections */
section.band{padding:96px 0}
section.band.soft{background:var(--paper)}
section.band.sand{background:var(--paper)}
section.band.deep{background:var(--white);color:var(--text);border-top:1px solid var(--line);border-bottom:1px solid var(--line);position:relative;isolation:isolate;overflow:hidden}
section.band.deep::before{content:"";position:absolute;inset:0 0 0 55%;z-index:-1;background:url("art/tidal-ocean-1000.webp") right bottom/cover no-repeat;opacity:.28;pointer-events:none}
section.band.deep h2,section.band.deep h3{color:var(--ocean-ink)}
section.band.deep .eyebrow{color:var(--sea-dark)}
section.band.deep a{color:var(--ocean)}
section.band.deep .lead{color:var(--text)}
section.band.deep .btn.ghost{background:#fff;color:var(--ocean);border-color:var(--ocean)}
section.band+section.band{padding-top:0}
section.band.rule{border-top:1px solid var(--line);padding-top:72px}
.section-head{max-width:760px;margin-bottom:48px}
.grid{display:grid;gap:48px 40px}
.grid.c2{grid-template-columns:repeat(2,1fr)}
.grid.c3{grid-template-columns:repeat(3,1fr)}
.grid.c4{grid-template-columns:repeat(4,1fr)}
@media(max-width:900px){.grid.c3,.grid.c4{grid-template-columns:repeat(2,1fr)}}
@media(max-width:600px){.grid.c2,.grid.c3,.grid.c4{grid-template-columns:1fr}.grid{gap:28px}}
.card{background:transparent;border:0;border-top:2px solid var(--sea);border-radius:0;padding:20px 0 0;box-shadow:none;text-decoration:none;color:inherit}
.card h3{margin-top:.1em;font-size:24px}
.card .ic{width:40px;height:40px;border-radius:var(--radius-s);background:var(--sea-soft);display:grid;place-items:center;margin-bottom:16px}
.card .ic svg{width:24px;height:24px}
a.card{display:block}
a.card:hover{border-top-color:var(--ocean)}
a.card:hover h3{color:var(--ocean);text-decoration:underline;text-underline-offset:.2em}
.card p{font-size:16px;color:var(--text)}
.card p:last-child{margin-bottom:0}

/* recognition strip */
.recog{display:grid;grid-template-columns:repeat(4,1fr);gap:0 40px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:transparent;border-radius:0;overflow:visible}
.recog div{padding:22px 0;border-right:0}
.recog b{display:block;color:var(--ocean-ink);font-size:16px}
.recog span{font-size:14px;color:var(--muted);line-height:1.5}
@media(max-width:900px){.recog{grid-template-columns:repeat(2,1fr)}}
@media(max-width:520px){.recog{grid-template-columns:1fr}.recog div{padding:14px 0;border-bottom:1px solid var(--line)}.recog div:last-child{border-bottom:0}}

/* split feature */
.split{display:grid;grid-template-columns:1fr 1fr;gap:64px;align-items:center}
.split.rev>:first-child{order:2}
@media(max-width:860px){.split{grid-template-columns:1fr;gap:32px}.split.rev>:first-child{order:0}}
.figure{margin:0}
.figure img,.figure svg{border-radius:var(--radius);width:100%}
.figure figcaption{font-size:14px;color:var(--muted);margin-top:10px;line-height:1.5}
.figure.framed svg,.figure.framed img{border:1px solid var(--line);background:#fff}

/* technology explorer: text tabs with an underline, panels on white */
.explorer{display:grid;grid-template-columns:260px 1fr;gap:0;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:#fff}
.explorer .tabs{border-right:1px solid var(--line);background:var(--paper);padding:12px;display:flex;flex-direction:column;gap:2px}
.explorer .tabs button{display:flex;gap:12px;align-items:center;width:100%;text-align:left;background:none;border:0;border-left:3px solid transparent;padding:12px 14px;border-radius:0;font:inherit;font-size:15px;color:var(--ocean-ink);cursor:pointer;min-height:44px}
.explorer .tabs button .n{font-family:var(--mono);font-size:12px;color:var(--sea-dark);width:22px}
.explorer .tabs button[aria-selected=true]{border-left-color:var(--ocean);font-weight:700;color:var(--ocean);background:#fff}
.explorer .panel{padding:32px;display:none}
.explorer .panel.active{display:block}
.explorer .panel p{font-size:17px}
.explorer .panel .art{background:var(--paper);border-radius:var(--radius);padding:12px;margin-bottom:20px}
.explorer .panel .art svg{width:100%;height:auto}
.explorer .photo{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:18px}
.explorer .photo figure{margin:0}
.explorer .photo img{border-radius:var(--radius-s);aspect-ratio:4/3;object-fit:cover;width:100%}
.explorer .photo figcaption{font-size:13px;color:var(--muted);margin-top:6px;line-height:1.5}
@media(max-width:860px){.explorer{grid-template-columns:1fr}.explorer .tabs{flex-direction:row;overflow-x:auto;border-right:0;border-bottom:1px solid var(--line);padding:6px}.explorer .tabs button{white-space:nowrap;border-left:0;border-bottom:3px solid transparent}.explorer .tabs button[aria-selected=true]{border-bottom-color:var(--ocean)}.explorer .panel{padding:20px}.explorer .photo{grid-template-columns:1fr}}

