/* ---------------------------------------------------------------
   (Danny) To Eun Kim — personal site
   Single column, minimal. Accent colors carried over from the
   previous jonbarron-template site for visual continuity.
   --------------------------------------------------------------- */

:root {
  --bg:        #ffffff;
  --fg:        #1a1a1a;
  --fg-muted:  #666666;
  --rule:      #e4e4e4;
  --link:      #1772d0;
  --link-hover:#f09228;
  --chip-bg:   #f4f4f4;
  --chip-on:   #1772d0;
  --measure:   760px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:        #15171a;
    --fg:        #e6e6e6;
    --fg-muted:  #9aa0a6;
    --rule:      #2c2f34;
    --link:      #5fa8f5;
    --link-hover:#f0a355;
    --chip-bg:   #23262b;
    --chip-on:   #5fa8f5;
  }
  /* Paper thumbnails are mostly white-background figures. */
  .pub__thumb img { filter: brightness(.92); }
}

*, *::before, *::after { box-sizing: border-box; }

/* The filter script hides entries via the `hidden` attribute. Author rules like
   `.pub { display: flex }` outrank the UA stylesheet's [hidden] rule, so re-assert
   it here or hidden elements stay visible. */
[hidden] { display: none !important; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
               Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
}

.wrap {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
}

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

img { max-width: 100%; height: auto; }

h1, h2, h3 { line-height: 1.25; font-weight: 700; }
h1 { font-size: 1.7rem; margin: 0 0 .3rem; }
h2 {
  font-size: 1.3rem;
  margin: 2.5rem 0 .9rem;
  padding-bottom: .35rem;
  border-bottom: 1px solid var(--rule);
}
h3 { font-size: 1.02rem; margin: 1.6rem 0 .35rem; }
/* Small unbolded aside sitting beside a section heading. */
.heading-note {
  font-weight: 400;
  font-size: .85rem;
  color: var(--fg-muted);
  margin-left: .5rem;
}
p  { margin: 0 0 1rem; }

/* --- Nav ------------------------------------------------------- */
.site-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: .5rem 1rem;
  padding: 1.5rem 0 .8rem;
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--rule);
}
.site-nav__name {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--fg);
}
.site-nav__name:hover { color: var(--link-hover); text-decoration: none; }
.site-nav__links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.site-nav__links a.is-current {
  color: var(--fg);
  border-bottom: 2px solid var(--link);
  padding-bottom: 1px;
}

/* --- Home header ----------------------------------------------- */
.profile {
  display: flex;
  gap: 1.75rem;
  align-items: flex-start;
  margin-bottom: 2rem;
}
.profile__photo {
  flex: 0 0 180px;
  width: 180px;
  border-radius: 4px;
}
.profile__body { flex: 1 1 auto; min-width: 0; }
.profile__name { font-size: 1.7rem; font-weight: 700; margin: 0; }
.profile__meta { color: var(--fg-muted); margin: .2rem 0 .7rem; }
.profile__links {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
}
/* Text links keep normal link styling; only the brand marks are muted. */
.profile__links a.icon-link {
  display: inline-flex;
  color: var(--fg-muted);
  line-height: 0;
}
.profile__links a.icon-link:hover { color: var(--link-hover); }
.icon {
  width: 22px;
  height: 22px;
  fill: currentColor;   /* inherits the link colour, so dark mode just works */
}

/* --- Page header ----------------------------------------------- */
.page-head { margin-bottom: 1.5rem; }
.page-head__sub { color: var(--fg-muted); margin: .25rem 0 0; }

/* --- News ------------------------------------------------------ */
.news { list-style: none; margin: 0; padding: 0; }
.news li {
  display: flex;
  gap: .9rem;
  padding: .3rem 0;
  align-items: baseline;
}
.news__date {
  flex: 0 0 5.5rem;
  color: var(--fg-muted);
  font-variant-numeric: tabular-nums;
  font-size: .88rem;
}
.news__text { flex: 1 1 auto; min-width: 0; }
.news__text p { margin: 0; }
details.news-more,
details.bio-more { margin-top: .5rem; }
details.news-more > summary,
details.bio-more > summary {
  cursor: pointer;
  color: var(--link);
  width: fit-content;
}
details.news-more > summary:hover,
details.bio-more > summary:hover { color: var(--link-hover); }
details.news-more[open] > summary,
details.bio-more[open] > summary { margin-bottom: .3rem; }

