/* RDB 入門ガイド */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Noto Sans JP", "Yu Gothic", "Meiryo", sans-serif;
  line-height: 1.8;
  color: #263238;
  background: #f7f7fb;
}
a { color: #3f51b5; text-decoration: none; }
a:hover { color: #2d3f98; text-decoration: underline; }

.site-header {
  background: linear-gradient(135deg, #283593 0%, #3949ab 100%);
  color: #fff;
  padding: 1rem 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
  position: sticky;
  top: 0;
  z-index: 100;
}
.site-header a { color: #cfd8ff; }
.site-header a:hover { color: #edf0ff; text-decoration: none; }
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.brand-group { display: flex; align-items: center; gap: 0.75rem; }
.site-logo-link { width: 40px; height: 40px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; }
.site-logo { width: 40px; height: 40px; display: block; }
.site-title { font-size: 1.3rem; font-weight: 700; letter-spacing: 0.02em; color: #fff; }
.site-title small { font-size: 0.75rem; font-weight: 400; opacity: 0.82; margin-left: 0.5rem; color: #cfd8ff; }
.header-nav { display: flex; gap: 1.2rem; font-size: 0.9rem; }

.page-wrapper { max-width: 1200px; margin: 0 auto; display: flex; gap: 2rem; padding: 2rem; }
.sidebar { width: 280px; flex-shrink: 0; }
.main-content { flex: 1; min-width: 0; background: #fff; border-radius: 8px; padding: 2.3rem; box-shadow: 0 1px 4px rgba(0,0,0,0.07); }

.toc { position: sticky; top: 5rem; background: #fff; border-radius: 8px; padding: 1.2rem; box-shadow: 0 1px 4px rgba(0,0,0,0.07); max-height: calc(100vh - 6rem); overflow-y: auto; }
.toc h2 { font-size: 0.9rem; color: #3f51b5; border-bottom: 2px solid #9fa8ff; padding-bottom: 0.5rem; margin-bottom: 0.8rem; }
.toc ul { list-style: none; }
.toc li { margin-bottom: 0.3rem; }
.toc a { display: block; padding: 0.25rem 0.5rem; font-size: 0.86rem; color: #4e5968; border-radius: 4px; }
.toc a:hover { background: #eef1ff; color: #3f51b5; text-decoration: none; }

.main-content h1 { font-size: 1.8rem; color: #1f2a62; border-bottom: 3px solid #9fa8ff; padding-bottom: 0.5rem; margin-bottom: 1.3rem; }
.main-content h2 { font-size: 1.35rem; color: #2d3748; margin-top: 2.2rem; margin-bottom: 0.9rem; padding-left: 0.8rem; border-left: 4px solid #9fa8ff; }
.main-content h3 { font-size: 1.1rem; color: #3c4758; margin-top: 1.5rem; margin-bottom: 0.65rem; }
.main-content p { margin-bottom: 0.9rem; }
.main-content ul, .main-content ol { margin-bottom: 1rem; padding-left: 1.5rem; }
.main-content li { margin-bottom: 0.3rem; }
.lead { font-size: 1.05rem; color: #4b5563; margin-bottom: 1.5rem; }

.badge { display: inline-block; padding: 0.22rem 0.58rem; border-radius: 999px; font-size: 0.76rem; font-weight: 700; margin-right: 0.4rem; margin-bottom: 0.45rem; }
.badge-rdb { background: #e9ecff; color: #3f51b5; }
.badge-design { background: #e8f5e9; color: #2e7d32; }
.badge-normalize { background: #fff3e0; color: #e65100; }

pre { background: #1f253a; color: #e5e9ff; border-radius: 6px; padding: 1.1rem 1.3rem; overflow-x: auto; margin-bottom: 1.2rem; font-size: 0.88rem; line-height: 1.6; border-left: 4px solid #9fa8ff; }
code { font-family: "JetBrains Mono", "Source Code Pro", "Consolas", monospace; font-size: 0.9em; background: #eef1ff; padding: 0.1rem 0.3rem; border-radius: 4px; }
pre code { background: transparent; padding: 0; }

table { width: 100%; border-collapse: collapse; margin-bottom: 1.2rem; font-size: 0.95rem; }
th, td { border: 1px solid #dbe2ef; padding: 0.55rem 0.7rem; text-align: left; }
th { background: #f2f6fc; }

.info-box { border-left: 4px solid; border-radius: 6px; padding: 0.9rem 1rem; margin: 1rem 0 1.2rem; }
.note { background: #eef4ff; border-color: #4f83f3; }
.tip { background: #eefbf3; border-color: #2ea86b; }
.warning { background: #fff8eb; border-color: #d08a27; }

.card-grid { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); margin-top: 1rem; }
.card { border: 1px solid #dde4ef; border-radius: 10px; padding: 0.9rem; background: linear-gradient(180deg, #ffffff 0%, #fafcff 100%); }
.card h3 { margin: 0 0 0.4rem 0; font-size: 1.03rem; }
.card p { margin: 0; color: #526072; font-size: 0.9rem; line-height: 1.65; }
.card-number { display: inline-block; min-width: 1.6rem; padding: 0.1rem 0.45rem; margin-bottom: 0.4rem; border-radius: 999px; background: #e9ecff; color: #3f51b5; font-size: 0.75rem; font-weight: 700; }

.nf-step {
  display: inline-block;
  font-weight: 700;
  color: #2d3f98;
  background: #e9ecff;
  border: 1px solid #c8d1ff;
  border-radius: 999px;
  padding: 0.1rem 0.6rem;
  margin-bottom: 0.6rem;
  font-size: 0.83rem;
}

.er-figure {
  background: #f6f8ff;
  border: 1px solid #dfe6ff;
  border-radius: 8px;
  padding: 0.8rem;
  margin-bottom: 1.2rem;
}

.er-figure svg {
  width: 100%;
  height: auto;
  display: block;
}

.er-caption {
  font-size: 0.85rem;
  color: #4b5563;
  margin-top: 0.5rem;
}

.site-footer { text-align: center; color: #4a5660; font-size: 0.88rem; padding: 2rem 1rem; }

@media (max-width: 1000px) {
  .page-wrapper { flex-direction: column; }
  .sidebar { width: 100%; }
  .toc { position: static; max-height: none; }
}
@media (max-width: 640px) {
  .site-header { padding: 0.85rem 1rem; }
  .page-wrapper { padding: 1rem; gap: 1rem; }
  .main-content { padding: 1.3rem; }
  .site-title small { display: block; margin-left: 0; }
}