/* BitcoinII Core. Static, dependency-free, JS-free stylesheet. */
:root{--ink:#202a38;--ink-deep:#0e1b2b;--body:#465366;--sub:#6a7789;--line:#e4eaf0;--paper:#fff;--light:#f6f8fb;--accent:#de841b;--accent-dark:#a95604;--navy:#172b43;--max:1120px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--ink);background:var(--paper);line-height:1.65;font-size:16px;-webkit-font-smoothing:antialiased}a{color:#0d558a;text-decoration:none}a:hover{text-decoration:underline}a:focus-visible{outline:3px solid var(--accent);outline-offset:4px;border-radius:2px}h1,h2,h3,p{margin-top:0}h1,h2,h3{letter-spacing:-.035em;line-height:1.17;color:var(--ink-deep)}h1{font-size:clamp(2.45rem,5vw,4.55rem);font-weight:760}h2{font-size:clamp(1.55rem,2.6vw,2.25rem);font-weight:730}h3{font-size:1.12rem;font-weight:700}p{margin-bottom:1.1rem}img,svg{max-width:100%}.wrap{width:min(var(--max),calc(100% - 48px));margin-inline:auto}.skip-link{position:absolute;top:-60px;left:16px;z-index:50;padding:8px 12px;background:#fff;border:2px solid var(--accent)}.skip-link:focus{top:8px}
.site-header{border-bottom:1px solid var(--line);background:#fff}.header-inner{min-height:94px;display:flex;align-items:center;justify-content:space-between;gap:30px}.brand{display:inline-flex;align-items:center;gap:11px;color:var(--ink-deep);text-decoration:none;white-space:nowrap}.brand:hover{text-decoration:none}.brand-mark{width:49px;height:49px;border-radius:12px;background:var(--accent);display:grid;place-items:center;color:#fff;font-size:29px;font-weight:800;line-height:1;box-shadow:inset 0 0 0 1px #c77712}.brand-name{font-size:24px;font-weight:790;letter-spacing:-.065em}.brand-name>span{color:var(--accent-dark)}.brand-name small{font-size:13px;font-weight:620;letter-spacing:.025em;color:var(--sub);vertical-align:middle}.top-nav{display:flex;flex-wrap:wrap;gap:4px;align-items:center;justify-content:flex-end}.top-nav a{display:inline-block;padding:9px 13px;color:#3d4d61;font-size:14px;font-weight:600;border-radius:5px}.top-nav a:hover{background:#f3f6f9;color:var(--ink-deep);text-decoration:none}.top-nav a[aria-current=page]{background:#fff4e7;color:#864a0b}
.hero{padding-top:78px;padding-bottom:86px;display:grid;grid-template-columns:1.25fr .9fr;align-items:center;gap:65px}.hero-copy{max-width:625px}.eyebrow,.overline,.mini-label{font-size:11px;font-weight:790;letter-spacing:.12em;text-transform:uppercase;color:#7b541e}.eyebrow{display:flex;align-items:center;gap:10px;margin-bottom:22px}.status-dot{width:7px;height:7px;border-radius:100%;background:#c4862a;display:inline-block}.hero h1{margin-bottom:28px;line-height:1.09}.text-accent{color:var(--accent-dark)}.lead{font-size:1.16rem;color:#536174;line-height:1.72}.hero .lead{max-width:600px}.hero-actions{display:flex;gap:11px;align-items:center;flex-wrap:wrap;margin:30px 0 18px}.button{min-height:46px;display:inline-flex;align-items:center;justify-content:center;gap:10px;padding:11px 20px;border-radius:5px;font-size:.91rem;font-weight:700;text-align:center;text-decoration:none;transition:background-color .15s ease,color .15s ease,border-color .15s ease}.button:hover{text-decoration:none}.button-primary{color:white;background:var(--navy);border:1px solid var(--navy)}.button-primary:hover{background:#254463}.button-outline{color:var(--navy);background:#fff;border:1px solid #d0d9e2}.button-outline:hover{background:var(--light);border-color:#aab8c8}.fine-print{font-size:13px;color:var(--sub)}.fine-print