:root {
  --navy: #071a31;
  --blue: #185bd8;
  --cyan: #11a9c4;
  --ink: #142237;
  --muted: #5b6c80;
  --line: #dce5ee;
  --soft: #f3f7fb;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: "Pretendard Variable", "Noto Sans KR", "Malgun Gothic", sans-serif;
  line-height: 1.7;
  background: #fff;
}
body.video-modal-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }
.container { width: min(calc(100% - 40px), var(--max)); margin: auto; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav { height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: flex; align-items: center; gap: 12px; font-weight: 900; font-size: 1.35rem; }
.brand-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(135deg, var(--blue), var(--cyan));
  border-radius: 9px;
  font-size: .8rem;
}
.nav-links { display: flex; align-items: center; gap: 28px; font-size: .94rem; font-weight: 700; color: #425269; }
.nav-links a:hover { color: var(--blue); }
.nav-actions { display: flex; align-items: center; gap: 9px; }
.lang-switch, .video-button, .nav-cta {
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-weight: 800;
}
.lang-switch { min-width: 42px; border: 1px solid var(--line); color: #425269; }
.video-button { padding: 0 14px; border: 1px solid var(--line); background: #fff; color: #425269; cursor: pointer; }
.video-button:hover, .lang-switch:hover { border-color: var(--blue); color: var(--blue); }
.nav-cta { padding: 0 17px; background: var(--blue); color: #fff !important; }

.hero { position: relative; overflow: hidden; background: var(--navy); color: #fff; }
.hero::after {
  content: "";
  position: absolute;
  width: 560px;
  height: 560px;
  right: -130px;
  top: -220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(17,169,196,.32), transparent 68%);
}
.hero-grid { min-height: 650px; display: grid; grid-template-columns: 1.08fr .92fr; align-items: center; gap: 70px; position: relative; z-index: 1; }
.eyebrow { color: #54d3e6; font-weight: 800; letter-spacing: .12em; font-size: .82rem; }
.hero h1 { font-size: clamp(2.65rem, 5vw, 5rem); line-height: 1.08; letter-spacing: -.055em; margin: 20px 0 24px; }
.hero-line { display: block; white-space: nowrap; }
.hero h1 .hero-line-accent { color: #6ce0ef; }
.hero-copy { max-width: 680px; font-size: 1.12rem; color: #c7d5e7; margin: 0; }
.actions { display: flex; gap: 12px; margin-top: 34px; flex-wrap: wrap; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 50px; padding: 0 22px; border-radius: 8px; font-weight: 800; }
.btn-primary { background: var(--blue); }
.btn-secondary { border: 1px solid #71849e; background: transparent; cursor: pointer; }
.hero-visual { padding: 34px; background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.12); }
.visual-title { font-size: .84rem; color: #8da3bd; font-weight: 800; letter-spacing: .08em; }
.ai-flow { margin-top: 22px; display: grid; gap: 11px; }
.ai-row { display: grid; grid-template-columns: 92px 1fr; align-items: center; gap: 18px; padding: 14px 16px; background: rgba(255,255,255,.075); border-left: 3px solid #4fd4e7; }
.ai-row strong { font-size: .78rem; color: #6ce0ef; }
.ai-row span { font-weight: 700; }

