/* 오토출첵 랜딩. 모서리 규칙: 버튼 12px, 카드·스크린샷 20px, 입력칸 10px. */
:root {
  color-scheme: light;
  --bg: #f6f7f8;
  --surface: #ffffff;
  --tint: #eef0f2;
  --text: #111318;
  --muted: #5d656d;
  --border: #dfe3e7;
  --accent: #111318;
  --accent-hover: #2b3036;
  --accent-soft: #e9ecef;
  --on-accent: #ffffff;
  --ink: #111318;
  --on-ink: #f4f5f6;
  --danger: #ad3038;
  --shadow: 0 1px 2px rgb(20 24 28 / .05), 0 18px 48px -18px rgb(20 24 28 / .2);
  --radius-btn: 12px;
  --radius-card: 20px;
  --radius-input: 10px;
  --wrap: 1180px;
}
/* 다크 모드도 흑백만 쓴다. 강조 면(--ink)은 흰색으로 뒤집는다. */
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0b0c0d;
    --surface: #151719;
    --tint: #101213;
    --text: #f2f3f4;
    --muted: #a3a9b0;
    --border: #2a2e33;
    --accent: #f2f3f4;
    --accent-hover: #d6d9dc;
    --accent-soft: #1f2225;
    --on-accent: #0b0c0d;
    --ink: #f2f3f4;
    --on-ink: #111318;
    --danger: #ff8a80;
    --shadow: 0 1px 2px rgb(0 0 0 / .3), 0 18px 48px -18px rgb(0 0 0 / .6);
  }
  .brand img { filter: invert(1); }
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 64px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.65 "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  word-break: keep-all;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; }
h1, h2, h3 { margin: 0; letter-spacing: -0.02em; line-height: 1.25; }
h2 { font-size: clamp(1.75rem, 1.2rem + 1.8vw, 2.5rem); max-width: 22ch; }
h3 { font-size: 1.2rem; }
p { margin: 0; }
.wrap { width: min(100% - 32px, var(--wrap)); margin-inline: auto; }
.skip { position: absolute; left: 16px; top: -48px; padding: 8px 12px; background: var(--surface); border-radius: var(--radius-btn); z-index: 20; }
.skip:focus { top: 12px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

/* 버튼 */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border: 1px solid transparent; border-radius: var(--radius-btn);
  font: inherit; font-weight: 700; white-space: nowrap; text-decoration: none; cursor: pointer;
  transition: background-color .2s, border-color .2s, transform .15s;
}
.btn:active { transform: translateY(1px) scale(.98); }
.btn i { font-size: 1.25em; }
.btn-sm { padding: 8px 14px; font-size: .9rem; }
.btn-lg { padding: 14px 22px; font-size: 1.02rem; }
.btn-block { width: 100%; }
.btn-primary { background: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-hover); }
.btn-ghost { background: transparent; border-color: var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--muted); }
.btn[disabled] { opacity: .6; cursor: progress; }
.text-link { color: inherit; font-weight: 700; text-underline-offset: 4px; }

/* 상단 메뉴 */
.nav { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 86%, transparent); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); border-bottom: 1px solid transparent; }
.nav-inner { display: flex; align-items: center; gap: 32px; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.1rem; text-decoration: none; }
.nav-links { display: flex; gap: 28px; margin-left: auto; }
.nav-links a { color: var(--muted); text-decoration: none; font-weight: 600; font-size: .95rem; }
.nav-links a:hover { color: var(--text); }

/* 히어로 */
.hero { padding: 48px 0 24px; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: center; min-height: min(720px, calc(100dvh - 64px)); }
.hero h1 { font-size: clamp(2.25rem, 1.4rem + 3vw, 3.6rem); line-height: 1.18; letter-spacing: -0.035em; }
.lead { margin-top: 20px; max-width: 34ch; font-size: 1.15rem; color: var(--muted); }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.hero-shot { margin: 0; justify-self: center; width: min(100%, 400px); transform: rotate(1.5deg); }
.hero-shot img, .cell-shot img, .step img {
  border-radius: var(--radius-card); border: 1px solid var(--border); background: var(--surface); box-shadow: var(--shadow);
}

/* 지원 LMS */
.sites { padding: 24px 0 8px; }
.sites-inner { display: flex; align-items: center; gap: 32px; flex-wrap: wrap; padding-top: 24px; border-top: 1px solid var(--border); }
.sites p { color: var(--muted); font-weight: 600; font-size: .95rem; }
.sites ul { display: flex; gap: 32px; flex-wrap: wrap; margin: 0; padding: 0; list-style: none; }
.sites li { display: flex; align-items: center; gap: 12px; font-weight: 700; }
.sites li img { border-radius: 10px; background: #fff; }

