:root {
  --ink: #17202a;
  --muted: #5c6673;
  --line: #dfe5ec;
  --paper: #ffffff;
  --soft: #f5f8fc;
  --blue: #2573ff;
  --blue-dark: #1755c8;
  --coral: #ff5c5c;
  --gold: #f4c95d;
  --green: #159a78;
  --shadow: 0 18px 50px rgba(23, 32, 42, 0.12);
  --radius: 8px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
  line-height: 1.75;
  letter-spacing: 0;
}

body.menu-open {
  overflow: hidden;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

.container {
  width: min(1160px, calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(223, 229, 236, 0.9);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(16px);
}

.nav-wrap {
  display: flex;
  min-height: 72px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  min-width: max-content;
  align-items: center;
  gap: 10px;
  font-size: 19px;
  font-weight: 800;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.site-nav > a:not(.btn) {
  position: relative;
  color: #3f4854;
  font-size: 15px;
  font-weight: 650;
}

.site-nav > a:not(.btn)::after {
  position: absolute;
  right: 0;
  bottom: -9px;
  left: 0;
  height: 2px;
  background: var(--coral);
  content: "";
  opacity: 0;
  transform: scaleX(0.4);
  transition: 180ms ease;
}

.site-nav > a:hover::after,
.site-nav > a.active::after {
  opacity: 1;
  transform: scaleX(1);
}

.btn {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 0 23px;
  border: 1px solid transparent;
  border-radius: 6px;
  background: var(--blue);
  color: #ffffff;
  font-size: 15px;
  font-weight: 750;
  box-shadow: 0 10px 24px rgba(37, 115, 255, 0.22);
  transition: transform 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.btn:hover {
  background: var(--blue-dark);
  box-shadow: 0 14px 30px rgba(37, 115, 255, 0.3);
  transform: translateY(-2px);
}

.btn-outline {
  border-color: var(--ink);
  background: transparent;
  color: var(--ink);
  box-shadow: none;
}

.btn-outline:hover {
  background: var(--ink);
  color: #ffffff;
  box-shadow: none;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
  transition: 180ms ease;
}

.hero {
  position: relative;
  min-height: 0;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, #edf5ff 0%, #ffffff 72%);
}

.hero::before {
  position: absolute;
  top: 90px;
  left: 50%;
  width: 720px;
  height: 320px;
  border: 1px solid rgba(37, 115, 255, 0.15);
  border-radius: 50%;
  content: "";
  transform: translateX(-50%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  min-height: 0;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding: 42px 0 22px;
  text-align: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  color: var(--blue-dark);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
}

.eyebrow::before {
  width: 26px;
  height: 3px;
  background: var(--coral);
  content: "";
}

.hero h1,
.page-hero h1 {
  max-width: 850px;
  margin: 0;
  font-size: clamp(38px, 7vw, 76px);
  line-height: 1.08;
  letter-spacing: 0;
}

.hero-copy > p {
  max-width: 760px;
  margin: 22px auto 0;
  color: #45505d;
  font-size: 18px;
  line-height: 1.9;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-top: 26px;
}

.hero-facts {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 22px 0 0;
  padding: 0;
  color: var(--muted);
  font-size: 13px;
  list-style: none;
}

.hero-facts li::before {
  margin-right: 7px;
  color: var(--green);
  content: "●";
  font-size: 9px;
}

.hero-visuals {
  position: relative;
  display: flex;
  width: min(850px, 100%);
  min-height: 485px;
  align-items: flex-start;
  justify-content: center;
  gap: 16px;
  margin-top: 20px;
}

.hero-phone {
  position: relative;
  flex: 0 0 auto;
  width: min(190px, 24vw);
  max-width: 400px;
  height: auto;
  margin: auto 0;
  border: 7px solid var(--ink);
  border-radius: 26px;
  box-shadow: var(--shadow);
}

.hero-phone.center {
  z-index: 3;
  width: min(214px, 27vw);
  transform: none;
}

.hero-phone.left {
  z-index: 2;
  transform: translateY(28px) rotate(-7deg);
}

.hero-phone.right {
  z-index: 2;
  transform: translateY(28px) rotate(7deg);
}

.metric-band {
  border-bottom: 1px solid var(--line);
  background: var(--ink);
  color: #ffffff;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.metric {
  padding: 28px 24px;
  border-right: 1px solid rgba(255, 255, 255, 0.12);
}

.metric:last-child {
  border-right: 0;
}

.metric strong {
  display: block;
  color: var(--gold);
  font-size: 24px;
}

.metric span {
  color: #c9d0d8;
  font-size: 13px;
}

.section {
  padding: 92px 0;
}

.section-soft {
  background: var(--soft);
}

.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 32px;
  margin-bottom: 38px;
}

