/* ===== Design tokens ===== */
:root {
  --bg: #ffffff;
  --bg-alt: #f7f7fb;
  --ink: #1a1a1a;
  --body: #374151;
  --muted: #6b7280;
  --line: #e5e7eb;
  --accent: #6366f1;      /* indigo */
  --accent-ink: #4f46e5;
  --amber: #f59e0b;       /* contact CTA */
  --dark: #17162b;        /* contact + footer */
  --dark-2: #201f3a;
  --radius: 14px;
  --maxw: 1200px;
  --font: 'Inter', 'Noto Sans KR', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--body);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 40px; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 26px; border-radius: 999px; font-weight: 600; font-size: 15px;
  border: 1.5px solid transparent; cursor: pointer; transition: transform .15s ease, box-shadow .15s ease, background .15s ease, color .15s ease;
  white-space: nowrap;
}
.btn:hover { transform: translateY(-1px); }
.btn-sm { padding: 10px 20px; font-size: 14px; }
.btn-dark { background: var(--dark); color: #fff; }
.btn-dark:hover { background: #26244a; box-shadow: 0 8px 20px rgba(23,22,43,.22); }
.btn-outline { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-outline:hover { border-color: var(--accent); color: var(--accent-ink); }
.btn-amber { background: var(--amber); color: #1a1204; }
.btn-amber:hover { background: #fbbf24; box-shadow: 0 10px 24px rgba(245,158,11,.3); }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.85); backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 76px; gap: 24px; }
.brand { font-weight: 700; letter-spacing: .12em; color: var(--ink); font-size: 16px; }
.nav-links { display: flex; gap: 34px; }
.nav-links a { color: var(--body); font-size: 15px; font-weight: 500; }
.nav-links a:hover { color: var(--accent-ink); }
.nav-right { display: flex; align-items: center; gap: 22px; }

/* Language switch */
.lang-switch { display: inline-flex; align-items: center; gap: 8px; }
.lang-btn { background: none; border: 0; padding: 0; cursor: pointer; font: inherit; font-size: 14px; font-weight: 500; color: var(--muted); }
.lang-btn.is-active { color: var(--accent); font-weight: 600; }
.lang-div { color: #d1d5db; }

/* ===== Hero ===== */
.hero { background: #fafafa; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: center; padding: 84px 40px; }
.eyebrow { color: var(--accent); font-weight: 600; font-size: 14px; letter-spacing: .04em; margin: 0 0 18px; }
.hero-title { color: var(--ink); font-size: clamp(30px, 4vw, 46px); line-height: 1.15; font-weight: 700; margin: 0 0 20px; letter-spacing: -.01em; }
.hero-sub { font-size: 18px; color: var(--body); margin: 0 0 30px; max-width: 46ch; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-media img { border-radius: var(--radius); box-shadow: 0 24px 60px rgba(23,22,43,.18); aspect-ratio: 16/10; object-fit: cover; }

/* ===== Section helpers ===== */
.section-alt { background: var(--bg-alt); }
.section-eyebrow { color: var(--accent); font-weight: 700; font-size: 13px; letter-spacing: .16em; margin: 0 0 10px; }
.section-eyebrow.center, .section-title.center { text-align: center; }
.section-title { color: var(--ink); font-size: clamp(26px, 3vw, 34px); font-weight: 700; margin: 0 0 44px; letter-spacing: -.01em; }

/* ===== Featured logos ===== */
.featured { padding: 46px 0; background: #fff; }
.logo-strip { list-style: none; display: flex; flex-wrap: wrap; align-items: center; justify-content: center; gap: 54px; margin: 22px 0 0; padding: 0; }
.logo-strip img { height: 30px; width: auto; object-fit: contain; opacity: .85; transition: opacity .2s ease; }
.logo-strip img:hover { opacity: 1; }

/* ===== Speaking cards ===== */
.speaking { padding: 84px 0; }
.cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 24px; transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease; }
.card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(23,22,43,.1); border-color: transparent; }
.card-emoji { font-size: 30px; display: block; margin-bottom: 16px; }
.card h3 { color: var(--ink); font-size: 17px; font-weight: 600; margin: 0 0 12px; line-height: 1.35; }
.card p { color: var(--muted); font-size: 14.5px; margin: 0; }

/* ===== About ===== */
.about { padding: 84px 0; }
.about-grid { display: grid; grid-template-columns: .8fr 1.2fr; gap: 56px; align-items: start; }
.about-media img { border-radius: var(--radius); box-shadow: 0 20px 50px rgba(23,22,43,.16); aspect-ratio: 16/10; object-fit: cover; }
.about-copy .section-title { margin-bottom: 20px; }
.about-bio { font-size: 16.5px; color: var(--body); margin: 0 0 30px; }
.stats { display: flex; flex-wrap: wrap; gap: 36px; margin-bottom: 26px; }
.stat { display: flex; flex-direction: column; }
.stat-num { color: var(--accent); font-size: 30px; font-weight: 700; line-height: 1.1; }
.stat-label { color: var(--muted); font-size: 13px; margin-top: 4px; max-width: 14ch; }
.chips { display: flex; flex-wrap: wrap; gap: 10px; }
.chip { background: var(--bg-alt); border: 1px solid var(--line); border-radius: 999px; padding: 6px 14px; font-size: 13px; color: var(--body); }

/* ===== Writing ===== */
.writing { padding: 84px 0; }
.articles { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.article { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; display: flex; flex-direction: column; gap: 14px; transition: transform .18s ease, box-shadow .18s ease; }
.article:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(23,22,43,.1); }
.tag { align-self: flex-start; background: #eef2ff; color: var(--accent-ink); font-size: 12px; font-weight: 600; padding: 5px 10px; border-radius: 8px; }
.article h3 { color: var(--ink); font-size: 17px; font-weight: 600; margin: 0; line-height: 1.4; flex: 1; }
.article time { color: var(--muted); font-size: 13px; }

/* ===== Contact ===== */
.contact { background: var(--dark); color: #fff; padding: 84px 0; }
.contact-inner { max-width: 720px; margin: 0 auto; text-align: center; }
.accent-light { color: #a5b4fc; }
.contact-title { font-size: clamp(24px, 3vw, 32px); font-weight: 700; margin: 0 0 18px; color: #fff; line-height: 1.3; }
.contact-sub { color: #c7c6da; font-size: 16.5px; margin: 0 0 30px; }

/* ===== Footer ===== */
.site-footer { background: var(--dark-2); color: #b9b8cc; padding: 22px 0; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.copyright { margin: 0; font-size: 14px; }
.social { display: flex; gap: 28px; }
.social a { font-size: 14px; color: #b9b8cc; }
.social a:hover { color: #fff; }

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .container { padding: 0 22px; }
  .hero-grid { grid-template-columns: 1fr; gap: 36px; padding: 56px 22px; }
  .hero-media { order: -1; }
  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .cards { grid-template-columns: repeat(2, 1fr); }
  .articles { grid-template-columns: 1fr; }
  .nav-links { display: none; }
}
@media (max-width: 520px) {
  .cards { grid-template-columns: 1fr; }
  .stats { gap: 22px; }
  .footer-inner { flex-direction: column; gap: 12px; text-align: center; }
  .nav-right { gap: 14px; }
}