:root{--paper:#f3f6f1;--tint:#e3ece4;--card:#fbfdfa;--ink:#0d2a1f;--mut:#40594c;--acc:#086b43;--lime:#6fe0ae;--line:rgba(13,42,31,.2);--pmut:#a9c7b8;--ptext:#e3efe7;--serif:"Newsreader",Georgia,"Times New Roman",serif;--sans:"Inter",system-ui,-apple-system,"Segoe UI",sans-serif;--mono:"Cousine","SFMono-Regular",Consolas,"Liberation Mono",monospace}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:96px}
body{margin:0;background:var(--paper);color:var(--ink);font:400 1.03rem/1.62 var(--sans);overflow-x:hidden;-webkit-font-smoothing:antialiased}
[hidden]{display:none!important}
img,svg{max-width:100%}
a{color:var(--acc);text-underline-offset:.18em;text-decoration-thickness:1px}
a:hover{color:var(--ink)}
h1,h2,h3,p,ul,ol,dl,dd,figure{margin:0}
ul,ol{padding:0;list-style:none}
:focus-visible{outline:2px solid var(--acc);outline-offset:3px}
.pine :focus-visible,pre.code :focus-visible,pre.code:focus-visible{outline-color:var(--lime)}
.wrap{max-width:1232px;margin:0 auto;padding:0 32px}
.mono{font-family:var(--mono)}
.skip{position:absolute;left:-9999px;top:0;z-index:99;background:var(--ink);color:#fff;padding:14px 20px}
.skip:focus{left:0}

/* rings */
.rg{display:block;flex:none;overflow:visible}
.rg-c{stroke:currentColor}
.rg-d{fill:var(--acc)}
.pine .rg-d{fill:var(--lime)}

/* header */
.util{border-bottom:1px solid var(--line);font-size:.78rem;color:var(--mut);letter-spacing:.01em}
.util .wrap{display:flex;justify-content:space-between;gap:24px;padding-top:7px;padding-bottom:7px}
.util span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0}
.hd{position:sticky;top:0;z-index:40;background:var(--paper);border-bottom:1px solid var(--ink)}
.hd .wrap{display:flex;align-items:stretch;min-height:68px;position:relative}
.logo{display:inline-flex;align-items:center;gap:11px;color:var(--ink);text-decoration:none;font:500 1.5rem/1 var(--serif);letter-spacing:-.01em;min-height:44px;align-self:center}
.logo .lg{width:26px;height:26px}
.nav{display:flex;margin-left:auto}
.nav a{display:flex;align-items:center;padding:0 16px;color:var(--ink);text-decoration:none;font-size:.94rem;font-weight:500;border-bottom:3px solid transparent;border-top:3px solid transparent;margin-bottom:-1px}
.nav a:hover{border-bottom-color:var(--line)}
.nav a[aria-current]{border-bottom-color:var(--acc)}
.hcta{align-self:center;margin-left:18px}
.burger{display:none;width:44px;height:44px;align-self:center;margin-left:8px;background:none;border:1px solid var(--ink);padding:0;cursor:pointer;position:relative}
.burger span{position:absolute;left:11px;right:11px;height:1.5px;background:var(--ink)}
.burger span:first-child{top:17px}.burger span:last-child{top:25px;right:19px}

/* buttons */
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:0 20px;background:var(--acc);color:#fff;border:1px solid var(--acc);border-radius:0;font:600 .94rem/1.2 var(--sans);text-decoration:none;cursor:pointer;text-align:center;transition:background .15s,color .15s,border-color .15s}
.btn:hover{background:var(--ink);border-color:var(--ink);color:#fff}
.btn.big{min-height:54px;padding:0 30px;font-size:1.02rem}
.btn.sm{padding:0 14px;font-size:.88rem}
.btn.ghost{background:transparent;color:var(--ink);border-color:var(--ink)}
.btn.ghost:hover{background:var(--ink);color:#fff}
.btn[disabled]{opacity:.55;cursor:default}
.pine .btn{background:var(--lime);border-color:var(--lime);color:var(--ink)}
.pine .btn:hover{background:#fff;border-color:#fff;color:var(--ink)}
.lnk{display:inline-flex;align-items:center;min-height:54px;color:var(--ink);font-weight:500;padding:0 4px}