.section-heading h2,
.section > .container > h2,
.article-main h2 {
  margin: 0;
  font-size: clamp(27px, 4vw, 42px);
  line-height: 1.2;
  letter-spacing: 0;
}

.section-heading a {
  color: var(--blue-dark);
  font-size: 14px;
  font-weight: 750;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.feature-item {
  min-height: 230px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
}

.feature-number {
  display: inline-flex;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--ink);
  color: var(--gold);
  font-weight: 800;
}

.feature-item:nth-child(2) .feature-number,
.feature-item:nth-child(5) .feature-number {
  background: var(--coral);
  color: #ffffff;
}

.feature-item h3 {
  margin: 21px 0 9px;
  font-size: 20px;
}

.feature-item p,
.entry-card p,
.review p,
.step-body p,
.answer-card p {
  margin: 0;
  color: var(--muted);
}

.shots {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
  align-items: start;
}

.shot {
  margin: 0;
}

.shot img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border: 6px solid var(--ink);
  border-radius: 24px;
  box-shadow: 0 16px 34px rgba(23, 32, 42, 0.14);
}

.shot:nth-child(even) {
  margin-top: 42px;
}

.shot figcaption {
  padding: 14px 4px 0;
  font-size: 14px;
  font-weight: 750;
}

.entry-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}

.entry-card {
  position: relative;
  min-height: 310px;
  overflow: hidden;
  padding: 38px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
}

.entry-card::after {
  position: absolute;
  right: -36px;
  bottom: -54px;
  width: 170px;
  height: 170px;
  border: 22px solid #dbe9ff;
  border-radius: 50%;
  content: "";
}

.entry-card.coral::after {
  border-color: #ffe2e2;
}

.entry-card small {
  color: var(--coral);
  font-weight: 800;
}

.entry-card h3 {
  max-width: 430px;
  margin: 14px 0 14px;
  font-size: 28px;
  line-height: 1.35;
}

.entry-card p {
  max-width: 430px;
}

.text-link {
  position: absolute;
  bottom: 36px;
  left: 38px;
  z-index: 1;
  color: var(--blue-dark);
  font-weight: 800;
}

.reviews {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.review {
  padding: 28px;
  border-top: 4px solid var(--blue);
  background: var(--soft);
}

.review:nth-child(2) {
  border-color: var(--coral);
}

.review:nth-child(3) {
  border-color: var(--gold);
}

.review footer {
  margin-top: 20px;
  font-size: 13px;
  font-weight: 750;
}

.faq-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

details {
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--paper);
}

summary {
  position: relative;
  padding: 20px 52px 20px 22px;
  cursor: pointer;
  font-weight: 750;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  position: absolute;
  top: 50%;
  right: 20px;
  color: var(--blue);
  content: "+";
  font-size: 23px;
  transform: translateY(-50%);
}

details[open] summary::after {
  content: "−";
}

details p {
  margin: 0;
  padding: 0 22px 22px;
  color: var(--muted);
}

.download-band {
  padding: 70px 0;
  background: var(--gold);
}

.download-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 34px;
}

.download-inner h2 {
  margin: 0;
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.2;
}

.download-inner ul {
  display: flex;
  gap: 24px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.download-inner li {
  font-size: 14px;
  font-weight: 650;
}

.download-band .btn {
  min-width: 150px;
  background: var(--ink);
  box-shadow: none;
}

.site-footer {
  padding: 48px 0 24px;
  background: #10161c;
  color: #d8dde3;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr;
  gap: 60px;
}

.footer-brand {
  margin-bottom: 14px;
  color: #ffffff;
}

.site-footer h3 {
  margin: 0 0 14px;
  color: #ffffff;
  font-size: 15px;
}

.site-footer p,
.site-footer a {
  color: #9da8b4;
  font-size: 13px;
}

.footer-links {
  display: grid;
  gap: 8px;
}

.disclaimer {
  margin: 36px 0 0;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  color: #7f8b97;
  font-size: 12px;
}

.copyright {
  margin-top: 8px;
  color: #687481;
  font-size: 12px;
}

.page-hero {
  overflow: hidden;
  padding: 92px 0 68px;
  border-bottom: 1px solid var(--line);
  background: #eef5ff;
}

.page-hero.coral {
  background: #fff1f1;
}

.page-hero h1 {
  max-width: 920px;
  font-size: clamp(38px, 6vw, 66px);
}

.page-hero p {
  max-width: 760px;
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.page-meta {
  display: flex;
  gap: 20px;
  margin-top: 26px;
  color: #586474;
  font-size: 13px;
  font-weight: 700;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 290px;
  gap: 64px;
  padding: 76px 0 96px;
}

