:root {
  --primary: #009393;
  --primary-hover: #008c8c;
  --primary-light: #7cb0b0;
  --primary-bg: #f6f9f9;
  --header-bg: #001d1d;
  --text: #1f2937;
  --muted: #6b7280;
  --line: #e5e7eb;
  --shadow-cta: 0 20px 45px -15px rgba(0, 111, 111, 0.55);
  --shadow-cta-hover: 0 24px 55px -18px rgba(0, 121, 121, 0.65);
  --shadow-card: 0 4px 20px -8px rgba(0, 42, 42, 0.08), 0 1px 3px rgba(0, 0, 0, 0.03);
}
* { box-sizing: border-box; }
body.scroll-locked { overflow: hidden; }
body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  margin: 0; background: #fff; color: var(--text); line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Preloader ---------- */
#pagePreloader {
  position: fixed; inset: 0; z-index: 9999; display: flex; flex-direction: column;
  background: linear-gradient(to bottom right, #fff, #f9fafb, var(--primary-bg));
  transition: opacity .5s ease;
}
#pagePreloader.hide { opacity: 0; pointer-events: none; }
.pl-bar { height: 6px; width: 100%; overflow: hidden; background: #eef2f2; }
.pl-bar i { display: block; height: 100%; width: 200%;
  background: linear-gradient(90deg, var(--primary), var(--primary-light), var(--primary));
  animation: pl-shimmer 1.5s ease-in-out infinite; }
@keyframes pl-shimmer { 0%{transform:translateX(-50%)} 100%{transform:translateX(0)} }
.pl-mid { flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 28px; padding: 24px; text-align: center; }
.pl-spinner { position: relative; width: 96px; height: 96px; }
.pl-spinner .ring { position: absolute; inset: 0; border-radius: 50%; border: 4px solid rgba(0,147,147,.15); }
.pl-spinner .ring.spin { border-top-color: var(--primary); animation: pl-spin 1s linear infinite; }
@keyframes pl-spin { to { transform: rotate(360deg); } }
.pl-title { font-size: 1.15rem; font-weight: 700; color: #374151; }
.pl-dots { display: flex; gap: 6px; justify-content: center; margin-top: 8px; }
.pl-dots span { width: 8px; height: 8px; border-radius: 50%; background: var(--primary); animation: pl-dot 1.4s ease-in-out infinite; }
.pl-dots span:nth-child(2){ animation-delay:.2s } .pl-dots span:nth-child(3){ animation-delay:.4s }
@keyframes pl-dot { 0%,100%{opacity:.3;transform:scale(.8)} 50%{opacity:1;transform:scale(1)} }
.pl-safe { margin: 0 auto 36px; display: flex; align-items: center; gap: 14px; max-width: 340px;
  background: rgba(255,255,255,.92); border: 1px solid var(--line); border-radius: 16px; padding: 14px 22px; box-shadow: var(--shadow-card); }
.pl-safe .ico { width: 46px; height: 46px; border-radius: 50%; background: var(--primary-bg); display: grid; place-items: center; font-size: 1.3rem; }
.pl-safe b { display: block; font-size: 1rem; } .pl-safe small { color: var(--muted); }

/* ---------- Header ---------- */
.site-header { border-bottom: 1px solid var(--line); background: #fff; position: sticky; top: 0; z-index: 100; }
.site-header .wrap { max-width: 1100px; margin: 0 auto; padding: 12px 18px; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.brand { font-weight: 800; font-size: 1.15rem; color: var(--header-bg); text-decoration: none; display: flex; align-items: center; gap: 8px; }
.brand .dot { width: 26px; height: 26px; border-radius: 8px; background: var(--primary); display: inline-block; }
.nav { display: flex; gap: 22px; }
.nav a { color: #374151; text-decoration: none; font-weight: 500; font-size: .95rem; }
.nav a:hover { color: var(--primary); }
@media (max-width: 860px) { .nav { display: none; } }

