/* os.24hgaming.com, the Atrium site. One stylesheet, no scripts needed.
   The file name carries a date on purpose: stylesheets and pictures are cached for a week as "immutable"
   (nginx.conf), so a changed file needs a new name or returning visitors keep the old one. */
:root {
    --bg: #070b12;
    --bg-soft: #0b111b;
    --card: #0e1522;
    --line: #1b2638;
    --line-bright: #25344d;
    --text: #b9c2d0;
    --text-dim: #7f8ba0;
    --bright: #f2f5f9;
    --accent: #00e5ff;
    --accent-ink: #04202a;
    --ok: #4fd08a;
    --radius: 14px;
    --wrap: 1120px;
    --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, system-ui, sans-serif;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font); font-size: 17px; line-height: 1.6; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, .btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }
h1, h2, h3 { color: var(--bright); line-height: 1.15; margin: 0; letter-spacing: -0.01em; }
p { margin: 0; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.skip { position: absolute; left: -9999px; top: 0; background: var(--accent); color: var(--accent-ink); padding: 10px 16px; z-index: 100; font-weight: 600; }
.skip:focus { left: 12px; top: 12px; }

/* header */
.top { position: sticky; top: 0; z-index: 20; background: rgba(7, 11, 18, 0.86); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); border-bottom: 1px solid var(--line); }
.top .wrap { display: flex; align-items: center; gap: 20px; min-height: 64px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--bright); font-weight: 700; font-size: 18px; }
.brand:hover { text-decoration: none; }
.brand img { height: 30px; width: auto; }
.brand span { padding-left: 12px; border-left: 1px solid var(--line-bright); }
.nav { display: flex; align-items: center; gap: 6px 22px; margin-left: auto; flex-wrap: wrap; font-size: 15px; }
.nav a { color: var(--text); }
.nav a:hover, .nav a[aria-current="page"] { color: var(--bright); text-decoration: none; }
.nav a.btn { color: var(--accent-ink); }

/* buttons */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 12px 20px; border-radius: 10px; font-weight: 650; font-size: 16px; border: 1px solid transparent; line-height: 1.2; }
.btn:hover { text-decoration: none; }
.btn-main { background: var(--accent); color: var(--accent-ink); }
.btn-main:hover { background: #5ff0ff; }
.btn-line { border-color: var(--line-bright); color: var(--bright); background: transparent; }
.btn-line:hover { border-color: var(--accent); color: var(--accent); }
.btn-small { padding: 8px 14px; font-size: 14px; }

/* hero */
.hero { padding: 72px 0 56px; background: radial-gradient(1100px 520px at 78% -10%, rgba(0, 229, 255, 0.10), transparent 62%); }
.hero .wrap { display: grid; grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr); gap: 48px; align-items: center; }
.pill { display: inline-flex; align-items: center; gap: 10px; padding: 7px 14px; border: 1px solid var(--line-bright); border-radius: 999px; font-size: 14px; color: var(--bright); background: var(--bg-soft); margin-bottom: 22px; }
.pill i { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 0 rgba(0, 229, 255, 0.6); animation: pulse 2.4s infinite; }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 rgba(0, 229, 255, 0.55); } 70% { box-shadow: 0 0 0 9px rgba(0, 229, 255, 0); } 100% { box-shadow: 0 0 0 0 rgba(0, 229, 255, 0); } }
.hero h1 { font-size: clamp(36px, 5vw, 58px); font-weight: 800; }
.hero h1 em { font-style: normal; color: var(--accent); }
.lead { font-size: 19px; margin-top: 20px; max-width: 34em; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.shot { border: 1px solid var(--line-bright); border-radius: var(--radius); overflow: hidden; background: #05080d; box-shadow: 0 30px 80px rgba(0, 0, 0, 0.55), 0 0 0 1px rgba(0, 229, 255, 0.05); }
.shot img { width: 100%; }

/* sections */
section { padding: 72px 0; }
section.soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.kicker { color: var(--accent); font-size: 13px; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; margin-bottom: 12px; }
.sect-head { max-width: 46em; margin-bottom: 44px; }
.sect-head h2 { font-size: clamp(28px, 3.4vw, 40px); font-weight: 780; }
.sect-head p { margin-top: 14px; font-size: 18px; }

/* what it does: picture and text, side by side, alternating */
.row { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr); gap: 44px; align-items: center; padding: 34px 0; }
.row + .row { border-top: 1px solid var(--line); }
.row.flip { grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr); }
.row.flip .shot { order: 2; }
.first { margin-bottom: 10px; max-width: 46em; }
.first h3 { font-size: 22px; }
.row h3 { font-size: 26px; font-weight: 740; }
.row p { margin-top: 14px; }
.note { margin-top: 14px; font-size: 14.5px; color: var(--text-dim); padding-left: 12px; border-left: 2px solid var(--line-bright); }
figure { margin: 0; }
figcaption { font-size: 13.5px; color: var(--text-dim); padding: 9px 14px; border-top: 1px solid var(--line); background: var(--bg-soft); }

