/* Arc555: holding page and privacy notice. Inter is self-hosted in ../fonts. */
@font-face{
  font-family:"Inter";font-style:normal;font-weight:100 900;font-display:swap;
  src:url("../fonts/inter-latin.woff2") format("woff2");
  unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}
@font-face{
  font-family:"Inter";font-style:normal;font-weight:100 900;font-display:swap;
  src:url("../fonts/inter-latin-ext.woff2") format("woff2");
  unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF;
}
:root{
  --ink:#1A1A1A; --yellow:#F8F15F; --white:#FFFFFF;
  --grey-95:#F4F5F6; --grey-70:#C2C7CD; --grey-60:#A9AFB6; --grey-50:#8E949B; --grey-40:#71777E; --grey-20:#34373C;
  --surface:#FFFFFF; --impact:#1A1A1A; --border:#D7DBE0; --border-dark:#2C3036;
  --fg:#1A1A1A; --fg-muted:#6B7075; --fg-inverse:#FFFFFF; --fg-inverse-muted:#9197A0;
  --wrap:820px; --gutter:clamp(20px,5vw,24px);
  --fs-h1:44px; --fs-h2:30px; --fs-body:16px; --lh-body:24px;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{margin:0;font-family:Inter,ui-sans-serif,system-ui,sans-serif;color:var(--fg);background:var(--surface);font-size:var(--fs-body);line-height:var(--lh-body);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
h1,h2{font-weight:700;letter-spacing:-0.03em;line-height:1.05;margin:0;text-wrap:pretty}
p{margin:0 0 16px}
strong{font-weight:600}
a{color:var(--fg);text-decoration:underline;text-decoration-color:var(--grey-70);text-underline-offset:3px;text-decoration-thickness:1px}
a:hover{text-decoration-color:var(--yellow);text-decoration-thickness:2px}
a:focus-visible{outline:2px solid var(--ink);outline-offset:3px}
::selection{background:var(--yellow);color:var(--ink)}
.skip-link{position:absolute;left:-9999px;top:0;background:var(--yellow);color:var(--ink);padding:10px 18px;font-weight:600;z-index:999;text-decoration:none}
.skip-link:focus{left:0}
.wrap{max-width:var(--wrap);margin:0 auto;padding-left:var(--gutter);padding-right:var(--gutter)}

.band{background:var(--impact);color:var(--fg-inverse);padding:clamp(28px,4vw,40px) 0 clamp(40px,5vw,56px)}
.band .logo{display:inline-block;height:40px;margin-bottom:clamp(40px,6vw,64px);text-decoration:none}
.band .logo img{height:40px;width:auto;display:block}
.band .logo:focus-visible{outline:2px solid var(--yellow);outline-offset:6px}
.band h1{font-size:var(--fs-h1);color:var(--white);margin-bottom:14px}
.band .sub{color:var(--fg-inverse-muted);font-size:16px;margin-bottom:4px}
.band .upd{color:var(--grey-50);font-size:14px;margin:0}

main{padding-top:clamp(40px,6vw,56px);padding-bottom:clamp(64px,8vw,96px)}

.toc{background:var(--grey-95);border:1px solid var(--border);border-left:4px solid var(--yellow);padding:clamp(20px,3vw,28px) clamp(20px,3.5vw,32px) clamp(22px,3vw,30px)}
.toc h2{font-size:var(--fs-h2);margin-bottom:18px}
.toc ol{margin:0;padding:0;list-style:none;counter-reset:toc}
.toc li{counter-increment:toc;display:flex;gap:12px;margin:0 0 8px}
.toc li::before{content:counter(toc) ".";color:var(--fg-muted);font-weight:600;min-width:28px;font-variant-numeric:tabular-nums}
.toc li:last-child{margin-bottom:0}

.sec{margin-top:clamp(44px,6vw,60px)}
.sec h2{font-size:var(--fs-h2);line-height:1.15;margin-bottom:16px;scroll-margin-top:24px;display:flex;gap:14px}
.sec h2 .num{color:var(--fg-muted);font-weight:600;font-variant-numeric:tabular-nums;flex:none}
.sec p{color:var(--grey-20)}
.sec p:last-child{margin-bottom:0}

.footer{background:var(--impact);color:var(--fg-inverse);border-top:1px solid var(--border-dark);padding:24px 0 28px}
.footer p{color:var(--grey-40);font-size:12px;line-height:1.7;margin:0}
.footer p+p{margin-top:4px}
.footer a{color:var(--grey-40)}
.footer a:hover{color:var(--white)}

@media (max-width:600px){
  :root{--fs-h1:34px;--fs-h2:24px}
  .sec h2{gap:10px}
}
@media print{
  .band,.footer{-webkit-print-color-adjust:exact;print-color-adjust:exact}
  .skip-link{display:none}
  .sec{break-inside:avoid-page}
  a{text-decoration:none}
}

/* Holding page (index.html): follows the visitor's colour scheme, or the theme button */
.home{--page-bg:#FFFFFF;--page-fg:#1A1A1A;--page-muted:#6B7075;--page-border:#D7DBE0;color-scheme:light}
:root[data-theme="dark"] .home{--page-bg:#1A1A1A;--page-fg:#FFFFFF;--page-muted:#9197A0;--page-border:#2C3036;color-scheme:dark}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]) .home{--page-bg:#1A1A1A;--page-fg:#FFFFFF;--page-muted:#9197A0;--page-border:#2C3036;color-scheme:dark}
}
.home{background:var(--page-bg);color:var(--page-fg);min-height:100vh;min-height:100svh;display:flex;flex-direction:column}
.home main{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:clamp(40px,8vw,96px) var(--gutter)}
.home .mark{margin:0;line-height:0}
.home .mark img{width:clamp(200px,38vw,280px);height:auto}
.home .mark .logo-on-light{display:block}
.home .mark .logo-on-dark{display:none}
:root[data-theme="dark"] .home .mark .logo-on-light{display:none}
:root[data-theme="dark"] .home .mark .logo-on-dark{display:block}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]) .home .mark .logo-on-light{display:none}
  :root:not([data-theme="light"]) .home .mark .logo-on-dark{display:block}
}
.home .tagline{margin:36px 0 0;color:var(--page-muted);font-size:clamp(16px,2vw,18px)}
.theme-toggle{position:fixed;top:16px;right:16px;min-height:40px;padding:8px 14px;border:1px solid var(--page-border);border-radius:0;background:var(--page-bg);color:var(--page-fg);font:500 13px/1 Inter,ui-sans-serif,system-ui,sans-serif;cursor:pointer}
.theme-toggle:hover{border-color:var(--page-fg)}
.theme-toggle:focus-visible{outline:2px solid var(--yellow);outline-offset:3px}
.theme-toggle[hidden]{display:none}