:root {
  --bg: #f6f5f2; --surface: #ffffff; --ink: #1a213c; --muted: #6a6c7a; --rule: #e7e5e0;
  --navy: #172552; --accent: #109880; --accent-soft: #e0f6f1; --good: #12a086;
  --radius: 14px;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #15182a; --surface: #1e2238; --ink: #eef0f6; --muted: #a2a6ba; --rule: #2d3250; --accent-soft: #163b35; }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: "Pretendard Variable", Pretendard, "Malgun Gothic", sans-serif; line-height: 1.6; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

header { height: 68px; display: flex; align-items: center; }
header .wrap { display: flex; align-items: center; justify-content: space-between; width: 100%; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; text-decoration: none; white-space: nowrap; }
.brand img { width: 36px; height: 36px; }
nav.main { display: flex; gap: 22px; font-size: 15px; font-weight: 600; }
nav.main a { text-decoration: none; color: var(--muted); }
nav.main a:hover, nav.main a.on { color: var(--accent); }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; height: 48px; padding: 0 24px; border-radius: 999px; font-weight: 700; font-size: 16px; text-decoration: none; border: 1px solid transparent; transition: transform .15s ease, background .15s ease; white-space: nowrap; }
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: #0d8470; }
.btn-ghost { background: var(--surface); color: var(--ink); border-color: var(--rule); }
header .btn { height: 40px; padding: 0 18px; font-size: 15px; }

h1.page { font-size: clamp(28px, 3.6vw, 40px); letter-spacing: -0.02em; line-height: 1.2; margin: 36px 0 10px; font-weight: 800; }
h2 { font-size: clamp(24px, 3vw, 32px); letter-spacing: -0.02em; line-height: 1.25; margin: 0 0 12px; font-weight: 800; }
h3 { font-size: 20px; font-weight: 800; margin: 0 0 6px; }
.lead { font-size: 17px; color: var(--muted); margin: 0 0 32px; max-width: 62ch; }
section { padding: 48px 0; }
section + section { border-top: 1px solid var(--rule); }
.card { background: var(--surface); border: 1px solid var(--rule); border-radius: var(--radius); padding: 24px 26px; }
.card p { margin: 0; color: var(--muted); font-size: 16px; }
.card p + p { margin-top: 8px; }
.muted { color: var(--muted); }

.shot { border-radius: var(--radius); overflow: hidden; box-shadow: 0 24px 60px rgba(30, 36, 71, .18); border: 1px solid var(--rule); background: var(--surface); }
.shot img { width: 100%; }

/* guide: one feature per row, image and text alternating is avoided; image always right on desktop */
.feature { display: grid; grid-template-columns: 5fr 6fr; gap: 28px; align-items: center; padding: 28px 0; border-top: 1px solid var(--rule); }
.feature:first-of-type { border-top: 0; }
.feature .text p { color: var(--muted); font-size: 16px; margin: 0 0 8px; }
.feature .text ul { margin: 8px 0 0; padding-left: 18px; color: var(--ink); font-size: 15.5px; }
.feature .text li { margin: 3px 0; }
.feature .when { font-size: 14px; color: var(--accent); font-weight: 700; margin: 0 0 6px; }
.feature .shot { box-shadow: 0 12px 32px rgba(30, 36, 71, .14); }
.toc { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 8px; }
.toc a { font-size: 14px; padding: 6px 12px; border: 1px solid var(--rule); background: var(--surface); border-radius: 999px; text-decoration: none; color: var(--ink); }
.toc a:hover { border-color: var(--accent); color: var(--accent); }

/* faq */
details { background: var(--surface); border: 1px solid var(--rule); border-radius: var(--radius); padding: 0 22px; margin: 0 0 10px; }
summary { cursor: pointer; font-weight: 700; font-size: 17px; padding: 16px 0; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--accent); font-weight: 800; }
details[open] summary::after { content: "\2212"; }
details p { margin: 0 0 16px; color: var(--muted); font-size: 16px; }
details ol, details ul { margin: 0 0 16px; color: var(--muted); font-size: 16px; }

/* notice */
.release { display: grid; grid-template-columns: 150px 1fr; gap: 20px; padding: 22px 0; border-top: 1px solid var(--rule); }
.release:first-of-type { border-top: 0; }
.release .ver { font-weight: 800; font-size: 20px; }
.release .date { color: var(--muted); font-size: 14px; }
.release ul { margin: 0; padding-left: 18px; color: var(--ink); font-size: 16px; }
.release li { margin: 4px 0; }

/* contact */
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.card h3 a { color: var(--accent); text-decoration: none; }
table.plain { border-collapse: collapse; width: 100%; font-size: 15px; }
table.plain th, table.plain td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--rule); vertical-align: top; }
table.plain th { color: var(--muted); font-weight: 600; width: 34%; }

/* privacy */
.legal h3 { margin-top: 26px; }
.legal p, .legal li { color: var(--ink); font-size: 15.5px; }
.legal ul { padding-left: 18px; }

footer { padding: 28px 0 40px; color: var(--muted); font-size: 14px; border-top: 1px solid var(--rule); margin-top: 24px; }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }
footer a { text-decoration: none; }

@media (max-width: 820px) {
  header { height: auto; padding: 12px 0; }
  header .wrap { flex-wrap: wrap; }
  nav.main { order: 3; width: 100%; gap: 16px; overflow-x: auto; }
  .feature, .two { grid-template-columns: 1fr; }
  .release { grid-template-columns: 1fr; gap: 6px; }
  section { padding: 36px 0; }
  h1.page { margin-top: 20px; }
}