:root {
  --bg: #f7f9fc;
  --paper: #ffffff;
  --ink: #142033;
  --muted: #5d6a7c;
  --line: #dfe6ef;
  --navy: #10182a;
  --blue: #2563eb;
  --cyan: #10b9c5;
  --green: #18a36d;
  --iobit: #2a7ef0;
  --revo: #f0a128;
  --soft: #f0f5fa;
  --radius: 22px;
  --shadow: 0 18px 50px rgba(22, 37, 63, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; }
img, svg { max-width: 100%; }
button, a { -webkit-tap-highlight-color: transparent; }

.skip-link {
  position: fixed;
  left: 1rem;
  top: 1rem;
  z-index: 999;
  background: #fff;
  padding: .75rem 1rem;
  border-radius: 10px;
  transform: translateY(-180%);
  box-shadow: var(--shadow);
}
.skip-link:focus { transform: translateY(0); }

.shell { width: min(1160px, calc(100% - 40px)); margin: 0 auto; }
.reading-width { width: min(820px, calc(100% - 40px)); }
.narrow { max-width: 760px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(247,249,252,.92);
  border-bottom: 1px solid rgba(223,230,239,.85);
  backdrop-filter: blur(16px);
}
.nav-shell { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; text-decoration: none; letter-spacing: -.02em; white-space: nowrap; }
.brand-mark { width: 35px; height: 35px; border-radius: 11px; display: grid; place-items: center; background: var(--navy); color: white; }
.brand-mark svg { width: 21px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.top-nav { display: flex; align-items: center; gap: 4px; }
.top-nav a { padding: 9px 11px; color: #526176; font-size: .91rem; font-weight: 650; text-decoration: none; border-radius: 10px; }
.top-nav a:hover, .top-nav a:focus-visible { background: #e9eff7; color: var(--ink); outline: none; }

.hero { position: relative; overflow: hidden; padding: 76px 0 64px; background: linear-gradient(135deg,#f8fbff 0%,#eef5fb 62%,#e9f8f7 100%); border-bottom: 1px solid var(--line); }
.hero::before { content: ""; position: absolute; width: 480px; height: 480px; border-radius: 50%; right: -180px; top: -220px; background: rgba(16,185,197,.1); filter: blur(4px); }
.hero-grid { position: relative; display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(310px, .7fr); align-items: center; gap: 60px; }
.eyebrow, .kicker, .mini-label { text-transform: uppercase; letter-spacing: .1em; font-size: .76rem; font-weight: 850; color: #37737b; }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; margin-bottom: 16px; padding: 7px 10px; border: 1px solid #cce8e8; background: #f2ffff; border-radius: 999px; }
.pulse { width: 7px; height: 7px; border-radius: 50%; background: #16a773; box-shadow: 0 0 0 5px rgba(22,167,115,.12); }
h1, h2, h3 { line-height: 1.13; letter-spacing: -.035em; margin-top: 0; }
h1 { font-size: clamp(2.65rem, 6vw, 4.75rem); max-width: 900px; margin-bottom: 22px; }
h2 { font-size: clamp(1.8rem, 3.3vw, 2.7rem); margin-bottom: 16px; }
h3 { font-size: 1.2rem; }
p { margin: 0 0 1rem; }
.hero-lead { font-size: clamp(1.08rem, 2vw, 1.25rem); color: #34465f; max-width: 820px; }
.hero-copy > p:not(.hero-lead) { color: var(--muted); max-width: 790px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 28px 0 24px; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 12px 18px; border-radius: 12px; font-weight: 800; text-decoration: none; transition: transform .18s ease, box-shadow .18s ease, background .18s ease; }
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--navy); color: #fff; box-shadow: 0 10px 24px rgba(16,24,42,.16); }
.btn-primary:hover { box-shadow: 0 14px 30px rgba(16,24,42,.23); }
.btn-ghost { border: 1px solid #bdc8d8; background: rgba(255,255,255,.62); }
.btn-dark { background: #fff; color: var(--navy); }
.full { width: 100%; }
.signal-row { display: flex; flex-wrap: wrap; gap: 8px; padding: 0; margin: 0; list-style: none; }
.signal-row li { padding: 6px 10px; border: 1px solid #d4dee9; border-radius: 999px; background: rgba(255,255,255,.75); color: #516278; font-size: .84rem; font-weight: 700; }
.hero-panel { background: rgba(255,255,255,.78); border: 1px solid rgba(204,216,230,.9); border-radius: 26px; padding: 26px; box-shadow: var(--shadow); backdrop-filter: blur(8px); }
.mini-label { color: #6d7a8a; margin-bottom: 16px; }
.mini-choice { display: flex; gap: 12px; align-items: flex-start; padding: 16px 0; border-bottom: 1px solid #e2e8f0; }
.mini-choice strong { display: block; margin-bottom: 3px; font-size: 1.08rem; }
.mini-choice small { display: block; color: #68778b; line-height: 1.45; }
.choice-dot { width: 11px; height: 11px; border-radius: 50%; margin-top: 7px; flex: 0 0 auto; }
.iobit-dot { background: var(--iobit); }
.revo-dot { background: var(--revo); }
.mini-note { margin-top: 18px; padding: 14px 15px; border-radius: 14px; background: #edf4f7; color: #516174; font-size: .9rem; }

