/* ===== Academic site — Minimal Mistakes 스타일 ===== */
:root {
  --text: #494e52;
  --heading: #313436;
  --muted: #7a8288;
  --link: #52adc8;
  --accent: #8b1e1e;          /* 버튼 색 (Texas A&M maroon 계열) */
  --border: #f2f3f3;
  --bg: #ffffff;
  --code-bg: #fafafa;
}

* { box-sizing: border-box; }

html { font-size: 16px; }
@media (min-width: 1024px) { html { font-size: 17px; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Roboto", "Segoe UI",
               "Helvetica Neue", "Lucida Grande", Arial, sans-serif;
  line-height: 1.5;
}

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ===== 상단 네비게이션 ===== */
.masthead {
  border-bottom: 1px solid var(--border);
  background: #fff;
  position: sticky; top: 0; z-index: 10;
}
.masthead__inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 1em 1.5em;
  display: flex; align-items: center; gap: 2.5em;
}
.site-title {
  font-weight: 700; color: var(--heading); font-size: 1rem; white-space: nowrap;
}
.site-title:hover { text-decoration: none; }
.nav-links { display: flex; gap: 1.5em; margin: 0; padding: 0; list-style: none; }
.nav-links a { color: var(--muted); font-size: .95rem; }
.nav-links a.active, .nav-links a:hover { color: var(--heading); text-decoration: none; }

/* ===== 레이아웃: 사이드바 + 본문 ===== */
.page {
  max-width: 1280px;
  margin: 0 auto;
  padding: 2em 1.5em 4em;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 3em;
}
@media (max-width: 800px) {
  .page { grid-template-columns: 1fr; gap: 1.5em; padding-top: 1.5em; }
}

/* ===== 사이드바 (프로필) ===== */
.sidebar { font-size: .8rem; }
@media (min-width: 801px) { .sidebar { position: sticky; top: 5em; align-self: start; } }

.author__avatar img {
  width: 160px; height: 160px; object-fit: cover;
  border-radius: 50%; border: 1px solid #ddd; padding: 4px; display: block;
}
.author__name { margin: .8em 0 .2em; font-size: 1.1rem; font-weight: 700; color: var(--heading); }
.author__bio { margin: 0 0 1em; color: var(--text); }
.author__links { list-style: none; margin: 0; padding: 0; }
.author__links li { margin: .45em 0; }
.author__links a, .author__links span { color: var(--text); }
.author__links i { width: 1.2em; text-align: center; margin-right: .35em; color: var(--heading); }

@media (max-width: 800px) {
  .sidebar { display: flex; gap: 1.2em; align-items: center; flex-wrap: wrap; }
  .author__avatar img { width: 100px; height: 100px; }
  .author__links { display: flex; flex-wrap: wrap; gap: .3em 1em; }
  .author__links li { margin: 0; }
}

/* ===== 본문 ===== */
.content { max-width: 760px; min-width: 0; }
.content h1 { font-size: 1.6rem; color: var(--heading); margin: 0 0 .8em; }
.content h2 {
  font-size: 1.35rem; color: var(--heading);
  margin: 0 0 .8em; padding-bottom: .4em;
}
.content h2 + * { margin-top: 0; }
.content section { margin-bottom: 2.5em; }
.content p { margin: 0 0 1em; }

/* 논문 항목 */
.paper { margin-bottom: 1.6em; }
.paper__title { margin: 0 0 .5em; }
.paper__title em { font-style: italic; }

.btns { display: flex; flex-wrap: wrap; gap: .4em; }
.btn {
  display: inline-block;
  font-size: .78rem; line-height: 1.4;
  padding: .25em .55em;
  border: 1px solid var(--accent);
  border-radius: 3px;
  color: var(--accent); background: #fff;
  cursor: pointer; font-family: inherit;
}
.btn:hover { background: var(--accent); color: #fff; text-decoration: none; }
.btn[aria-expanded="true"] { background: var(--accent); color: #fff; }

.abstract {
  display: none;
  margin-top: .7em;
  padding: .8em 1em;
  background: var(--code-bg);
  border-left: 3px solid var(--accent);
  font-size: .9rem;
}
.abstract.open { display: block; }

.paper__note { margin: -.3em 0 .5em; font-size: .85rem; color: var(--muted); }
.muted { color: var(--muted); font-weight: 400; }

/* Teaching 페이지 */
.course { margin-bottom: 1.1em; }
.content .course__title { margin: 0; }
.content .course__term { margin: .1em 0 0; font-size: .85rem; color: var(--muted); }

/* 일반 리스트 */
.plain-list { padding-left: 1.2em; }
.plain-list li { margin-bottom: .5em; }

/* CV 페이지 PDF 뷰어 */
.cv-frame {
  width: 100%; height: 80vh;
  border: 1px solid #ddd; border-radius: 4px;
}

footer {
  text-align: center; font-size: .75rem; color: var(--muted);
  padding: 2em 1em; border-top: 1px solid var(--border);
}

@media (max-width: 480px) {
  .masthead__inner { flex-wrap: wrap; gap: .4em 1.2em; padding: .8em 1em; }
  .nav-links { flex-wrap: wrap; gap: .3em 1em; }
  .nav-links a { font-size: .9rem; }
}

/* Contact 페이지 */
.content .contact { margin-bottom: 1.8em; }
.content .contact h2 { font-size: 1.1rem; margin-bottom: .4em; }
.content .contact h2 i { width: 1.2em; color: var(--accent); }
.content address { font-style: normal; line-height: 1.6; }