/* bands */
.band{border-top:1px solid var(--line);padding:84px 0;position:relative}
main>.band:first-child{border-top:0}
.tint{background:var(--tint)}
.pine{background:var(--ink);color:var(--ptext);border-top-color:var(--ink)}
.pine a{color:var(--lime)}
.pine+.band{border-top-color:transparent}
.sec{display:grid;grid-template-columns:minmax(0,4fr) minmax(0,8fr);gap:56px;align-items:start}
.sec>*{min-width:0}
.sec-h .mk{width:30px;height:30px;margin-bottom:18px}
h2{font:400 clamp(1.8rem,3vw,2.6rem)/1.08 var(--serif);letter-spacing:-.015em}
h3{font:600 1.06rem/1.35 var(--sans)}
.lbl{font:400 .74rem/1.4 var(--mono);letter-spacing:.14em;text-transform:uppercase;color:var(--mut);margin-bottom:12px}
.lead{font-size:1.2rem;line-height:1.55;color:var(--mut);max-width:60ch}

.rg.dc{width:150px;height:150px;color:var(--mut);margin-top:8px}
/* open frame: the top-right corner is left open */
.open{position:relative;background:linear-gradient(var(--ink),var(--ink)) left top/calc(100% - 44px) 1px no-repeat,linear-gradient(var(--ink),var(--ink)) left top/1px 100% no-repeat,linear-gradient(var(--ink),var(--ink)) left bottom/100% 1px no-repeat,linear-gradient(var(--ink),var(--ink)) right bottom/1px calc(100% - 44px) no-repeat;padding:1px;min-width:0}
.open::after{content:"";position:absolute;top:-3px;right:40px;width:7px;height:7px;border-radius:50%;background:var(--acc)}

/* hero */
.hero{padding:72px 0 92px;overflow:hidden}
.hero .wrap{position:relative}
.art{position:absolute;right:-190px;top:-150px;width:780px;height:780px;max-width:none;color:rgba(13,42,31,.3);pointer-events:none;z-index:0}
.hero .wrap>*:not(.art),.nf .wrap>*:not(.art){position:relative;z-index:1}
.eyebrow{font:400 .8rem/1.4 var(--mono);letter-spacing:.14em;text-transform:uppercase;color:var(--acc);margin-bottom:26px}
h1{font:300 clamp(2.5rem,6.3vw,5.6rem)/1 var(--serif);letter-spacing:-.025em;max-width:17ch;overflow-wrap:break-word}
.hero-g{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:64px;margin-top:56px;align-items:start}
.hero-g>*{min-width:0}
.btns{display:flex;flex-wrap:wrap;align-items:center;gap:10px 26px;margin-top:30px}
.bul{margin-top:36px;border-top:1px solid var(--line)}
.bul li{display:flex;gap:14px;align-items:flex-start;padding:14px 0;border-bottom:1px solid var(--line);font-size:.98rem}
.rg.li{width:15px;height:15px;margin-top:.32em;color:var(--acc)}
.pine .rg.li{color:var(--lime)}
.hero-c .lbl{margin-bottom:14px}

/* code */
.codetabs{display:flex;border-bottom:1px solid var(--line);padding-right:48px;overflow-x:auto}
.codetabs button{min-height:46px;padding:0 20px;background:none;border:0;border-bottom:2px solid transparent;font:400 .84rem/1 var(--mono);color:var(--mut);cursor:pointer;border-radius:0;white-space:nowrap}
.codetabs button[aria-selected="true"]{color:var(--ink);border-bottom-color:var(--acc);font-weight:700}
pre.code{position:relative;margin:0;background:var(--ink);color:#e6f2ea;padding:54px 22px 22px;font:400 .84rem/1.7 var(--mono);overflow-x:auto;max-width:100%;tab-size:2;-webkit-overflow-scrolling:touch}
pre.code code{font:inherit;background:none;padding:0;color:inherit;white-space:pre}
pre.code .k{color:#fff;font-weight:700}
pre.code .s{color:var(--lime)}
pre.code .c{color:#8fb3a1;font-style:italic}
.copy{position:absolute;top:0;right:0;min-height:44px;min-width:72px;padding:0 16px;background:transparent;color:var(--pmut);border:0;border-left:1px solid rgba(227,239,231,.22);border-bottom:1px solid rgba(227,239,231,.22);font:400 .76rem/1 var(--mono);letter-spacing:.08em;text-transform:uppercase;cursor:pointer;border-radius:0}
.copy:hover{color:var(--ink);background:var(--lime)}
.pine pre.code{background:#071a13;border:1px solid rgba(227,239,231,.2)}