.article-main > h2:not(:first-child) {
  margin-top: 64px;
}

.article-main .lead {
  margin: 0 0 38px;
  padding: 24px;
  border-left: 5px solid var(--blue);
  background: var(--soft);
  color: #44505d;
}

.steps {
  display: grid;
  gap: 18px;
  margin-top: 30px;
}

.step {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 22px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step-index {
  display: flex;
  width: 54px;
  height: 54px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--ink);
  color: var(--gold);
  font-size: 20px;
  font-weight: 800;
}

.step-body h3 {
  margin: 0 0 8px;
  font-size: 20px;
}

.notice {
  margin-top: 28px;
  padding: 22px;
  border: 1px solid #ead277;
  background: #fff9dc;
  color: #53481c;
}

.check-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.check-list li {
  padding: 16px 18px;
  border: 1px solid var(--line);
  background: #ffffff;
}

.check-list li::before {
  margin-right: 9px;
  color: var(--green);
  content: "✓";
  font-weight: 900;
}

.article-aside {
  align-self: start;
}

.aside-box {
  position: sticky;
  top: 96px;
  padding: 25px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
}

.aside-box h2 {
  margin: 0 0 14px;
  font-size: 18px;
}

.aside-box nav {
  display: grid;
  gap: 10px;
  margin-bottom: 22px;
}

.aside-box nav a {
  color: var(--muted);
  font-size: 14px;
}

.aside-box .btn {
  width: 100%;
}

.answer-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin: 30px 0 0;
}

.answer-card {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.answer-card h3 {
  margin: 0 0 10px;
  font-size: 19px;
}

.faq-list {
  display: grid;
  gap: 12px;
  margin-top: 30px;
}

@media (max-width: 900px) {
  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: 72px;
    right: 0;
    left: 0;
    display: none;
    align-items: stretch;
    padding: 24px 20px 30px;
    border-bottom: 1px solid var(--line);
    background: #ffffff;
    flex-direction: column;
    gap: 20px;
  }

  .site-nav.open {
    display: flex;
  }

  .site-nav .btn {
    width: 100%;
  }

  .feature-grid,
  .reviews {
    grid-template-columns: repeat(2, 1fr);
  }

  .shots {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .shot:nth-child(even) {
    margin-top: 24px;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-grid > div:first-child {
    grid-column: 1 / -1;
  }

  .article-layout {
    grid-template-columns: 1fr;
  }

  .article-aside {
    order: -1;
  }

  .aside-box {
    position: static;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 28px, 1160px);
  }

  .hero {
    min-height: calc(100svh - 112px);
  }

  .hero-inner {
    min-height: calc(100svh - 112px);
    justify-content: flex-start;
    padding-top: 34px;
    padding-bottom: 16px;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 34px;
  }

  .hero-copy > p,
  .page-hero p {
    font-size: 16px;
  }

  .hero-copy > p {
    margin-top: 14px;
    line-height: 1.75;
  }

  .hero-actions,
  .download-inner,
  .download-inner ul {
    align-items: stretch;
    flex-direction: column;
  }

  .hero-actions .btn {
    width: 100%;
  }

  .hero-actions {
    margin-top: 18px;
  }

  .hero-facts {
    flex-wrap: wrap;
    gap: 6px 14px;
    margin-top: 14px;
  }

  .hero-visuals {
    height: 200px;
    min-height: 200px;
    align-items: center;
    gap: 0;
    margin-top: 20px;
  }

  .hero-phone {
    position: absolute;
    width: 106px;
    border-width: 5px;
    border-radius: 18px;
  }

  .hero-phone.center {
    width: 126px;
    transform: translateY(18px);
  }

  .hero-phone.left {
    transform: translate(-72px, 42px) rotate(-7deg);
  }

  .hero-phone.right {
    transform: translate(72px, 42px) rotate(7deg);
  }

  .metrics,
  .feature-grid,
  .entry-grid,
  .reviews,
  .faq-preview,
  .answer-grid,
  .check-list,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .metric {
    border-right: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  }

  .metric:last-child {
    border-bottom: 0;
  }

  .section {
    padding: 68px 0;
  }

  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }

  .shots {
    gap: 14px;
  }

  .shot:nth-child(even) {
    margin-top: 18px;
  }

  .shot img {
    border-width: 4px;
    border-radius: 15px;
  }

  .entry-card {
    min-height: 340px;
    padding: 28px;
  }

  .text-link {
    left: 28px;
  }

  .download-inner {
    align-items: flex-start;
  }

  .footer-grid > div:first-child {
    grid-column: auto;
  }

  .page-hero {
    padding: 70px 0 54px;
  }

  .page-meta {
    flex-wrap: wrap;
    gap: 8px 16px;
  }

  .article-layout {
    padding: 50px 0 72px;
  }

  .step {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}