/* 2FA Keyring website.
   Layout: a left-aligned editorial column with one live "device" panel in the hero;
   sections alternate between the page ground and a slightly deeper band. */
:root{
  color-scheme:light;
  --paper:#F6F7F9; --band:#EAEEF3; --surface:#FFFFFF;
  --ink:#111B26; --muted:#556375; --line:#D3DAE2;
  --accent:#2C4BD6; --accent-ink:#FFFFFF; --accent-soft:#E2E7FB;
  --ok:#17744A; --ok-soft:#DDF1E6; --danger:#B42318; --danger-soft:#FBE4E1; --warn:#B8470F;
  --code-bg:#111B26; --code-ink:#DCE4EE; --code-key:#9DB1FF; --code-val:#8FE0B5;
  --font-display:"Bricolage Grotesque",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-body:"Bricolage Grotesque",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-code:"JetBrains Mono",ui-monospace,"SF Mono",Menlo,Consolas,monospace;
  --wrap:1120px;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --paper:#0E141B; --band:#121A23; --surface:#151D26;
    --ink:#E7ECF2; --muted:#95A3B4; --line:#27333F;
    --accent:#8AA2FF; --accent-ink:#0E141B; --accent-soft:#1D2644;
    --ok:#5FD49A; --ok-soft:#12291F; --danger:#FF8A80; --danger-soft:#2E1716; --warn:#FF9A5C;
    --code-bg:#080C11; --code-ink:#DCE4EE; --code-key:#9DB1FF; --code-val:#8FE0B5;
    color-scheme:dark;
  }
}
:root[data-theme="dark"]{
  --paper:#0E141B; --band:#121A23; --surface:#151D26;
  --ink:#E7ECF2; --muted:#95A3B4; --line:#27333F;
  --accent:#8AA2FF; --accent-ink:#0E141B; --accent-soft:#1D2644;
  --ok:#5FD49A; --ok-soft:#12291F; --danger:#FF8A80; --danger-soft:#2E1716; --warn:#FF9A5C;
  --code-bg:#080C11; --code-ink:#DCE4EE; --code-key:#9DB1FF; --code-val:#8FE0B5;
  color-scheme:dark;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--paper);color:var(--ink);
  font:16px/1.6 var(--font-body);font-optical-sizing:auto;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,p,ul,ol,dl,dd,figure{margin:0}
ul,ol{padding:0;list-style:none}
h1,h2,h3{font-family:var(--font-display);line-height:1.1;text-wrap:balance}
a{color:var(--accent)}
img,svg{max-width:100%}
code,kbd{font-family:var(--font-code);font-size:.88em}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px}

.wrap{
  max-width:var(--wrap);margin-inline:auto;
  padding-left:max(20px,env(safe-area-inset-left,0px));
  padding-right:max(20px,env(safe-area-inset-right,0px));
}
.band{background:var(--band);border-block:1px solid var(--line)}
section.block{padding-block:clamp(56px,9vw,104px)}
.kicker{font:600 12px/1.2 var(--font-code);letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}
.h2{font-size:clamp(28px,4vw,42px);font-weight:700;letter-spacing:-.015em}
.lead{font-size:clamp(17px,1.6vw,19px);color:var(--muted);max-width:62ch}
.sec-head{display:grid;gap:14px;margin-bottom:clamp(32px,5vw,52px);max-width:760px}
.muted{color:var(--muted)}
.nowrap{white-space:nowrap}

/* buttons */
.btn{
  display:inline-flex;align-items:center;gap:8px;min-height:46px;padding:10px 20px;border-radius:10px;
  font:650 16px/1 var(--font-body);text-decoration:none;border:1px solid var(--line);color:var(--ink);background:var(--surface);
  transition:transform .12s,filter .12s,border-color .12s;
}
.btn:hover{border-color:var(--muted)}
.btn:active{transform:translateY(1px)}
.btn.primary{background:var(--accent);border-color:var(--accent);color:var(--accent-ink)}
.btn.primary:hover{filter:brightness(1.08)}
.btn.small{min-height:38px;padding:8px 14px;font-size:14px}
.btns{display:flex;flex-wrap:wrap;gap:12px}


/* hero */
.hero{padding-block:clamp(40px,7vw,88px) clamp(48px,8vw,96px)}
.hero .wrap{display:grid;grid-template-columns:minmax(0,1.08fr) minmax(0,.92fr);gap:clamp(32px,6vw,72px);align-items:center}
.hero-copy{display:grid;gap:22px;min-width:0}
.hero h1{font-size:clamp(40px,6.4vw,72px);font-weight:750;letter-spacing:-.03em;line-height:1.02;font-stretch:92%}
.hero h1 em{font-style:normal;color:var(--accent)}
.hero .lead{max-width:52ch}
.facts{display:flex;flex-wrap:wrap;gap:8px}
.fact{display:inline-flex;align-items:center;gap:6px;padding:5px 10px;border:1px solid var(--line);border-radius:999px;font:500 13px/1.2 var(--font-code);color:var(--muted);background:var(--surface)}
.fact::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--ok)}
.works{font-size:14px;color:var(--muted)}

