/* --------------- 基本リセット --------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background: #0b1220; /* ちょいダーク */
  color: #e5e7eb;
  line-height: 1.7;
}

/* --------------- リンク --------------- */
a {
  color: #38bdf8;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* --------------- ヘッダー --------------- */
.site-header {
  border-bottom: 1px solid rgba(148, 163, 184, 0.3);
  background: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(10px);
  padding: 16px 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-title {
  font-size: 20px;
  font-weight: 600;
}

.site-subtitle {
  font-size: 12px;
  color: #9ca3af;
  margin-top: 4px;
}

/* --------------- コンテナ --------------- */
.container {
  max-width: 800px;
  margin: 24px auto 40px;
  padding: 0 16px;
}

/* --------------- 一覧セクション --------------- */
.section-title {
  font-size: 18px;
  margin-bottom: 16px;
  font-weight: 600;
}

.post-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.post-item {
  background: radial-gradient(circle at top left, #1f2937, #020617);
  border-radius: 12px;
  padding: 14px 16px;
  border: 1px solid rgba(148, 163, 184, 0.3);
  transition: transform 0.15s ease, box-shadow 0.15s ease,
    border-color 0.15s ease;
}

.post-item:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 35px rgba(15, 23, 42, 0.7);
  border-color: #38bdf8;
}

.post-item-title {
  font-size: 15px;
  font-weight: 500;
  margin-bottom: 4px;
  color: #e5e7eb;
}

.post-item-meta {
  font-size: 11px;
  color: #9ca3af;
}

/* --------------- 記事本文 --------------- */
.article-body {
  background: #020617;
  border-radius: 16px;
  padding: 24px 20px;
  border: 1px solid rgba(148, 163, 184, 0.4);
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.9);
}

/* markdownから生成される要素のスタイル */
.article-body h1 {
  font-size: 24px;
  margin-bottom: 12px;
}

.article-body h2 {
  font-size: 20px;
  margin: 24px 0 8px;
  border-bottom: 1px solid rgba(148, 163, 184, 0.5);
  padding-bottom: 4px;
}

.article-body h3 {
  font-size: 17px;
  margin: 18px 0 6px;
}

.article-body p {
  margin: 10px 0;
}

.article-body ul,
.article-body ol {
  padding-left: 1.3em;
  margin: 10px 0;
}

.article-body li {
  margin: 4px 0;
}

.article-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas,
    "Liberation Mono", "Courier New", monospace;
  font-size: 90%;
  background: rgba(15, 23, 42, 0.9);
  padding: 2px 4px;
  border-radius: 4px;
}

.article-body pre {
  background: #020617;
  padding: 12px;
  border-radius: 8px;
  overflow-x: auto;
  border: 1px solid rgba(148, 163, 184, 0.4);
}

/* --------------- フッター --------------- */
.site-footer {
  border-top: 1px solid rgba(148, 163, 184, 0.3);
  padding: 16px 24px;
  font-size: 11px;
  color: #9ca3af;
  text-align: center;
}

/* --------------- レスポンシブ微調整 --------------- */
@media (min-width: 768px) {
  .site-header,
  .site-footer {
    padding-left: 40px;
    padding-right: 40px;
  }

  .container {
    padding: 0 24px;
  }
}
.back-button {
  display: inline-block;
  margin-bottom: 16px;
  font-size: 14px;
  color: #38bdf8;
  text-decoration: none;
  padding: 6px 10px;
  border: 1px solid rgba(148, 163, 184, 0.3);
  border-radius: 6px;
  background: rgba(15, 23, 42, 0.5);
  transition: 0.15s ease;
}

.back-button:hover {
  background: rgba(56, 189, 248, 0.1);
  border-color: #38bdf8;
  text-decoration: none;
}
@media (max-width: 480px) {
  .site-title {
    font-size: 18px;
  }

  .site-subtitle {
    font-size: 11px;
  }

  .article-body {
    padding: 20px 14px;
  }

  .post-item {
    padding: 12px 14px;
  }
}

.post-item-summary {
  font-size: 13px;
  color: #d1d5db;
  margin-top: 6px;
}

.search-input {
  width: 100%;
  padding: 10px 12px;
  margin-bottom: 20px;
  background-color: #1f2937;
  border: 1px solid rgba(148, 163, 184, 0.3);
  border-radius: 8px;
  color: #e5e7eb;
  font-size: 14px;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.search-input:focus {
  outline: none;
  border-color: #38bdf8;
  box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.3);
}