* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: "Segoe UI", Arial, sans-serif;
  background: #fafaf8;
  color: #1a1a1a;
  line-height: 1.75;
}

#site-header {
  text-align: center;
  padding: 60px 24px 40px;
  border-bottom: 1px solid #e0e0d8;
  background: #fff;
}

#site-header h1 {
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: #111;
  margin-bottom: 10px;
}

.byline {
  font-size: 0.95rem;
  color: #777;
  font-family: "Segoe UI", Arial, sans-serif;
}

#narrative {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px 80px;
}

.section {
  padding: 56px 0 0;
  border-top: 1px solid #e8e8e0;
  margin-top: 56px;
}

.section:first-child {
  border-top: none;
  margin-top: 0;
  padding-top: 56px;
}

.rq-title {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.4;
  color: #111;
  margin-bottom: 18px;
  font-family: "Segoe UI", Arial, sans-serif;
}

.body-text {
  font-size: 1.05rem;
  color: #333;
  margin-bottom: 28px;
}

.chart-bare {
  width: 100%;
  margin: 0 0 12px 0;
  margin-top: 24px;
}

.chart-bare iframe {
  width: 100%;
  border: none;
  display: block;
}

.intro-section,
.conclusion-section {
  padding-top: 48px;
}

.conclusion-section .rq-title {
  margin-bottom: 16px;
}

.rq1-switcher {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}

.rq1-btn {
  padding: 7px 18px;
  border: 1px solid #ccc;
  border-radius: 6px;
  background: #fff;
  font-size: 0.88rem;
  cursor: pointer;
  font-family: "Segoe UI", Arial, sans-serif;
  transition: background 0.15s, border-color 0.15s;
}

.rq1-btn:hover {
  background: #f0f4ff;
}

.rq1-btn.active {
  background: #dbeafe;
  border-color: #93c5fd;
  font-weight: 600;
}

#site-footer {
  text-align: center;
  padding: 32px 24px;
  border-top: 1px solid #e0e0d8;
  font-size: 0.85rem;
  color: #999;
  font-family: "Segoe UI", Arial, sans-serif;
  background: #fff;
}

@media (max-width: 600px) {
  #site-header h1 {
    font-size: 1.6rem;
  }
  .rq-title {
    font-size: 1.1rem;
  }
}