:root {
  --primary-color: #0f766e;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-color: #334155;
  --border-color: #e2e8f0;
}

body {
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "メイリオ", sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  margin: 0;
  padding: 0;
  line-height: 1.6;
}

.guide-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 20px;
}

.guide-header {
  background: linear-gradient(135deg, #0f766e, #115e59);
  color: #fff;
  padding: 30px 0;
  margin-bottom: 20px;
  text-align: center;
}

.guide-header h1 {
  margin: 0 0 10px 0;
  font-size: 1.8rem;
}

.guide-header p {
  margin: 0;
  opacity: 0.9;
  font-size: 0.95rem;
}

.guide-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 25px;
  margin-bottom: 20px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.guide-card h2 {
  font-size: 1.3rem;
  color: var(--primary-color);
  margin-top: 0;
  border-bottom: 2px solid #f1f5f9;
  padding-bottom: 8px;
}

.highlight-box {
  background-color: #f0fdf4;
  border-color: #bbf7d0;
}

.step-list {
  padding-left: 0;
  list-style: none;
}

.step-list li {
  margin-bottom: 20px;
  padding-left: 15px;
  border-left: 4px solid var(--primary-color);
}

.step-list h3 {
  margin: 0 0 5px 0;
  font-size: 1.05rem;
}

.code-block {
  background: #1e293b;
  color: #f8fafc;
  padding: 12px;
  border-radius: 6px;
  font-family: monospace;
  font-size: 0.85rem;
  overflow-x: auto;
  margin-bottom: 15px;
}

.guide-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 10px;
  font-size: 0.9rem;
}

.guide-table th, .guide-table td {
  border: 1px solid var(--border-color);
  padding: 8px 12px;
  text-align: left;
}

.guide-table th {
  background-color: #f1f5f9;
}

.faq-item {
  margin-bottom: 15px;
}

.faq-item h4 {
  margin: 0 0 5px 0;
  color: #1e293b;
}

.guide-footer-btn {
  text-align: center;
  margin: 30px 0;
}

.btn-close {
  background-color: #64748b;
  color: #fff;
  border: none;
  padding: 10px 24px;
  font-size: 1rem;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.2s;
}

.btn-close:hover {
  background-color: #475569;
}