:root {
  --red: #e93027;
  --red-dark: #bf1d18;
  --ink: #171a23;
  --muted: #616979;
  --soft: #f5f7fb;
  --paper: #ffffff;
  --line: #e6eaf2;
  --blue: #246bfe;
  --green: #18a058;
  --orange: #ff8b21;
  --shadow: 0 24px 70px rgba(31, 45, 78, 0.12);
  --radius: 8px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: #f7f9fd;
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  letter-spacing: 0;
}

body::selection {
  background: rgba(233, 48, 39, 0.16);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 28px;
  min-height: 74px;
  padding: 0 clamp(18px, 5vw, 72px);
  background: rgba(255, 255, 255, 0.9);
  border-bottom: 1px solid rgba(230, 234, 242, 0.8);
  backdrop-filter: blur(18px);
  transition: box-shadow 240ms ease, min-height 240ms ease;
}

.site-header.is-scrolled {
  min-height: 64px;
  box-shadow: 0 10px 30px rgba(31, 45, 78, 0.08);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  font-size: 20px;
  font-weight: 800;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  color: #fff;
  background: linear-gradient(135deg, #f03b31, #ff7c23);
  border-radius: 8px;
  font-weight: 900;
}

.main-nav {
  display: flex;
  justify-content: center;
  gap: clamp(14px, 2.5vw, 34px);
}

.main-nav a {
  color: #3b4351;
  font-size: 15px;
  font-weight: 600;
}

.main-nav a:hover {
  color: var(--red);
}

.download-link,
.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 22px;
  border-radius: var(--radius);
  font-weight: 800;
  transition: transform 220ms ease, box-shadow 220ms ease, background 220ms ease;
}

.download-link,
.primary-button {
  color: #fff;
  background: var(--red);
  box-shadow: 0 10px 24px rgba(233, 48, 39, 0.2);
}

.download-link:hover,
.primary-button:hover {
  background: var(--red-dark);
  transform: translateY(-2px);
}

.secondary-button {
  color: var(--red);
  background: #fff;
  border: 1px solid rgba(233, 48, 39, 0.22);
}

.secondary-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 34px rgba(31, 45, 78, 0.1);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.94fr) minmax(430px, 0.88fr);
  gap: clamp(28px, 6vw, 82px);
  align-items: center;
  min-height: 680px;
  padding: clamp(72px, 9vw, 126px) clamp(18px, 6vw, 92px);
  background:
    linear-gradient(120deg, rgba(255, 255, 255, 0.96), rgba(245, 248, 255, 0.86)),
    radial-gradient(circle at 82% 18%, rgba(36, 107, 254, 0.16), transparent 32%),
    radial-gradient(circle at 18% 72%, rgba(233, 48, 39, 0.1), transparent 28%);
  overflow: hidden;
}

.hero-copy {
  display: grid;
  gap: 22px;
}

.eyebrow,
.section-label {
  margin: 0;
  color: var(--red);
  font-size: 14px;
  font-weight: 800;
}

h1,
h2,
h3,
p {
  margin: 0;
}

h1 {
  max-width: 760px;
  font-size: 52px;
  line-height: 1.08;
  letter-spacing: 0;
}

h1 span {
  display: block;
}

h2 {
  font-size: 38px;
  line-height: 1.18;
  letter-spacing: 0;
}

h3 {
  font-size: 20px;
  line-height: 1.3;
}

p {
  color: var(--muted);
  line-height: 1.8;
}

.hero-lead {
  max-width: 680px;
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 8px;
}

.office-preview {
  overflow: hidden;
  border: 1px solid #dfe5f1;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
  transform: perspective(1100px) rotateY(-4deg) rotateX(2deg);
}

.window-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  height: 42px;
  padding: 0 16px;
  background: #f1f4fa;
  border-bottom: 1px solid var(--line);
}

.window-bar span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #d1d8e6;
}

.window-bar span:first-child {
  background: var(--red);
}

.window-bar strong {
  margin-left: 8px;
  color: #586173;
  font-size: 13px;
}

.ribbon {
  display: flex;
  gap: 18px;
  padding: 16px 22px;
  border-bottom: 1px solid var(--line);
}

.ribbon b {
  font-size: 13px;
}

.ribbon b:first-child {
  color: var(--red);
}

.workspace {
  display: grid;
  grid-template-columns: 130px 1fr;
  min-height: 340px;
}

.workspace aside {
  display: grid;
  align-content: start;
  gap: 8px;
  padding: 22px 14px;
  background: #fbfcff;
  border-right: 1px solid var(--line);
}

.workspace aside span {
  padding: 10px 12px;
  color: #667085;
  border-radius: var(--radius);
  font-size: 14px;
}

