/* SeamStream Landing v2
   seamstream.net 다크 테마 색상 시스템 적용 (2026-05-20)
   - 검정 배경, 흰 텍스트
   - 강철 청색(#2B5672) 브랜드 강조
   - 밝은 파랑(#116DFF) 버튼/인터랙티브
   - 빨강(#E03939) 플로팅 액션
   - 틸(#7CD1D8) 보조 포인트
*/

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

:root {
  --bg: #181818;
  --bg-soft: #1E1E1E;
  --bg-section: #242424;
  --border: rgba(255,255,255,.08);
  --border2: rgba(255,255,255,.04);
  --txt: #FFFFFF;
  --txt2: rgba(255,255,255,.65);
  --txt3: rgba(255,255,255,.42);
  --accent: #7CD1D8;
  --accent-soft: rgba(124,209,216,.12);
  --cta: #116DFF;
  --cta-soft: rgba(17,109,255,.12);
  --red: #E03939;
}

html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--txt);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
}

a { color: inherit; }
/* ── SECTION COMMONS ─────────────────────────────── */
.section-head {
  max-width: 1100px;
  margin: 0 auto 56px;
  padding: 0 40px;
}
.section-tag {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: lowercase;
  color: var(--txt3);
  margin-bottom: 16px;
}
.section-tag::before {
  content: '> ';
  color: var(--accent);
}
.section-title {
  font-size: clamp(28px, 4vw, 48px);
  font-weight: 300;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--txt);
  margin-bottom: 18px;
}
.section-sub {
  font-size: 17px;
  color: var(--txt2);
  max-width: 620px;
  line-height: 1.65;
}
.accent-dot {
  display: inline-block;
  width: 0.18em;
  height: 0.18em;
  border-radius: 50%;
  background: var(--accent);
  margin-left: 0.06em;
  vertical-align: 0.18em;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 28px;
  border-radius: 0;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  text-decoration: none;
  transition: all 0.2s;
  cursor: pointer;
  border: 1px solid var(--txt);
  font-family: inherit;
  white-space: nowrap;
}
.btn-primary { background: var(--txt); color: var(--bg); }
.btn-primary:hover { background: var(--accent); border-color: var(--accent); }
.btn-ghost { background: transparent; color: var(--txt); border-color: var(--border); }
.btn-ghost:hover { border-color: var(--txt); }
/* ── COMPARE ────────────────────────────────────── */
.compare {
  padding: 96px 0;
  border-top: 1px solid var(--border);
  background: var(--bg-soft);
}
.compare-table {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0;
  background: var(--bg);
  border: 1px solid var(--border);
}
.compare-wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 40px;
}
.ct-row {
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr 1.1fr;
  border-bottom: 1px solid var(--border);
}
.ct-row:last-child { border-bottom: 0; }
.ct-cell {
  padding: 18px 20px;
  font-size: 14.5px;
  color: var(--txt2);
  border-left: 1px solid var(--border2);
}
.ct-cell:first-child { border-left: 0; }
.ct-head .ct-cell {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--txt);
  background: var(--bg-soft);
  padding-top: 22px;
  padding-bottom: 22px;
}
.ct-cell-sub {
  font-weight: 400;
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--txt3);
}
.ct-cell-us { background: var(--bg); }
.ct-head .ct-cell-us {
  background: var(--txt);
  color: var(--bg);
  font-size: 18px;
  font-weight: 700;
}
.ct-head .ct-cell-us .ct-cell-sub { color: rgba(24,24,24,.55); }
.ct-cell-us strong {
  color: var(--accent);
  font-weight: 700;
  font-size: 18px;
}
.ct-label {
  font-weight: 500;
  color: var(--txt);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
/* compare-table lives inside padded container on desktop */
.compare > .compare-table { margin-left: 40px; margin-right: 40px; max-width: calc(1100px - 0px); }
@media (min-width: 1181px) {
  .compare > .compare-table { margin-left: auto; margin-right: auto; }
}
/* ── CONTACT ────────────────────────────────────── */
.contact {
  padding: 120px 40px;
  border-top: 1px solid var(--border);
  background: var(--bg);
}
.contact-inner {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}
.contact-title {
  font-size: clamp(28px, 4.6vw, 56px);
  font-weight: 300;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin: 16px 0 20px;
}
.contact-sub {
  font-size: 17px;
  color: var(--txt2);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.65;
}
.contact-actions { margin-top: 40px; display: flex; justify-content: center; }
/* ── FOOTER ─────────────────────────────────────── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  color: var(--txt3);
  letter-spacing: 0.06em;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-brand { flex-shrink: 0; opacity: 0.6; }
.footer-co { flex-shrink: 0; }
.footer-nav { display: flex; gap: 20px; flex-wrap: wrap; }
.footer-nav a {
  color: var(--txt2);
  text-decoration: none;
  transition: color .2s;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 10.5px;
  font-weight: 500;
}
.footer-nav a:hover { color: var(--accent); }
/* ── RESPONSIVE : TABLET (≤960) ─────────────────── */
@media (max-width: 960px) {
  .site-header { padding: 0 28px; gap: 16px; }
  .site-nav { gap: 22px; margin-right: 16px; }
  .hero { flex-direction: column; gap: 40px; padding: 72px 28px 64px; }
  .hero-content { width: 100%; }
  .module-grid { grid-template-columns: repeat(2, 1fr); }
  .module-card {
    border-left: 0;
    border-top: 1px solid var(--border);
    padding: 28px 24px;
  }
  .module-card:nth-child(1), .module-card:nth-child(2) { border-top: 0; }
  .module-card:nth-child(even) { border-left: 1px solid var(--border); }
  .compare > .compare-table { margin-left: 28px; margin-right: 28px; }
  .section-head, .compare-highlight { padding-left: 28px; padding-right: 28px; }
  .engine-cards { padding: 0 28px; }
  .engine-cards { grid-template-columns: 1fr; }
  .engine-card { border-left: 0; border-top: 1px solid var(--border); padding: 28px 0; }
  .engine-card:first-child { border-top: 0; }
  .hero { padding: 72px 28px 64px; }
  .contact { padding: 88px 28px; }
  .compare-highlight { grid-template-columns: 1fr; gap: 22px; }
}

