:root {
  color-scheme: light;
  --color-background: #f5f8fc;
  --color-surface: #ffffff;
  --color-tint: #edf3ff;
  --color-ink: #182a48;
  --color-muted: #58677e;
  --color-accent: #285dde;
  --color-hover: #1c48b7;
  --color-line: #dce5f1;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  --text-small: 0.8125rem;
  --text-body: 0.9375rem;
  --text-title: clamp(2.375rem, 4.6vw, 3.75rem);
  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2rem;
  --space-5: 3rem;
  --space-6: 4rem;
  --content-width: 1080px;
  --radius-card: 24px;
  --radius-control: 10px;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--color-background); color: var(--color-ink); font-family: var(--font-body); -webkit-font-smoothing: antialiased; }
p, h1, h2 { margin: 0; }
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 3px solid var(--color-accent); outline-offset: 5px; }
.page-shell { max-width: var(--content-width); min-height: 100vh; min-height: 100svh; margin: 0 auto; padding: 0 var(--space-4); display: flex; flex-direction: column; }
.site-header { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: var(--space-2); padding: var(--space-4) 0; }
.wordmark { display: flex; align-items: center; gap: 10px; font-size: 1rem; font-weight: 700; letter-spacing: -0.035em; }
.gallery-mark { display: grid; grid-template-columns: repeat(2, 8px); gap: 3px; flex: none; }
.gallery-mark i { height: 8px; border-radius: 2px; background: var(--color-accent); }
.gallery-mark i:last-child { background: var(--color-ink); }
.language-switch { display: flex; gap: 4px; margin-left: auto; }
.language-switch a { min-height: 44px; padding: 0 12px; display: flex; align-items: center; justify-content: center; font-size: var(--text-small); color: var(--color-muted); border-radius: var(--radius-control); }
.language-switch a[aria-current="page"] { background: var(--color-tint); color: var(--color-accent); font-weight: 650; }
.welcome { flex: 1; display: flex; flex-direction: column; justify-content: center; gap: var(--space-5); width: 100%; max-width: 840px; margin: 0 auto; padding: var(--space-4) 0 var(--space-5); }
.introduction { text-align: center; }
.eyebrow { font-size: 0.6875rem; color: var(--color-accent); letter-spacing: 0.14em; font-weight: 700; margin-bottom: var(--space-2); }
h1 { font-size: var(--text-title); font-weight: 750; line-height: 1.25; letter-spacing: -0.065em; word-break: keep-all; }
h1 span { display: block; }
.title-accent { color: var(--color-accent); }
.description { margin: var(--space-2) auto 0; font-size: var(--text-body); color: var(--color-muted); line-height: 1.8; word-break: keep-all; text-wrap: pretty; }
.launch-card { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr); background: var(--color-surface); border: 1px solid var(--color-line); border-radius: var(--radius-card); }
.launch-info { display: flex; flex-direction: column; justify-content: center; align-items: flex-start; padding: var(--space-5) 40px; min-width: 0; }
.section-label { color: var(--color-accent); font-size: 0.6875rem; font-weight: 700; letter-spacing: 0.1em; margin-bottom: var(--space-3); }
h2 { font-size: 1.25rem; font-weight: 700; letter-spacing: -0.035em; line-height: 1.5; word-break: keep-all; }
.launch-description { max-width: 270px; color: var(--color-muted); font-size: var(--text-body); line-height: 1.8; margin-top: var(--space-1); word-break: keep-all; text-wrap: pretty; }
.open-button { display: flex; justify-content: space-between; align-items: center; gap: var(--space-3); background: var(--color-accent); color: var(--color-surface); border-radius: var(--radius-control); width: 100%; min-height: 56px; margin-top: var(--space-3); padding: 14px 20px; font-size: var(--text-body); font-weight: 650; }
.button-arrow { font-size: 1.375rem; line-height: 1; }
.install-note { font-size: 0.75rem; line-height: 1.7; color: var(--color-muted); margin-top: 12px; }
.scan-panel { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: var(--space-2); text-align: center; padding: var(--space-4); border-left: 1px solid var(--color-line); }
.scan-panel h2 { font-size: var(--text-small); font-weight: 600; letter-spacing: 0; }
.qr-code { width: 185px; height: auto; max-width: 100%; display: block; }
.scan-help { max-width: 230px; font-size: 0.75rem; color: var(--color-muted); line-height: 1.75; }
html[lang="en"] h1 { letter-spacing: -0.055em; font-weight: 700; }
@media (hover: hover) {
  .open-button:hover { background: var(--color-hover); }
  .language-switch a:hover { color: var(--color-accent); background: var(--color-tint); }
}
@media (max-width: 760px) {
  .page-shell { max-width: 520px; padding: 0 var(--space-3); }
  .site-header { padding: var(--space-3) 0; gap: var(--space-1); }
  .wordmark { font-size: 0.9375rem; }
  .language-switch a { font-size: 0.75rem; padding: 0 10px; }
  .welcome { padding: var(--space-3) 0 var(--space-2); gap: var(--space-4); }
  h1 { font-size: clamp(2rem, 8.5vw, 2.875rem); }
  .description { max-width: 300px; }
  .launch-card { grid-template-columns: minmax(0, 1fr); }
  .launch-info { padding: var(--space-3); }
  .section-label { margin-bottom: 12px; }
  .launch-description { max-width: none; }
  .scan-panel { border-left: 0; border-top: 1px solid var(--color-line); padding: var(--space-3); }
  .scan-help { max-width: 250px; }
}