/* timeline */
.timeline{position:relative;padding-left:32px;margin:32px 0}
.timeline:before{content:"";position:absolute;left:9px;top:6px;bottom:6px;width:1px;background:var(--line)}
.tl{position:relative;margin-bottom:40px}
.tl:before{content:"";position:absolute;left:-28px;top:8px;width:12px;height:12px;border-radius:50%;background:var(--paper);border:2px solid var(--sea)}
.tl .when{font-family:var(--mono);font-size:13px;color:var(--sea-dark);letter-spacing:.06em}
.tl h3{margin:.2em 0 .3em}
.tl p:last-of-type{margin-bottom:.4em}
.tl .tags{display:flex;gap:6px;flex-wrap:wrap;margin-top:8px}
.tag{font-size:12px;letter-spacing:.04em;padding:4px 9px;border-radius:4px;background:var(--sea-soft);color:var(--sea-dark);border:1px solid var(--line);font-weight:400}
.tag.mat{background:var(--mist);color:var(--ocean-ink)}
.tag.shape{background:var(--sea-soft);color:var(--sea-dark)}

/* journal */
.posts{display:grid;grid-template-columns:repeat(3,1fr);gap:40px}
@media(max-width:900px){.posts{grid-template-columns:repeat(2,1fr)}}
@media(max-width:600px){.posts{grid-template-columns:1fr;gap:32px}}
.post-card{display:flex;flex-direction:column;background:transparent;border:0;border-top:2px solid var(--sea);border-radius:0;overflow:visible;color:inherit;text-decoration:none;padding-top:16px}
.post-card:hover h3{color:var(--ocean);text-decoration:underline;text-underline-offset:.2em}
.post-card .thumb{aspect-ratio:16/10;background:var(--mist);overflow:hidden;border-radius:var(--radius-s)}
.post-card .thumb img,.post-card .thumb svg{width:100%;height:100%;object-fit:cover}
.post-card .thumb.art{background:#fff;padding:10px;border:1px solid var(--line)}.post-card .thumb.art img{object-fit:contain}
.post-card .body{padding:18px 0 0}
.post-card .meta{font-size:12px;color:var(--muted);letter-spacing:.06em;text-transform:uppercase;margin-bottom:8px}
.post-card h3{font-size:22px;margin-bottom:.4em}
.post-card p{font-size:16px;color:var(--text);margin:0}
.filters{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:32px}
.filters button{font:inherit;font-size:14px;padding:9px 14px;min-height:44px;border-radius:var(--radius-s);border:1px solid var(--control);background:#fff;cursor:pointer;color:var(--ocean-ink)}
.filters button[aria-pressed=true]{background:var(--ocean);color:#fff;border-color:var(--ocean)}