/* device panel */
.device{
  background:var(--surface);border:1px solid var(--line);border-radius:18px;overflow:hidden;min-width:0;
  box-shadow:0 1px 0 var(--line),0 24px 48px -28px rgba(17,27,38,.35);
}
.device-bar{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px 18px;border-bottom:1px solid var(--line)}
.device-bar strong{font:700 15px/1 var(--font-display)}
.lockchip{display:inline-flex;align-items:center;gap:6px;font:600 12px/1 var(--font-code);color:var(--ok);background:var(--ok-soft);padding:6px 9px;border-radius:999px}
.demo-row{display:grid;grid-template-columns:40px minmax(0,1fr) auto 40px;gap:12px;align-items:center;padding:14px 18px;border-top:1px solid var(--line)}
.demo-row:first-child{border-top:0}
.mono{display:grid;place-items:center;width:40px;height:40px;border-radius:10px;font:700 16px/1 var(--font-display);background:var(--accent-soft);color:var(--accent)}
.demo-who{display:grid;min-width:0}
.demo-who b{font-weight:650;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.demo-who span{font:12px/1.4 var(--font-code);color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.digits{font:600 clamp(22px,2.6vw,28px)/1 var(--font-code);letter-spacing:.04em;font-variant-numeric:tabular-nums;text-align:right}
.ring{position:relative;display:grid;place-items:center;width:40px;height:40px}
.ring svg{width:100%;height:100%;transform:rotate(-90deg)}
.ring circle{fill:none;stroke-width:3}
.ring .trk{stroke:var(--line)}
.ring .arc{stroke:var(--accent);stroke-linecap:round;stroke-dasharray:94.25;transition:stroke-dashoffset .25s linear}
.ring .sec{position:absolute;font:600 11px/1 var(--font-code);color:var(--muted);font-variant-numeric:tabular-nums}
.demo-row.urgent .arc{stroke:var(--warn)}
.demo-row.urgent .digits{color:var(--warn)}
.device-foot{padding:12px 18px;border-top:1px solid var(--line);font-size:13px;color:var(--muted);background:var(--band)}
@media (max-width:860px){.hero .wrap{grid-template-columns:minmax(0,1fr)}}
@media (max-width:420px){.demo-row{grid-template-columns:36px minmax(0,1fr) auto;padding:12px 14px}.demo-row .ring{display:none}.mono{width:36px;height:36px}}

/* flow diagram */
.flow{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0;counter-reset:none}
.flow li{position:relative;display:grid;gap:8px;align-content:start;padding:20px 22px 22px;border:1px solid var(--line);background:var(--surface);min-width:0}
.flow li+li{border-left:0}
.flow li:first-child{border-radius:14px 0 0 14px}
.flow li:last-child{border-radius:0 14px 14px 0}
.flow li+li::before{
  content:"";position:absolute;left:-9px;top:28px;width:16px;height:16px;background:var(--surface);
  border-top:1px solid var(--line);border-right:1px solid var(--line);transform:rotate(45deg);
}
.flow .tag{font:600 12px/1.2 var(--font-code);letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.flow b{font:700 19px/1.2 var(--font-display)}
.flow p{font-size:14px;color:var(--muted)}
.flow code{color:var(--ink)}
@media (max-width:860px){
  .flow{grid-template-columns:minmax(0,1fr)}
  .flow li+li{border-left:1px solid var(--line);border-top:0}
  .flow li:first-child{border-radius:14px 14px 0 0}
  .flow li:last-child{border-radius:0 0 14px 14px}
  .flow li+li::before{left:28px;top:-9px;transform:rotate(135deg)}
}
.nonet{margin-top:20px;display:grid;grid-template-columns:auto minmax(0,1fr);gap:14px;align-items:start;padding:18px 20px;border:1px solid var(--ok);border-radius:14px;background:var(--ok-soft)}
.nonet .x{display:grid;place-items:center;width:36px;height:36px;border-radius:50%;background:var(--ok);color:var(--paper)}
.nonet b{display:block;font:700 17px/1.3 var(--font-display);margin-bottom:2px}
.nonet p{font-size:15px;color:var(--ink)}

/* code block */
.policy{margin-top:28px;display:grid;gap:10px;min-width:0}
.policy .cap{font-size:14px;color:var(--muted)}
pre.code{
  margin:0;padding:18px 20px;border-radius:12px;background:var(--code-bg);color:var(--code-ink);
  font:13.5px/1.7 var(--font-code);overflow-x:auto;white-space:pre;
}
pre.code .k{color:var(--code-key)}
pre.code .v{color:var(--code-val)}

