* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Malgun Gothic", "Apple SD Gothic Neo", Arial, sans-serif;
  background: #f6f7fb;
  color: #1f2937;
  line-height: 1.75;
}
header, main, footer {
  max-width: 940px;
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 22px;
  padding-bottom: 22px;
  border-bottom: 1px solid #e5e7eb;
  background: #fff;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #111827;
  font-weight: 800;
  text-decoration: none;
}
.brand-mark {
  display: inline-flex;
  width: 30px;
  height: 30px;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  background: #4f46e5;
  color: #fff;
}
.top-links a, .back-link {
  color: #4f46e5;
  font-size: 14px;
  text-decoration: none;
  font-weight: 700;
  margin-left: 14px;
}
main {
  padding-top: 42px;
  padding-bottom: 72px;
  background: #fff;
}
h1 {
  margin: 0 0 12px;
  font-size: 34px;
  line-height: 1.25;
  color: #111827;
}
h2 {
  margin: 42px 0 12px;
  padding-left: 12px;
  border-left: 4px solid #4f46e5;
  color: #111827;
  font-size: 23px;
  line-height: 1.35;
}
h3 { margin: 26px 0 8px; color: #111827; }
.lead {
  margin: 0 0 30px;
  max-width: 760px;
  color: #4b5563;
  font-size: 17px;
}
p, li { font-size: 15px; }
ul, ol { padding-left: 24px; }
li { margin: 8px 0; }
table {
  width: 100%;
  margin: 18px 0;
  border-collapse: collapse;
  font-size: 14px;
}
th, td {
  border: 1px solid #d1d5db;
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}
th { background: #eef2ff; color: #111827; }
.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 16px;
  margin: 30px 0 42px;
}
.guide-card {
  display: block;
  min-height: 170px;
  padding: 18px;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  background: #f9fafb;
  color: inherit;
  text-decoration: none;
}
.guide-card:hover { border-color: #a5b4fc; background: #f5f7ff; }
.guide-card strong {
  display: block;
  margin-bottom: 8px;
  color: #111827;
  font-size: 17px;
}
.guide-card span { color: #4b5563; font-size: 14px; }
.note {
  margin: 18px 0;
  padding: 14px 16px;
  border-left: 4px solid #10b981;
  background: #ecfdf5;
  color: #064e3b;
  border-radius: 6px;
}
.related {
  margin-top: 48px;
  padding: 20px;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  background: #f9fafb;
}
.related a {
  display: inline-block;
  margin: 4px 14px 4px 0;
  color: #4338ca;
  font-weight: 700;
  text-decoration: none;
}
.cta {
  margin-top: 42px;
  padding: 24px;
  border-radius: 8px;
  background: #eef2ff;
  text-align: center;
}
.cta a {
  display: inline-block;
  margin-top: 12px;
  padding: 11px 22px;
  border-radius: 6px;
  background: #4f46e5;
  color: #fff;
  text-decoration: none;
  font-weight: 800;
}
footer {
  padding-top: 22px;
  padding-bottom: 28px;
  color: #6b7280;
  font-size: 13px;
  background: #fff;
  border-top: 1px solid #e5e7eb;
}
@media (max-width: 640px) {
  header { align-items: flex-start; gap: 12px; flex-direction: column; }
  .top-links a { margin-left: 0; margin-right: 14px; }
  h1 { font-size: 29px; }
}