:root {
  --ink: #101114;
  --ink-soft: #3f4249;
  --muted: #747780;
  --red: #e50922;
  --red-dark: #bd061a;
  --paper: #f7f6f2;
  --white: #fff;
  --line: rgba(16, 17, 20, .1);
  --shadow: 0 24px 70px rgba(28, 25, 23, .14);
  --font: "Avenir Next", Avenir, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { overflow-x: hidden; scroll-behavior: smooth; }
body { margin: 0; overflow-x: hidden; color: var(--ink); background: var(--paper); font-family: var(--font); line-height: 1.6; -webkit-font-smoothing: antialiased; }
img { display: block; max-width: 100%; }
.shell { width: min(1220px, 100%); margin: 0 auto; padding-inline: 32px; }
.section { padding-block: 120px; }
.skip-link { position: fixed; z-index: 100; top: 10px; left: 10px; padding: 8px 12px; border-radius: 8px; background: var(--ink); color: #fff; font-size: 12px; text-decoration: none; transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }

.nav-wrap { position: sticky; z-index: 30; top: 0; border-bottom: 1px solid var(--line); background: rgba(247, 246, 242, .88); backdrop-filter: blur(18px); }
.nav { min-height: 72px; display: flex; align-items: center; gap: 10px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); font-size: 18px; font-weight: 850; text-decoration: none; white-space: nowrap; }
.brand-mark { width: 44px; height: 32px; display: grid; place-items: center; padding-left: 2px; border-radius: 9px; background: var(--red); color: #fff; font-size: 11px; }
.nav-links { display: flex; align-items: center; gap: 28px; margin-left: auto; margin-right: 22px; }
.nav-links a, .nav-login { color: var(--ink-soft); font-size: 13px; font-weight: 750; text-decoration: none; }
.nav-links a:hover, .nav-login:hover { color: var(--red); }
.nav-login { padding: 10px 14px; }
.nav-start { min-height: 42px; display: inline-flex; align-items: center; gap: 12px; padding: 0 17px; border-radius: 9px; background: var(--ink); color: #fff; font-size: 13px; font-weight: 800; text-decoration: none; }
.nav-start:hover { background: var(--red); }
.nav-feedback {
  margin-left: auto;
  min-height: 36px;
  padding: 0 14px;
  border: 1px solid rgba(16, 17, 20, .14);
  border-radius: 9px;
  background: #fff;
  color: var(--ink);
  font: inherit;
  font-size: 13px;
  font-weight: 750;
  cursor: pointer;
}
.nav-feedback:hover { border-color: var(--red); color: var(--red); }
.nav-feedback:focus-visible { outline: 2px solid var(--red); outline-offset: 3px; }
body.feedback-open { overflow: hidden; }
.feedback-backdrop {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: none;
  place-items: center;
  padding: 24px;
  background: rgba(16, 17, 20, .46);
}
.feedback-backdrop.is-open { display: grid; }
.feedback-dialog {
  position: relative;
  width: min(360px, 100%);
  padding: 28px 24px 22px;
  border-radius: 16px;
  background: #fff;
  box-shadow: 0 24px 70px rgba(16, 17, 20, .22);
  text-align: center;
}
.feedback-close {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 32px;
  height: 32px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  color: var(--muted);
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
}
.feedback-close:hover { color: var(--ink); background: rgba(16, 17, 20, .06); }
.feedback-dialog h2 { margin: 0; font-size: 18px; font-weight: 850; }
.feedback-dialog p { margin: 8px 0 0; color: var(--muted); font-size: 13px; line-height: 1.6; }
.feedback-dialog img {
  width: min(240px, 100%);
  height: auto;
  max-height: min(58vh, 420px);
  margin: 18px auto 0;
  object-fit: contain;
}
.feedback-hint { margin-top: 12px !important; font-size: 12px !important; }

