:root {
  --page: #f1eee5;
  --paper: #fffdf7;
  --ink: #294653;
  --muted: #71817f;
  --line: #d8dfd7;
  --pale: #edf2eb;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  background: var(--page);
  color: var(--ink);
  font:
    16px/1.8 system-ui,
    -apple-system,
    "PingFang SC",
    "Microsoft YaHei",
    sans-serif;
}
a {
  color: inherit;
  text-underline-offset: 5px;
  text-decoration-thickness: 1px;
}
.site-header {
  max-width: 1060px;
  margin: auto;
  padding: 26px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 23px;
  font-weight: 700;
}
.brand img {
  border-radius: 10px;
}
.header-actions {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 13px;
}
.header-actions > a {
  text-decoration: none;
}
main {
  padding: 18px 24px 36px;
}
.letter {
  max-width: 820px;
  margin: auto;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 64px 76px 42px;
  box-shadow: 0 12px 45px #29465307;
}
.letter-header {
  padding-bottom: 30px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}
.eyebrow {
  font-size: 12px;
  color: var(--muted);
  letter-spacing: 0.18em;
  margin: 0 0 18px;
}
h1 {
  font-family: "Songti SC", "Noto Serif CJK SC", serif;
  font-size: clamp(27px, 4.8vw, 36px);
  line-height: 1.5;
  font-weight: 600;
  letter-spacing: 0.03em;
  margin: 0 0 14px;
}
.subtitle {
  color: var(--muted);
  font-size: 14px;
  margin: 0;
}
.letter-body {
  line-height: 2.05;
  letter-spacing: 0.025em;
}
.letter-body > p {
  margin: 0 0 23px;
}
.salutation {
  font-family: "Songti SC", serif;
  font-size: 20px;
}
strong {
  font-weight: 600;
}
hr {
  width: 48px;
  border: 0;
  border-top: 1px solid var(--line);
  margin: 36px 0;
}
.promise {
  background: var(--pale);
  border-left: 3px solid var(--ink);
  padding: 22px 25px;
  margin: 34px 0;
}
.promise p {
  margin: 0 0 14px;
}
.promise p:last-child {
  margin-bottom: 0;
  font-size: 14px;
}
.promise .promise-label {
  font-size: 12px;
  color: var(--muted);
  letter-spacing: 0.12em;
}
.signature {
  margin-top: 38px;
  text-align: right;
}
.signature p {
  margin: 0;
  font-family: "Songti SC", serif;
  font-size: 20px;
}
.signature time {
  font-size: 12px;
  color: var(--muted);
}
.letter-footer {
  border-top: 1px solid var(--line);
  padding-top: 26px;
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px 24px;
  font-size: 13px;
}
.primary-link {
  font-weight: 600;
}
.closing {
  text-align: center;
  color: var(--muted);
  font-size: 12px;
  margin: 28px 0 0;
}
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 5px;
}
@media (max-width: 620px) {
  .site-header {
    padding: 18px;
  }
  .header-actions {
    gap: 12px;
  }
  .brand {
    font-size: 20px;
    gap: 7px;
  }
  .brand img {
    width: 30px;
    height: 30px;
  }
  main {
    padding: 6px 12px 28px;
  }
  .letter {
    padding: 35px 24px 28px;
  }
  .letter-header {
    margin-bottom: 28px;
    padding-bottom: 24px;
  }
  .letter-body {
    font-size: 15px;
    line-height: 2;
  }
  .promise {
    padding: 20px 18px;
  }
  .letter-footer {
    gap: 16px;
  }
}
@media print {
  .site-header,
  .letter-footer,
  .closing {
    display: none;
  }
  body,
  .letter {
    background: white;
    color: black;
  }
  main,
  .letter {
    padding: 0;
    border: 0;
    box-shadow: none;
  }
  .promise {
    break-inside: avoid;
  }
}

.product-language {
  font: inherit;
  color: inherit;
  background: transparent;
  border: 1px solid currentColor;
  border-radius: 10px;
  padding: 7px 10px;
  max-width: 150px;
  min-width: 0;
}
@media (max-width: 600px) {
  .header-actions {
    flex-wrap: wrap;
    justify-content: flex-end;
  }
  .product-language {
    font-size: 13px;
    max-width: 125px;
  }
  .heading h2 {
    overflow-wrap: anywhere;
  }
}