/*
  research.css
  Styles for the Research section of index.html.
  Scoped to #research so nothing else on the page is affected.
  Link this file in the <head> of index.html with:
    <link rel="stylesheet" href="assets/css/research.css" />
*/

#research,
#test-research {
  --r-coral:   #ff6b6b;
  --r-gold:    #e1e151f0;
  --r-dim:     rgba(255,255,255,0.45);
  --r-border:  rgba(255,255,255,0.10);
  --r-hover:   rgba(255,255,255,0.055);
  --r-disc:    #ff6b6b;
  --r-comet:   #6bcfff;
}

/* ── Intro ── */
.r-intro {
  color: var(--r-dim);
  font-size: 0.96rem;
  margin-bottom: 1.8rem;
  letter-spacing: 0.02rem;
}
.r-intro a { color: var(--r-gold); border-bottom-color: rgba(225,225,81,0.3); }
.r-intro a:hover { color: #fff; border-bottom-color: transparent; }

/* ── Filter bar ── */
.r-filters {
  display: block;
  margin-bottom: 1.4rem;
  padding-bottom: 1.3rem;
  border-bottom: 1px solid var(--r-border);
}
.r-filter-label {
  display: block;
  font-size: 0.66rem;
  letter-spacing: 0.18rem;
  text-transform: uppercase;
  color: var(--r-dim);
  white-space: nowrap;
  margin: 0 0 0.2rem 0;
}
.r-filter-group {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  margin: 0;
}

/* Pill chips */
.r-chip {
  appearance: none;
  background: transparent;
  border: 1px solid var(--r-border);
  border-radius: 2rem;
  color: rgba(255,255,255,0.5);
  cursor: pointer;
  font-family: "Source Sans Pro", sans-serif;
  font-size: 0.74rem;
  font-weight: 300;
  letter-spacing: 0.13rem;
  padding: 0.25rem 0.7rem;
  text-transform: uppercase;
  transition: all 0.18s ease;
  white-space: nowrap;
  line-height: 1.4;
}
.r-chip:hover {
  border-color: rgba(255,255,255,0.3);
  color: #fff;
  background: var(--r-hover);
}
.r-chip.active {
  background: rgba(255,255,255,0.09);
  border-color: rgba(255,255,255,0.5);
  color: #fff;
}
.r-chip.active[data-topic="debris-disc"]   { border-color: var(--r-disc);  color: var(--r-disc); }
.r-chip.active[data-topic="exocomet"]      { border-color: var(--r-comet); color: var(--r-comet); }
.r-chip.active[data-author="first-author"] { border-color: var(--r-gold);  color: var(--r-gold); }
.r-chip.active[data-author="collaborator"] { border-color: rgba(255,255,255,0.45); color: #fff; }

/* Select dropdowns */
.r-select {
  appearance: none;
  background: rgba(255,255,255,0.08) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='9' height='5'%3E%3Cpath d='M0 0l4.5 5L9 0z' fill='rgba(255,255,255,0.9)'/%3E%3C/svg%3E") no-repeat right 0.55rem center;
  background-size: 7px;
  border: 1px solid rgba(255,255,255,0.45);
  border-radius: 2rem;
  color: #fff;
  cursor: pointer;
  font-family: "Source Sans Pro", sans-serif;
  font-size: 0.74rem;
  font-weight: 300;
  letter-spacing: 0.1rem;
  padding: 0.25rem 1.6rem 0.25rem 0.7rem;
  text-transform: uppercase;
  transition: all 0.18s ease;
  display: block;
  margin: 0;
}
.r-select:hover,
.r-select:focus {
  border-color: #fff;
  background-color: rgba(255,255,255,0.15);
  color: #fff;
  outline: none;
  box-shadow: 0 0 0 2px rgba(255,255,255,0.25);
}
.r-select option { background: #1b1f22; color: #fff; }

/* Separator dot between filter groups */
.r-sep {
  width: 0;
  height: 0;
  margin: 0.5rem 0 0;
  display: block;
}