.hero { min-height: 680px; display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: clamp(44px, 6vw, 72px); padding-top: 88px; padding-bottom: 94px; }
.eyebrow { margin: 0 0 18px; color: var(--red); font-size: 11px; font-weight: 900; letter-spacing: .14em; text-transform: uppercase; }
.eyebrow > span { width: 7px; height: 7px; display: inline-block; margin-right: 9px; border-radius: 50%; background: var(--red); }
.hero h1 { margin: 0; font-family: "Songti SC", "STSong", "Noto Serif SC", serif; font-size: clamp(44px, 4.4vw, 62px); font-weight: 900; line-height: 1.18; letter-spacing: -.045em; white-space: nowrap; }
.hero h1 em { display: inline-block; margin-top: 12px; color: var(--red); font-style: normal; }
.hero-lede { max-width: 540px; margin: 26px 0 32px; color: var(--ink-soft); font-size: 16px; line-height: 1.85; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button { min-height: 50px; display: inline-flex; align-items: center; justify-content: center; gap: 18px; padding: 0 22px; border: 1px solid transparent; border-radius: 9px; font-size: 14px; font-weight: 850; text-decoration: none; transition: transform .16s ease, box-shadow .16s ease, background .16s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--red); color: #fff; box-shadow: 0 14px 28px rgba(229, 9, 34, .2); }
.button-primary:hover { background: var(--red-dark); }
.button-secondary { border-color: var(--line); background: #fff; color: var(--ink); }
.hero-proof { display: flex; gap: 26px; margin-top: 38px; padding-top: 24px; border-top: 1px solid var(--line); }
.hero-proof div { display: flex; flex-direction: column; }
.hero-proof strong { font-size: 16px; font-weight: 900; }
.hero-proof span { color: var(--muted); font-size: 11px; }

.products { padding-top: 96px; padding-bottom: 112px; }
.product-choice-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.product-choice { position: relative; min-height: 310px; display: flex; flex-direction: column; padding: 32px 34px 30px; overflow: hidden; border: 1px solid var(--line); border-radius: 14px; color: var(--ink); text-decoration: none; transition: transform .18s ease, box-shadow .18s ease; }
.product-choice::after { content: ""; position: absolute; width: 180px; height: 180px; right: -62px; bottom: -78px; border-radius: 50%; background: rgba(255,255,255,.44); pointer-events: none; }
.product-choice:hover { transform: translateY(-4px); box-shadow: 0 22px 48px rgba(28, 25, 23, .14); }
.product-choice--exam { background: #fff0f0; border-color: rgba(229, 9, 34, .16); }
.product-choice--movie { background: #edf4f1; border-color: rgba(20, 105, 82, .16); }
.product-choice-top { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.choice-index { color: rgba(16,17,20,.28); font-size: 13px; font-weight: 900; letter-spacing: .08em; }
.choice-kicker { color: var(--red); font-size: 10px; font-weight: 900; letter-spacing: .14em; }
.product-choice--movie .choice-kicker { color: #176b56; }
.product-choice h3 { max-width: 12em; margin: 52px 0 12px; font-size: clamp(25px, 3vw, 36px); font-weight: 900; line-height: 1.2; letter-spacing: -.025em; }
.product-choice p { max-width: 34em; margin: 0; color: var(--ink-soft); font-size: 14px; line-height: 1.8; }
.choice-meta { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: auto; padding-top: 28px; color: var(--muted); font-size: 11px; font-weight: 700; }
.choice-meta strong { position: relative; z-index: 1; color: var(--ink); font-size: 12px; }
.product-choice--exam .choice-meta strong { color: var(--red); }
.product-choice--movie .choice-meta strong { color: #176b56; }

.hero-visual { position: relative; min-width: 0; padding: 34px 0 46px; }
.hero-glow { position: absolute; inset: -40px -50px -20px; background: radial-gradient(circle at center, rgba(229, 9, 34, .16), transparent 62%); filter: blur(10px); }
.browser-frame { position: relative; overflow: hidden; border: 1px solid rgba(16, 17, 20, .14); border-radius: 14px; background: #fff; box-shadow: var(--shadow); }
.browser-bar { height: 34px; display: flex; align-items: center; gap: 6px; padding: 0 12px; border-bottom: 1px solid var(--line); background: #f1f1ef; }
.browser-bar i { width: 7px; height: 7px; border-radius: 50%; background: #c9c9c6; }
.browser-bar i:first-child { background: #ff5f57; }
.browser-bar i:nth-child(2) { background: #febc2e; }
.browser-bar i:nth-child(3) { background: #28c840; }
.browser-bar span { margin-left: 7px; color: #8a8b8f; font-size: 9px; font-style: normal; }
.hero-browser { z-index: 1; transform: perspective(1200px) rotateY(-4deg) rotateX(1deg); }
.hero-browser img { width: 100%; aspect-ratio: 1024 / 522; object-fit: cover; object-position: center top; }
.floating-caption { position: absolute; z-index: 3; right: -18px; bottom: 0; width: min(330px, 70%); display: flex; flex-direction: column; padding: 18px 20px; border: 1px solid rgba(16, 17, 20, .12); border-radius: 12px; background: rgba(255, 255, 255, .95); box-shadow: 0 20px 50px rgba(16, 17, 20, .16); }
.caption-label { margin-bottom: 8px; color: var(--red); font-size: 9px; font-weight: 900; letter-spacing: .1em; }
.floating-caption strong { font-size: 13px; line-height: 1.5; }
.floating-caption small { margin-top: 4px; color: var(--muted); font-size: 10px; }