/* aperture scale (facts) */
.b-scale{padding:56px 0}
.scale{display:grid;grid-template-columns:repeat(5,minmax(0,1fr))}
.scale li{padding:4px 22px 4px 26px;border-left:1px solid var(--line);min-width:0}
.scale li:first-child{border-left:0;padding-left:0}
.rg.ap{width:54px;height:54px;margin-bottom:20px}
.scale b{display:block;font:300 clamp(1.8rem,3.1vw,2.9rem)/1 var(--serif);letter-spacing:-.02em;overflow-wrap:anywhere}
.scale span{display:block;margin-top:10px;font-size:.86rem;color:var(--mut);line-height:1.4}

/* definitions */
.defs{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 56px}
.def{position:relative;border-top:1px solid var(--line);padding:22px 0 30px 30px;min-width:0}
.def .li{position:absolute;left:0;top:26px;margin:0}
.def p{margin-top:8px;color:var(--mut);font-size:.98rem}
.defs.three{grid-template-columns:1fr}
.defs.three h3{font:400 1.45rem/1.25 var(--serif)}
.defs.three .li{top:31px}

/* steps */
.steps{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:44px}
.steps li{position:relative;border-top:1px solid rgba(227,239,231,.3);padding-top:18px;min-width:0}
.num{display:block;font:300 5.4rem/.95 var(--serif);color:var(--lime);letter-spacing:-.03em}
.rg.st{position:absolute;right:0;top:22px;width:26px;height:26px;color:var(--pmut)}
.steps h3{margin-top:18px;font:400 1.4rem/1.25 var(--serif);color:#fff}
.steps p{margin-top:10px;color:var(--pmut);font-size:.98rem}
.pine h2{color:#fff}

/* rows */
.rows>div{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:36px;padding:24px 0;border-top:1px solid var(--line)}
.rows>div:last-child{border-bottom:1px solid var(--line)}
.rows dt{font:italic 400 1.42rem/1.25 var(--serif)}
.rows dd{color:var(--mut);font-size:.98rem}

/* prose */
.prose{max-width:72ch;min-width:0;overflow-wrap:break-word}
.prose>*:first-child{margin-top:0}
.prose h2{font-size:clamp(1.6rem,2.5vw,2.1rem);margin:56px 0 14px;scroll-margin-top:96px}
.prose h3{font-size:1.14rem;margin:32px 0 8px}
.prose p{margin:0 0 18px}
.prose ul,.prose ol{margin:0 0 20px;padding-left:22px}
.prose ul{list-style:circle}
.prose ol{list-style:decimal}
.prose li{margin-bottom:8px;padding-left:4px}
.prose li::marker{color:var(--acc)}
.prose strong{font-weight:600}
.prose :not(pre)>code,.keyout code{font:400 .88em var(--mono);background:var(--tint);padding:.12em .36em;overflow-wrap:anywhere}
.tint .prose :not(pre)>code{background:var(--card)}
.prose pre.code{margin:24px 0 28px}
.prose table{display:block;max-width:100%;overflow-x:auto;border-collapse:collapse;margin:24px 0 28px;font-size:.94rem;border-top:1px solid var(--ink)}
.prose th,.prose td{padding:12px 18px 12px 0;text-align:left;vertical-align:top;border-bottom:1px solid var(--line);min-width:120px}
.prose th{font:400 .74rem/1.4 var(--mono);letter-spacing:.1em;text-transform:uppercase;color:var(--mut)}
.prose blockquote{margin:24px 0;padding-left:20px;border-left:1px solid var(--ink);font:italic 400 1.3rem/1.45 var(--serif)}
.prose.long{font-size:1.1rem;line-height:1.72;max-width:68ch}

