/* === 基本スタイル === */
html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: #fff;
  color: #555;
  font-family: 'Helvetica Neue', sans-serif;
}

/* === レイアウト === */
.container {
  display: flex;
  flex-wrap: wrap;
  min-height: 100vh;
}

.sidebar {
  width: 150px;
  background-color: #ea533a;
  padding: 0.5em 8px 0;
  position: fixed;
  top: 0;
  bottom: 0;
  overflow-y: auto;
}

.sidebar ul {
  list-style: none;
  padding: 0;
}

.sidebar li {
  margin: 1em 0;
  font-weight: bold;
  cursor: pointer;
}

.sidebar li a {
  color: #fff;
  text-decoration: none;
}

.content {
  flex: 1;
  min-width: 0;
  margin-left: 220px;
  padding: 0 20px;
  font-size: 1.1em;
  line-height: 1.6;
}

/* === セクション === */
.section {
  border-left: 4px solid #ea533a;
  padding-left: 1em;
  margin: 1.5em 0;
  background-color: rgba(234, 83, 58, 0.05);
  border-radius: 4px;
}

.content h1,
.content h2,
.content h3 {
  margin: 0 0 0.6em;
}

.content p,
.content ul,
.content ol {
  font-size: 1em;
  line-height: 1.6;
  margin: 0.6em 0;
}

.content li {
  line-height: 1.6;
  margin-bottom: 0.4em;
}

/* === 補助要素 === */
.highlight {
  text-decoration: underline;
  font-weight: bold;
}

.contact {
  margin-top: 0.2em;
  font-size: 0.9em;
}

#language-switcher {
  margin-top: 1em;
}

#lang-btn {
  background-color: #ea533a;
  color: #fff;
  border: none;
  padding: 0.4em 1em;
  cursor: pointer;
  border-radius: 5px;
}

footer {
  text-align: right;
  font-size: 0.85em;
  color: #999;
  padding: 0.5em 1em;
  margin: 3em 0 2em;
}

.no-underline {
  text-decoration: none;
}

/* === カスタムボタン === */
.custom-button {
  display: inline-block;
  font-size: 75%;
  font-weight: bold;
  padding: 0.1em 0.5em;
  margin-left: 0.5em;
  vertical-align: middle;
  background-color: #fff;
  color: #e30f25;
  border: 1px solid #e30f25;
  border-radius: 0.4em;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.2s ease;
}

.custom-button:hover {
  background-color: #e30f25;
  color: #fff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.custom-button:active {
  background-color: #c70d20;
  border-color: #c70d20;
  box-shadow: 0 0 1px rgba(0, 0, 0, 0.1);
}

/* === レスポンシブ対応 === */
@media (max-width: 768px) {
  .sidebar {
    position: relative;
    width: 100%;
  }

  .content {
    margin-left: 0;
    padding: 1em;
  }

  .menu-toggle {
    display: block;
    background-color: #ea533a;
    color: #fff;
    border: none;
    padding: 0.5em 1em;
    font-size: 1em;
    font-weight: bold;
    cursor: pointer;
    width: 100%;
    text-align: left;
  }
}

/* === サイドバー切り替え用 === */
.sidebar.collapsed {
  display: none;
}

.menu-toggle {
  display: none;
}

/* === スマホ用メニューボタン === */
.menu-toggle {
  display: none; /* ← デフォルトは非表示（大画面用） */
}

@media (max-width: 768px) {
  .menu-toggle {
    display: block; /* ← 小画面では表示 */
    background-color: #ea533a;
    color: #fff;
    border: none;
    padding: 0.5em 1em;
    font-size: 1em;
    font-weight: bold;
    cursor: pointer;
    width: 100%;
    text-align: left;
  }

  .sidebar {
    position: relative;
    width: 100%;
  }

  .content {
    margin-left: 0;
    padding: 1em;
  }
}