.workspace aside .active {
  color: var(--red);
  background: rgba(233, 48, 39, 0.08);
  font-weight: 800;
}

.workspace section {
  display: grid;
  grid-template-columns: 90px 1fr;
  align-content: center;
  gap: 22px;
  padding: 38px;
}

.doc-card {
  display: grid;
  place-items: center;
  width: 88px;
  height: 108px;
  color: #fff;
  border-radius: var(--radius);
  font-size: 46px;
  font-weight: 900;
  box-shadow: 0 16px 32px rgba(233, 48, 39, 0.2);
}

.doc-card.red {
  background: linear-gradient(135deg, #f03b31, #ff7c23);
}

.doc-lines {
  display: grid;
  align-content: center;
  gap: 14px;
}

.doc-lines strong {
  font-size: 24px;
}

.doc-lines span,
.mini-ui i {
  display: block;
  height: 12px;
  border-radius: 999px;
  background: #e9edf5;
}

.doc-lines .short {
  width: 54%;
}

.quick-links {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  width: min(1180px, calc(100vw - 36px));
  margin: -42px auto 44px;
  position: relative;
  z-index: 5;
}

.quick-links a {
  display: grid;
  gap: 8px;
  min-height: 112px;
  padding: 18px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 12px 30px rgba(31, 45, 78, 0.08);
  font-weight: 800;
}

.quick-links span {
  color: var(--red);
  font-size: 13px;
}

.content-shell {
  display: grid;
  grid-template-columns: 230px minmax(0, 1fr);
  gap: 34px;
  width: min(1180px, calc(100vw - 36px));
  margin: 0 auto;
  padding-bottom: 80px;
}

.toc {
  position: sticky;
  top: 92px;
  display: grid;
  align-content: start;
  gap: 14px;
  height: fit-content;
  padding: 22px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.toc strong {
  margin-bottom: 4px;
  font-size: 18px;
}

.toc a {
  color: #657084;
  font-size: 14px;
}

.toc a:hover {
  color: var(--red);
}

.article {
  display: grid;
  gap: 24px;
}

.article-section {
  display: grid;
  gap: 20px;
  padding: clamp(24px, 4vw, 44px);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 12px 34px rgba(31, 45, 78, 0.06);
  scroll-margin-top: 96px;
}

.intro {
  font-size: 17px;
}

.notice {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 16px;
  padding: 18px;
  background: #fff7f6;
  border: 1px solid rgba(233, 48, 39, 0.14);
  border-radius: var(--radius);
}

.notice strong {
  color: var(--red);
}

.notice span {
  color: #606978;
  line-height: 1.7;
}

.steps,
.feature-grid,
.collab-panel {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.steps article,
.feature-grid article,
.collab-panel div {
  display: grid;
  align-content: start;
  gap: 12px;
  padding: 22px;
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.trust-grid article {
  display: grid;
  align-content: start;
  gap: 12px;
  padding: 22px;
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.steps span {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  color: #fff;
  background: var(--red);
  border-radius: var(--radius);
  font-weight: 900;
}

.split-section {
  grid-template-columns: minmax(0, 1fr) minmax(300px, 0.72fr);
  align-items: center;
  gap: 28px;
}

.split-section.reverse {
  grid-template-columns: minmax(300px, 0.7fr) minmax(0, 1fr);
}

.check-list {
  display: grid;
  gap: 10px;
  padding: 0;
  margin: 6px 0 0;
  list-style: none;
}

.check-list li {
  position: relative;
  padding-left: 26px;
  color: #4c5565;
  line-height: 1.7;
}

.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 10px;
  height: 10px;
  background: var(--red);
  border-radius: 50%;
}

.mini-ui {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fbfcff;
}

.toolbar {
  display: flex;
  gap: 10px;
  padding: 14px;
  border-bottom: 1px solid var(--line);
}

.toolbar span {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-weight: 900;
}

.paper {
  display: grid;
  gap: 12px;
  margin: 22px auto;
  width: min(280px, calc(100% - 44px));
  min-height: 330px;
  padding: 34px 28px;
  background: #fff;
  border: 1px solid #edf0f6;
  box-shadow: 0 16px 34px rgba(31, 45, 78, 0.08);
}

.paper b {
  font-size: 22px;
}

.mini-ui .short {
  width: 58%;
}

.mini-ui .mid {
  width: 78%;
}

.paper div {
  height: 78px;
  margin: 8px 0;
  background: linear-gradient(135deg, rgba(233, 48, 39, 0.16), rgba(36, 107, 254, 0.12));
  border-radius: var(--radius);
}

