/* ============================================================
   Minsung Kho — Retro RPG pixel theme
   ============================================================ */

/* Pixel fonts
   - Neo둥근모 (NeoDunggeunmo): Korean + Latin pixel font, used for
     headings / nav / buttons / meta labels.
   - Press Start 2P (loaded per-page from Google Fonts): tiny
     uppercase labels only.
   - Body text stays IBM Plex Sans for readability. */
@font-face {
  font-family: 'NeoDunggeunmo';
  src: url('https://cdn.jsdelivr.net/gh/projectnoonnu/noonfonts_neodgm@1.510/NeoDungGeunMo.woff') format('woff');
  font-weight: normal;
  font-display: swap;
}

:root {
  --bg: #0b0d1a;
  --surface: #12162c;
  --surface-alt: #0e1224;
  --rule: #2c3364;
  --rule-bright: #454e94;
  --text: #eceaf6;
  --text-muted: #9aa0c4;
  --accent: #f2c14e;        /* gold */
  --accent-2: #5de0d2;      /* cyan */
  --accent-3: #ff6ba9;      /* magenta */
  --accent-4: #7ee787;      /* green */
  --accent-soft: rgba(242, 193, 78, 0.12);
  --shadow: rgba(0, 0, 0, 0.55);
  --max-w: 920px;
  --font-pixel: 'NeoDunggeunmo', 'IBM Plex Mono', monospace;
  --font-tiny: 'Press Start 2P', 'NeoDunggeunmo', monospace;
  --font-body: 'IBM Plex Sans', system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background-color: var(--bg);
  /* faint pixel starfield */
  background-image:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='240' height='240'%3E%3Crect x='23' y='41' width='2' height='2' fill='%23ffe066' fill-opacity='0.38'/%3E%3Crect x='161' y='12' width='1' height='1' fill='%23ffd76b' fill-opacity='0.3'/%3E%3Crect x='208' y='87' width='2' height='2' fill='%23f2c14e' fill-opacity='0.22'/%3E%3Crect x='74' y='133' width='1' height='1' fill='%23ffe066' fill-opacity='0.26'/%3E%3Crect x='187' y='203' width='2' height='2' fill='%23ffd76b' fill-opacity='0.34'/%3E%3Crect x='39' y='224' width='1' height='1' fill='%23f2c14e' fill-opacity='0.2'/%3E%3Crect x='118' y='66' width='1' height='1' fill='%23ffe066' fill-opacity='0.18'/%3E%3C/svg%3E");
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: var(--font-pixel);
  font-weight: normal;
  margin: 0;
  color: var(--text);
  letter-spacing: 0.01em;
}

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

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

::selection { background: var(--accent); color: var(--bg); }

/* Pixel art rendering */
.px-art {
  image-rendering: pixelated;
  shape-rendering: crispEdges;
}

.eyebrow {
  font-family: var(--font-pixel);
  font-size: 0.95rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 1rem;
  display: block;
}
.eyebrow::before { content: "▶ "; color: var(--accent); }

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

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 13, 26, 0.92);
  backdrop-filter: blur(6px);
  border-bottom: 3px solid var(--rule);
  box-shadow: 0 3px 0 var(--shadow);
}

.nav {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0.9rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-family: var(--font-pixel);
  font-size: 1.05rem;
  color: var(--text);
  letter-spacing: 0.02em;
}
.nav-brand strong { color: var(--accent); font-weight: normal; }

.nav-links {
  display: flex;
  gap: 1.4rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-family: var(--font-pixel);
  color: var(--text-muted);
  font-size: 0.98rem;
}
.nav-links a:hover { color: var(--accent-2); text-decoration: none; }
.nav-links a.active { color: var(--accent); }
.nav-links a.active::before { content: "▸"; margin-right: 0.3rem; }

.nav-toggle {
  display: none;
  background: var(--surface);
  border: 3px solid var(--rule);
  border-radius: 0;
  color: var(--text);
  font-family: var(--font-pixel);
  padding: 0.3rem 0.6rem;
  font-size: 1rem;
  cursor: pointer;
  box-shadow: 3px 3px 0 var(--shadow);
}
.nav-toggle:active { transform: translate(2px, 2px); box-shadow: 1px 1px 0 var(--shadow); }

/* ---------- Hero (home page only) ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 6rem 0 5rem;
  border-bottom: 3px solid var(--rule);
}

.hero-lattice {
  position: absolute;
  top: 50%;
  right: -2%;
  transform: translateY(-50%);
  width: 440px;
  height: 440px;
  opacity: 0.34;
  pointer-events: none;
}

.hero-inner { position: relative; z-index: 1; max-width: 640px; }

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  line-height: 1.2;
  text-shadow: 4px 4px 0 rgba(0, 0, 0, 0.5);
}

.hero .kr-name {
  display: block;
  font-family: var(--font-pixel);
  font-size: 1.25rem;
  color: var(--accent-2);
  margin-top: 0.5rem;
  font-style: normal;
  text-shadow: 2px 2px 0 rgba(0, 0, 0, 0.5);
}

.hero .tagline {
  margin-top: 1.5rem;
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 560px;
}

.hero-actions {
  margin-top: 2.2rem;
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