/* protects / doesn't */
.two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}
.col{display:grid;gap:4px;align-content:start;padding:24px;border-radius:14px;border:1px solid var(--line);background:var(--surface);min-width:0}
.col h3{font-size:20px;display:flex;align-items:center;gap:10px;margin-bottom:8px}
.col h3 .dot{width:10px;height:10px;border-radius:50%;flex:none}
.col.yes h3 .dot{background:var(--ok)}
.col.no h3 .dot{background:var(--danger)}
.col li{padding:12px 0;border-top:1px solid var(--line);display:grid;gap:2px}
.col li b{font-weight:650}
.col li span{font-size:15px;color:var(--muted)}
@media (max-width:760px){.two{grid-template-columns:minmax(0,1fr)}}

/* steps */
.steps{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(20px,3vw,40px);counter-reset:step}
.steps li{display:grid;gap:10px;align-content:start;counter-increment:step;padding-top:18px;border-top:2px solid var(--ink)}
.steps li::before{content:"Step " counter(step);font:600 12px/1 var(--font-code);letter-spacing:.1em;text-transform:uppercase;color:var(--accent)}
.steps h3{font-size:22px}
.steps p{color:var(--muted)}
@media (max-width:760px){.steps{grid-template-columns:minmax(0,1fr)}}

/* features */
.features{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:0 clamp(24px,4vw,48px)}
.features div{padding-block:20px;border-top:1px solid var(--line);display:grid;gap:6px;align-content:start}
.features dt{font:700 18px/1.3 var(--font-display)}
.features dd{color:var(--muted);font-size:15px}
@media (max-width:860px){.features{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media (max-width:560px){.features{grid-template-columns:minmax(0,1fr)}}

/* faq */
.faq{display:grid;max-width:820px;border-top:1px solid var(--line)}
.faq details{border-bottom:1px solid var(--line)}
.faq summary{
  list-style:none;cursor:pointer;display:flex;justify-content:space-between;gap:16px;align-items:center;
  padding:18px 0;font:650 18px/1.35 var(--font-display);
}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";font:400 26px/1 var(--font-code);color:var(--muted);flex:none;transition:transform .2s}
.faq details[open] summary::after{transform:rotate(45deg)}
.faq .ans{padding:0 0 20px;color:var(--muted);max-width:68ch;display:grid;gap:10px}

/* closing band */
.closing .wrap{display:flex;justify-content:space-between;align-items:center;gap:24px;flex-wrap:wrap}
.closing h2{max-width:20ch}


/* ---------- security document ---------- */
.doc-hero{padding-block:clamp(40px,6vw,72px) clamp(28px,4vw,40px);border-bottom:1px solid var(--line)}
.doc-hero h1{font-size:clamp(36px,5.4vw,58px);font-weight:750;letter-spacing:-.025em;margin-block:12px 16px}
.doc-hero .meta{margin-top:16px;font:13px/1.5 var(--font-code);color:var(--muted)}
.doc{display:grid;grid-template-columns:220px minmax(0,1fr);gap:clamp(32px,5vw,64px);padding-block:clamp(32px,5vw,56px) 80px}
.toc{position:sticky;top:24px;align-self:start;display:grid;gap:2px;font-size:14px}
.toc p{font:600 12px/1 var(--font-code);letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin-bottom:10px}
.toc a{color:var(--muted);text-decoration:none;padding:5px 0 5px 12px;border-left:2px solid var(--line)}
.toc a:hover{color:var(--ink);border-left-color:var(--accent)}
.prose{max-width:72ch;display:grid;gap:18px;min-width:0}
.prose h2{font-size:clamp(24px,3vw,30px);font-weight:700;letter-spacing:-.01em;margin-top:28px;scroll-margin-top:24px}
.prose h2:first-child{margin-top:0}
.prose h3{font-size:19px;margin-top:8px}
.prose ul{display:grid;gap:8px;padding-left:20px;list-style:disc}
.prose ol{display:grid;gap:8px;padding-left:22px;list-style:decimal}
.prose li::marker{color:var(--muted)}
.prose code{background:var(--band);border:1px solid var(--line);border-radius:5px;padding:1px 5px}
.prose pre.code code{background:none;border:0;padding:0}
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:12px;background:var(--surface)}
table{border-collapse:collapse;width:100%;font-size:15px;min-width:520px}
th,td{text-align:left;vertical-align:top;padding:12px 16px;border-top:1px solid var(--line)}
thead th{border-top:0;font:600 12px/1.3 var(--font-code);letter-spacing:.08em;text-transform:uppercase;color:var(--muted);background:var(--band)}
td:first-child{font-weight:650;white-space:nowrap}
td code{font-size:.85em}
.callout{padding:16px 18px;border-radius:12px;border:1px solid var(--line);background:var(--surface);display:grid;gap:6px}
.callout.warn{border-color:var(--warn)}
.callout b{font-family:var(--font-display);font-size:17px}
@media (max-width:860px){.doc{grid-template-columns:minmax(0,1fr)}.toc{position:static}}

@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}html{scroll-behavior:auto}}