a{font-weight:650}.hero-card{padding:25px 29px 25px;background:#f7f9fb;border:1px solid #dfe7ee;border-radius:10px;box-shadow:0 18px 36px -35px rgba(14,27,43,.5)}.hero-card-top{display:flex;align-items:center;justify-content:space-between}.version-pill{border-radius:4px;border:1px solid #e6cfad;padding:4px 9px;font-size:11px;font-weight:760;color:#8b5716;background:#fef5e9}.network-symbol{height:185px;display:grid;place-items:center}.network-symbol span{width:132px;height:132px;display:grid;place-items:center;border-radius:50%;color:#fff;font-size:84px;line-height:1;font-weight:850;background:var(--accent);box-shadow:inset 0 0 0 9px rgba(255,255,255,.12),0 13px 29px -21px #7b551c}.network-kicker{text-align:center;color:#637084;font-size:13px;margin:-2px 0 21px}.network-kicker strong{color:#3b485c}.metrics{display:grid;grid-template-columns:repeat(2,1fr);border-top:1px solid #d8e0e8}.metrics div{padding:15px 8px 12px}.metrics div:nth-child(2n){padding-left:25px}.metrics div:nth-child(n+3){border-top:1px solid #d8e0e8}.metrics strong{display:block;font-size:18px;color:var(--ink-deep);letter-spacing:-.04em;line-height:1.2}.metrics span{display:block;font-size:12px;color:#6d7a8b;margin-top:6px}.rule{border-top:1px solid var(--line)}
.section{padding-block:78px 84px}.section-heading{max-width:770px;margin-bottom:34px}.section-heading h2{margin-bottom:11px}.section-heading>p:last-child{color:var(--body);margin:0}.overline{margin-bottom:14px}.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.feature{display:block;padding:27px;border:1px solid var(--line);border-radius:6px;background:#fff;color:var(--ink);transition:border-color .12s,box-shadow .12s}.feature:hover{text-decoration:none;border-color:#dfbd8f;box-shadow:0 10px 25px -23px #172b43}.feature-flag{color:#997242;font-size:10px;font-weight:780;letter-spacing:.11em}.feature h3{margin:28px 0 9px;font-size:1.16rem}.feature h3 span{float:right;color:#d58b29}.feature p{color:var(--body);font-size:14px;line-height:1.65;margin:0}.band{background:var(--light);border-top:1px solid #eef1f5;border-bottom:1px solid #eef1f5}.split-section{display:grid;grid-template-columns:1fr .83fr;gap:90px;align-items:center;padding-block:76px}.split-section h2{margin-bottom:11px}.split-section p{color:var(--body)}.muted{color:var(--sub)!important;font-size:14px}.text-link{display:inline-block;font-weight:700;font-size:14px}.note-card{background:white;padding:29px 31px;border:1px solid #e4eaf0;border-left:3px solid var(--accent);border-radius:4px}.note-card h3{font-size:1.24rem;margin-bottom:14px}.note-card .note-tag{font-size:10px;letter-spacing:.12em;font-weight:780;color:#986216}.note-card p:not(.note-tag){font-size:14px}.resource-rows{border-top:1px solid var(--line)}.resource-rows>a{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:20px 4px;border-bottom:1px solid var(--line);color:var(--ink)}.resource-rows>a:hover{text-decoration:none;background:#fcfdfd}.resource-rows strong{display:block;font-size:15px}.resource-rows span{display:block;font-size:13px;color:var(--sub);margin-top:3px}.resource-rows b{color:#b5792a;font-size:20px;font-weight:400}.resources-section{padding-top:70px}
