:root {
  --ink: #10243b;
  --ink-soft: #40566a;
  --foam: #f7fbf8;
  --paper: #ffffff;
  --ocean: #0b7f93;
  --ocean-deep: #075768;
  --leaf: #205c3a;
  --coral-dark: #cb3e26;
  --sun: #f2c96d;
  --line: rgba(16, 36, 59, 0.14);
  --shadow: 0 18px 45px rgba(15, 46, 58, 0.15);
  --header-height: 68px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-height) + 18px); }
body {
  margin: 0;
  color: var(--ink);
  background: var(--foam);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", "Noto Sans JP", sans-serif;
  line-height: 1.75;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 3px solid var(--sun); outline-offset: 3px; }
[hidden] { display: none !important; }

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 16px;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(16, 36, 59, 0.1);
  backdrop-filter: blur(14px);
}
.brand { display: inline-flex; align-items: center; min-width: 0; }
.brand img { width: 152px; height: 43px; object-fit: contain; }
.desktop-nav { display: none; }
.header-link {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 15px;
  border-radius: 8px;
  color: var(--ocean-deep);
  background: var(--sun);
  border: 1px solid rgba(7, 87, 104, 0.24);
  font-size: 14px;
  font-weight: 800;
  box-shadow: 0 8px 20px rgba(7, 87, 104, 0.14);
}

.guide-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-height) + 46px) 20px 64px;
  color: #fff;
  background:
    radial-gradient(circle at 88% 18%, rgba(242, 201, 109, 0.28), transparent 28%),
    linear-gradient(135deg, #075768 0%, #0b7f93 68%, #205c3a 100%);
}
.guide-hero::after {
  content: "";
  position: absolute;
  width: 310px;
  height: 310px;
  right: -150px;
  bottom: -190px;
  border: 54px solid rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  pointer-events: none;
}
.hero-inner {
  width: min(100%, 1080px);
  margin: 0 auto;
  display: grid;
  gap: 34px;
  position: relative;
  z-index: 1;
}
.breadcrumbs { margin: 0 0 20px; color: rgba(255, 255, 255, 0.76); font-size: 12px; font-weight: 700; }
.breadcrumbs a { text-decoration: underline; text-underline-offset: 3px; }
.eyebrow { margin: 0 0 10px; color: #ffe292; font-size: 13px; font-weight: 900; }
h1, h2, h3, p { overflow-wrap: anywhere; }
h1 { margin: 0; color: #fff8df; font-size: clamp(38px, 10vw, 68px); line-height: 1.1; font-weight: 900; }
.hero-lead { max-width: 610px; margin: 18px 0 0; color: rgba(255, 255, 255, 0.9); font-size: 16px; font-weight: 650; }
.hero-note { margin: 15px 0 0; color: rgba(255, 255, 255, 0.72); font-size: 12px; }

.calculator {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.98);
  border: 1px solid rgba(255, 255, 255, 0.7);
  border-radius: 16px;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.calculator-head { padding: 24px 24px 0; }
.calculator-head p { margin: 0; color: var(--ocean); font-size: 13px; font-weight: 900; }
.calculator-head h2 { margin: 4px 0 0; font-size: 25px; line-height: 1.35; }
.calculator-form { display: grid; gap: 16px; padding: 22px 24px 24px; }
.field-grid { display: grid; grid-template-columns: minmax(0, 1fr) 96px; gap: 12px; }
.field { display: grid; gap: 7px; }
.field span { color: var(--ink-soft); font-size: 13px; font-weight: 800; }
.field input, .field select {
  width: 100%;
  min-height: 50px;
  padding: 0 13px;
  border: 1px solid rgba(16, 36, 59, 0.24);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
}
.field input:focus, .field select:focus { border-color: var(--ocean); }
.calculate-button {
  min-height: 52px;
  border: 0;
  border-radius: 8px;
  color: #fff;
  background: var(--ocean-deep);
  font-weight: 850;
  cursor: pointer;
  box-shadow: 0 10px 24px rgba(7, 87, 104, 0.2);
}
.calculate-button:active { transform: translateY(1px); }