/* ── RESPONSIVE : MOBILE (≤720) ─────────────────── */
@media (max-width: 720px) {
  body { font-size: 14.5px; }

  /* Header */
  .site-header { padding: 0 16px; gap: 10px; height: 56px; }
  .site-nav { display: none; }
  .brand img { height: 24px; }
  .lang-btn { padding: 4px 5px; }
  .beta-badge { font-size: 9px; letter-spacing: 0.16em; }

  /* Hero */
  .hero { flex-direction: column; gap: 32px; padding: 56px 20px 56px; }
  .hero-content { width: 100%; }
  .eyebrow { font-size: 10px; letter-spacing: 0.2em; margin-bottom: 20px; }
  .hero-title { font-size: clamp(32px, 9vw, 46px); line-height: 1.08; }
  .hero-subtitle { font-size: 15px; margin-top: 22px; }
  .hero-stats {
    margin-top: 40px;
    gap: 12px;
    grid-template-columns: 1fr;
    width: 100%;
    max-width: none;
  }
  .stat { padding-left: 14px; border-left-width: 2px; }
  .stat-num { font-size: 26px; }
  .hero-actions { margin-top: 36px; flex-direction: column; align-items: stretch; width: 100%; }
  .hero-actions .btn { width: 100%; padding: 14px 20px; }

  /* Sections */
  .section-head { padding: 0 20px; margin-bottom: 32px; }
  .modules { padding: 64px 0 40px; }
  .module-grid { grid-template-columns: 1fr; padding: 0 20px; gap: 0; }
  .module-card {
    border-left: 0 !important;
    border-top: 1px solid var(--border);
    padding: 26px 0;
  }
  .module-card:first-child { border-top: 0; padding-top: 8px; }
  .module-num { margin-bottom: 18px; }
  .module-name { font-size: 24px; }

  /* Engines */
  .engines { padding: 0 0 64px; }
  .engines .section-head { padding-top: 64px; }
  .engine-cards { grid-template-columns: 1fr; padding: 0 20px; }
  .engine-card { border-left: 0; border-top: 1px solid var(--border); padding: 28px 0; }
  .engine-card:first-child { border-top: 0; }

