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

:root {
  --bg-page: #f8fafc;
  --bg-surface: #ffffff;
  --bg-subtle: #f1f5f9;
  --bg-muted: #e2e8f0;
  --border-main: #e2e8f0;
  --border-strong: #cbd5e1;
  --text-strong: #0f172a;
  --text-main: #334155;
  --text-muted: #64748b;
  --indigo-600: #4f46e5;
  --indigo-700: #4338ca;
  --indigo-50: #eef2ff;
  --indigo-100: #e0e7ff;
  --emerald-600: #059669;
  --emerald-700: #047857;
  --emerald-50: #ecfdf5;
  --emerald-200: #a7f3d0;
  --amber-700: #b45309;
  --amber-50: #fffbeb;
  --amber-200: #fde68a;
  --rose-700: #be123c;
  --rose-50: #fff1f2;
  --rose-200: #fecdd3;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --shadow-sm: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 12px -2px rgba(15, 23, 42, 0.08);
  --max-width: 920px;
}

html {
  font-size: 15px;
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-page);
  color: var(--text-main);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", Meiryo, sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4 {
  color: var(--text-strong);
  line-height: 1.35;
  font-weight: 700;
  text-wrap: balance;
}

p, li, td, th {
  text-wrap: pretty;
  overflow-wrap: break-word;
}

a {
  color: var(--indigo-600);
  text-decoration: none;
  transition: color 0.15s ease, background-color 0.15s ease;
}

a:hover {
  color: var(--indigo-700);
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-main);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
}

.brand-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
}

.brand-title {
  font-size: 1.2rem;
  font-weight: 800;
  background: linear-gradient(90deg, #0f172a 0%, #4338ca 55%, #059669 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.brand-tag {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-full);
  background-color: var(--emerald-50);
  color: var(--emerald-700);
  border: 1px solid var(--emerald-200);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.nav-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
}

.nav-link:hover {
  color: var(--text-strong);
  background-color: var(--bg-subtle);
}

.nav-link.active {
  color: var(--indigo-700);
  background-color: var(--indigo-50);
}

/* Main container */
.main-container {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #ffffff 0%, #f1f5f9 100%);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-lg);
  padding: 2rem 1.75rem;
  box-shadow: var(--shadow-sm);
}

.hero-top {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.85rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0.25rem 0.7rem;
  border-radius: var(--radius-full);
}

.pill-emerald {
  background-color: var(--emerald-50);
  color: var(--emerald-700);
  border: 1px solid var(--emerald-200);
}

.pill-indigo {
  background-color: var(--indigo-50);
  color: var(--indigo-700);
  border: 1px solid var(--indigo-100);
}

.pill-slate {
  background-color: var(--bg-subtle);
  color: var(--text-main);
  border: 1px solid var(--border-strong);
}

.hero-title {
  font-size: clamp(1.55rem, 1.2rem + 1.8vw, 2.1rem);
  letter-spacing: -0.02em;
  margin-bottom: 0.6rem;
}

.hero-summary {
  color: var(--text-muted);
  font-size: 0.98rem;
  margin-bottom: 1.35rem;
}

.hero-highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0.85rem;
}

.highlight-item {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-md);
  padding: 0.95rem 1.1rem;
}

.highlight-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 0.25rem;
}

.highlight-desc {
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* Section Card */
.section-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-lg);
  padding: 1.65rem;
  box-shadow: var(--shadow-sm);
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 1.2rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-main);
}

.section-title {
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Grid Layouts */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1rem;
}

.subcard {
  background-color: var(--bg-page);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.2rem;
}

.subcard-title {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-bottom: 0.45rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.subcard-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  font-size: 0.88rem;
}

.subcard-list li {
  position: relative;
  padding-left: 1rem;
}

.subcard-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--indigo-600);
  font-weight: 700;
}

/* Due Date Badges */
.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 0.6rem;
}

.due-badge {
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.2rem 0.55rem;
  border-radius: 6px;
}