/* article heads: kelp fragment in the title area, clipped to the section */
.article-head{position:relative;isolation:isolate;overflow:hidden;padding:72px 0 40px;background:var(--paper)}
.article-head::before{content:"";position:absolute;inset:-60px -80px -60px 58%;z-index:-1;background:url("art/tidal-kelp-1024.webp") center/cover no-repeat;opacity:.42;pointer-events:none}
.article-head::after{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,var(--paper) 0%,var(--paper) 45%,rgba(248,250,247,.6) 62%,rgba(248,250,247,0) 85%);pointer-events:none}
.article-head .meta{font-size:12px;color:var(--sea-dark);letter-spacing:.13em;text-transform:uppercase;font-weight:700;margin-bottom:16px}
.article-head h1{max-width:820px}
.article-head .lead{max-width:720px}
.article-head.compact{padding-bottom:28px}
@media(max-width:860px){.article-head{padding:40px 0 28px}.article-head::before{inset:auto -20px -40px 40%;height:70%;opacity:.26}}
article.prose{max-width:66ch;margin:0 auto;padding:40px 0 48px;font-size:17px}
article.prose h2{font-size:30px;margin-top:2em;line-height:1.2}
article.prose h3{font-size:22px;margin-top:1.6em}
article.prose figure{margin:32px 0}
article.prose figure img,article.prose figure svg{border-radius:var(--radius);width:100%}
article.prose figcaption{font-size:14px;color:var(--muted);margin-top:8px;line-height:1.5}
article.prose blockquote{border-left:2px solid var(--sea);margin:28px 0;padding:4px 0 4px 20px;color:var(--ocean-ink);font-size:19px;font-style:italic}
article.prose ul,article.prose ol{padding-left:1.3em}
article.prose li{margin-bottom:.4em}
.gallery{display:grid;grid-template-columns:repeat(2,1fr);gap:14px;margin:32px 0}
.gallery figure{margin:0}
.gallery img{border-radius:var(--radius-s);width:100%;aspect-ratio:4/3;object-fit:cover}
.gallery.c3{grid-template-columns:repeat(3,1fr)}
@media(max-width:600px){.gallery,.gallery.c3{grid-template-columns:1fr}}
.note{background:#fff;border:1px solid var(--line);border-top:2px solid var(--sea);border-radius:0;padding:18px 22px;font-size:16px;margin:28px 0}
.note.blue{background:#fff;border-color:var(--line);border-top-color:var(--ocean)}
.sources{font-size:14px;color:var(--muted);border-top:1px solid var(--line);padding-top:16px;margin-top:40px}
.sources summary{cursor:pointer;font-weight:700;color:var(--ocean-ink)}
.post-nav{display:flex;justify-content:space-between;gap:16px;max-width:66ch;margin:0 auto;padding:0 0 64px;font-size:15px}

/* stats / facts */
.facts{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.facts div{padding:20px 0;border-top:2px solid var(--sea)}
.facts b{display:block;font-size:30px;color:var(--ocean-ink);font-weight:700;letter-spacing:-.02em;font-variant-numeric:tabular-nums}
.facts span{color:var(--muted);font-size:15px}
@media(max-width:600px){.facts{grid-template-columns:1fr}}

/* definition table */
table.def{width:100%;border-collapse:collapse;font-size:15px;margin:28px 0;background:#fff;font-variant-numeric:tabular-nums}
table.def th,table.def td{text-align:left;padding:14px 16px;border-bottom:1px solid var(--line);vertical-align:top}
table.def th{color:var(--ocean-ink);font-weight:700;width:30%}
table.def thead th{font-size:12px;color:var(--muted);background:var(--mist);letter-spacing:.04em;text-transform:uppercase;width:auto}

/* people */
.people{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.people div{padding:14px 0;border-top:1px solid var(--line)}
.people b{display:block;color:var(--ocean-ink)}
.people span{font-size:15px;color:var(--muted)}
@media(max-width:800px){.people{grid-template-columns:repeat(2,1fr)}}
@media(max-width:500px){.people{grid-template-columns:1fr}}

/* footer: a quiet wash near the close, then paper */
footer.site{position:relative;isolation:isolate;overflow:hidden;background:var(--white);color:var(--text);padding:64px 0 32px;font-size:15px;border-top:1px solid var(--line)}
footer.site::before{content:"";position:absolute;inset:0 0 0 60%;z-index:-1;background:url("art/tidal-ocean-1000.webp") right top/cover no-repeat;opacity:.22;pointer-events:none}
footer.site .cols{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:32px;margin-bottom:40px}
footer.site h4{color:var(--sea-dark);font-size:12px;letter-spacing:.13em;text-transform:uppercase;margin-bottom:14px}
footer.site a{color:var(--ocean-ink);text-decoration:none}
footer.site a:hover{text-decoration:underline}
footer.site ul{list-style:none;margin:0;padding:0}
footer.site li{margin-bottom:10px}
footer.site .legal{border-top:1px solid var(--line);padding-top:20px;font-size:13px;color:var(--muted);display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}
footer.site .brandf img{height:30px;margin-bottom:16px}
footer.site .brandf p{max-width:40ch;font-size:15px}
@media(max-width:800px){footer.site .cols{grid-template-columns:1fr 1fr}}
@media(max-width:500px){footer.site .cols{grid-template-columns:1fr}footer.site::before{opacity:.12}}

/* decorative */
.hexbg{background-image:none}
.skip{position:absolute;left:-999px;top:0;background:#fff;padding:8px}
.skip:focus{left:8px;z-index:100}
.pill-list{display:flex;flex-wrap:wrap;gap:8px;list-style:none;padding:0;margin:16px 0}
.pill-list li{background:#fff;border:1px solid var(--line);border-radius:4px;padding:6px 12px;font-size:15px}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{transition:none!important;animation:none!important}}
@media print{body{background:#fff}.hero::before,.hero::after,.article-head::before,.article-head::after,footer.site::before,section.band.deep::before{display:none}header.site,.preview-band,.burger{display:none}a{color:inherit}}