:root {
  --brand: #55a859;
  --brand-dark: #153e2b;
  --brand-soft: #eaf6e8;
  --ink: #18231d;
  --muted: #607066;
  --line: #dce6de;
  --paper: #ffffff;
  --bg: #f4f7f4;
  --accent: #f6b800;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 96px; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", system-ui, -apple-system, sans-serif; font-size: 16px; line-height: 1.7; }
img { display: block; max-width: 100%; }
a { color: inherit; }

.skip-link { position: fixed; left: 12px; top: -60px; z-index: 20; padding: 10px 14px; border-radius: 8px; background: #fff; color: var(--brand-dark); font-weight: 800; }
.skip-link:focus { top: 12px; }

.guide-header { min-height: 66px; display: flex; align-items: center; justify-content: space-between; gap: 14px; padding: 10px max(16px, env(safe-area-inset-left)); background: rgba(255,255,255,.96); border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 9px; text-decoration: none; }
.brand img { width: 38px; height: 38px; object-fit: contain; }
.brand span { display: grid; line-height: 1.12; }
.brand strong { color: var(--brand-dark); font-size: 16px; letter-spacing: -.02em; }
.brand small { margin-top: 4px; color: var(--muted); font-size: 11px; font-weight: 700; letter-spacing: .06em; }
.back-link { flex: 0 0 auto; padding: 8px 0; color: var(--brand-dark); font-size: 13px; font-weight: 800; text-decoration-thickness: 1px; text-underline-offset: 4px; }

.intro { background: var(--brand-dark); color: #fff; }
.intro-inner { width: min(100% - 32px, 920px); margin: 0 auto; padding: 42px 0 36px; }
.eyebrow { margin: 0 0 10px; color: #9fd5a1; font-size: 12px; font-weight: 900; letter-spacing: .14em; }
.intro h1 { margin: 0; font-size: clamp(2.25rem, 11vw, 4.8rem); line-height: 1.08; letter-spacing: -.055em; }
.intro h1 span { display: block; color: #a9dea9; font-size: .72em; letter-spacing: -.06em; white-space: nowrap; }
.lead { max-width: 720px; margin: 18px 0 0; color: #e2ece4; font-size: 17px; line-height: 1.75; }
.reward-card { display: flex; gap: 13px; margin-top: 24px; padding: 16px; border: 1px solid rgba(255,255,255,.22); border-radius: 14px; background: rgba(255,255,255,.09); }
.reward-icon { width: 34px; height: 34px; flex: 0 0 34px; display: grid; place-items: center; border-radius: 50%; background: var(--brand); color: #fff; font-size: 20px; font-weight: 900; }
.reward-card b { font-size: 16px; }
.reward-card p { margin: 2px 0 0; color: #e8f1e9; line-height: 1.55; }
.screen-note { margin: 16px 0 0; color: #bfcfc3; font-size: 13px; }

.step-nav { position: sticky; top: 0; z-index: 10; overflow-x: auto; border-bottom: 1px solid var(--line); background: rgba(255,255,255,.96); box-shadow: 0 6px 18px rgba(21,62,43,.07); backdrop-filter: blur(12px); }
.step-nav > div { width: min(100% - 24px, 920px); min-width: 560px; min-height: 64px; margin: 0 auto; display: flex; align-items: center; gap: 18px; }
.step-nav span { flex: 0 0 auto; color: var(--brand-dark); font-size: 13px; font-weight: 900; }
.step-nav ol { display: flex; gap: 8px; margin: 0; padding: 0; list-style: none; }
.step-nav a { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 50%; background: var(--brand-soft); color: var(--brand-dark); font-size: 13px; font-weight: 900; text-decoration: none; }
.step-nav a:active, .step-nav a:focus-visible { background: var(--brand); color: #fff; outline: 2px solid var(--brand-dark); outline-offset: 2px; }