.site-footer{background:#fafbfc;border-top:1px solid var(--line)}.footer-top{display:flex;justify-content:space-between;gap:30px;padding-block:44px 27px}.footer-name{font-weight:800;font-size:16px;color:var(--ink-deep)}.footer-top p{font-size:13px;color:var(--sub);margin:8px 0 0;max-width:470px}.footer-links{display:flex;align-items:flex-start;gap:22px;flex-wrap:wrap}.footer-links a{font-size:13px;color:#556376;font-weight:650}.footer-bottom{border-top:1px solid var(--line);padding:18px 0 26px;display:flex;gap:20px;justify-content:space-between;color:#778397;font-size:12px}
.content-shell{padding-block:50px 90px}.narrow{max-width:920px}.breadcrumbs{font-size:12px;color:#7c8897;margin-bottom:58px}.breadcrumbs span{margin:0 10px}.breadcrumbs a{color:#647486}.page-heading{max-width:770px;margin-bottom:43px}.page-heading h1{font-size:clamp(2.25rem,4.1vw,3.5rem);margin-bottom:20px}.page-heading .lead{font-size:1.12rem}.release-highlight{display:flex;align-items:center;justify-content:space-between;gap:30px;background:#f5f7fa;border:1px solid #e1e7ee;border-radius:6px;padding:26px 31px;margin:38px 0 56px}.release-highlight h2{margin:9px 0 8px;font-size:1.65rem}.release-highlight h2 strong{color:var(--accent-dark)}.release-highlight p{font-size:13px;color:var(--sub);margin:0}.subheading{font-size:1.35rem;margin:0 0 23px}.platform-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-bottom:34px}.platform{border:1px solid var(--line);padding:27px 25px 23px;border-radius:6px}.platform-mark{height:50px;font-size:33px;color:#65778a;line-height:1}.platform h3{margin:15px 0 10px}.platform p{color:var(--body);font-size:14px;min-height:71px}.info-panel{border-left:3px solid #c58c39;background:#faf7f1;padding:18px 24px;margin:30px 0 42px}.info-panel h3{font-size:1rem;margin:0 0 9px}.info-panel p{font-size:14px;color:var(--body);margin:0}.two-col{display:grid;grid-template-columns:1fr 1fr;gap:60px}.articles{margin-top:50px}.articles h2{font-size:1.45rem}.articles p{color:var(--body);font-size:15px}.articles pre{background:#f3f5f7;padding:13px 17px;border:1px solid #e5e9ef;border-radius:3px;overflow-x:auto}.articles code,.prose code{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:13px}.prose{max-width:800px}.prose h2{font-size:1.5rem;margin:35px 0 15px}.prose p{color:var(--body);font-size:15.5px;line-height:1.83}.prose strong{color:var(--ink)}.fact-table{width:100%;border-collapse:collapse;max-width:800px;margin:25px 0 37px;text-align:left}.fact-table th,.fact-table td{padding:13px 18px;border-bottom:1px solid var(--line);font-size:14px}.fact-table th{font-weight:650;width:45%;background:#fafbfd}.fact-table td{color:var(--body)}.release-entry{border:1px solid var(--line);border-radius:6px;padding:28px 31px;margin-bottom:24px}.release-entry-top{display:flex;gap:20px;justify-content:space-between;align-items:start}.release-entry h2{font-size:1.55rem;margin:14px 0 9px}.release-badge{font-size:10px;letter-spacing:.1em;color:#a16b1f;font-weight:800}.release-entry p,.release-entry li{font-size:15px;color:var(--body)}.release-entry ul{padding-left:23px;margin:18px 0 0}.release-entry li{padding-bottom:7px}.release-entry.older{background:#fafbfd}.release-entry.older h2{margin-top:0}.compact{margin-top:40px}.error-page{min-height:75vh;display:flex;flex-direction:column;justify-content:center;align-items:start}.error-page h1{font-size:3rem}.error-page p{color:var(--body)}