/* ---------- Article ---------- */
main.article { max-width: 760px; margin: 0 auto; padding: 22px 16px 90px; }
h1 { font-size: clamp(1.5rem, 4vw, 2rem); line-height: 1.25; margin: 6px 0 10px; text-align: center; font-weight: 800; }
.meta { color: var(--muted); font-size: .9rem; text-align: center; margin-bottom: 20px; }
.prose p { margin: 0 0 1.05rem; font-size: 1.02rem; color: #374151; }
.prose strong { color: #111827; }
.hero-img { width: 100%; border-radius: 16px; aspect-ratio: 16/9; object-fit: cover; background: var(--primary-bg); margin: 8px 0 18px; }

/* ---------- Ad slot ---------- */
.ad-slot { margin: 26px 0; }
.ad-slot .label { display: block; text-align: center; font-size: .68rem; letter-spacing: .08em; text-transform: uppercase; color: #9ca3af; font-weight: 600; margin-bottom: 4px; }
.ad-slot .frame { min-height: 120px; display: flex; align-items: center; justify-content: center; border-radius: 14px; background: var(--primary-bg); }
.hs-ad { min-height: 120px; width: 100%; display: flex; align-items: center; justify-content: center; }
#hs-desktop-top { min-height: 90px; }

/* ---------- Benefit cards ---------- */
.benefits { display: flex; flex-direction: column; gap: 22px; margin: 22px 0; }
.benefit { display: flex; gap: 18px; align-items: flex-start; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.benefit:last-child { border-bottom: 0; }
.benefit .ic { flex: none; width: 52px; height: 52px; border-radius: 50%; background: var(--primary); color: #fff; display: grid; place-items: center; font-size: 1.35rem; box-shadow: var(--shadow-card); }
.benefit h3 { margin: 2px 0 4px; font-size: 1.05rem; }
.benefit p { margin: 0; color: #4b5563; font-size: .96rem; }

/* ---------- Pros ---------- */
.pros h2 { display: flex; align-items: center; gap: 10px; font-size: 1.25rem; margin: 26px 0 12px; }
.pros ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 6px; }
.pros li { display: grid; grid-template-columns: auto 1fr; gap: 12px; align-items: start; padding: 12px 0; border-bottom: 1px solid var(--line); }
.pros li:last-child { border-bottom: 0; }
.pros .chk { width: 34px; height: 34px; border-radius: 50%; background: var(--primary-bg); color: var(--primary); display: grid; place-items: center; font-weight: 800; }
.pros h4 { margin: 2px 0 2px; font-size: 1rem; } .pros li p { margin: 0; color: #4b5563; font-size: .95rem; }

/* ---------- CTA ---------- */
.cta {
  display: flex; align-items: center; justify-content: center; gap: 14px; margin: 26px 0;
  padding: 26px 20px; border-radius: 18px; text-decoration: none; color: #fff; font-weight: 800;
  font-size: clamp(1.1rem, 3vw, 1.5rem); text-transform: uppercase; letter-spacing: .02em;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  box-shadow: var(--shadow-cta); transition: transform .35s ease, box-shadow .35s ease; position: relative; overflow: hidden;
}
.cta:hover { transform: translateY(-3px); box-shadow: var(--shadow-cta-hover); }
.cta .shine { position: absolute; inset: 0; width: 200%; transform: skewX(-12deg);
  background: linear-gradient(90deg, transparent, rgba(255,255,255,.18), transparent); animation: shine 3s ease-in-out infinite; }
@keyframes shine { 0%{transform:translateX(-120%) skewX(-12deg)} 60%,100%{transform:translateX(120%) skewX(-12deg)} }
.hstk-locked { filter: grayscale(.3); }
.hstk-locked .shine { display: none; }

/* ---------- Author + Footer ---------- */
.author { margin: 40px 0 10px; padding: 26px; border-radius: 18px; background: var(--primary-bg); text-align: center; }
.author .ava { width: 96px; height: 96px; border-radius: 50%; background: var(--header-bg); color: #fff; display: grid; place-items: center; font-size: 2rem; margin: 0 auto 12px; }
.author h3 { margin: 0 0 6px; } .author p { color: #4b5563; margin: 0 auto 10px; max-width: 520px; font-size: .95rem; }
.author a { color: var(--primary); font-weight: 600; text-decoration: none; }
.site-footer { border-top: 1px solid var(--line); background: #fafafa; margin-top: 40px; padding: 30px 18px; color: var(--muted); }
.site-footer .cols { max-width: 1000px; margin: 0 auto; display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 28px; }
.site-footer h4 { color: #374151; margin: 0 0 10px; font-size: .95rem; }
.site-footer ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 7px; }
.site-footer a { color: #6b7280; text-decoration: none; font-size: .9rem; } .site-footer a:hover { color: var(--primary); }
.site-footer .copy { text-align: center; margin-top: 22px; font-size: .82rem; }
@media (max-width: 700px) { .site-footer .cols { grid-template-columns: 1fr; } }

