:root {
  --blue: #2a6cb5;
  --blue-deep: #1d4f86;
  --ink: #1c2430;
  --muted: #5c6778;
  --paper: #f4f7fb;
  --sheet: #ffffff;
  --line: #e2e8f0;
  --footer: #12161c;
  --wide: 64rem;
  --text: 42rem;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--paper);
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  font-size: 1.0625rem;
  line-height: 1.75;
}

a {
  color: var(--blue-deep);
  text-underline-offset: 0.18em;
}

img {
  max-width: 100%;
}

.site-header {
  position: relative;
  z-index: 2;
  background: linear-gradient(180deg, #3b82c4 0%, var(--blue) 100%);
  color: #fff;
}

.bar,
.site-footer .bar,
main {
  width: min(var(--wide), calc(100% - 3rem));
  margin-inline: auto;
}

.bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 4.25rem;
}

.mark {
  color: #fff;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-decoration: none;
}

nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.35rem 1.25rem;
  font-size: 0.95rem;
}

nav a {
  color: rgba(255, 255, 255, 0.88);
  text-decoration: none;
  white-space: nowrap;
  padding: 0.2rem 0;
}

nav a[aria-current="page"] {
  color: #fff;
  box-shadow: inset 0 -2px 0 #fff;
}

.hero {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 18rem;
  color: #fff;
  text-align: center;
  overflow: hidden;
}

.hero img,
.page-banner img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero .veil {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(18, 58, 112, 0.28), rgba(18, 58, 112, 0.42));
}

.hero-copy,
.page-banner h1 {
  position: relative;
  z-index: 1;
  margin: 0;
  padding: 3rem 1.5rem;
  text-shadow: 0 1px 2px rgba(12, 32, 64, 0.35);
}

.hero h1 {
  margin: 0;
  font-size: 2.35rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  line-height: 1.35;
}

.hero p {
  margin: 0.75rem 0 0;
  letter-spacing: 0.28em;
  font-size: 0.95rem;
}

.page-banner {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 11rem;
  color: #fff;
  text-align: center;
  overflow: hidden;
}

.page-banner .veil {
  position: absolute;
  inset: 0;
  background: rgba(16, 48, 96, 0.28);
}

.page-banner h1 {
  font-size: 2rem;
  font-weight: 600;
  letter-spacing: 0.14em;
}

main {
  flex: 1;
  padding: 2.75rem 0 3.5rem;
}

main.prose {
  width: min(var(--text), calc(100% - 3rem));
}

.intro {
  max-width: 40rem;
  margin: 0 auto 2.25rem;
  text-align: center;
  color: var(--muted);
}

.intro p {
  margin: 0.4rem 0;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.cards a {
  display: block;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--sheet);
  color: var(--ink);
  text-decoration: none;
}

.cards img {
  display: block;
  width: 100%;
  height: 11.5rem;
  object-fit: cover;
}

.cards span {
  display: block;
  padding: 0.75rem 0.5rem 0.9rem;
  text-align: center;
  letter-spacing: 0.06em;
}

.cards a:hover span {
  color: var(--blue);
}

#app {
  margin-top: 2.75rem;
  text-align: center;
}

#app h2 {
  margin: 0 0 0.4rem;
  font-size: 1.35rem;
}

#app p {
  margin: 0;
  color: var(--muted);
}

.downloads {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 1.1rem;
}

.button {
  display: inline-block;
  padding: 0.55rem 1.1rem;
  border: 1px solid var(--blue);
  background: var(--blue);
  color: #fff;
  text-decoration: none;
  font-size: 1rem;
}

.button:hover {
  background: var(--blue-deep);
  border-color: var(--blue-deep);
  color: #fff;
}

.button-quiet {
  background: transparent;
  color: var(--blue-deep);
}

.button-quiet:hover {
  background: transparent;
  color: var(--blue);
}

#wechat-tip {
  margin-top: 0.8rem;
  color: var(--blue-deep);
}

h1 {
  margin: 0 0 0.8rem;
  font-size: 2rem;
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: 0.04em;
}

h2 {
  margin: 2.2rem 0 0.55rem;
  font-size: 1.28rem;
  font-weight: 600;
  line-height: 1.4;
}

.lede {
  margin-top: 0;
  color: var(--muted);
}

.features {
  padding-left: 1.3rem;
}

.features li + li {
  margin-top: 0.35rem;
}

.questions {
  padding-left: 1.3rem;
}

.site-footer {
  background: var(--footer);
  color: #c5ccd6;
  font-size: 0.92rem;
}

.site-footer .bar {
  display: block;
  padding: 1.6rem 0 1.8rem;
  text-align: center;
}

.site-footer p {
  margin: 0.25rem 0;
}

.site-footer a {
  color: #d5dce6;
}

.footer-links,
.footer-beian {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.35rem 1.25rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.98rem;
}

th,
td {
  padding: 0.55rem 0.7rem;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

th {
  font-weight: 600;
  white-space: nowrap;
}

@media (max-width: 960px) {
  .site-header .bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.35rem;
    padding: 0.85rem 0;
  }

  .site-header nav {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.15rem;
  }
}

@media (max-width: 720px) {
  .bar,
  .site-footer .bar,
  main {
    width: min(100% - 2rem, var(--wide));
  }

  .bar {
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 0.35rem;
    padding: 0.9rem 0;
  }

  nav {
    flex-direction: column;
    gap: 0.2rem;
  }

  .hero {
    min-height: 14rem;
  }

  .hero h1,
  .page-banner h1 {
    font-size: 1.55rem;
    letter-spacing: 0.06em;
  }

  .hero p {
    letter-spacing: 0.12em;
  }

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