.brand-strip { border-block: 1px solid var(--line); background: #fff; }
.brand-strip .shell { min-height: 74px; display: flex; align-items: center; justify-content: center; gap: clamp(18px, 3.6vw, 48px); color: var(--ink-soft); font-size: 12px; font-weight: 750; }
.brand-strip i { width: 3px; height: 3px; border-radius: 50%; background: var(--red); }

.section-heading h2 { margin: 0; font-size: clamp(34px, 4.2vw, 54px); font-weight: 920; line-height: 1.18; letter-spacing: -.035em; }
.section-heading.centered { max-width: 680px; margin: 0 auto 76px; text-align: center; }
.section-heading.centered > p:last-child { max-width: 570px; margin: 20px auto 0; color: var(--muted); font-size: 14px; }
.product { padding-bottom: 140px; }
.product-row { display: grid; grid-template-columns: .72fr 1.45fr; align-items: center; gap: clamp(46px, 7vw, 90px); margin-top: 96px; }
.product-row.reverse { grid-template-columns: 1.45fr .72fr; }
.product-row.reverse .product-copy { order: 2; }
.product-row.reverse .product-browser { order: 1; }
.product-copy .number { color: rgba(16, 17, 20, .14); font-size: 54px; font-weight: 900; line-height: 1; }
.product-copy .kicker { margin: 16px 0 8px; color: var(--red); font-size: 11px; font-weight: 900; letter-spacing: .12em; }
.product-copy h3 { margin: 0; font-size: clamp(28px, 3vw, 40px); font-weight: 900; line-height: 1.22; letter-spacing: -.03em; }
.product-copy > p:not(.kicker) { margin: 20px 0; color: var(--ink-soft); font-size: 14px; line-height: 1.85; }
.product-copy ul { display: grid; gap: 9px; margin: 0; padding: 0; list-style: none; }
.product-copy li { position: relative; padding-left: 19px; color: var(--muted); font-size: 12px; font-weight: 650; }
.product-copy li::before { content: "✓"; position: absolute; left: 0; color: var(--red); font-weight: 900; }
.product-browser img { width: 100%; height: auto; display: block; }

.library { border-block: 1px solid rgba(255,255,255,.1); background: #111214; color: #fff; }
.library-heading { display: flex; align-items: end; justify-content: space-between; gap: 30px; margin-bottom: 48px; }
.library-heading h2 { color: #fff; }
.text-link { display: inline-flex; align-items: center; gap: 12px; padding: 11px 16px; border: 1px solid rgba(255,255,255,.16); border-radius: 999px; color: #fff; font-size: 12px; font-weight: 800; text-decoration: none; white-space: nowrap; }
.text-link span { color: #ff3d53; }
.poster-grid { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 18px; }
.poster-card { color: #fff; text-decoration: none; }
.poster-card img { width: 100%; aspect-ratio: 2 / 3; object-fit: contain; border-radius: 8px; background: #202124; box-shadow: 0 18px 38px rgba(0,0,0,.3); transition: transform .22s ease, box-shadow .22s ease; }
.poster-card:hover img { transform: translateY(-7px); box-shadow: 0 26px 48px rgba(0,0,0,.42); }
.poster-card div { padding-top: 16px; }
.poster-card span { color: #ff6374; font-size: 9px; font-weight: 850; }
.poster-card h3 { margin: 3px 0 0; font-size: 14px; font-weight: 850; }
.poster-card p { margin: 1px 0 0; overflow: hidden; color: rgba(255,255,255,.5); font-size: 10px; text-overflow: ellipsis; white-space: nowrap; }

.method-heading { display: flex; align-items: end; justify-content: space-between; gap: 50px; margin-bottom: 54px; }
.method-heading > p { max-width: none; margin: 0; color: var(--muted); font-size: 13px; white-space: nowrap; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.steps article { position: relative; min-height: 390px; padding: 18px 18px 24px; overflow: hidden; border: 1px solid var(--line); border-radius: 14px; background: #fff; }
.steps article > span { display: block; margin: 4px 4px 12px; color: var(--red); font-size: 11px; font-weight: 900; }
.step-art { width: 100%; aspect-ratio: 8 / 5; margin-bottom: 20px; border-radius: 10px; object-fit: cover; }
.steps h3 { margin: 0 8px 8px; font-size: 20px; font-weight: 900; }
.steps p { max-width: 300px; margin: 0 8px; color: var(--muted); font-size: 13px; line-height: 1.75; }