/* ── Results count ── */
.r-count {
  font-size: 0.68rem;
  letter-spacing: 0.16rem;
  text-transform: uppercase;
  color: var(--r-dim);
  margin-bottom: 0.6rem;
}
.r-count strong { color: #fff; font-weight: 600; }

/* ── Paper feed ── */
.r-feed { display: flex; flex-direction: column; }

.r-card {
  display: grid;
  grid-template-columns: minmax(280px, 2fr) minmax(0, 3fr);
  column-gap: 1rem;
  align-items: start;
  border-top: 1px solid var(--r-border);
  padding: 1.3rem 0.5rem 1.3rem 0;
  transition: background 0.18s ease, padding-left 0.18s ease;
}
.r-card:last-of-type { border-bottom: 1px solid var(--r-border); }
.r-card:hover {
  background: var(--r-hover);
  padding-left: 0.65rem;
  border-radius: 4px;
}

@keyframes rIn {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* Card meta row: year + tags */
.r-card-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 0.45rem;
  grid-column: 1 / -1;
}
.r-year-badge {
  font-size: 0.66rem;
  letter-spacing: 0.15rem;
  text-transform: uppercase;
  color: var(--r-dim);
  white-space: nowrap;
}
.r-tags { display: flex; gap: 0.3rem; flex-wrap: wrap; }
.r-tag {
  font-size: 0.62rem;
  letter-spacing: 0.11rem;
  text-transform: uppercase;
  padding: 0.12rem 0.5rem;
  border-radius: 2rem;
  border: 1px solid;
  white-space: nowrap;
  line-height: 1.5;
}
.r-tag-disc   { color: var(--r-disc);  border-color: rgba(255,107,107,0.38); }
.r-tag-comet  { color: var(--r-comet); border-color: rgba(107,207,255,0.38); }
.r-tag-first  { color: var(--r-gold);  border-color: rgba(225,225,81,0.38); }
.r-tag-collab { color: var(--r-dim);   border-color: rgba(255,255,255,0.18); }

/* Title */
.r-title {
  font-size: 1.08rem;
  font-weight: 600;
  color: #fff;
  line-height: 1.45;
  margin: 0 0 0.3rem;
  text-transform: none;
  letter-spacing: 0.01rem;
  grid-column: 1 / -1;
}
.r-title a {
  color: #fff;
  border-bottom: 1px dotted rgba(255,255,255,0.22);
  text-decoration: none;
  transition: color 0.18s, border-bottom-color 0.18s;
}
.r-title a:hover { color: var(--r-gold); border-bottom-color: transparent; }

/* Venue / authors */
.r-venue {
  font-size: 0.82rem;
  color: var(--r-dim);
  font-style: italic;
  margin: 0 0 0.55rem;
  grid-column: 1 / -1;
}
.r-venue strong {
  color: rgba(255,255,255,0.7);
  font-style: normal;
  font-weight: 600;
}

/* Abstract */
.r-abstract {
  font-size: 0.92rem;
  color: rgba(255,255,255,0.65);
  line-height: 1.7;
  margin: 0;
  grid-column: 2;
  grid-row: 4;
}

/* Figure */
.r-figure {
  display: block;
  grid-column: 1;
  grid-row: 4;
  margin: 0;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: 5px;
  border: 1px solid var(--r-border);
  opacity: 0.88;
  transition: opacity 0.2s;
}
.r-figure:hover { opacity: 1; }

/* Empty state */
.r-empty {
  display: none;
  text-align: center;
  color: var(--r-dim);
  font-size: 0.82rem;
  letter-spacing: 0.14rem;
  text-transform: uppercase;
  padding: 2.5rem 0;
}

@media (max-width: 600px) {
  .r-card {
    display: block;
  }
  .r-card:hover { padding-left: 0; background: none; }
  .r-figure {
    margin: 0.9rem 0 0.2rem;
    max-width: 500px;
  }
}
