/* ============================================
   アプリ公開用サイト — 共通スタイル
   シンプル・読みやすさ・モバイル対応を優先
   ============================================ */

:root {
  --color-bg: #ffffff;
  --color-text: #1f2937;
  --color-text-muted: #6b7280;
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-border: #e5e7eb;
  --color-bg-subtle: #f9fafb;
  --max-width: 720px;
  --radius: 8px;
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans",
    "Hiragino Kaku Gothic ProN", "Noto Sans JP", Meiryo, sans-serif;
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 32px 20px 80px;
}

/* ヘッダー */
header.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
  position: sticky;
  top: 0;
  z-index: 10;
}

header.site-header .container {
  padding-top: 16px;
  padding-bottom: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

header.site-header a.logo {
  font-weight: 700;
  font-size: 18px;
  color: var(--color-text);
  text-decoration: none;
}

header.site-header nav {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

header.site-header nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 14px;
}

header.site-header nav a:hover {
  color: var(--color-primary);
}

/* 見出し */
h1 {
  font-size: 28px;
  line-height: 1.4;
  margin: 0 0 8px;
}

h2 {
  font-size: 20px;
  line-height: 1.5;
  margin: 40px 0 12px;
  padding-top: 8px;
  border-top: 1px solid var(--color-border);
}

h2:first-of-type {
  border-top: none;
  padding-top: 0;
}

h3 {
  font-size: 17px;
  margin: 24px 0 8px;
}

/* 段落・リスト */
p {
  margin: 12px 0;
}

ul, ol {
  padding-left: 24px;
  margin: 12px 0;
}

li {
  margin: 6px 0;
}

/* リンク */
a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 2px;
}

a:hover {
  color: var(--color-primary-hover);
}

/* メタ情報 */
.meta {
  color: var(--color-text-muted);
  font-size: 14px;
  margin-bottom: 32px;
}

/* ボックス */
.box {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 24px 0;
}

/* フッター */
footer.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 20px;
  color: var(--color-text-muted);
  font-size: 14px;
  text-align: center;
}

footer.site-footer nav {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

footer.site-footer nav a {
  color: var(--color-text-muted);
}

/* ヒーロー(トップページ用) */
.hero {
  text-align: center;
  padding: 48px 0 32px;
}

.hero h1 {
  font-size: 36px;
  margin-bottom: 16px;
}

.hero .tagline {
  font-size: 18px;
  color: var(--color-text-muted);
  margin-bottom: 32px;
}

.badges {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin: 24px 0;
}

.badge {
  display: inline-block;
  padding: 12px 24px;
  background: var(--color-text);
  color: #fff;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: 500;
}

.badge:hover {
  color: #fff;
  opacity: 0.9;
}

/* FAQ */
details {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 12px 0;
}

details[open] {
  background: var(--color-bg-subtle);
}

summary {
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary::before {
  content: "＋";
  margin-right: 8px;
  color: var(--color-primary);
}

details[open] summary::before {
  content: "−";
}

/* レスポンシブ */
@media (max-width: 480px) {
  .container {
    padding: 24px 16px 64px;
  }

  h1 {
    font-size: 24px;
  }

  .hero h1 {
    font-size: 28px;
  }

  .hero .tagline {
    font-size: 16px;
  }
}