.final-cta { padding-block: 80px; background: var(--red); color: #fff; }
.final-cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 40px; }
.final-cta .eyebrow { margin-bottom: 10px; color: rgba(255,255,255,.68); }
.final-cta h2 { margin: 0; font-size: clamp(30px, 4vw, 48px); font-weight: 920; line-height: 1.2; letter-spacing: -.035em; }
.final-cta p:last-child { margin: 10px 0 0; color: rgba(255,255,255,.72); font-size: 13px; }
.button-light { flex: 0 0 auto; background: #fff; color: var(--red); box-shadow: 0 16px 36px rgba(115,0,14,.22); }
.footer { min-height: 88px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; padding-block: 28px; color: var(--muted); font-size: 12px; text-align: center; }
.footer-tagline { margin: 0; color: var(--ink-soft); }
.footer-meta { display: flex; align-items: center; justify-content: center; gap: 14px; margin: 0; }
.footer .beian { color: var(--ink-soft); letter-spacing: .04em; text-decoration: none; }
.footer .beian:hover { color: var(--ink); text-decoration: underline; }

@media (max-width: 1040px) {
  .hero { grid-template-columns: 1fr; }
  .hero-copy { max-width: 720px; }
  .hero-visual { max-width: 820px; }
  .product-choice h3 { margin-top: 38px; }
  .poster-grid { grid-template-columns: repeat(3, 1fr); gap: 34px 20px; }
  .product-row, .product-row.reverse { grid-template-columns: 1fr; }
  .product-row.reverse .product-copy, .product-row.reverse .product-browser { order: initial; }
  .product-copy { max-width: 560px; }
}

@media (max-width: 760px) {
  .shell { padding-inline: 20px; }
  .section { padding-block: 84px; }
  .nav { min-height: 64px; }
  .nav-links, .nav-login { display: none; }
  .nav-start { margin-left: auto; }
  .hero { min-height: auto; gap: 44px; padding-top: 64px; padding-bottom: 72px; }
  .hero h1 { font-size: clamp(31px, 8.8vw, 42px); }
  .hero-proof { gap: 18px; }
  .floating-caption { right: -4px; }
  .brand-strip .shell { min-height: 64px; justify-content: flex-start; overflow-x: auto; white-space: nowrap; }
  .product { padding-bottom: 96px; }
  .products { padding-top: 72px; padding-bottom: 84px; }
  .product-choice-grid { grid-template-columns: 1fr; }
  .product-choice { min-height: 280px; padding: 26px 24px 24px; }
  .product-choice h3 { margin-top: 42px; font-size: 28px; }
  .product-row { margin-top: 70px; }
  .library-heading, .method-heading { align-items: flex-start; flex-direction: column; }
  .method-heading > p { white-space: normal; }
  .steps { grid-template-columns: 1fr; }
  .steps article { min-height: auto; }
  .final-cta-inner { align-items: flex-start; flex-direction: column; }
  .footer { padding-block: 24px; }
}

@media (max-width: 520px) {
  .shell { padding-inline: 15px; }
  .brand { font-size: 15px; }
  .brand-mark { width: 38px; height: 28px; }
  .nav-start { min-height: 38px; padding-inline: 13px; }
  .nav-feedback { min-height: 32px; padding-inline: 11px; font-size: 12px; }
  .hero { padding-top: 48px; }
  .hero-lede { font-size: 14px; }
  .hero-actions { flex-direction: column; }
  .button { width: 100%; }
  .hero-proof { justify-content: space-between; gap: 8px; }
  .hero-proof strong { font-size: 14px; }
  .hero-proof span { font-size: 9px; }
  .product-choice-top { align-items: flex-start; flex-direction: column; gap: 6px; }
  .product-choice h3 { margin-top: 30px; }
  .choice-meta { align-items: flex-start; flex-direction: column; gap: 10px; }
  .browser-bar { height: 28px; }
  .floating-caption { display: none; }
  .section-heading.centered { margin-bottom: 54px; text-align: left; }
  .product-row { gap: 34px; margin-top: 60px; }
  .product-copy .number { font-size: 42px; }
  .poster-grid { grid-template-columns: repeat(2, 1fr); gap: 30px 14px; }
  .poster-card h3 { font-size: 13px; }
  .library-heading { margin-bottom: 36px; }
}