* { box-sizing: border-box; margin: 0; }

html {
  background: #fff;
  color: #1a1a1a;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI",
    "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  line-height: 1.7;
}

main { max-width: 700px; margin: 0 auto; padding: 5rem 1.25rem; }

.home-header { text-align: center; margin-bottom: 0; }
.home-header img { margin-bottom: 1rem; }
.home-header h1 { font-size: 2rem; font-weight: 700; margin: 0; }

.lang-switch { display: flex; justify-content: center; gap: 0.5rem; margin: 2rem 0; }
.lang-switch button {
  background: none; border: none; padding: 0.35rem 0.85rem;
  cursor: pointer; font-size: 0.85rem; color: #999;
  font-family: inherit;
}
.lang-switch button.active { color: #1a1a1a; border-bottom: 1.5px solid #1a1a1a; }

body[data-lang="en"] li[data-lang="ko"] { display: none; }
body[data-lang="ko"] li[data-lang="en"] { display: none; }

.page-footer {
  text-align: center;
  color: #999;
  font-size: 0.8rem;
  margin-top: 5rem;
  padding: 0 1.25rem 2rem;
  line-height: 1.5;
}
.page-footer .code-line { font-family: ui-monospace, "SF Mono", Menlo, monospace; margin-bottom: 0.35rem; }
.page-footer .explain { max-width: 520px; margin: 0 auto; font-size: 0.75rem; color: #a3a3a3; }
body[data-lang="ko"] .explain-en { display: none; }
body[data-lang="en"] .explain-ko { display: none; }

a { color: #1a1a1a; }
a:hover { color: #666; }
h1 { font-size: 2rem; margin-bottom: 0.5rem; }
h2 { margin-top: 2rem; margin-bottom: 0.5rem; }

.post-frame {
  max-width: 1100px;
  margin: 0 auto;
  padding: 5rem 1.25rem;
  display: grid;
  grid-template-columns: minmax(0, 1fr) min(700px, 100%) minmax(0, 1fr);
  column-gap: 2rem;
  align-items: start;
}
.post-frame article { grid-column: 2; min-width: 0; }
.post-nav {
  grid-column: 1;
  justify-self: end;
  position: sticky;
  top: 2rem;
  font-size: 0.85rem;
}
.post-nav a { color: #737373; white-space: nowrap; }
.post-nav a:hover { color: #1a1a1a; }

@media (max-width: 900px) {
  .post-frame {
    grid-template-columns: 1fr;
    padding: 2rem 1.25rem;
    column-gap: 0;
  }
  .post-nav {
    grid-column: 1;
    justify-self: start;
    position: static;
    margin-bottom: 1.5rem;
  }
  .post-frame article { grid-column: 1; }
}

.post-header { margin-bottom: 2.5rem; }
.post-header h1 { font-size: 2rem; line-height: 1.3; margin-bottom: 1.5rem; }
.post-meta {
  border-top: 1px solid #d4d4d4;
  padding-top: 0.6rem;
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  color: #999;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

article { margin-top: 0; }
article p { margin: 1em 0; }
article ul, article ol { padding-left: 1.5em; }
code { background: #f5f5f5; padding: 0.15em 0.4em; border-radius: 3px; font-size: 0.9em; }
pre { background: #fafafa; border: 1px solid #eee; padding: 1em; border-radius: 6px; overflow-x: auto; }
pre code { background: none; padding: 0; }
blockquote { border-left: 3px solid #ccc; padding-left: 1em; color: #666; font-style: italic; }
table { border-collapse: collapse; width: 100%; margin: 1em 0; }
th, td { border: 1px solid #e5e5e5; padding: 0.5em 0.75em; text-align: left; }
th { background: #fafafa; }

.post-list { list-style: none; padding: 0; max-width: 480px; margin: 0 auto; }
.post-list li { margin: 0.75rem 0; }
.post-list li a { display: block; text-decoration: none; color: #1a1a1a; }
.post-list li a:hover { color: #666; }
.post-list .date { color: #999; font-size: 0.85rem; display: inline-block; width: 6.5rem; }

img { max-width: 100%; height: auto; border-radius: 6px; }
figure { margin: 1.5em 0; }
figure img { display: block; }
figcaption { color: #999; font-size: 0.85rem; font-style: italic; margin-top: 0.5rem; }
hr { border: none; border-top: 1px solid #e5e5e5; margin: 2em 0; }
iframe { border: none; border-radius: 6px; margin: 1em 0; }

.bar-chart { margin: 1em 0; }
.bar-row { display: flex; align-items: center; gap: 0.5rem; margin: 0.4rem 0; }
.bar-label { width: 4rem; text-align: right; font-size: 0.85rem; color: #999; }
.bar { background: #1a1a1a; color: #fff; font-size: 0.75rem; font-weight: 600; padding: 0.3rem 0.5rem; border-radius: 4px; }