.section { padding: 78px 0; }
.soft { background: var(--soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { margin-bottom: 30px; }
.section-head p { color: var(--muted); max-width: 780px; }
.kicker { display: block; margin-bottom: 9px; }

.choice-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 22px; }
.choice-card, .offer-card, .problem-card { background: var(--paper); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: 0 10px 28px rgba(18,36,61,.055); }
.choice-card { padding: 28px; border-top-width: 5px; }
.iobit-card { border-top-color: var(--iobit); }
.revo-card { border-top-color: var(--revo); }
.card-topline { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 18px; color: #41516a; font-weight: 850; }
.tag { font-size: .74rem; padding: 5px 8px; border-radius: 999px; background: #eef3f8; color: #66758a; white-space: nowrap; }
.check-list { padding-left: 0; list-style: none; margin: 18px 0; }
.check-list li { position: relative; padding: 7px 0 7px 29px; border-bottom: 1px dashed #e2e8f0; }
.check-list li::before { content: "✓"; position: absolute; left: 0; top: 7px; width: 20px; height: 20px; display: grid; place-items: center; border-radius: 50%; background: #eaf8f1; color: #16865d; font-weight: 900; font-size: .76rem; }
.card-note { margin: 18px 0 0; padding-top: 16px; border-top: 1px solid #e6ebf2; color: var(--muted); font-size: .91rem; }

.problem-grid { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 18px; }
.problem-card { padding: 24px; position: relative; overflow: hidden; }
.problem-num { display: inline-block; margin-bottom: 13px; color: #8795a8; font-weight: 900; font-size: .78rem; letter-spacing: .12em; }
.problem-card p { color: var(--muted); font-size: .95rem; }
.lean { display: block; margin-top: 16px; color: #34475e; font-size: .9rem; }

.fact-box { margin-top: 24px; padding: 18px 20px; background: #eef7f6; border: 1px solid #cfe8e5; border-left: 4px solid var(--cyan); border-radius: 15px; color: #38535b; }

.table-wrap { overflow-x: auto; border-radius: 18px; border: 1px solid var(--line); box-shadow: 0 10px 30px rgba(16,24,42,.06); background: white; }
table { width: 100%; border-collapse: collapse; min-width: 760px; }
th, td { text-align: left; padding: 17px 18px; vertical-align: top; border-bottom: 1px solid #e4eaf1; }
thead th { background: #152238; color: white; font-size: .88rem; letter-spacing: .01em; }
tbody th { width: 23%; color: #26364d; background: #fafbfd; }
tbody td { width: 38.5%; color: #536174; }
tbody tr:last-child th, tbody tr:last-child td { border-bottom: 0; }

.need-grid { display: grid; border: 1px solid var(--line); border-radius: 18px; overflow: hidden; background: #fff; }
.need-row { display: grid; grid-template-columns: 1.2fr .8fr; gap: 20px; padding: 17px 20px; border-bottom: 1px solid var(--line); align-items: center; }
.need-row:last-child { border-bottom: 0; }
.need-row span { color: #5c6a7e; }
.need-row strong { text-align: right; color: #263952; }

.dark-section { background: #10182a; color: #f6f9ff; }
.dark-section p { color: #c4cedc; }
.light-kicker { color: #76d9dc; }
.safety-grid { display: grid; grid-template-columns: 1.2fr .8fr; gap: 48px; align-items: center; }
.safety-panel { padding: 26px; border-radius: 20px; background: #18243a; border: 1px solid #283953; }
.safety-panel h3 { margin-bottom: 13px; }
.safety-panel ul { margin: 0; padding-left: 19px; color: #d1d9e6; }
.safety-panel li + li { margin-top: 8px; }

.offer-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 20px; }
.offer-card { padding: 26px; }
.offer-badge { display: inline-block; margin-bottom: 16px; padding: 6px 9px; border-radius: 999px; background: #e9f8f1; color: #13724f; font-size: .78rem; font-weight: 850; }
.offer-card p { color: var(--muted); }
.deep-dive { margin-top: 22px; padding: 26px; border-radius: 20px; background: #17243a; color: white; display: flex; justify-content: space-between; align-items: center; gap: 30px; }
.deep-dive p { max-width: 710px; margin: 0; color: #cdd6e3; }
.deep-dive h3 { margin-bottom: 8px; font-size: 1.45rem; }
.deep-dive .mini-label { color: #8bd8dd; }