/* ---------- Pixel buttons ---------- */
.btn {
  font-family: var(--font-pixel);
  font-size: 0.95rem;
  padding: 0.65rem 1.2rem;
  border-radius: 10px;
  border: 2px solid var(--rule-bright);
  color: var(--text);
  background: var(--surface);
  box-shadow: 3px 3px 0 var(--shadow);
  transition: none;
}
.btn:hover {
  border-color: var(--accent-2);
  color: var(--accent-2);
  text-decoration: none;
  background: var(--surface);
}
.btn:active {
  transform: translate(3px, 3px);
  box-shadow: 1px 1px 0 var(--shadow);
}
.btn-primary {
  border-color: #b8912e;
  color: #1a1405;
  background: var(--accent);
}
.btn-primary:hover { background: #ffd76b; border-color: #c9a04c; color: #1a1405; }

/* ---------- Pixel icon strip (hero) ---------- */
.px-strip {
  margin-top: 3rem;
  display: flex;
  gap: 2.2rem;
  flex-wrap: wrap;
}
.px-strip .px-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
}
.px-strip .px-art { width: 88px; height: 88px; }
.px-strip .px-label {
  font-family: var(--font-tiny);
  font-size: 0.5rem;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  text-transform: uppercase;
}

/* ---------- Page header (subpages) ---------- */
.page-head {
  padding: 4.5rem 0 1rem;
  max-width: 680px;
}
.page-head h1 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  line-height: 1.25;
  text-shadow: 3px 3px 0 rgba(0, 0, 0, 0.5);
}
.page-head-lattice {
  width: 56px;
  height: 56px;
  margin-bottom: 1.2rem;
}

/* ---------- Sections ---------- */
.section { padding: 3rem 0 4.5rem; scroll-margin-top: 4.5rem; }
.section.alt { background: var(--surface-alt); }

.section-head { margin-bottom: 2.2rem; max-width: 600px; }
.section-head h2 { font-size: 1.7rem; }

.prose p { color: var(--text-muted); margin: 0 0 1.1rem; max-width: 640px; }
.prose p:last-child { margin-bottom: 0; }
.prose strong { color: var(--text); font-weight: 500; }

/* ---------- Empty state cards ---------- */
.empty-card {
  border: 3px dashed var(--rule);
  border-radius: 0;
  padding: 2rem 1.8rem;
  color: var(--text-muted);
  font-size: 0.97rem;
  background: rgba(18, 22, 44, 0.5);
}
.empty-card a { color: var(--accent); }
.empty-card::before {
  content: "· · ·";
  display: block;
  font-family: var(--font-pixel);
  color: var(--rule-bright);
  margin-bottom: 0.4rem;
  letter-spacing: 0.3em;
}

/* ---------- Publication / news cards ---------- */
.pub-card, .news-card {
  background: var(--surface);
  border: 2px solid var(--rule);
  border-radius: 12px;
  padding: 1.4rem 1.6rem;
  margin-bottom: 1.1rem;
  box-shadow: 5px 5px 0 var(--shadow);
}
.pub-card:hover, .news-card:hover { border-color: var(--rule-bright); }
.pub-meta, .news-date {
  font-family: var(--font-pixel);
  font-size: 0.82rem;
  color: var(--accent-2);
  letter-spacing: 0.04em;
}
.pub-title {
  font-family: var(--font-pixel);
  font-size: 1.12rem;
  margin: 0.5rem 0 0.35rem;
  font-weight: normal;
  line-height: 1.45;
}
.pub-authors { color: var(--text-muted); font-size: 0.92rem; margin: 0 0 0.5rem; }

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}
.contact-block {
  background: var(--surface);
  border: 3px solid var(--rule);
  padding: 1.5rem 1.7rem;
  box-shadow: 5px 5px 0 var(--shadow);
}
.contact-block h3 {
  font-size: 1rem;
  font-family: var(--font-pixel);
  color: var(--accent);
  letter-spacing: 0.03em;
  margin-bottom: 0.7rem;
}
.contact-block h3::before { content: "◆ "; color: var(--accent-3); }
.contact-block p { color: var(--text-muted); margin: 0.3rem 0; }
.contact-block a { color: var(--text); }
.contact-block a:hover { color: var(--accent-2); }

/* ---------- Figures (smooth vector diagrams) ---------- */
.fig-row {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin-top: 2.5rem;
}
.fig-card {
  background: var(--surface);
  border: 2px solid var(--rule);
  border-radius: 12px;
  padding: 1.4rem 1.4rem 1rem;
  box-shadow: 4px 4px 0 var(--shadow);
  flex: 0 1 280px;
  max-width: 280px;
  text-align: center;
}
.fig-card svg { width: 100%; height: auto; max-width: 210px; }
.fig-caption {
  font-family: var(--font-pixel);
  font-size: 0.88rem;
  color: var(--text-muted);
  margin: 0.8rem 0 0;
}
.fig-caption strong { color: var(--accent); font-weight: normal; }

/* ---------- Footer ---------- */
footer {
  border-top: 3px solid var(--rule);
  padding: 2rem 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-family: var(--font-pixel);
}
/* ---------- Mobile ---------- */
@media (max-width: 720px) {
  .nav-links { display: none; }
  .nav-toggle { display: inline-block; }
  .nav.open .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--surface);
    padding: 1.2rem 1.5rem;
    gap: 1rem;
    border-bottom: 3px solid var(--rule);
  }
  .hero-lattice { width: 260px; height: 260px; opacity: 0.18; right: -12%; }
  .px-strip { gap: 1.4rem; }
  .px-strip .px-art { width: 64px; height: 64px; }
  .contact-grid { grid-template-columns: 1fr; }
}