/* ==========================================================================
   KOREA EM — SUNCOM · SAFET 2026
   Design tokens
   ========================================================================== */
:root {
  --navy-950: #0a1a2e;
  --navy-900: #0d2340;
  --navy-800: #123057;
  --blue-600: #1a5fb4;
  --blue-500: #2f7fe0;
  --orange-500: #f5a623;
  --orange-600: #e08e0b;
  --ink-900: #111827;
  --ink-700: #374151;
  --ink-500: #6b7280;
  --paper-0: #ffffff;
  --paper-50: #f7f9fc;
  --paper-100: #eef2f7;
  --line: #e2e8f0;

  --radius: 14px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 3px rgba(16, 24, 40, 0.08);
  --shadow-md: 0 8px 24px rgba(16, 24, 40, 0.10);
  --container: 1120px;

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans KR", Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink-900);
  background: var(--paper-0);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4 { margin: 0; line-height: 1.25; }
p { margin: 0; }

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

/* ==========================================================================
   Header / Nav
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 26, 46, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
}
.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--blue-500), var(--orange-500));
  color: #fff;
  font-size: 14px;
}
.brand-text strong { color: var(--orange-500); }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 20px;
  cursor: pointer;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}
.main-nav a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 14.5px;
  font-weight: 500;
  transition: color 0.15s ease;
}
.main-nav a:hover { color: #fff; }
.main-nav a.active { color: #fff; position: relative; }
.main-nav a.active::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -14px;
  height: 2px;
  background: var(--orange-500);
}
.nav-cta {
  padding: 8px 16px;
  border-radius: 999px;
  background: var(--orange-500);
  color: var(--navy-950) !important;
  font-weight: 700 !important;
}
.nav-cta:hover { background: var(--orange-600); }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative;
  min-height: 78vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  color: #fff;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(100deg, rgba(9,20,38,0.92) 30%, rgba(9,20,38,0.55) 75%);
}
.hero-content {
  position: relative;
  max-width: var(--container);
  margin: 0 auto;
  padding: 120px 24px 80px;
  width: 100%;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13.5px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--orange-500);
  text-transform: uppercase;
  margin-bottom: 18px;
}
.hero h1 {
  font-size: clamp(32px, 5.5vw, 56px);
  font-weight: 800;
  max-width: 14ch;
  margin-bottom: 20px;
}
.hero-sub {
  font-size: clamp(15px, 2vw, 18px);
  color: rgba(255, 255, 255, 0.85);
  max-width: 46ch;
  margin-bottom: 34px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 15px;
  transition: transform 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--orange-500); color: var(--navy-950); }
.btn-primary:hover { background: var(--orange-600); }
.btn-ghost {
  border: 1.5px solid rgba(255, 255, 255, 0.5);
  color: #fff;
}
.btn-ghost:hover { border-color: #fff; }

/* ==========================================================================
   Sections
   ========================================================================== */
.section { padding: 88px 0; }
.section-alt { background: var(--paper-50); }
.section-dark {
  background: linear-gradient(160deg, var(--navy-950), var(--navy-900));
  color: #fff;
}

.kicker {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--blue-600);
  margin-bottom: 12px;
}
.kicker-light { color: var(--orange-500); }
.kicker-emr { color: var(--blue-600); }
.kicker-rem { color: var(--orange-600); }
.kicker-emp { color: var(--blue-600); }

.section h2 {
  font-size: clamp(26px, 3.6vw, 38px);
  font-weight: 800;
  max-width: 22ch;
  margin-bottom: 20px;
}
.section h2.light { color: #fff; }

.lede {
  font-size: 16.5px;
  color: var(--ink-700);
  max-width: 68ch;
  margin-bottom: 40px;
}
.section-dark .lede { color: rgba(255,255,255,0.75); }

.figure { margin: 40px 0 0; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-md); }
.figure img { width: 100%; }

/* ==========================================================================
   Timeline
   ========================================================================== */
.timeline {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 12px;
}
.timeline-item {
  border-top: 3px solid var(--blue-600);
  padding-top: 16px;
}
.timeline-item-current { border-top-color: var(--orange-500); }
.timeline-year {
  display: block;
  font-weight: 800;
  font-size: 17px;
  color: var(--blue-600);
  margin-bottom: 6px;
}
.timeline-item-current .timeline-year { color: var(--orange-600); }
.timeline-title { font-weight: 700; margin-bottom: 4px; }
.timeline-desc { font-size: 14px; color: var(--ink-500); }