.related-card { display: grid; grid-template-columns: auto 1fr auto; gap: 22px; align-items: center; padding: 28px; border: 1px solid #ccd7e5; border-radius: 22px; background: linear-gradient(135deg,#fff,#eef6fb); }
.related-card h2 { font-size: clamp(1.55rem,2.5vw,2.1rem); margin-bottom: 8px; }
.related-card p { margin: 0; color: var(--muted); }
.related-icon { width: 50px; height: 50px; display: grid; place-items: center; border-radius: 15px; background: var(--navy); color: white; font-size: 1.4rem; }
.dark-ghost { background: #fff; }

.faq-wrap details { background: #fff; border: 1px solid var(--line); border-radius: 15px; padding: 0 18px; margin-bottom: 10px; }
.faq-wrap summary { cursor: pointer; padding: 17px 30px 17px 0; font-weight: 800; position: relative; }
.faq-wrap summary::after { content: "+"; position: absolute; right: 2px; top: 13px; font-size: 1.5rem; color: #7b899b; }
.faq-wrap details[open] summary::after { content: "–"; }
.faq-wrap details p { color: var(--muted); padding: 0 0 17px; margin: 0; }

.source-section { background: #fff; }
.source-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 48px; align-items: start; }
.source-grid p { color: var(--muted); }
.source-links { display: grid; gap: 9px; }
.source-links a { display: flex; justify-content: space-between; gap: 12px; padding: 13px 15px; border: 1px solid var(--line); border-radius: 12px; color: #3a4c64; text-decoration: none; font-size: .92rem; background: #fbfcfe; }
.source-links a:hover { border-color: #b5c4d7; background: #f5f8fb; }
.disclosure { margin: 28px 0 0; padding: 16px 18px; border-radius: 14px; background: #f6f8fb; border: 1px solid #e2e8f0; color: #59697b; font-size: .88rem; }
.disclosure code { background: #e9eef5; padding: 2px 5px; border-radius: 5px; }

.site-footer { padding: 34px 0; background: #0d1524; color: #eff4fb; }
.footer-grid { display: grid; grid-template-columns: 1fr auto; gap: 30px; align-items: end; }
.site-footer strong { font-size: 1.08rem; }
.site-footer p { margin: 6px 0 0; color: #9fafc2; font-size: .9rem; }
.footer-meta { display: flex; flex-direction: column; text-align: right; color: #9fafc2; font-size: .82rem; }

:focus-visible { outline: 3px solid rgba(37,99,235,.42); outline-offset: 3px; }

@media (max-width: 980px) {
  .hero-grid, .safety-grid, .source-grid { grid-template-columns: 1fr; gap: 34px; }
  .hero-panel { max-width: 720px; }
  .problem-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .related-card { grid-template-columns: auto 1fr; }
  .related-card .btn { grid-column: 2; justify-self: start; }
}

@media (max-width: 760px) {
  .shell { width: min(100% - 28px, 1160px); }
  .reading-width { width: min(100% - 28px, 820px); }
  .nav-shell { min-height: 66px; overflow: hidden; }
  .brand span:last-child { display: none; }
  .top-nav { overflow-x: auto; overscroll-behavior-inline: contain; scrollbar-width: none; }
  .top-nav::-webkit-scrollbar { display: none; }
  .top-nav a { white-space: nowrap; font-size: .84rem; padding-inline: 9px; }
  .hero { padding: 52px 0 48px; }
  h1 { font-size: clamp(2.25rem, 11vw, 3.25rem); }
  .section { padding: 60px 0; }
  .choice-grid, .offer-grid, .problem-grid { grid-template-columns: 1fr; }
  .deep-dive { align-items: stretch; flex-direction: column; }
  .deep-dive .btn { align-self: flex-start; }
  .need-row { grid-template-columns: 1fr; gap: 3px; }
  .need-row strong { text-align: left; }
  .related-card { grid-template-columns: 1fr; }
  .related-card .btn { grid-column: auto; justify-self: stretch; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-meta { text-align: left; }
}

@media (max-width: 430px) {
  .hero-actions .btn { width: 100%; }
  .choice-card, .problem-card, .offer-card { padding: 21px; }
  .card-topline { align-items: flex-start; flex-direction: column; }
  .hero-panel { padding: 21px; }
  .signal-row li { font-size: .78rem; }
  .deep-dive, .related-card { padding: 21px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}