@media(max-width:970px){.header-inner{align-items:flex-start;padding-block:19px;flex-direction:column;gap:13px}.top-nav{justify-content:flex-start;margin-left:-10px}.top-nav a{padding:5px 10px}.hero{gap:32px;grid-template-columns:1.1fr .9fr;padding-top:54px}.hero h1{font-size:clamp(2.35rem,4.4vw,3.2rem)}.split-section{gap:35px}}
@media(max-width:720px){.wrap{width:min(var(--max),calc(100% - 36px))}.header-inner{padding:16px 0}.brand-mark{width:41px;height:41px;font-size:25px}.brand-name{font-size:22px}.top-nav{width:100%;display:flex;overflow-x:auto;flex-wrap:nowrap;justify-content:flex-start;padding-bottom:3px;white-space:nowrap;scrollbar-width:thin}.top-nav a{font-size:13px;padding:7px 9px}.hero{display:block;padding-top:45px;padding-bottom:56px}.hero-copy{max-width:100%}.hero h1{font-size:clamp(2.5rem,9vw,3.7rem)}.hero .lead{font-size:1.04rem}.hero-card{margin-top:44px;max-width:500px}.section{padding-block:55px}.feature-grid,.platform-grid,.two-col,.split-section{grid-template-columns:1fr}.feature-grid{gap:13px}.feature h3{margin-top:17px}.split-section{gap:23px;padding-block:56px}.content-shell{padding-block:30px 60px}.breadcrumbs{margin-bottom:40px}.page-heading h1{font-size:2.35rem}.release-highlight{display:block;padding:23px}.release-highlight .button{margin-top:20px}.platform-grid{gap:12px}.platform p{min-height:0}.articles{gap:30px}.footer-top,.footer-bottom{display:block}.footer-top{padding-block:32px 20px}.footer-links{margin-top:22px}.footer-bottom span{display:block;margin-bottom:5px}.release-entry-top{display:block}.release-entry-top .button{margin:15px 0 5px}.release-entry{padding:22px}.fact-table th,.fact-table td{padding:12px 10px;font-size:13px}.fact-table th{width:44%}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.button,.feature{transition:none}}

.archive-return{margin-top:2rem}


/* ===== Appearance: follows OS theme, supports saved user light/dark override. =====
   'light-dark' is supported by recent Firefox, Chromium, and Safari versions.
   Original light colors remain the fallback for older browsers. */
:root {
  color-scheme: light dark;
  --ink: light-dark(#202a38, #e9eff7);
  --ink-deep: light-dark(#0e1b2b, #f7f8fb);
  --body: light-dark(#465366, #b9c7da);
  --sub: light-dark(#6a7789, #9aaabd);
  --line: light-dark(#e4eaf0, #324154);
  --paper: light-dark(#fff, #101923);
  --light: light-dark(#f6f8fb, #172433);
  --accent: light-dark(#de841b, #eba03f);
  --accent-dark: light-dark(#a95604, #ffbb70);
  --navy: light-dark(#172b43, #d58835);
}
:root[data-theme="light"] { color-scheme: light; }
:root[data-theme="dark"] { color-scheme: dark; }
a { color: light-dark(#0d558a, #9bcdff); }
.skip-link { background: var(--paper); color:var(--ink); }
.site-header { background:var(--paper); }
.brand-mark { background:none; box-shadow:none; border-radius:12px; overflow:hidden; }
.brand-mark img { display:block; width:100%; height:100%; }
.brand-name>span { color:var(--accent-dark); }
.top-nav a { color:light-dark(#3d4d61, #c9d5e5); }
.top-nav a:hover { background:light-dark(#f3f6f9, #243448); color:var(--ink-deep); }
.top-nav a[aria-current=page] { background:light-dark(#fff4e7, #46321f); color:light-dark(#864a0b, #ffd3a1); }
.theme-toggle { appearance:none; display:inline-flex; align-items:center; justify-content:center; gap:7px; min-height:36px; padding:6px 11px; border-radius:6px; border:1px solid var(--line); background:var(--light); color:var(--ink); font:600 12px/1.2 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif; cursor:pointer; white-space:nowrap; }