/* faq */
.faq details{border-top:1px solid var(--line)}
.faq details:last-child{border-bottom:1px solid var(--line)}
.faq summary{display:flex;align-items:center;justify-content:space-between;gap:20px;min-height:64px;padding:14px 0;font:400 1.3rem/1.3 var(--serif);cursor:pointer;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"";flex:none;width:18px;height:18px;border:1.5px solid var(--ink);border-radius:50%;border-top-color:transparent;transform:rotate(45deg);transition:transform .2s}
.faq details[open] summary::after{transform:rotate(225deg);border-color:var(--acc);border-top-color:transparent}
.faq details p{padding:0 44px 24px 0;color:var(--mut);max-width:70ch}

/* cta */
.cta{padding:76px 0}
.cta-in{display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:40px;align-items:center}
.rg.big{width:92px;height:92px;color:var(--pmut)}
.cta h2{font-weight:300;font-size:clamp(2rem,4vw,3.3rem)}
.cta p{margin-top:12px;color:var(--pmut);max-width:56ch}

/* page head */
.ph{padding:52px 0 60px}
.ph h1,.key-t h1{font-size:clamp(2.3rem,4.8vw,4.2rem);max-width:20ch}
.ph .lead,.key-t .lead{margin-top:22px}
.crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:0 10px;margin-bottom:18px;font:400 .78rem/1.4 var(--mono);color:var(--mut)}
.crumbs a{display:inline-flex;align-items:center;min-height:44px;color:var(--mut)}
.crumbs i{font-style:normal;color:var(--acc)}
.crumbs span{color:var(--ink)}
.sub{margin-top:20px;font:400 .86rem/1.5 var(--mono);color:var(--acc)}
.meta{margin-top:22px;font:400 .8rem/1.5 var(--mono);letter-spacing:.06em;text-transform:uppercase;color:var(--mut)}
.art-h h1{max-width:24ch;font-size:clamp(2.1rem,4.3vw,3.7rem);line-height:1.04}