/* --- Publications ---------------------------------------------- */
.pub {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  padding: 1.1rem 0;
  border-bottom: 1px solid var(--rule);
}
.pub:last-child { border-bottom: 0; }
.pub__thumb { flex: 0 0 180px; }
.pub__thumb img { width: 180px; border-radius: 3px; display: block; }
.pub__body { flex: 1 1 auto; min-width: 0; }
.pub__title { font-weight: 700; }
.pub__authors { margin: .15rem 0 0; }
.pub__venue { color: var(--fg-muted); font-style: italic; margin: .15rem 0 0; }
.pub__award { margin: .15rem 0 0; }
.pub__links { margin: .3rem 0 0; }
.pub__tldr { margin: .5rem 0 0; color: var(--fg-muted); font-size: .95rem; }
.pub__note { font-size: .88rem; color: var(--fg-muted); }

.year-head {
  font-size: 1.1rem;
  margin: 2rem 0 .25rem;
  padding-bottom: .3rem;
  border-bottom: 1px solid var(--rule);
  color: var(--fg-muted);
}

/* --- Paper pills (research section) ----------------------------- */
.paper-links {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  /* Pull up against the description it belongs to (the preceding <p> carries a
     1rem bottom margin) and leave clear air before the next research area. */
  margin: -.55rem 0 1.9rem;
}
.paper-links a {
  display: inline-block;
  padding: .18rem .65rem;
  border: 1px solid var(--rule);
  border-radius: 999px;
  background: var(--chip-bg);
  color: var(--fg-muted);
  font-size: .82rem;
  line-height: 1.5;
}
.paper-links a:hover,
.paper-links a:focus {
  border-color: var(--link);
  color: var(--link);
  text-decoration: none;
}

/* --- Filters --------------------------------------------------- */
.filters {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  align-items: center;
  margin: 0 0 1rem;
}
.chip {
  font: inherit;
  font-size: .88rem;
  padding: .28rem .7rem;
  border: 1px solid var(--rule);
  border-radius: 999px;
  background: var(--chip-bg);
  color: var(--fg);
  cursor: pointer;
}
.chip:hover { border-color: var(--chip-on); }
.chip[aria-pressed="true"] {
  background: var(--chip-on);
  border-color: var(--chip-on);
  color: #fff;
}
.filters select {
  font: inherit;
  font-size: .88rem;
  padding: .28rem .5rem;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--chip-bg);
  color: var(--fg);
}
.filter-count { color: var(--fg-muted); font-size: .88rem; margin: 0 0 1rem; }

/* --- Generic lists --------------------------------------------- */
.tight { margin: .25rem 0 1rem; padding-left: 1.2rem; }
.tight li { margin: .15rem 0; }
.dated { display: flex; gap: .9rem; }
.dated__when { flex: 0 0 8rem; color: var(--fg-muted); font-size: .9rem; }

/* --- Footer ---------------------------------------------------- */
.site-footer {
  margin-top: 3rem;
  padding-top: 1.2rem;
  border-top: 1px solid var(--rule);
  text-align: center;
  font-size: .88rem;
  color: var(--fg-muted);
}
.site-footer p { margin: 0 0 .4rem; }
.site-footer__credit { font-size: .82rem; }

/* --- Narrow screens -------------------------------------------- */
@media (max-width: 600px) {
  /* Paper thumbnails are decorative; drop them rather than shrink them.
     Same call the previous site made. */
  .pub__thumb { display: none; }
  .profile { flex-direction: column; gap: 1rem; }
  .profile__photo { flex-basis: auto; width: 150px; }
  .news li { flex-direction: column; gap: 0; }
  .news__date { flex-basis: auto; }
  .dated { flex-direction: column; gap: 0; }
  .dated__when { flex-basis: auto; }
  h1, .profile__name { font-size: 1.45rem; }
}

@media (max-width: 520px) {
  .site-nav { flex-direction: column; align-items: flex-start; }
}

/* --- Utilities -------------------------------------------------- */
.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}