.steps { width: min(100% - 24px, 920px); margin: 0 auto; padding: 24px 0 18px; }
.image-note { margin: 0 4px 16px; color: var(--muted); font-size: 13px; text-align: center; }
.step-card { scroll-margin-top: 88px; margin-bottom: 18px; padding: 20px 16px 16px; border: 1px solid var(--line); border-radius: 18px; background: var(--paper); box-shadow: 0 8px 24px rgba(26,50,36,.06); }
.step-heading { display: flex; align-items: center; gap: 13px; }
.step-heading > span { width: 46px; height: 46px; flex: 0 0 46px; display: grid; place-items: center; border-radius: 13px; background: var(--brand-dark); color: #fff; font-size: 17px; font-weight: 900; }
.step-heading p { margin: 0 0 1px; color: var(--brand); font-size: 12px; font-weight: 900; letter-spacing: .06em; }
.step-heading h2 { margin: 0; font-size: 21px; line-height: 1.35; letter-spacing: -.025em; }
.instruction { margin: 14px 0 16px; font-size: 16px; line-height: 1.75; }
.step-image { position: relative; display: block; overflow: hidden; border: 1px solid #d3ded5; border-radius: 12px; background: #e8eee9; text-decoration: none; }
.step-image img { width: 100%; height: auto; aspect-ratio: 2 / 1; object-fit: cover; }
.step-image span { position: absolute; right: 8px; bottom: 8px; padding: 6px 10px; border-radius: 999px; background: rgba(21,62,43,.92); color: #fff; font-size: 12px; font-weight: 800; box-shadow: 0 4px 14px rgba(0,0,0,.18); }
.done-check { width: fit-content; min-height: 44px; margin: 10px 0 -6px auto; display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 14px; font-weight: 800; cursor: pointer; }
.done-check input { width: 22px; height: 22px; margin: 0; accent-color: var(--brand); }
.done-check:has(input:checked) { color: var(--brand-dark); }
.step-card-final { border-color: #9dcba0; }
.step-card-final .step-heading > span { background: var(--brand); }

.complete-card { width: min(100% - 24px, 920px); margin: 6px auto 42px; padding: 34px 20px; border-radius: 20px; background: var(--brand-dark); color: #fff; text-align: center; }
.complete-card > span { width: 48px; height: 48px; margin: 0 auto 12px; display: grid; place-items: center; border-radius: 50%; background: var(--brand); font-size: 26px; font-weight: 900; }
.complete-card > p:first-of-type { margin: 0; color: #a9dea9; font-size: 12px; font-weight: 900; letter-spacing: .13em; }
.complete-card h2 { margin: 4px 0 8px; font-size: 28px; }
.complete-card p:last-of-type { max-width: 620px; margin: 0 auto; color: #e2ece4; }
.complete-card a { min-height: 44px; margin-top: 18px; display: inline-flex; align-items: center; justify-content: center; color: #fff; font-weight: 800; text-underline-offset: 4px; }

footer { min-height: 88px; display: flex; align-items: center; justify-content: center; gap: 9px; padding: 20px 16px calc(20px + env(safe-area-inset-bottom)); border-top: 1px solid var(--line); background: #fff; }
footer img { width: 36px; height: 36px; border-radius: 50%; object-fit: cover; object-position: center; }
footer div { display: grid; line-height: 1.2; }
footer strong { color: var(--brand-dark); }
footer small { margin-top: 4px; color: var(--muted); font-size: 11px; }

@media (min-width: 760px) {
  .guide-header { padding-left: max(30px, calc((100vw - 920px) / 2)); padding-right: max(30px, calc((100vw - 920px) / 2)); }
  .intro-inner { padding: 64px 0 54px; }
  .lead { font-size: 19px; }
  .reward-card { max-width: 660px; }
  .steps { padding-top: 34px; }
  .step-card { padding: 28px; border-radius: 22px; }
  .step-heading > span { width: 54px; height: 54px; flex-basis: 54px; font-size: 19px; }
  .step-heading h2 { font-size: 26px; }
  .instruction { margin-left: 67px; font-size: 17px; }
  .done-check { margin-top: 14px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}