.result { padding: 24px; border-top: 1px solid var(--line); background: #f2f7f4; }
.result-label { margin: 0; color: var(--leaf); font-size: 12px; font-weight: 900; }
.result-value {
  display: block;
  margin-top: 2px;
  color: var(--coral-dark);
  font-size: 38px;
  line-height: 1.2;
  font-weight: 900;
}
.result-range { margin: 7px 0 0; color: var(--ink-soft); font-size: 13px; }
.formula-results { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 18px; }
.formula-result { padding: 12px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.formula-result span { display: block; color: var(--ink-soft); font-size: 11px; font-weight: 700; }
.formula-result strong { display: block; margin-top: 2px; color: var(--ink); font-size: 17px; }
.result-empty { padding: 24px; border-top: 1px solid var(--line); color: var(--ink-soft); background: #f2f7f4; }

.content-section { padding: 64px 20px; background: var(--paper); }
.content-section--soft { background: #eef5f0; }
.content-inner { width: min(100%, 860px); margin: 0 auto; }
.section-label { margin: 0 0 7px; color: var(--ocean); font-size: 13px; font-weight: 900; }
.section-title { margin: 0; font-size: clamp(30px, 7vw, 44px); line-height: 1.35; font-weight: 900; }
.section-lead { max-width: 690px; margin: 15px 0 0; color: var(--ink-soft); }
.explain-grid { display: grid; gap: 14px; margin-top: 28px; }
.explain-card {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--foam);
}
.explain-card h3 { margin: 0; color: var(--leaf); font-size: 19px; }
.explain-card p { margin: 8px 0 0; color: var(--ink-soft); font-size: 14px; }
.formula {
  display: block;
  margin-top: 12px;
  padding: 11px 13px;
  border-left: 3px solid var(--sun);
  color: var(--ink);
  background: #fff;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
  overflow-x: auto;
}

.table-wrap { margin-top: 28px; overflow-x: auto; border: 1px solid var(--line); border-radius: 12px; background: #fff; }
.load-table { width: 100%; border-collapse: collapse; }
.load-table th, .load-table td { padding: 14px 18px; text-align: left; border-bottom: 1px solid var(--line); }
.load-table thead th { color: var(--ink); background: #f2f7f4; font-size: 13px; }
.load-table tbody th { color: var(--ocean-deep); font-weight: 900; }
.load-table tbody tr:last-child th, .load-table tbody tr:last-child td { border-bottom: 0; }
.table-note { margin: 12px 0 0; color: var(--ink-soft); font-size: 12px; }

.safety-list { margin: 24px 0 0; padding: 0; list-style: none; }
.safety-list li { padding: 16px 0 16px 30px; border-top: 1px solid var(--line); position: relative; }
.safety-list li:last-child { border-bottom: 1px solid var(--line); }
.safety-list li::before { content: "✓"; position: absolute; left: 4px; color: var(--leaf); font-weight: 900; }
.source-list { margin: 24px 0 0; padding-left: 20px; color: var(--ink-soft); font-size: 13px; }
.source-list li + li { margin-top: 10px; }
.source-list a { color: var(--ocean-deep); text-decoration: underline; text-underline-offset: 3px; }

.app-band { padding: 68px 20px; color: #fff; background: var(--ocean-deep); }
.app-inner { width: min(100%, 860px); margin: 0 auto; display: grid; gap: 28px; align-items: center; }
.app-band .section-label { color: #ffe292; }
.app-band .section-title { color: #fff8df; }
.app-band .section-lead { color: rgba(255, 255, 255, 0.84); }
.store-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 200px;
  height: 64px;
  border-radius: 8px;
}
.store-link img { width: 180px; max-width: none; }
.store-note { margin: 8px 0 0; color: rgba(255, 255, 255, 0.68); font-size: 12px; }

footer { padding: 28px 20px; background: var(--foam); border-top: 1px solid var(--line); }
.footer-inner { width: min(100%, 1080px); margin: 0 auto; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 18px; }
.footer-logo { width: 170px; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 16px; color: var(--ink-soft); font-size: 12px; font-weight: 750; }
.footer-copy { margin: 0; color: var(--ink-soft); font-size: 12px; }

@media (min-width: 760px) {
  :root { --header-height: 76px; }
  .site-header { padding: 12px 5vw; }
  .desktop-nav { display: flex; align-items: center; gap: 24px; margin-left: auto; font-size: 13px; font-weight: 800; }
  .guide-hero { padding: calc(var(--header-height) + 70px) 5vw 84px; }
  .hero-inner { grid-template-columns: minmax(0, 1fr) minmax(400px, 0.78fr); gap: 64px; align-items: center; }
  .content-section { padding: 88px 5vw; }
  .explain-grid { grid-template-columns: 1fr 1fr; }
  .app-band { padding: 88px 5vw; }
  .app-inner { grid-template-columns: 1fr auto; }
  footer { padding: 30px 5vw; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}