:root {
  color-scheme: dark;
  --wa: #25d366;
  --wa-dark: #1da851;
  --bg: #0a0a0a;
  --panel: #111111;
  --line: #252525;
  --text: #e5e7eb;
  --muted: #9ca3af;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  line-height: 1.65;
}
a { color: inherit; }
a:focus-visible { outline: 2px solid var(--wa); outline-offset: 4px; }
.skip-link { position: absolute; left: -9999px; top: 1rem; z-index: 10; padding: .75rem 1rem; background: var(--wa); color: #07130b; }
.skip-link:focus { left: 1rem; }
.site-header { position: sticky; top: 0; z-index: 5; border-bottom: 1px solid rgba(255,255,255,.07); background: rgba(10,10,10,.94); backdrop-filter: blur(14px); }
.header-inner, .container { width: min(100% - 2rem, 1120px); margin-inline: auto; }
.header-inner { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; }
.brand { text-decoration: none; font-size: 1.15rem; font-weight: 750; letter-spacing: -.04em; white-space: nowrap; }
.brand span { color: var(--wa); }
.nav-links { display: flex; align-items: center; gap: 1.5rem; color: var(--muted); font-size: .9rem; }
.nav-links a { text-decoration: none; transition: color .2s; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--wa); }
.demo-link { padding: .65rem .95rem; border-radius: .6rem; background: var(--wa); color: #06110a; font-weight: 700; font-size: .88rem; text-decoration: none; white-space: nowrap; }
.demo-link:hover { background: var(--wa-dark); }
.hero { padding: clamp(4rem, 9vw, 7.5rem) 0 3rem; background: radial-gradient(ellipse at top, rgba(37,211,102,.1), transparent 62%); }
.eyebrow { margin: 0 0 .9rem; color: var(--wa); font-size: .76rem; font-weight: 750; letter-spacing: .17em; text-transform: uppercase; }
h1, h2, h3 { color: #fff; line-height: 1.18; letter-spacing: -.035em; }
h1 { max-width: 850px; margin: 0; font-size: clamp(2.4rem, 6vw, 4.5rem); }
.hero-copy { max-width: 720px; margin: 1.4rem 0 0; color: var(--muted); font-size: clamp(1.05rem, 2vw, 1.22rem); }
.breadcrumbs { margin: 0 0 1.6rem; color: #777; font-size: .85rem; }
.breadcrumbs a { text-decoration: none; }
.breadcrumbs a:hover { color: var(--wa); }
.content-grid { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: clamp(2rem, 6vw, 5rem); align-items: start; padding-bottom: 5rem; }
.article-list { display: grid; gap: 1rem; }
.article-card { display: block; padding: 1.5rem; border: 1px solid var(--line); border-radius: 1rem; background: linear-gradient(140deg, rgba(255,255,255,.025), transparent 65%); text-decoration: none; transition: border-color .2s, transform .2s; }
.article-card:hover { border-color: rgba(37,211,102,.55); transform: translateY(-2px); }
.article-card h2 { margin: .4rem 0 .65rem; font-size: clamp(1.3rem, 3vw, 1.75rem); }
.article-card p { margin: 0; color: var(--muted); }
.card-meta, .article-meta { color: #858585; font-size: .82rem; }
.topic-tag { display: inline-block; padding: .25rem .6rem; border: 1px solid rgba(37,211,102,.25); border-radius: 999px; color: var(--wa); font-size: .72rem; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; }
.side-card { position: sticky; top: 100px; padding: 1.4rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--panel); }
.side-card h2 { margin: 0 0 .75rem; font-size: 1.1rem; }
.side-card p { margin: 0 0 1rem; color: var(--muted); font-size: .92rem; }
.text-link { color: var(--wa); font-weight: 650; text-decoration: none; }
.text-link:hover { color: #fff; }
.article { max-width: 760px; padding-bottom: 5rem; }
.article h1 { font-size: clamp(2.1rem, 5vw, 3.5rem); }
.article .article-meta { margin: 1rem 0 2rem; }
.article .lead { color: #c3c8c5; font-size: 1.18rem; }
.article h2 { margin: 2.6rem 0 .85rem; font-size: clamp(1.45rem, 3vw, 2rem); }
.article h3 { margin: 1.6rem 0 .6rem; font-size: 1.2rem; }
.article p, .article li { color: #b9bdbb; }
.article ul, .article ol { padding-left: 1.35rem; }
.article li { margin: .45rem 0; }
.article strong { color: #f2f4f2; }
.note { margin: 1.5rem 0; padding: 1rem 1.2rem; border-left: 3px solid var(--wa); border-radius: 0 .7rem .7rem 0; background: rgba(37,211,102,.06); color: #c3c8c5; }
.article-cta { margin-top: 2.5rem; padding: 1.5rem; border: 1px solid rgba(37,211,102,.25); border-radius: 1rem; background: linear-gradient(140deg, rgba(37,211,102,.1), rgba(255,255,255,.015)); }
.article-cta h2 { margin-top: 0; }
.related { margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--line); }
.related ul { list-style: none; padding: 0; }
.related li { margin: .7rem 0; }
.site-footer { padding: 2rem 0; border-top: 1px solid var(--line); color: #777; font-size: .84rem; }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 1rem; }
.footer-inner a { color: #aaa; text-decoration: none; }
.footer-inner a:hover { color: var(--wa); }
@media (max-width: 760px) {
  .header-inner { min-height: 64px; gap: .75rem; }
  .nav-links { gap: .8rem; font-size: .82rem; }
  .nav-links a:not([aria-current="page"]) { display: none; }
  .demo-link { padding: .55rem .7rem; font-size: .8rem; }
  .content-grid { grid-template-columns: 1fr; }
  .side-card { position: static; }
}
@media (max-width: 390px) {
  .brand { font-size: 1rem; }
  .header-inner, .container { width: min(100% - 1.25rem, 1120px); }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; }
}