/* EBIURO24 Mail AI - public website. One file, system fonts, no external resources. */
:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --bg-alt: #f2f6fc;
  --surface: #ffffff;
  --text: #14202f;
  --muted: #46566b;
  --brand: #0b3a8f;
  --link: #0b3a8f;
  --link-hover: #082a6a;
  --border: #d3dcea;
  --btn-bg: #0b3a8f;
  --btn-bg-hover: #082a6a;
  --btn-text: #ffffff;
  --mark-bg: #0b3a8f;
  --hero-from: #e6eefb;
  --callout-bg: #eef4ff;
  --callout-border: #9db9ea;
  --warn-bg: #fff7e0;
  --warn-border: #d9a93e;
  --code-bg: #eaf0f8;
  --focus: #b45f00;
  --chip-red: #b42318;
  --chip-blue: #0b3a8f;
  --chip-green: #0d6b45;
  --chip-purple: #66399c;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1420;
    --bg-alt: #111b2b;
    --surface: #16233a;
    --text: #e6edf7;
    --muted: #a9b7cb;
    --brand: #8db4ff;
    --link: #8db4ff;
    --link-hover: #bcd2ff;
    --border: #2a3a55;
    --btn-bg: #9cc2ff;
    --btn-bg-hover: #bcd5ff;
    --btn-text: #06142e;
    --mark-bg: #3a6fe0;
    --hero-from: #13233f;
    --callout-bg: #13233f;
    --callout-border: #35558f;
    --warn-bg: #2b2412;
    --warn-border: #8a6d1f;
    --code-bg: #101b2e;
    --focus: #ffb84d;
  }
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-padding-top: 1rem; }
body { margin: 0; background: var(--bg); color: var(--text); font: 1rem/1.65 var(--font); }
img, svg { max-width: 100%; height: auto; }
a { color: var(--link); text-underline-offset: 0.15em; }
a:hover { color: var(--link-hover); }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; border-radius: 4px; }
main:focus { outline: none; }
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.skip-link { position: absolute; left: 0.5rem; top: -4rem; z-index: 10; background: var(--btn-bg); color: var(--btn-text); padding: 0.6rem 1rem; border-radius: 0 0 8px 8px; }
.skip-link:focus { top: 0; color: var(--btn-text); }
.wrap { width: 100%; max-width: 70rem; margin-inline: auto; padding-inline: 1rem; }

/* header */
.site-header { border-bottom: 1px solid var(--border); background: var(--bg); }
.bar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.5rem 1.25rem; padding-block: 0.7rem; }
.brand { display: inline-flex; align-items: center; gap: 0.6rem; color: var(--text); text-decoration: none; font-size: 1.1rem; }
.brand:hover { color: var(--text); }
.brand b { color: var(--brand); }
.mark-bg { fill: var(--mark-bg); }
.mark-fg { fill: #ffffff; }
.mark-line { stroke: var(--mark-bg); }
.nav ul { display: flex; flex-wrap: wrap; align-items: center; gap: 0.15rem 0.35rem; list-style: none; margin: 0; padding: 0; }
.nav a:not(.btn) { display: inline-block; padding: 0.4rem 0.65rem; border-radius: 8px; color: var(--text); text-decoration: none; font-weight: 500; }
.nav a:not(.btn):hover { background: var(--bg-alt); }
.nav a[aria-current="page"]:not(.btn) { color: var(--brand); text-decoration: underline; text-underline-offset: 0.35em; text-decoration-thickness: 2px; }

/* buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem; padding: 0.7rem 1.2rem; border: 2px solid var(--btn-bg); border-radius: 10px; background: var(--btn-bg); color: var(--btn-text); font: inherit; font-weight: 600; line-height: 1.25; text-align: center; text-decoration: none; transition: background-color 0.15s, color 0.15s; }
.btn:hover { background: var(--btn-bg-hover); border-color: var(--btn-bg-hover); color: var(--btn-text); }
.btn-secondary { background: transparent; color: var(--brand); }
.btn-secondary:hover { background: var(--bg-alt); color: var(--link-hover); border-color: var(--brand); }
.btn-sm { padding: 0.4rem 0.9rem; border-radius: 8px; }
.btn-lg { padding: 0.9rem 1.5rem; font-size: 1.1rem; }
.ico { width: 1.5rem; height: 1.5rem; flex: none; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