section { padding: 104px 0; }
.section-head { display: grid; grid-template-columns: .65fr 1.35fr; gap: 60px; margin-bottom: 54px; }
.kicker { display: block; color: var(--blue); font-weight: 900; font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; }
.section-head h2 { font-size: clamp(2rem, 3.2vw, 3.25rem); line-height: 1.2; letter-spacing: -.045em; margin: 10px 0 0; }
.section-head p { margin: 28px 0 0; color: var(--muted); font-size: 1.05rem; }
.problem, .features, .faq { background: var(--soft); }
.problem-grid, .feature-grid { display: grid; grid-template-columns: repeat(3,1fr); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.problem-item, .feature { padding: 34px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: #fff; }
.num { display: block; color: var(--blue); font-weight: 900; font-size: .8rem; }
.problem-item h3, .feature h3 { margin: 28px 0 10px; font-size: 1.25rem; }
.problem-item p, .feature p { margin: 0; color: var(--muted); }
.process-line { display: grid; grid-template-columns: repeat(5,1fr); border: 1px solid var(--line); }
.step { min-height: 205px; padding: 28px 24px; border-right: 1px solid var(--line); }
.step:last-child { border: 0; background: var(--blue); color: #fff; }
.step small { color: var(--blue); font-weight: 900; }
.step:last-child small { color: #bfe9ff; }
.step h3 { margin: 40px 0 9px; font-size: 1.08rem; }
.step p { margin: 0; font-size: .9rem; color: var(--muted); }
.step:last-child p { color: #dceaff; }
.feature-grid { grid-template-columns: repeat(2,1fr); }
.feature { min-height: 210px; }
.feature-icon { width: 44px; height: 44px; display: grid; place-items: center; background: #e8f1ff; color: var(--blue); font-weight: 900; border-radius: 8px; }
.architecture { background: var(--navy); color: #fff; }
.architecture .section-head p { color: #aebed1; }
.architecture .kicker { color: #54d3e6; }
.layers { display: grid; gap: 10px; }
.layer { display: grid; grid-template-columns: 220px 1fr; align-items: center; gap: 30px; padding: 22px 26px; background: rgba(255,255,255,.06); border-left: 3px solid var(--cyan); }
.layer strong { color: #65d7e7; }
.benefit-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 26px; }
.benefit { padding-top: 20px; border-top: 4px solid var(--blue); }
.benefit h3 { font-size: 1.18rem; margin: 14px 0 9px; }
.benefit p { margin: 0; color: var(--muted); font-size: .95rem; }
.faq-list { border-top: 1px solid var(--line); }
details { border-bottom: 1px solid var(--line); background: #fff; }
summary { cursor: pointer; list-style: none; padding: 23px 24px; font-weight: 800; font-size: 1.05rem; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; float: right; color: var(--blue); font-size: 1.4rem; }
details[open] summary::after { content: "−"; }
details p { padding: 0 24px 24px; margin: 0; color: var(--muted); }
.contact { padding: 86px 0; background: linear-gradient(120deg,#103d70,#0b7d99); color: #fff; }
.contact-grid { display: grid; grid-template-columns: 1.25fr .75fr; gap: 70px; align-items: center; }
.contact h2 { margin: 0 0 15px; font-size: clamp(2rem,3vw,3rem); letter-spacing: -.04em; line-height: 1.25; }
.contact p { color: #d8edfa; margin: 0; }
.contact-card { padding: 27px; border: 1px solid rgba(255,255,255,.25); background: rgba(255,255,255,.09); }
.contact-card strong { display: block; font-size: 1.15rem; margin-bottom: 10px; }
.contact-card a { display: block; margin-top: 4px; }
footer { padding: 27px 0; background: #061426; color: #8fa2ba; font-size: .86rem; }
.footer-row { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; }

.video-modal { position: fixed; inset: 0; z-index: 100; display: none; place-items: center; padding: 24px; }
.video-modal.open { display: grid; }
.video-modal-backdrop { position: absolute; inset: 0; background: rgba(3,11,24,.82); backdrop-filter: blur(5px); }
.video-dialog { position: relative; width: min(100%, 1040px); background: #071a31; border: 1px solid rgba(255,255,255,.16); border-radius: 14px; box-shadow: 0 24px 80px rgba(0,0,0,.45); overflow: hidden; }
.video-modal-header { min-height: 62px; display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 12px 16px 12px 22px; color: #fff; }
.video-modal-header h2 { margin: 0; font-size: 1rem; }
.video-modal-actions { display: flex; align-items: center; gap: 16px; }
.video-modal-actions a { color: #8ee7f3; font-size: .86rem; font-weight: 700; }
.video-close { width: 38px; height: 38px; border: 0; border-radius: 50%; background: rgba(255,255,255,.1); color: #fff; font-size: 1.65rem; line-height: 1; cursor: pointer; }
.video-close:hover { background: rgba(255,255,255,.18); }
.video-frame { position: relative; aspect-ratio: 16/9; background: #000; }
.video-frame iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }

@media (max-width: 1040px) {
  .nav-links { gap: 18px; }
  .nav-links a:not(.nav-cta) { display: none; }
}
@media (max-width: 900px) {
  .hero-grid, .section-head, .contact-grid { grid-template-columns: 1fr; }
  .hero-grid { padding: 82px 0; min-height: auto; gap: 46px; }
  .problem-grid, .feature-grid, .process-line { grid-template-columns: 1fr; }
  .step { min-height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .step h3 { margin: 18px 0 7px; }
  .benefit-grid { grid-template-columns: 1fr 1fr; }
  .section-head { gap: 8px; }
}
@media (max-width: 620px) {
  .container { width: min(calc(100% - 30px),var(--max)); }
  .nav { height: 64px; }
  .nav-actions { gap: 6px; }
  .video-button { width: 40px; padding: 0; font-size: 0; }
  .video-button span { font-size: .9rem; }
  .nav-cta { padding: 0 12px; }
  .hero h1 { font-size: 2.55rem; }
  .hero-line { white-space: normal; }
  .hero-copy { font-size: 1rem; }
  .hero-visual { padding: 20px; }
  .ai-row { grid-template-columns: 76px 1fr; padding: 12px; }
  .actions .btn { width: 100%; }
  section { padding: 76px 0; }
  .section-head { margin-bottom: 34px; }
  .section-head h2 { font-size: 2rem; }
  .problem-item, .feature { padding: 26px; }
  .benefit-grid { grid-template-columns: 1fr; }
  .layer { grid-template-columns: 1fr; gap: 6px; padding: 19px; }
  .contact { padding: 65px 0; }
  .video-modal { padding: 10px; }
  .video-modal-header { align-items: flex-start; }
  .video-modal-actions a { display: none; }
}