* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Yu Gothic", "Hiragino Kaku Gothic ProN", Meiryo, system-ui, sans-serif;
  color: #263238;
  background: #f6f8f7;
  line-height: 1.8;
}

.hero {
  background:
    radial-gradient(circle at top left, rgba(177, 215, 204, 0.65), transparent 34%),
    linear-gradient(135deg, #edf5f1 0%, #f8faf7 52%, #eef2f7 100%);
  border-bottom: 1px solid #d9e3df;
}

.hero-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 70px 22px 58px;
}

.eyebrow {
  margin: 0 0 8px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #5e7f76;
  font-size: 0.82rem;
}

h1 {
  margin: 0 0 16px;
  font-size: clamp(2.2rem, 5vw, 4.2rem);
  line-height: 1.05;
  color: #304b45;
}

.lead {
  max-width: 760px;
  font-size: 1.1rem;
  color: #42544f;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.button {
  display: inline-block;
  padding: 12px 20px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  border: 1px solid #9eb6ae;
}

.button.primary {
  background: #5d847b;
  color: white;
  border-color: #5d847b;
}

.button.secondary {
  color: #4f6e67;
  background: rgba(255,255,255,0.55);
}

main {
  max-width: 980px;
  margin: 34px auto;
  padding: 0 18px;
}

.card {
  background: white;
  border: 1px solid #e1e7e4;
  border-radius: 18px;
  padding: 28px;
  margin: 22px 0;
  box-shadow: 0 10px 30px rgba(30, 50, 45, 0.05);
}

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

h2 {
  margin: 0 0 14px;
  color: #38544e;
  font-size: 1.45rem;
  border-left: 6px solid #9fc6bb;
  padding-left: 12px;
}

h3 {
  margin-top: 28px;
  color: #3f5f57;
}

.checklist { padding-left: 1.2em; }
.checklist li { margin: 8px 0; }

.csv-sample-wrap {
  margin: 20px 0;
  padding: 12px;
  background: #f8fbfa;
  border: 1px solid #dbe7e3;
  border-radius: 14px;
  overflow-x: auto;
}

.csv-sample {
  min-width: 1180px;
  width: 100%;
  border-collapse: collapse;
  background: white;
  font-size: 0.88rem;
}

.csv-sample th {
  background: #dfeee9;
  color: #253d37;
  white-space: nowrap;
}

.csv-sample td,
.csv-sample th {
  border: 1px solid #cbd9d5;
  padding: 8px 9px;
  vertical-align: top;
}

.csv-sample tbody tr:nth-child(even) {
  background: #f6faf8;
}

.table-wrap { overflow-x: auto; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0 22px;
  font-size: 0.95rem;
}

th, td {
  border: 1px solid #dbe4e0;
  padding: 10px;
  vertical-align: top;
}

th {
  background: #edf5f1;
  color: #314d46;
}

code {
  background: #eef3f1;
  padding: 0.1em 0.35em;
  border-radius: 5px;
  font-family: Consolas, Menlo, monospace;
}

.note {
  margin-top: 18px;
  padding: 14px 16px;
  border-left: 5px solid #7fa99f;
  background: #f1f7f5;
  border-radius: 10px;
}

.steps { padding-left: 1.4em; }
.steps li { margin: 8px 0; }

.center {
  text-align: center;
  margin-top: 24px;
}

footer {
  text-align: center;
  color: #6a7a76;
  padding: 32px 16px 46px;
}

@media (max-width: 760px) {
  .grid { grid-template-columns: 1fr; }
  .card { padding: 22px; }
}