/* 섹션 공통 */
.section { padding: 112px 0; }
.section-tint { background: var(--tint); }
.section h2 { margin-bottom: 48px; }

/* 기능 벤토: 4개 항목, 4칸 */
.bento { display: grid; grid-template-columns: repeat(6, 1fr); gap: 20px; }
.cell { position: relative; overflow: hidden; border-radius: var(--radius-card); padding: 32px; background: var(--surface); border: 1px solid var(--border); }
.cell > i { font-size: 2rem; color: var(--accent); }
.cell h3 { margin-top: 16px; }
.cell p { margin-top: 10px; color: var(--muted); max-width: 46ch; }
.cell-play { grid-column: span 4; background: linear-gradient(135deg, var(--accent-soft), var(--surface) 70%); }
.facts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin: 32px 0 0; }
.facts div { padding-top: 14px; border-top: 1px solid var(--border); }
.facts dt { color: var(--muted); font-size: .9rem; }
.facts dd { margin: 4px 0 0; font-weight: 800; font-size: 1.2rem; }
.cell-private { grid-column: span 2; background: var(--ink); color: var(--on-ink); border-color: transparent; }
.cell-private p { color: color-mix(in srgb, var(--on-ink) 72%, transparent); }
.cell-private > i { color: var(--on-ink); }
.cell-private .text-link { display: inline-block; margin-top: 20px; }
.cell-shot { grid-column: span 3; display: grid; grid-template-rows: auto 1fr; padding-bottom: 0; }
.cell-shot img { width: 78%; margin: 28px auto -40%; transform: translateY(0); transition: transform .5s cubic-bezier(.16, 1, .3, 1); }
.cell-shot:hover img { transform: translateY(-12px); }
.cell-notes { background: linear-gradient(180deg, var(--surface), var(--tint)); }

/* 사용법 */
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px; margin: 0; padding: 0; list-style: none; counter-reset: step; }
.step { counter-increment: step; display: grid; gap: 24px; align-content: start; }
.step:nth-child(2) { margin-top: 48px; }
.step:nth-child(3) { margin-top: 96px; }
.step img { aspect-ratio: 4 / 5; object-fit: cover; object-position: top; }
.step h3::before { content: counter(step); display: inline-grid; place-items: center; width: 28px; height: 28px; margin-right: 10px; border-radius: 50%; background: var(--accent); color: var(--on-accent); font-size: .9rem; vertical-align: 2px; }
.step p { margin-top: 8px; color: var(--muted); }

/* FAQ */
.faq { display: grid; grid-template-columns: 1fr 1.6fr; gap: 48px; align-items: start; }
.faq h2 { position: sticky; top: 96px; }
.faq-list details { border-bottom: 1px solid var(--border); }
.faq-list details:first-child { border-top: 1px solid var(--border); }
.faq-list summary { display: flex; justify-content: space-between; gap: 16px; padding: 22px 0; font-weight: 700; font-size: 1.08rem; cursor: pointer; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; flex: none; color: var(--muted); font-size: 1.4rem; line-height: 1; transition: transform .2s; }
.faq-list details[open] summary::after { transform: rotate(45deg); }
.faq-list details p { padding: 0 0 24px; color: var(--muted); max-width: 62ch; }

/* 문의 */
.contact { display: grid; grid-template-columns: .9fr 1.1fr; gap: 64px; align-items: start; }
.contact-copy p { margin-top: 16px; color: var(--muted); max-width: 40ch; }
.form { display: grid; gap: 22px; padding: 32px; border-radius: var(--radius-card); background: var(--surface); border: 1px solid var(--border); box-shadow: var(--shadow); }
.field { display: grid; gap: 8px; margin: 0; padding: 0; border: 0; min-width: 0; }
.field > label, .field legend { font-weight: 700; padding: 0; }
.field legend { margin-bottom: 8px; }
.field input:not([type="radio"]), .field textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--border); border-radius: var(--radius-input);
  background: var(--bg); color: var(--text); font: inherit; resize: vertical;
}
.field input::placeholder, .field textarea::placeholder { color: var(--muted); opacity: .8; }
.field input:focus, .field textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 25%, transparent); }
.field [aria-invalid="true"] { border-color: var(--danger); }
.help { color: var(--muted); font-size: .88rem; }
.error { color: var(--danger); font-size: .88rem; font-weight: 600; }
.segmented { display: inline-flex; padding: 4px; gap: 4px; border-radius: var(--radius-btn); background: var(--bg); border: 1px solid var(--border); }
.segmented label { position: relative; }
.segmented input { position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; pointer-events: none; }
.segmented span { display: block; padding: 8px 16px; border-radius: 8px; font-weight: 600; color: var(--muted); cursor: pointer; }
.segmented input:checked + span { background: var(--surface); color: var(--text); box-shadow: 0 1px 3px rgb(0 0 0 / .12); }
.segmented input:focus-visible + span { outline: 3px solid var(--accent); outline-offset: 1px; }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.form-status { padding: 12px 14px; border-radius: var(--radius-input); font-weight: 600; }
.form-status.ok { background: var(--accent-soft); color: var(--text); }
.form-status.fail { background: color-mix(in srgb, var(--danger) 12%, transparent); color: var(--danger); }