/* typography */
h1, h2, h3 { line-height: 1.25; margin: 0 0 0.6em; }
h1 { font-size: clamp(1.75rem, 1.2rem + 2.6vw, 2.6rem); letter-spacing: -0.01em; }
h2 { font-size: clamp(1.4rem, 1.15rem + 1.1vw, 1.85rem); margin-top: 2.2rem; }
h3 { font-size: 1.15rem; margin-top: 1.6rem; }
p, ul, ol, dl, pre, table { margin: 0 0 1rem; }
ul, ol { padding-left: 1.4rem; }
li { margin-bottom: 0.35rem; }
strong { font-weight: 650; }
code, pre { font-family: var(--mono); font-size: 0.9em; }
code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 5px; }
pre { background: var(--code-bg); padding: 0.85rem 1rem; border-radius: 10px; overflow-x: auto; }
pre code { background: none; padding: 0; }
.prose { max-width: 47rem; padding-block: 1.5rem 3rem; }
.prose > :first-child, .section > .wrap > :first-child { margin-top: 0; }
.lead { font-size: 1.15rem; color: var(--muted); }
.meta { color: var(--muted); font-size: 0.92rem; }
.eyebrow { margin: 0 0 0.5rem; color: var(--brand); font-weight: 650; font-size: 0.92rem; letter-spacing: 0.04em; text-transform: uppercase; }
.note { color: var(--muted); font-size: 0.95rem; }

/* breadcrumbs */
.crumbs { padding-block: 0.9rem 0; font-size: 0.92rem; }
.crumbs ol { display: flex; flex-wrap: wrap; gap: 0.2rem 0.45rem; list-style: none; margin: 0; padding: 0; color: var(--muted); }
.crumbs li { margin: 0; }
.crumbs li + li::before { content: "/"; margin-right: 0.45rem; color: var(--muted); }

/* hero */
.hero { background: linear-gradient(180deg, var(--hero-from), var(--bg)); padding-block: 2rem 2.5rem; }
.hero-grid { display: grid; gap: 2rem; align-items: center; }
.hero h1 { margin-bottom: 0.5em; }
.cta-row { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-block: 1.5rem 1rem; }
.facts { display: flex; flex-wrap: wrap; gap: 0.4rem 1.25rem; list-style: none; margin: 0; padding: 0; color: var(--muted); font-size: 0.95rem; }
.facts li { margin: 0; }
.facts li::before { content: "\2713"; margin-right: 0.4rem; color: var(--brand); font-weight: 700; }
.hero-art { margin: 0; }
.hero-art svg { display: block; width: 100%; height: auto; }

/* sections and cards */
.section { padding-block: 2.5rem; }
.section-alt { background: var(--bg-alt); }
.section h2:first-child { margin-top: 0; }
.cards { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(17.5rem, 1fr)); margin-top: 1.25rem; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; padding: 1.15rem 1.2rem; }
.card h3 { display: flex; align-items: center; gap: 0.55rem; margin: 0 0 0.5rem; font-size: 1.1rem; }
.card h3 .ico { color: var(--brand); }
.card p:last-child { margin-bottom: 0; }
.two-col { display: grid; gap: 1.5rem; }
.checks { list-style: none; padding: 0; }
.checks li { position: relative; padding-left: 1.7rem; }
.checks li::before { content: "\2713"; position: absolute; left: 0; color: var(--brand); font-weight: 700; }

/* steps */
.steps { counter-reset: step; list-style: none; padding: 0; }
.steps > li { counter-increment: step; position: relative; margin: 0 0 0.7rem; padding: 0.85rem 1rem 0.85rem 3.4rem; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; }
.steps > li::before { content: counter(step); position: absolute; left: 0.9rem; top: 0.8rem; display: grid; place-items: center; width: 1.9rem; height: 1.9rem; border-radius: 50%; background: var(--btn-bg); color: var(--btn-text); font-weight: 700; }
.steps > li > :last-child { margin-bottom: 0; }

