:root {
  --bg: #ffffff;
  --surface: #f5f7fa;
  --border: #e4e8ee;
  --text: #1c2430;
  --text-secondary: #5b6472;
  --accent: #2f6fed;
  --accent-soft: rgba(47, 111, 237, 0.1);
  --max-width: 960px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Inter, system-ui, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.site-header .wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text);
}

.brand span {
  color: var(--accent);
}

.site-nav a {
  color: var(--text-secondary);
  font-weight: 600;
  margin-left: 1.5rem;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--accent);
  text-decoration: none;
}

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2.5rem 1.5rem 4rem;
}

.hero {
  padding: 3rem 0 2rem;
}

.hero h1 {
  font-size: 2.25rem;
  margin: 0 0 0.75rem;
}

.hero p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 640px;
}

.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 0.6rem 1.25rem;
  border-radius: 8px;
  font-weight: 600;
  margin-top: 1rem;
}

.btn:hover {
  text-decoration: none;
  opacity: 0.92;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
  margin-top: 1.5rem;
}

.card {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.5rem;
  background: var(--surface);
}

.card h3 {
  margin-top: 0;
}

.post-list {
  margin-top: 2rem;
  display: grid;
  gap: 1.5rem;
}

.post-list article {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.5rem;
}

.post-list h2 {
  margin: 0 0 0.4rem;
  font-size: 1.35rem;
}

.post-meta {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

article.post h1 {
  font-size: 2rem;
  margin-bottom: 0.25rem;
}

article.post .post-meta {
  margin-bottom: 2rem;
}

article.post h2 {
  margin-top: 2rem;
  font-size: 1.35rem;
}

article.post .faq-q {
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.table-wrap {
  overflow-x: auto;
  margin: 1.25rem 0;
}

table {
  border-collapse: collapse;
  width: 100%;
}

th,
td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.75rem;
  text-align: left;
}

th {
  background: var(--surface);
}

.ai-disclosure {
  margin-top: 2.5rem;
  padding: 1rem 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.site-footer .wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem;
}