/* key + support */
.keytop{padding:48px 0 84px;overflow:hidden}
.key-g{display:grid;grid-template-columns:minmax(0,6fr) minmax(0,5fr);gap:76px;align-items:start}
.key-g>*{min-width:0}
.ben{margin-top:36px;border-bottom:1px solid var(--line)}
.ben li{display:flex;gap:14px;align-items:flex-start;padding:16px 0;border-top:1px solid var(--line)}
.ben p{margin-top:4px;color:var(--mut);font-size:.95rem}
.key-f .open{padding:34px 34px 30px}
.key-t .art.small{position:static;display:block;width:300px;height:300px;margin:48px 0 0 -20px;color:rgba(13,42,31,.4)}
.tabs2{display:flex;gap:26px;border-bottom:1px solid var(--line);margin-bottom:22px}
.tabs2 button{min-height:46px;padding:0;background:none;border:0;border-bottom:2px solid transparent;margin-bottom:-1px;font:500 1rem/1 var(--sans);color:var(--mut);cursor:pointer;border-radius:0}
.tabs2 button[aria-selected="true"]{color:var(--ink);border-bottom-color:var(--acc)}
.msg:empty{display:none}
.msg{margin:0 0 18px;padding:11px 14px;border-left:3px solid var(--acc);background:var(--tint);font-size:.94rem}
.msg.err{border-left-color:#a3261a;color:#7d1a10;background:#f7e9e6}
.row{margin-bottom:16px}
.row label,.calc label{display:block;margin-bottom:7px;font:600 .82rem/1.3 var(--sans);letter-spacing:.01em}
input,select,textarea{width:100%;min-height:48px;padding:10px 14px;background:#fff;color:var(--ink);border:1px solid rgba(13,42,31,.5);border-radius:0;font:400 1rem/1.4 var(--sans);appearance:none;-webkit-appearance:none}
select{background-image:linear-gradient(45deg,transparent 50%,var(--ink) 50%),linear-gradient(135deg,var(--ink) 50%,transparent 50%);background-position:calc(100% - 20px) 21px,calc(100% - 14px) 21px;background-size:6px 6px;background-repeat:no-repeat;padding-right:40px}
textarea{min-height:150px;resize:vertical;display:block}
input:hover,select:hover,textarea:hover{border-color:var(--ink)}
input:focus-visible,select:focus-visible,textarea:focus-visible{outline:2px solid var(--acc);outline-offset:0;border-color:var(--acc)}
.note{margin-top:8px;font-size:.84rem;color:var(--mut);line-height:1.45}
.form .btn.ghost{min-height:50px}
form .btn[type=submit]{width:100%;min-height:54px;font-size:1rem;margin-top:6px}
.keyout{display:none}
.keyout.on{display:block}
.keyout h3{font:400 1.6rem/1.2 var(--serif);margin-bottom:14px}
.keybox{display:flex;align-items:stretch;gap:0;background:var(--ink);color:#e6f2ea}
.keybox span{flex:1;min-width:0;padding:13px 14px;font:400 .86rem/1.5 var(--mono);word-break:break-all}
.keybox .btn{background:var(--lime);border-color:var(--lime);color:var(--ink);flex:none}
.keyout p{margin-top:14px;line-height:1.9;overflow-wrap:anywhere}
.keyout p.note{line-height:1.45;margin-top:10px}
.mut{color:var(--mut)}
.acts{display:flex;flex-wrap:wrap;gap:10px;margin-top:18px}
.sup form{margin-top:0!important}
.sup{padding:34px!important}
.sup [data-support-msg]{min-height:1.4em;font-size:.94rem}

/* calculator */
.calc{display:grid;grid-template-columns:repeat(3,minmax(0,1fr))}
.calc>div{padding:28px 28px 30px;border-left:1px solid var(--line);min-width:0}
.calc>div:first-child{border-left:0}
.calc input{font-family:var(--mono);min-height:52px;font-size:1.02rem}
.calc output{display:block;font:300 clamp(2.2rem,3.6vw,3.2rem)/1.1 var(--serif);color:var(--acc);letter-spacing:-.02em;overflow-wrap:anywhere}

/* docs + article */
.b-doc{padding:64px 0 92px}
.doc-g{display:grid;grid-template-columns:260px minmax(0,1fr);gap:76px;align-items:start}
.art-g{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:76px;align-items:start}
.doc-g>*,.art-g>*{min-width:0}
.rail{position:sticky;top:96px;max-height:calc(100vh - 116px);overflow-y:auto}
.toc ol{border-left:1px solid var(--line)}
.toc a{display:flex;align-items:center;min-height:44px;padding:6px 0 6px 16px;margin-left:-1px;border-left:1px solid transparent;color:var(--mut);text-decoration:none;font-size:.92rem;line-height:1.35}
.toc a:hover{color:var(--ink);border-left-color:var(--ink)}
.side{margin-top:36px;padding-top:22px;border-top:1px solid var(--ink)}
.side-h{font:400 1.4rem/1.2 var(--serif)}
.side p+p{margin-top:8px;color:var(--mut);font-size:.92rem}
.side .btn{margin-top:16px;width:100%}
.take{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 56px}
.take li{display:flex;gap:20px;align-items:flex-start;padding:22px 0;border-top:1px solid var(--line);min-width:0}
.take .ap{width:38px;height:38px;margin:2px 0 0}
.take span{font:400 1.2rem/1.42 var(--serif)}

/* 404 */
.nf{padding:120px 0 140px;overflow:hidden}
.nf .wrap{position:relative}
.nf-l{display:flex;flex-wrap:wrap;gap:0 28px;margin-top:36px}
.nf-l a{display:inline-flex;align-items:center;min-height:44px;color:var(--ink)}

