* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: 'Helvetica Neue', Helvetica, Arial, 'Apple SD Gothic Neo', 'Malgun Gothic', sans-serif;
  background: oklch(0.99 0.002 250);
  color: oklch(0.2 0.01 250);
}
/* flex item의 cross-axis(가로) stretch는 margin:auto가 있으면 무시되어
   내용 크기만큼만 줄어드므로, 기존과 동일하게 가로폭을 100%로 고정한다 */
body > * { width: 100%; }
a { color: oklch(0.55 0.15 250); text-decoration: none; }
a:hover { color: oklch(0.45 0.17 250); }

/* header */
.header {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 24px 64px;
  position: sticky;
  top: 0;
  background: oklch(0.99 0.002 250 / 0.9);
  backdrop-filter: blur(8px);
  z-index: 10;
  border-bottom: 1px solid oklch(0.9 0.01 250);
}
.logo { display: flex; align-items: center; gap: 10px; justify-self: start; }
.logo-mark, .logo-word { height: 36px; width: auto; object-fit: contain; }
.nav { display: flex; gap: 40px; font-size: 15px; font-weight: 500; justify-self: center; }
.nav a { color: oklch(0.3 0.02 255); padding-bottom: 4px; border-bottom: 2px solid transparent; }
.nav a:hover, .nav a.active { color: oklch(0.45 0.14 255); border-bottom-color: oklch(0.45 0.14 255); }
.header-cta { justify-self: end; }

/* buttons */
.btn { display: inline-block; border-radius: 8px; font-weight: 600; text-align: center; cursor: pointer; border: none; font-family: inherit; }
.btn-primary { background: oklch(0.45 0.14 255); color: white; padding: 10px 22px; border-radius: 6px; font-size: 14px; }
.btn-primary:hover { background: oklch(0.4 0.15 255); color: white; }
.btn-lg { padding: 16px 32px; font-size: 16px; border-radius: 8px; }
.btn-outline { border: 1px solid oklch(0.8 0.02 255); color: oklch(0.3 0.02 255); background: transparent; }
.btn-outline:hover { border-color: oklch(0.45 0.14 255); color: oklch(0.45 0.14 255); }
.btn-white { background: white; color: oklch(0.3 0.1 260); padding: 16px 36px; font-size: 16px; }

/* shared page-header banner (About / Manual / QnA) */
.page-hero {
  padding: 96px 64px 72px;
  text-align: center;
  background: linear-gradient(180deg, oklch(0.97 0.015 255) 0%, oklch(0.99 0.002 250) 100%);
  border-bottom: 1px solid oklch(0.92 0.01 250);
}
.page-hero .eyebrow {
  font-size: 13px; font-weight: 700; letter-spacing: 0.08em;
  color: oklch(0.45 0.14 255); margin-bottom: 16px;
}
.page-hero h1 { font-size: 42px; font-weight: 700; margin: 0 0 16px; color: oklch(0.22 0.03 260); }
.page-hero p { font-size: 17px; line-height: 1.7; color: oklch(0.45 0.02 255); margin: 0 auto; max-width: 640px; }

.section-head { text-align: center; max-width: 640px; margin: 0 auto 64px; }
.eyebrow { font-size: 13px; font-weight: 700; letter-spacing: 0.08em; color: oklch(0.45 0.14 255); margin-bottom: 16px; }
.section-head h2 { font-size: 36px; font-weight: 700; margin: 0 0 20px; color: oklch(0.22 0.03 260); }
.section-head p { font-size: 17px; line-height: 1.7; color: oklch(0.45 0.02 255); margin: 0; }

/* footer */
.footer { margin-top: auto; background: oklch(0.22 0.04 260); color: oklch(0.75 0.02 255); padding: 56px 64px 32px; }
.footer-top { display: flex; justify-content: space-between; align-items: center; gap: 48px; max-width: 1200px; margin: 0 auto 32px; flex-wrap: wrap; }
.footer-brand { display: flex; align-items: center; gap: 10px; }
.footer-brand img { height: 26px; }
.footer-brand span { color: white; font-weight: 700; font-size: 16px; }
.footer-links { display: flex; gap: 24px; font-size: 14px; flex-wrap: wrap; }
.footer-links a { color: oklch(0.8 0.02 255); }
.footer-links a:hover { color: white; }
.footer-info { max-width: 1200px; margin: 0 auto; border-top: 1px solid oklch(0.35 0.03 260); padding-top: 24px; font-size: 13px; line-height: 1.9; color: oklch(0.65 0.02 255); }
.footer-copy { max-width: 1200px; margin: 16px auto 0; font-size: 12px; color: oklch(0.55 0.02 255); }

@media (max-width: 860px) {
  .header { grid-template-columns: auto 1fr auto; padding: 16px 20px; }
  .nav { display: none; }
  .page-hero { padding: 64px 24px 48px; }
  .page-hero h1 { font-size: 30px; }
  .footer { padding: 40px 24px 24px; }
}