.feature-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.app-icon {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  color: #fff;
  border-radius: var(--radius);
  font-size: 18px;
}

.app-icon.red {
  background: var(--red);
}

.app-icon.green {
  background: var(--green);
}

.app-icon.orange {
  background: var(--orange);
}

.app-icon.blue {
  background: var(--blue);
  font-size: 14px;
}

.save-card {
  display: grid;
  gap: 12px;
  padding: 26px;
  background: linear-gradient(135deg, #1f2d4e, #32466d);
  border-radius: var(--radius);
  color: #fff;
}

.save-card strong {
  margin-bottom: 8px;
  font-size: 22px;
}

.save-card span {
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius);
}

.faq details {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--soft);
}

.faq summary {
  cursor: pointer;
  padding: 18px 20px;
  font-weight: 800;
}

.faq details p {
  padding: 0 20px 20px;
}

.cta-section {
  display: grid;
  justify-items: start;
  gap: 16px;
  padding: clamp(34px, 5vw, 56px);
  color: #fff;
  background:
    linear-gradient(135deg, rgba(233, 48, 39, 0.94), rgba(255, 124, 35, 0.92)),
    #e93027;
  border-radius: var(--radius);
  box-shadow: 0 24px 60px rgba(233, 48, 39, 0.22);
}

.cta-section p {
  color: rgba(255, 255, 255, 0.84);
}

.cta-section .primary-button {
  color: var(--red);
  background: #fff;
  box-shadow: none;
}

.policy-page {
  width: min(1040px, calc(100vw - 36px));
  margin: 0 auto;
  padding: clamp(52px, 8vw, 92px) 0 80px;
}

.policy-hero {
  display: grid;
  gap: 18px;
  margin-bottom: 24px;
  padding: clamp(30px, 5vw, 54px);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 12px 34px rgba(31, 45, 78, 0.06);
}

.policy-hero h1 {
  font-size: clamp(36px, 5vw, 52px);
}

.policy-hero p {
  max-width: 780px;
  font-size: 17px;
}

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

.policy-grid article {
  display: grid;
  align-content: start;
  gap: 14px;
  padding: clamp(24px, 4vw, 36px);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.policy-grid h2 {
  font-size: 26px;
}

.info-list {
  display: grid;
  gap: 12px;
  margin: 0;
}

.info-list div {
  display: grid;
  gap: 5px;
  padding: 14px;
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.info-list dt {
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}

.info-list dd {
  margin: 0;
  color: var(--ink);
  font-weight: 800;
  overflow-wrap: anywhere;
}

.info-list a {
  color: var(--red);
}

.minor-note {
  padding: 14px 16px;
  color: #6a4b15;
  background: #fff8e5;
  border: 1px solid #f3dda0;
  border-radius: var(--radius);
}

.not-found-page {
  min-height: calc(100vh - 210px);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 20px;
  padding: 34px clamp(18px, 6vw, 92px);
  background: #171a23;
  color: #fff;
}

.site-footer p {
  color: rgba(255, 255, 255, 0.66);
}

.site-footer a {
  color: #fff;
  font-weight: 800;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 14px 20px;
}

@media (max-width: 1080px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .main-nav {
    grid-column: 1 / -1;
    justify-content: start;
    overflow-x: auto;
    padding-bottom: 12px;
  }

  .hero,
  .content-shell,
  .split-section,
  .split-section.reverse {
    grid-template-columns: 1fr;
  }

  .toc {
    position: static;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .toc strong {
    grid-column: 1 / -1;
  }

  .quick-links,
  .steps,
  .feature-grid,
  .collab-panel,
  .trust-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .office-preview {
    transform: none;
  }
}

@media (max-width: 700px) {
  .site-header {
    gap: 14px;
    padding-inline: 14px;
  }

  .brand span:last-child {
    display: none;
  }

  .download-link {
    padding: 0 16px;
  }

  .hero {
    min-height: auto;
    padding: 52px 16px 86px;
  }

  h1 {
    font-size: 38px;
  }

  h2 {
    font-size: 30px;
  }

  .hero-lead {
    font-size: 16px;
  }

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

  .workspace aside {
    display: flex;
    overflow-x: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .workspace section {
    grid-template-columns: 1fr;
    padding: 24px;
  }

  .quick-links,
  .steps,
  .feature-grid,
  .collab-panel,
  .trust-grid,
  .toc,
  .notice {
    grid-template-columns: 1fr;
  }

  .quick-links {
    margin-top: -34px;
  }

  .article-section {
    padding: 22px;
  }

  .site-footer {
    display: grid;
  }

  .footer-nav {
    justify-content: flex-start;
  }
}