.due-done {
  background-color: var(--emerald-50);
  color: var(--emerald-700);
  border: 1px solid var(--emerald-200);
}

.due-soon {
  background-color: var(--amber-50);
  color: var(--amber-700);
  border: 1px solid var(--amber-200);
}

.due-overdue {
  background-color: var(--rose-50);
  color: var(--rose-700);
  border: 1px solid var(--rose-200);
}

.due-normal {
  background-color: var(--bg-subtle);
  color: var(--text-main);
  border: 1px solid var(--border-strong);
}

/* Keyboard Tag */
kbd {
  display: inline-block;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.78rem;
  font-weight: 600;
  line-height: 1.2;
  color: var(--text-strong);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  border-radius: 5px;
  padding: 0.18rem 0.42rem;
  white-space: nowrap;
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.84rem;
  background-color: var(--bg-subtle);
  color: var(--text-strong);
  padding: 0.15rem 0.4rem;
  border-radius: 5px;
}

pre.code-sample {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.82rem;
  background-color: var(--bg-subtle);
  color: var(--text-strong);
  padding: 0.65rem 0.8rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-main);
  overflow-x: auto;
  line-height: 1.5;
}

/* Tables */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border-main);
  border-radius: var(--radius-md);
}

.table-wrap + .table-wrap,
.sub-heading + .table-wrap {
  margin-top: 0.65rem;
}

.sub-heading {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-strong);
  margin-top: 1.25rem;
  margin-bottom: 0.5rem;
}

.sub-heading:first-of-type {
  margin-top: 0;
}

.info-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  text-align: left;
  background-color: var(--bg-surface);
}

.info-table th,
.info-table td {
  padding: 0.7rem 0.95rem;
  border-bottom: 1px solid var(--border-main);
  vertical-align: middle;
}

.info-table th {
  background-color: var(--bg-page);
  color: var(--text-strong);
  font-weight: 700;
  white-space: nowrap;
}

.info-table tr:last-child td {
  border-bottom: none;
}

/* Note Callout Previews */
.note-preview {
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 600;
  border-left: 4px solid;
}

.note-info {
  background-color: var(--emerald-50);
  border-color: var(--emerald-600);
  color: var(--emerald-700);
}

.note-warn {
  background-color: var(--amber-50);
  border-color: #f59e0b;
  color: var(--amber-700);
}

.note-alert {
  background-color: var(--rose-50);
  border-color: #e11d48;
  color: var(--rose-700);
}

/* Step Flow */
.flow-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0.9rem;
}

.flow-step {
  background-color: var(--bg-page);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-md);
  padding: 1rem 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.flow-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: var(--radius-full);
  background-color: var(--indigo-600);
  color: #ffffff;
  font-size: 0.78rem;
  font-weight: 700;
}

/* Policy Sections */
.policy-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
  margin-top: 0.4rem;
}

.policy-block {
  margin-top: 1.4rem;
}

.policy-block h3 {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
  color: var(--text-strong);
}

.policy-block p {
  font-size: 0.92rem;
  margin-bottom: 0.65rem;
}

.policy-block ul {
  margin: 0.4rem 0 0.8rem 1.35rem;
  font-size: 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border-main);
  background-color: var(--bg-surface);
  padding: 1.75rem 1.25rem;
  margin-top: auto;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.65rem;
  text-align: center;
}

.footer-nav {
  display: flex;
  gap: 1.25rem;
  font-size: 0.88rem;
  font-weight: 600;
}

.footer-copy {
  font-size: 0.8rem;
  color: var(--text-muted);
}

@media (max-width: 640px) {
  .header-inner {
    padding: 0.65rem 1rem;
  }

  .brand-tag {
    display: none;
  }

  .main-container {
    padding: 1.25rem 0.9rem 3rem;
    gap: 1.25rem;
  }

  .hero,
  .section-card {
    padding: 1.25rem;
  }
}