  /* Compare — table collapses to stacked metric cards */
  .compare { padding: 64px 0; }
  .compare > .compare-table {
    margin: 0 20px;
    border: 0;
    background: transparent;
    display: block;
  }
  .ct-row { display: block; border: 0; margin-bottom: 16px; background: var(--bg); border: 1px solid var(--border); }
  .ct-row:last-child { margin-bottom: 0; }
  .ct-row.ct-head { display: none; }
  .ct-cell {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    border-left: 0;
    border-top: 1px solid var(--border2);
    padding: 12px 16px;
    font-size: 13px;
  }
  .ct-cell::before {
    content: attr(data-label);
    font-size: 10px;
    font-weight: 500;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--txt3);
  }
  .ct-cell.ct-label {
    background: var(--txt);
    color: var(--bg);
    border-top: 0;
    padding: 14px 16px;
    font-size: 11px;
    letter-spacing: 0.16em;
    justify-content: flex-start;
  }
  .ct-cell.ct-label::before { content: ''; display: none; }
  .ct-cell-us {
    background: var(--accent-soft);
    border-top-color: rgba(17,109,255,.2);
  }
  .ct-cell-us::before { color: var(--accent); }
  .compare-highlight {
    padding: 0 20px;
    margin-top: 32px;
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .ch-num { font-size: 38px; }

  /* Contact */
  .contact { padding: 56px 20px 48px; }
  .contact-title { font-size: clamp(26px, 7vw, 36px); }
  .contact-sub { font-size: 15px; }
  .contact-actions .btn { width: auto; min-width: 200px; max-width: 280px; }

  /* Hide widget bubble on mobile — sticky CTA takes over */
  #seam-bubble { display: none !important; }

  /* Footer */
  .site-footer {
    flex-direction: column;
    gap: 14px;
    align-items: flex-start;
    padding: 22px 20px;
  }
  .footer-nav { gap: 18px; }
}

/* ── RESPONSIVE : TINY (≤380) ───────────────────── */
@media (max-width: 380px) {
  .hero-title { font-size: 30px; }
  .stat-num { font-size: 24px; }
  .section-title { font-size: 26px; }
}
/* ── ANIMATIONS ─────────────────────────────────── */

/* Scroll fade-up */
.anim-fade-up {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.65s cubic-bezier(.4,0,.2,1), transform 0.65s cubic-bezier(.4,0,.2,1);
}
.anim-fade-up.is-visible {
  opacity: 1;
  transform: translateY(0);
}
/* Reduced motion override */
@media (prefers-reduced-motion: reduce) {
  .hero::before { animation: none; }
  .anim-fade-up { opacity: 1; transform: none; transition: none; }
  .module-card { transition: background .2s; }
  .module-card:hover { transform: none; box-shadow: none; }
  .ct-head .ct-cell-us.pulse-once { animation: none; }
}
/* ── STICKY CTA ─────────────────────────────────── */
.sticky-cta {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(24,24,24,0.97);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-top: 1px solid var(--border);
  padding: 12px 20px;
  z-index: 45;
  box-shadow: 0 -4px 16px rgba(0,0,0,.06);
  transition: opacity 0.25s ease;
}
.sticky-cta .btn {
  width: 100%;
  min-height: 48px;
  padding: 14px 20px;
}

@media (max-width: 720px) {
  body { padding-bottom: 72px; }
  .mobile-menu-btn { display: flex; }
  .sticky-cta { display: block; }
  .btn { min-height: 44px; }
  .hero-actions .btn { min-height: 48px; }
  .hero-screen { max-height: 260px; object-fit: cover; object-position: top; }
}
/* Chat bubble color override */
#seam-bubble { background-color: #7CD1D8 !important; color: #181818 !important; }

/* ── 3D DEPTH EFFECTS (js/effects.js) ─────────────── */
.hero-screen { will-change: transform; }
.js-tilt {
  transition: background .2s, transform .12s ease-out, box-shadow .25s;
  transform-style: preserve-3d;
}
.js-tilt:hover { box-shadow: 0 10px 28px rgba(0,0,0,.08); }
@media (prefers-reduced-motion: reduce) {
  .hero-screen { will-change: auto; }
}

/* ── Chat widget bubble — 브랜드 틸 덮어쓰기 (위젯 기본=빨강 #d6263d) ── */
#seam-bubble {
  background: var(--accent) !important;
  color: #0C0C0C !important;
  box-shadow: 0 4px 20px rgba(124,209,216,.35) !important;
}
#seam-bubble:hover { box-shadow: 0 6px 28px rgba(124,209,216,.5) !important; }