/* callouts, spec list, tables, faq */
.callout { background: var(--callout-bg); border: 1px solid var(--callout-border); border-left-width: 5px; border-radius: 10px; padding: 0.9rem 1.1rem; margin-block: 1.25rem; }
.callout > :last-child { margin-bottom: 0; }
.callout h2, .callout h3 { margin-top: 0; }
.callout-warn { background: var(--warn-bg); border-color: var(--warn-border); }
.download-box { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; padding: 1.25rem; margin-block: 1.25rem; }
.download-box h2 { margin-top: 0; }
.spec { display: grid; gap: 0.1rem 1.25rem; grid-template-columns: 1fr; margin-bottom: 1.25rem; }
.spec dt { color: var(--muted); font-weight: 600; margin-top: 0.6rem; }
.spec dd { margin: 0; overflow-wrap: anywhere; }
.hash { font-family: var(--mono); font-size: 0.88em; word-break: break-all; background: var(--code-bg); padding: 0.3rem 0.5rem; border-radius: 6px; display: inline-block; }
.table-wrap { overflow-x: auto; margin-bottom: 1rem; }
table { border-collapse: collapse; width: 100%; min-width: 30rem; }
th, td { text-align: left; vertical-align: top; padding: 0.6rem 0.75rem; border-bottom: 1px solid var(--border); }
th { background: var(--bg-alt); }
.faq details { background: var(--surface); border: 1px solid var(--border); border-radius: 10px; padding: 0.1rem 1rem; margin-bottom: 0.6rem; }
.faq summary { cursor: pointer; font-weight: 600; padding: 0.7rem 0; }
.faq details[open] summary { border-bottom: 1px solid var(--border); margin-bottom: 0.7rem; }
.toc { background: var(--bg-alt); border-radius: 12px; padding: 0.9rem 1.2rem; }
.toc p { margin-bottom: 0.4rem; font-weight: 600; }
.toc ul { margin: 0; columns: 14rem; }
.guide-list { display: grid; gap: 1rem; margin-top: 1rem; }
.guide-list h3 { margin: 0 0 0.4rem; }
.guide-list p:last-child { margin-bottom: 0; }

/* footer */
.site-footer { border-top: 1px solid var(--border); background: var(--bg-alt); padding-block: 2rem 1.5rem; margin-top: 1rem; color: var(--muted); font-size: 0.95rem; }
.foot-grid { display: grid; gap: 1.5rem; }
.foot-brand { color: var(--text); font-weight: 700; font-size: 1.05rem; margin-bottom: 0.3rem; }
.foot-title { color: var(--text); font-weight: 650; margin-bottom: 0.4rem; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.foot-legal { margin-top: 1.5rem; padding-top: 1rem; border-top: 1px solid var(--border); }
.foot-legal p { margin-bottom: 0.4rem; }

/* illustration (inline SVG) */
.il-frame { fill: var(--surface); stroke: var(--border); stroke-width: 2; }
.il-bar-top { fill: var(--bg-alt); }
.il-row { fill: var(--bg-alt); }
.il-row-sel { fill: var(--callout-bg); stroke: var(--callout-border); stroke-width: 1.5; }
.il-line { fill: var(--border); }
.il-card { fill: var(--surface); stroke: var(--border); stroke-width: 1.5; }
.il-text { fill: var(--text); font: 600 13px var(--font); }
.il-small { fill: var(--muted); font: 11.5px var(--font); }
.il-chip { fill: #ffffff; font: 700 11px var(--font); }
.il-btn { fill: var(--btn-bg); }
.il-btn-text { fill: var(--btn-text); font: 700 13px var(--font); }
.chip-red { fill: var(--chip-red); }
.chip-blue { fill: var(--chip-blue); }
.chip-green { fill: var(--chip-green); }
.chip-purple { fill: var(--chip-purple); }
.il-dot { fill: var(--border); }

@media (min-width: 40em) {
  .wrap { padding-inline: 1.5rem; }
  .spec { grid-template-columns: max-content 1fr; }
  .spec dt { margin-top: 0; }
  .foot-grid { grid-template-columns: 2fr 1fr 1fr; }
  .guide-list { grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr)); }
}
@media (min-width: 56em) {
  .hero { padding-block: 3.5rem 4rem; }
  .hero-grid { grid-template-columns: 1.05fr 0.95fr; gap: 3rem; }
  .hero-art { align-self: start; margin-top: 2.5rem; }
  .two-col { grid-template-columns: 1fr 1fr; gap: 2.5rem; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}
@media print {
  .site-header, .site-footer, .skip-link, .cta-row { display: none; }
  body { background: #fff; color: #000; }
}