/* footer */
.ft{border-top:1px solid var(--ink);padding:56px 0 36px}
.ft-g{display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap}
.ft-g p{margin-top:10px;color:var(--mut);font-size:.94rem;max-width:36ch}
.ft-n{display:flex;flex-wrap:wrap;gap:0 30px;align-content:flex-start;max-width:560px}
.ft-n a{display:inline-flex;align-items:center;min-height:44px;color:var(--ink);font-size:.94rem;text-decoration:none}
.ft-n a:hover{text-decoration:underline}
.legal{margin-top:40px;padding-top:20px;border-top:1px solid var(--line);font-size:.82rem;color:var(--mut)}

@media (max-width:1040px){
.sec{grid-template-columns:1fr;gap:30px}
.sec-h.deco{display:none}
.hero-g{grid-template-columns:1fr;gap:48px}
.art{right:-300px;top:-220px;opacity:.7}
.key-g{gap:44px}
.doc-g{grid-template-columns:220px minmax(0,1fr);gap:44px}
.art-g{grid-template-columns:minmax(0,1fr) 220px;gap:44px}
.nav a{padding:0 11px}
}
@media (max-width:900px){
.util{display:none}
.wrap{padding:0 20px}
.hd .wrap{min-height:62px}
.burger{display:block}
.hcta{margin-left:auto}
.nav{display:none;position:absolute;left:0;right:0;top:100%;flex-direction:column;background:var(--paper);border-bottom:1px solid var(--ink);margin:1px 0 0;padding:6px 20px 14px}
.nav.open{display:flex}
.nav a{min-height:50px;padding:0;border:0;border-bottom:1px solid var(--line);margin:0;font-size:1.02rem}
.nav a:last-child{border-bottom:0}
.nav a[aria-current]{color:var(--acc)}
.band{padding:60px 0}
.b-scale{padding:36px 0}
.hero{padding:44px 0 60px}
.key-g{display:flex;flex-direction:column;gap:0}
.key-t{display:contents}
.key-t>*{order:0}
.key-f{order:1;width:100%;margin-top:30px}
.key-t .ben{order:2;margin-top:44px;width:100%}
.key-t .art.small{display:none}
.keytop{padding:20px 0 60px}
.doc-g,.art-g{grid-template-columns:1fr;gap:36px}
.rail{position:static;max-height:none}
.art-g .rail{order:-1}
.side{display:none}
.steps{grid-template-columns:1fr;gap:30px}
.num{font-size:4.2rem}
.cta-in{grid-template-columns:1fr;gap:26px}
.rg.big{width:60px;height:60px}
.cta .btn{justify-self:start}
.calc{grid-template-columns:1fr}
.calc>div{border-left:0;border-top:1px solid var(--line);padding:22px}
.calc>div:first-child{border-top:0}
.take{grid-template-columns:1fr}
.ph{padding:26px 0 44px}
}
@media (max-width:700px){
.scale{grid-template-columns:1fr}
.scale li{display:grid;grid-template-columns:44px minmax(0,auto) minmax(0,1fr);gap:0 16px;align-items:center;padding:13px 0;border-left:0;border-top:1px solid var(--line)}
.scale li:first-child{border-top:0}
.rg.ap{width:32px;height:32px;margin:0}
.scale b{font-size:1.75rem}
.scale span{margin:0;text-align:right}
.defs{grid-template-columns:1fr}
.rows>div{grid-template-columns:1fr;gap:8px;padding:20px 0}
.lead{font-size:1.08rem}
.key-f .open,.sup{padding:24px 20px!important}
.art{width:560px;height:560px;right:-330px;top:-200px}
.btns .btn{flex:1 1 100%}
.lnk{min-height:44px}
.faq summary{font-size:1.16rem}
.faq details p{padding-right:0}
.prose.long{font-size:1.04rem}
.ft-g{flex-direction:column;gap:24px}
}
@media (max-width:400px){
.wrap{padding:0 16px}
.nav{padding-left:16px;padding-right:16px}
.logo{font-size:1.3rem;gap:8px}
.logo .lg{width:22px;height:22px}
.hcta{padding:0 12px;font-size:.86rem}
h1{font-size:2.3rem}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}html{scroll-behavior:auto}}