.theme-toggle:hover { border-color:var(--accent); background:light-dark(#eef3f9,#26384b); }
.theme-toggle:focus-visible { outline:3px solid var(--accent); outline-offset:3px; }
.theme-glyph { font-size:17px; min-width:17px; }
.eyebrow,.overline,.mini-label { color:light-dark(#7b541e,#f2b769); }
.status-dot { background:light-dark(#c4862a,#f0b15b); }
.lead { color:light-dark(#536174,#c3d0e1); }
.button-primary { color:light-dark(#fff, #151b22); }
.button-primary:hover { background:light-dark(#254463,#f3ad5d); border-color:light-dark(#254463,#f3ad5d); }
.button-outline { color:light-dark(#172b43,#e9eff7); background:var(--paper); border-color:light-dark(#d0d9e2,#4a5a6d); }
.button-outline:hover { background:var(--light); border-color:light-dark(#aab8c8,#8090a3); }
.hero-card { background:light-dark(#f7f9fb,#1b2939); border-color:light-dark(#dfe7ee,#334457); box-shadow:0 18px 36px -35px light-dark(rgba(14,27,43,.5), rgba(0,0,0,.7)); }
.version-pill { border-color:light-dark(#e6cfad,#725639); color:light-dark(#8b5716,#ffd299); background:light-dark(#fef5e9,#46321f); }
.network-symbol img { width:132px; height:132px; object-fit:contain; display:block; filter:drop-shadow(0 12px 14px light-dark(rgba(86,54,10,.13),rgba(0,0,0,.25))); }
.network-kicker { color:light-dark(#637084,#a9b9ce); }
.network-kicker strong { color:light-dark(#3b485c,#e4ecf7); }
.metrics,.metrics div:nth-child(n+3) { border-color:light-dark(#d8e0e8,#3b4b5e); }
.metrics strong { color:var(--ink-deep); }
.metrics span { color:light-dark(#6d7a8b,#a1b2c8); }
.feature { background:light-dark(#fff,#172433); color:var(--ink); }
.feature:hover { border-color:light-dark(#dfbd8f,#aa793a); box-shadow:0 10px 25px -23px light-dark(#172b43,#05090e); }
.feature-flag { color:light-dark(#997242,#f0b973); }
.feature h3 span { color:light-dark(#d58b29,#f0b36a); }
.band { background:var(--light); border-color:light-dark(#eef1f5,#2f3e50); }
.note-card { background:light-dark(#fff,#1c2b3d); border-color:var(--line); border-left-color:var(--accent); }
.note-card .note-tag { color:light-dark(#986216,#f0be7e); }
.resource-rows>a { color:var(--ink); }
.resource-rows>a:hover { background:light-dark(#fcfdfd,#1b2a3b); }
.resource-rows b { color:light-dark(#b5792a,#e6ab58); }
.site-footer { background:light-dark(#fafbfc,#121e2b); }
.footer-name { color:var(--ink-deep); }
.footer-links a { color:light-dark(#556376,#b6c8db); }
.footer-bottom { color:light-dark(#778397,#9aadc1); }
.breadcrumbs { color:light-dark(#7c8897,#a9bacd); }
.breadcrumbs a { color:light-dark(#647486,#b7c8da); }
.release-highlight { background:light-dark(#f5f7fa,#1d2a39); border-color:light-dark(#e1e7ee,#35465a); }
.release-highlight h2 strong { color:var(--accent-dark); }
.platform-mark { color:light-dark(#65778a,#a1b4ca); }
.platform-mark img { display:block; max-width:38px; max-height:38px; }
.info-panel { border-left-color:light-dark(#c58c39,#d39a4b); background:light-dark(#faf7f1,#342a22); }
.articles pre { color:var(--ink); background:light-dark(#f3f5f7,#1a2837); border-color:light-dark(#e5e9ef,#3a4a5c); }
.fact-table th { background:light-dark(#fafbfd,#1d2c3c); }
.release-badge { color:light-dark(#a16b1f,#f2b569); }
.release-entry.older { background:light-dark(#fafbfd,#172433); }
@media (max-width:970px) {
  .theme-toggle { align-self:flex-start; }
}
@media (max-width:720px) {
  .theme-toggle { margin-top:3px; }
}