/* Green Channel Web 風ドキュメント用（公式サイトとは無関係・インスパイアのみ） */
:root {
  --gch-green: #129954;
  --gch-green-dark: #0d7a3d;
  --gch-orange: #ff8534;
  --gch-bg: #f4f4f4;
  --gch-card: #fff;
  --gch-border: #e1e1e1;
  --gch-text: #333;
  --gch-muted: #666;
  --gch-lead-en: #888;
  --radius: 4px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 62.5%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Roboto", "Hiragino Sans", "Hiragino Kaku Gothic ProN", Meiryo,
    sans-serif;
  font-size: 1.6rem;
  line-height: 1.75;
  color: var(--gch-text);
  background: var(--gch-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--gch-green-dark);
  text-decoration: underline;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--gch-orange);
}

.site-header {
  background: linear-gradient(
    135deg,
    var(--gch-green) 0%,
    var(--gch-green-dark) 100%
  );
  color: #fff;
  padding: 1.6rem 2rem 2rem;
  box-shadow: var(--shadow);
}

.site-header__inner {
  max-width: 960px;
  margin: 0 auto;
}

.site-header__brand {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  flex-wrap: wrap;
}

.site-header__logo {
  width: 48px;
  height: 48px;
  padding: 0;
  background: transparent;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
}

.site-header__logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  border-radius: var(--radius);
}

.site-header__titles h1 {
  margin: 0;
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.3;
}

.site-header__titles p {
  margin: 0.4rem 0 0;
  font-size: 1.3rem;
  opacity: 0.92;
}

.site-nav {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 2rem;
  background: var(--gch-card);
  border-bottom: 1px solid var(--gch-border);
}

.site-nav ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0;
}

.site-nav a {
  display: block;
  padding: 1rem 1.6rem;
  color: var(--gch-text);
  text-decoration: none;
  font-size: 1.4rem;
  border-bottom: 3px solid transparent;
}

.site-nav a:hover {
  color: var(--gch-green);
}

.site-nav a[aria-current="page"] {
  color: var(--gch-green-dark);
  font-weight: 700;
  border-bottom-color: var(--gch-orange);
}

main {
  flex: 1;
  max-width: 960px;
  width: 100%;
  margin: 0 auto;
  padding: 2.4rem 2rem 4rem;
}

.c-lead {
  margin: 0 0 2rem;
  font-size: 2rem;
  font-weight: 700;
  color: var(--gch-text);
  padding-bottom: 0.8rem;
  border-bottom: 2px solid var(--gch-green);
}

.c-lead__en {
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--gch-lead-en);
  margin-left: 0.6rem;
}

.c-card {
  background: var(--gch-card);
  border: 1px solid var(--gch-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2.4rem 2.8rem;
  margin-bottom: 2rem;
}

.c-card h2 {
  margin: 2rem 0 1rem;
  font-size: 1.8rem;
  color: var(--gch-green-dark);
  padding-left: 1rem;
  border-left: 4px solid var(--gch-orange);
  line-height: 1.4;
}

.c-card h2:first-child {
  margin-top: 0;
}

.c-card h3 {
  margin: 1.6rem 0 0.8rem;
  font-size: 1.5rem;
  color: var(--gch-text);
}

.c-card p,
.c-card li {
  margin: 0.8rem 0;
}

.c-card ul {
  padding-left: 2rem;
}

.c-card li {
  margin: 0.5rem 0;
}

.c-card code {
  background: #f0f0f0;
  padding: 0.15rem 0.45rem;
  border-radius: 3px;
  font-size: 0.92em;
  border: 1px solid var(--gch-border);
}

.c-note {
  background: #fff8f0;
  border: 1px solid #ffe0c2;
  border-radius: var(--radius);
  padding: 1.2rem 1.6rem;
  font-size: 1.4rem;
  margin: 1.6rem 0;
}

.c-note strong {
  color: var(--gch-orange);
}

.c-btn-row {
  margin-top: 2rem;
}

.c-btn {
  display: inline-block;
  padding: 0.9rem 2rem;
  background: var(--gch-green);
  color: #fff !important;
  text-decoration: none !important;
  border-radius: var(--radius);
  font-size: 1.4rem;
  font-weight: 700;
  box-shadow: 0 2px 0 var(--gch-green-dark);
}

.c-btn:hover {
  background: var(--gch-green-dark);
  color: #fff !important;
}

.site-footer {
  background: #2a2a2a;
  color: #ccc;
  padding: 2.4rem 2rem;
  font-size: 1.3rem;
  margin-top: auto;
}

.site-footer__inner {
  max-width: 960px;
  margin: 0 auto;
}

.site-footer p {
  margin: 0.6rem 0;
}

.site-footer a {
  color: #9fd4b8;
}

.site-footer a:hover {
  color: #fff;
}

@media (max-width: 600px) {
  .site-header__titles h1 {
    font-size: 1.8rem;
  }

  .c-card {
    padding: 1.6rem 1.4rem;
  }
}