/* 마무리 */
.closing { padding: 96px 0; }
.closing-inner { display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap; padding: 48px; border-radius: var(--radius-card); background: var(--ink); color: var(--on-ink); }
.closing h2 { max-width: 20ch; }
.closing .btn-primary { background: var(--on-ink); color: var(--ink); }
.closing .btn-primary:hover { background: color-mix(in srgb, var(--on-ink) 85%, var(--ink)); }

/* 하단 */
.footer { padding: 40px 0 56px; border-top: 1px solid var(--border); color: var(--muted); font-size: .9rem; }
.footer-inner { display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
.footer .brand { color: var(--text); font-size: 1rem; }
.footer nav { display: flex; gap: 20px; }
.footer nav a { text-decoration: none; }
.footer nav a:hover { color: var(--text); }
.footer p { margin-left: auto; }

/* 휴대폰·태블릿: 확장을 설치할 수 없으니 스토어 버튼 대신 링크 복사를 보여 준다. */
.mobile-only { display: none; }
@media (hover: none) and (pointer: coarse) {
  .btn[data-store] { display: none; }
  .mobile-only { display: inline-flex; }
  .mobile-note { display: grid; gap: 16px; margin-top: 32px; }
  .mobile-note p { color: var(--muted); }
}

/* 섹션 단위 스크롤: 데스크톱에서 휠을 굴리면 다음 섹션 머리에 멈춘다.
   화면보다 긴 섹션은 브라우저가 안쪽을 자유롭게 스크롤하게 둔다. 터치·모션 줄이기에서는 끈다. */
@media (min-width: 1024px) and (min-height: 640px) and (hover: hover) and (prefers-reduced-motion: no-preference) {
  html { scroll-snap-type: y mandatory; }
  .hero, .section, .closing { scroll-snap-align: start; }
  .section { min-height: calc(100dvh - 64px); display: flex; align-items: center; }
}

/* 등장 모션: 읽는 순서대로 내용을 드러낸다. 모션 줄이기 설정이면 바로 보인다. */
@media (prefers-reduced-motion: no-preference) {
  .js .reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s cubic-bezier(.16, 1, .3, 1), transform .7s cubic-bezier(.16, 1, .3, 1); transition-delay: var(--delay, 0s); }
  .js .reveal.in { opacity: 1; transform: none; }
  .js .hero-shot.reveal.in { transform: rotate(1.5deg); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .cell-shot img { transition: none; }
}

/* 태블릿 */
@media (max-width: 1023px) {
  .nav-links { display: none; }
  .nav-inner .btn { margin-left: auto; }
  .bento { grid-template-columns: 1fr 1fr; }
  .cell-play, .cell-private { grid-column: span 2; }
  .cell-shot { grid-column: span 1; }
  .faq, .contact { grid-template-columns: 1fr; gap: 32px; }
  .faq h2 { position: static; }
}
/* 모바일: 한 줄로 쌓는다 */
@media (max-width: 767px) {
  .hero { padding-top: 32px; }
  .hero-grid { grid-template-columns: 1fr; gap: 40px; min-height: 0; }
  .hero-shot { width: min(86%, 340px); }
  .hero-cta .btn { flex: 1 1 auto; }
  .section { padding: 72px 0; }
  .section h2 { margin-bottom: 32px; }
  .bento { grid-template-columns: 1fr; }
  .cell-play, .cell-private, .cell-shot { grid-column: auto; }
  .cell { padding: 24px; }
  .facts { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; gap: 48px; }
  .step:nth-child(n) { margin-top: 0; }
  .step img { width: min(100%, 320px); }
  .form { padding: 24px; }
  .closing { padding: 64px 0; }
  .closing-inner { padding: 32px 24px; }
  .footer p { margin-left: 0; }
}