.timeline-tag {
  margin-top: 36px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  font-weight: 700;
  font-size: 16px;
  text-align: center;
}

/* ==========================================================================
   Solution overview cards
   ========================================================================== */
.solution-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
  margin-bottom: 8px;
}
.solution-card {
  display: block;
  background: var(--paper-0);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.solution-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.solution-index {
  display: inline-block;
  font-size: 13px;
  font-weight: 800;
  color: var(--ink-500);
  margin-bottom: 10px;
}
.solution-card h3 {
  font-size: 26px;
  font-weight: 800;
  color: var(--navy-900);
}
.solution-name { font-weight: 600; color: var(--blue-600); margin: 4px 0 12px; font-size: 14.5px; }
.solution-desc { color: var(--ink-700); font-size: 14.5px; margin-bottom: 18px; }
.solution-link { font-size: 14px; font-weight: 700; color: var(--orange-600); display: inline-flex; align-items: center; gap: 6px; }

/* ==========================================================================
   Solution detail sections
   ========================================================================== */
.solution-detail { scroll-margin-top: 80px; }
.detail-media {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  margin-bottom: 44px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 44px;
}
.feature-card {
  background: var(--paper-0);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 22px;
}
.section-alt .feature-card { background: var(--paper-0); }
.feature-icon { font-size: 20px; color: var(--blue-600); margin-bottom: 12px; }
.feature-card h4 { font-size: 15.5px; margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--ink-700); }

.feature-columns {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  margin-bottom: 40px;
}
.feature-col h4 {
  font-size: 16px;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--navy-900);
}
.feature-col ul li {
  padding: 9px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14.5px;
  color: var(--ink-700);
  padding-left: 18px;
  position: relative;
}
.feature-col ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 17px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--orange-500);
}
.feature-col ul li:last-child { border-bottom: none; }

.video-block {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  background: #000;
}
.video-block video { width: 100%; display: block; }

/* ==========================================================================
   Why SUNCOM
   ========================================================================== */
.why-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.why-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius);
  padding: 26px;
}
.why-card .feature-icon { color: var(--orange-500); }
.why-card h4 { color: #fff; font-size: 17px; margin-bottom: 10px; }
.why-card p { color: rgba(255, 255, 255, 0.72); font-size: 14.5px; }

/* ==========================================================================
   Banner
   ========================================================================== */
.banner-section {
  background: linear-gradient(120deg, var(--blue-600), var(--navy-900));
  padding: 64px 24px;
  text-align: center;
  color: #fff;
}
.banner-content h3 { font-size: clamp(22px, 3.4vw, 30px); margin-bottom: 10px; }
.banner-content p { font-size: 16px; color: rgba(255, 255, 255, 0.85); }

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  background: var(--navy-950);
  color: rgba(255, 255, 255, 0.75);
  padding: 48px 24px;
  text-align: center;
  scroll-margin-top: 80px;
}
.footer-content p { margin: 6px 0; font-size: 14.5px; }
.footer-brand { font-weight: 800; color: #fff; font-size: 16px; }
.footer-content a { color: var(--orange-500); }
.footer-content a:hover { text-decoration: underline; }
.footer-note { color: rgba(255,255,255,0.5); font-size: 13px; margin-top: 14px !important; }
.footer-copy { color: rgba(255,255,255,0.4); font-size: 12.5px; margin-top: 4px !important; }

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 880px) {
  .timeline { grid-template-columns: repeat(2, 1fr); }
  .solution-grid { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-columns { grid-template-columns: 1fr; }
  .why-grid { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .nav-toggle { display: block; }
  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--navy-950);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
  }
  .main-nav.open { max-height: 320px; }
  .main-nav a {
    width: 100%;
    padding: 14px 24px;
    border-top: 1px solid rgba(255,255,255,0.08);
  }
  .nav-cta { border-radius: 0; text-align: center; }
  .hero-content { padding: 100px 20px 60px; }
  .section { padding: 60px 0; }
  .timeline { grid-template-columns: 1fr 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
}