/* ---------- Read progress ---------- */
.read-progress { position: fixed; top: 0; left: 0; height: 3px; width: 0%; background: var(--primary); z-index: 200; transition: width .1s; }

/* ---------- Homepage ---------- */
.home-hero { background: linear-gradient(160deg, #001d1d, #013535 60%, #001d1d); color: #fff; text-align: center; padding: 46px 18px 54px; }
.home-hero .logo { font-weight: 800; font-size: 1.4rem; display: inline-flex; align-items: center; gap: 8px; }
.home-hero .logo .dot { width: 24px; height: 24px; border-radius: 7px; background: var(--primary); }
.home-hero h1 { color: #fff; font-size: clamp(1.7rem, 5vw, 2.6rem); margin: 16px 0 8px; }
.home-hero p { color: #a7c6c6; max-width: 620px; margin: 0 auto; font-size: 1rem; }
.home-wrap { max-width: 1100px; margin: 0 auto; padding: 30px 16px 60px; }
.feat-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 24px; }
.feat-main .card-img { width: 100%; aspect-ratio: 16/9; border-radius: 14px; object-fit: cover; background: var(--primary-bg); }
.feat-main h2 { font-size: 1.5rem; margin: 12px 0 6px; }
.side-list { display: flex; flex-direction: column; gap: 14px; background: var(--primary-bg); border-radius: 14px; padding: 16px; }
.side-item { display: grid; grid-template-columns: 64px 1fr; gap: 12px; align-items: center; }
.side-item img { width: 64px; height: 48px; border-radius: 8px; object-fit: cover; background: #dbe7e7; }
.side-item .tag { font-size: .68rem; color: var(--muted); text-transform: uppercase; }
.side-item a { color: #111827; text-decoration: none; font-weight: 600; font-size: .9rem; }
.side-item a:hover { color: var(--primary); }
.sec-title { display: flex; align-items: center; gap: 10px; font-size: 1.35rem; margin: 40px 0 16px; }
.sec-title::before { content: ""; width: 8px; height: 22px; border-radius: 4px; background: var(--primary); display: inline-block; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card { text-decoration: none; color: inherit; display: flex; flex-direction: column; gap: 8px; }
.card img { width: 100%; aspect-ratio: 16/10; border-radius: 12px; object-fit: cover; background: var(--primary-bg); }
.card .tag { font-size: .68rem; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.card h3 { margin: 0; font-size: 1rem; line-height: 1.35; }
.card:hover h3 { color: var(--primary); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 6px 0 18px; }
.chip { padding: 8px 16px; border-radius: 999px; background: var(--primary-bg); color: #374151; font-weight: 600; font-size: .85rem; border: 1px solid var(--line); }
.chip.active { background: var(--primary); color: #fff; border-color: var(--primary); }
@media (max-width: 860px) { .feat-grid { grid-template-columns: 1fr; } .cards { grid-template-columns: 1fr 1fr; } }
@media (max-width: 560px) { .cards { grid-template-columns: 1fr; } }

/* ---------- Article table of contents ---------- */
.toc { background: var(--primary-bg); border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; margin: 18px 0; }
.toc h4 { margin: 0 0 10px; font-size: 1rem; }
.toc ol { margin: 0; padding-left: 20px; color: #4b5563; }
.toc a { color: #374151; text-decoration: none; font-size: .93rem; }
.toc a:hover { color: var(--primary); }
.faq { margin: 24px 0; }
.faq details { border-bottom: 1px solid var(--line); padding: 12px 0; }
.faq summary { font-weight: 700; cursor: pointer; }
.faq p { margin: 8px 0 0; color: #4b5563; }
.related { margin: 30px 0; }
.related .cards { grid-template-columns: repeat(2, 1fr); }
h2.section { font-size: 1.3rem; margin: 28px 0 10px; }