/* cards */
.cards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.card h3 { font-size: 19px; font-weight: 700; margin-bottom: 9px; }
.card p { font-size: 16px; }
.card svg { width: 30px; height: 30px; margin-bottom: 16px; stroke: var(--accent); fill: none; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.tag { display: inline-block; font-size: 12px; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-dim); border: 1px solid var(--line-bright); border-radius: 999px; padding: 3px 10px; margin-bottom: 14px; }

/* where it stands */
.two { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.list { list-style: none; margin: 0; padding: 0; }
.list li { position: relative; padding: 9px 0 9px 32px; border-top: 1px solid var(--line); }
.list li:first-child { border-top: 0; }
.list li::before { content: ""; position: absolute; left: 2px; top: 15px; width: 14px; height: 14px; border-radius: 50%; border: 2px solid var(--line-bright); }
.list.done li::before { border-color: var(--ok); background: radial-gradient(circle, var(--ok) 0 4px, transparent 5px); }
.list.now li::before { border-color: var(--accent); }
.plain { margin-top: 26px; font-size: 18px; color: var(--bright); }

/* closing band */
.band { text-align: center; padding: 76px 0; background: radial-gradient(800px 320px at 50% 120%, rgba(0, 229, 255, 0.12), transparent 65%); }
.band h2 { font-size: clamp(28px, 3.4vw, 40px); font-weight: 780; }
.band p { margin: 14px auto 0; max-width: 36em; font-size: 18px; }
.band .actions { justify-content: center; }

/* text pages */
.page { padding: 64px 0 80px; }
.page h1 { font-size: clamp(32px, 4.4vw, 48px); font-weight: 800; }
.page .lead { max-width: 40em; }
.page h2 { font-size: 26px; font-weight: 740; margin: 46px 0 14px; }
.page h3 { font-size: 19px; font-weight: 700; margin: 26px 0 6px; }
.page p + p { margin-top: 12px; }
.narrow { max-width: 780px; }
.qa { border-top: 1px solid var(--line); padding: 20px 0; }
.qa h3 { margin: 0 0 8px; }

/* footer */
footer { border-top: 1px solid var(--line); padding: 44px 0 36px; font-size: 15px; color: var(--text-dim); }
footer .cols { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 28px; }
footer h2 { font-size: 13px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text); margin-bottom: 10px; font-weight: 700; }
footer a { color: var(--text); display: block; padding: 3px 0; }
footer a:hover { color: var(--accent); text-decoration: none; }
footer .fine { margin-top: 30px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 13.5px; }
footer .fine a { display: inline; padding: 0; color: var(--text-dim); text-decoration: underline; }

@media (max-width: 900px) {
    body { font-size: 16px; }
    .hero { padding: 44px 0 36px; }
    .hero .wrap, .row, .row.flip, .two { grid-template-columns: minmax(0, 1fr); gap: 26px; }
    .row.flip .shot { order: 0; }
    .cards { grid-template-columns: minmax(0, 1fr); }
    section { padding: 52px 0; }
    footer .cols { grid-template-columns: minmax(0, 1fr); }
    .nav { margin-left: 0; width: 100%; padding-bottom: 12px; gap: 6px 16px; }
    .top .wrap { gap: 6px 16px; padding-top: 10px; }
}
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .pill i { animation: none; }
}

/* the download page (2026-10-09): the file, the steps, short commands */
strong { color: var(--bright); font-weight: 650; }
code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 0.88em; color: var(--bright); background: var(--bg-soft); border: 1px solid var(--line); border-radius: 6px; padding: 1px 6px; overflow-wrap: anywhere; }
.dl { margin-top: 30px; padding: 26px; background: var(--card); border: 1px solid var(--line-bright); border-radius: var(--radius); }
.dl p { margin-top: 14px; }
.dl .sum { font-size: 14.5px; color: var(--text-dim); }
.steps { margin: 0; padding: 0 0 0 1.5em; }
.steps li { padding: 10px 0 10px 6px; border-top: 1px solid var(--line); }
.steps li:first-child { border-top: 0; }
.steps li::marker { color: var(--accent); font-weight: 700; }
.page .shot { margin-top: 22px; }
.page .note { margin-top: 18px; }

/* 2026-10-10: the two installers side by side on the download page, each with its own button. */
.pick { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-top: 30px; }
.pick .dl { margin-top: 0; display: flex; flex-direction: column; align-items: flex-start; }
.pick .dl h2 { font-size: 22px; font-weight: 740; margin: 0; }
.pick .dl .facts { margin-top: 8px; font-size: 14.5px; color: var(--bright); }
.pick .dl .what { flex: 1 0 auto; }
.pick .dl .what a { color: var(--accent); }
.pick .dl .btn { margin-top: 20px; }
.pick + .sum { margin-top: 16px; }
.hero .sum { margin-top: 18px; max-width: 36em; }
.hero .sum a { color: var(--accent); }
@media (max-width: 900px) {
    .pick { grid-template-columns: minmax(0, 1fr); }
    .pick .dl .btn { align-self: stretch; justify-content: center; text-align: center; }
}