/* Bibliobattle Survey Companion Site — Stylesheet */

:root {
  --accent: #1a5276;
  --accent-light: #aed6f1;
  --accent-bg: #eaf2f8;
  --bg: #fafafa;
  --card: #fff;
  --border: #ddd;
  --text: #2c3e50;
  --muted: #7f8c8d;
  --max-width: 980px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Hiragino Kaku Gothic ProN', 'Meiryo', 'Noto Sans JP', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.5rem; }

/* === Header === */
header {
  background: linear-gradient(135deg, #1a5276 0%, #2874a6 100%);
  color: white;
  padding: 2.5rem 0 1.5rem;
}

header h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: .3rem;
}

header h1 .lang-en { color: white; }
header h1 .lang-jp { font-size: 1.4rem; opacity: .9; margin-left: .8rem; font-weight: 400; }

header .subtitle {
  font-size: 1rem;
  opacity: .85;
  margin-bottom: 1.5rem;
}

nav {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  border-top: 1px solid rgba(255,255,255,.2);
  padding-top: 1rem;
}

nav a {
  color: white;
  text-decoration: none;
  font-size: .95rem;
  opacity: .9;
  transition: opacity .2s;
}

nav a:hover { opacity: 1; text-decoration: underline; }

/* === Main === */
main {
  padding: 2.5rem 1.5rem 4rem;
}

section {
  margin-bottom: 3rem;
}

h2 {
  font-size: 1.5rem;
  color: var(--accent);
  border-left: 4px solid var(--accent);
  padding-left: .8rem;
  margin-bottom: 1rem;
}

h3 {
  font-size: 1.15rem;
  margin-bottom: .5rem;
  color: var(--accent);
}

p { margin-bottom: 1rem; }

a { color: #2980b9; }
a:hover { text-decoration: underline; }

ol, ul { padding-left: 1.5rem; margin-bottom: 1rem; }
li { margin-bottom: .3rem; }

/* === Hero section === */
.hero {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 2rem;
  margin-bottom: 2.5rem;
}

.hero h2 { border: none; padding: 0; }

/* === Card grid === */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.card-link {
  display: block;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.2rem 1.5rem;
  text-decoration: none;
  color: var(--text);
  transition: transform .15s, box-shadow .15s, border-color .15s;
}

.card-link:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,.08);
  border-color: var(--accent-light);
  text-decoration: none;
}

.card-link h3 { color: var(--accent); margin-bottom: .5rem; }
.card-link p { font-size: .9rem; color: var(--text); margin: 0; }

/* === Reference list === */
.ref-cat-header {
  background: var(--accent-bg);
  color: var(--accent);
  padding: .5rem 1rem;
  border-radius: 6px;
  margin: 2rem 0 1rem;
  font-size: 1.1rem;
  font-weight: 600;
}

.ref-item {
  background: var(--card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 6px;
  padding: 1rem 1.3rem;
  margin-bottom: .8rem;
}

.ref-id {
  display: inline-block;
  background: var(--accent);
  color: white;
  padding: .15rem .5rem;
  border-radius: 4px;
  font-size: .8rem;
  font-weight: 600;
  margin-right: .5rem;
}

.ref-title-en { font-weight: 600; color: var(--text); display: block; margin-bottom: .2rem; }
.ref-title-jp { color: var(--muted); font-size: .9rem; display: block; margin-bottom: .5rem; }

.ref-meta { font-size: .85rem; color: var(--muted); margin-bottom: .5rem; }
.ref-summary { font-size: .9rem; line-height: 1.6; color: var(--text); }

.ref-tags { margin-top: .5rem; }
.ref-tag {
  display: inline-block;
  background: var(--accent-bg);
  color: var(--accent);
  font-size: .75rem;
  padding: .15rem .5rem;
  border-radius: 3px;
  margin-right: .3rem;
}

.ref-link {
  font-size: .85rem;
  display: inline-block;
  margin-top: .5rem;
}

/* === Stats === */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.stat-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.2rem;
  text-align: center;
}

.stat-num {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.1;
}

.stat-label {
  font-size: .85rem;
  color: var(--muted);
  margin-top: .3rem;
}

/* === Timeline === */
.timeline {
  position: relative;
  padding-left: 2rem;
  margin: 2rem 0;
  border-left: 3px solid var(--accent-light);
}

.tl-item {
  position: relative;
  margin-bottom: 1.5rem;
}

.tl-item::before {
  content: "";
  position: absolute;
  left: -2.4rem;
  top: .5rem;
  width: 12px;
  height: 12px;
  background: var(--accent);
  border-radius: 50%;
  border: 3px solid white;
  box-shadow: 0 0 0 2px var(--accent);
}

.tl-year {
  font-weight: 700;
  color: var(--accent);
  font-size: 1.05rem;
}

.tl-event {
  margin-top: .2rem;
  font-size: .95rem;
}

/* === Tables === */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: .9rem;
}

th, td {
  border: 1px solid var(--border);
  padding: .5rem .8rem;
  text-align: left;
}

th { background: var(--accent-bg); color: var(--accent); font-weight: 600; }
tr:nth-child(even) { background: #f8f9fa; }

/* === Footer === */
footer {
  background: #2c3e50;
  color: #bdc3c7;
  padding: 2rem 0;
  font-size: .85rem;
}

footer a { color: var(--accent-light); }

footer p { margin-bottom: .3rem; }

/* === Responsive === */
@media (max-width: 600px) {
  header h1 { font-size: 1.5rem; }
  header h1 .lang-jp { display: block; margin-left: 0; font-size: 1.1rem; margin-top: .3rem; }
  nav { gap: .8rem; font-size: .85rem; }
}