:root {
  --bg: #F4F7F8;
  --bg-panel: #EAF0F1;
  --bg-ink: #101A22;
  --bg-ink-alt: #172530;
  --ink: #16222B;
  --ink-muted: #57676F;
  --line: #C9D6D9;
  --line-strong: #9FB2B6;
  --accent: #0E7C86;
  --accent-dark: #0A5B63;
  --accent-soft: #DCEEEF;
  --warn: #E2A33D;
  --white: #FFFFFF;
  --font-display: 'Noto Serif KR', serif;
  --font-body: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Malgun Gothic', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Consolas', monospace;
  --container-width: 1200px;
}

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

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.65;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font: inherit; cursor: pointer; border: none; background: none; }

.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---- Section headings ---- */
.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 14px;
}
.section-eyebrow::before {
  content: "";
  width: 18px;
  height: 2px;
  background: var(--accent);
}

.section-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 3.6vw, 38px);
  color: var(--ink);
  margin-bottom: 16px;
  line-height: 1.35;
  letter-spacing: -0.01em;
}

.section-desc {
  font-size: 16px;
  color: var(--ink-muted);
  max-width: 620px;
}

.section-head {
  margin-bottom: 48px;
}
.section-head.center { text-align: center; }
.section-head.center .section-desc { margin: 0 auto; }
.section-head.center .section-eyebrow { justify-content: center; }
.section-head.center .section-eyebrow::before { display: none; }

section { padding: 88px 0; }

@media (max-width: 768px) {
  .container { padding: 0 18px; }
  section { padding: 64px 0; }
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 14px 26px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 15px;
  background: var(--accent);
  color: #fff;
  transition: background 0.2s ease, transform 0.2s ease;
}
.btn:hover { background: var(--accent-dark); transform: translateY(-2px); }

.btn-outline {
  background: transparent;
  border: 1.5px solid var(--line-strong);
  color: var(--ink);
}
.btn-outline:hover { background: var(--ink); border-color: var(--ink); color: #fff; }

.btn-ghost-light {
  background: rgba(255,255,255,0.08);
  border: 1.5px solid rgba(255,255,255,0.28);
  color: #fff;
}
.btn-ghost-light:hover { background: rgba(255,255,255,0.16); }

.btn-kakao {
  background: #FEE500;
  color: #3A1D1D;
}
.btn-kakao:hover { background: #FDD800; color: #3A1D1D; }
.btn-kakao svg { flex-shrink: 0; }

/* ---- Spec / tag chips (glass-sample swatch tag motif) ---- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 13.5px;
  font-weight: 700;
}

.spec-tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.02em;
}

/* ---- Window-mullion divider: the site's signature motif ----
   A thin crossbar line between major sections, echoing a window's
   muntin bar where two glass panes meet. */
.pane-divider {
  position: relative;
  height: 1px;
  background: var(--line);
}
.pane-divider::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 1px;
  height: 17px;
  background: var(--line-strong);
  transform: translate(-50%, -50%);
}

/* ---- Lightbox ---- */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px;
  background: rgba(9, 14, 18, 0.94);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}
.lightbox.is-open { opacity: 1; visibility: visible; }
.lightbox-img {
  max-width: 100%;
  max-height: 100%;
  border-radius: 4px;
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.5);
}
.lightbox-close {
  position: absolute;
  top: 24px;
  right: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  font-size: 26px;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s ease;
}
.lightbox-close:hover { background: rgba(255, 255, 255, 0.24); }

@media (max-width: 640px) {
  .lightbox { padding: 16px; }
  .lightbox-close { top: 12px; right: 12px; }
}