:root {
  --color-primary: #2B3A67;
  --color-secondary: #1F7A8C;
  --color-accent: #F4D35E;
  --color-background: #F7F7FB;
  --color-surface: #FFFFFF;
  --color-text: #111827;
  --color-text-muted: #4B5563;
  --color-border: #D6D9E6;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(17, 24, 39, 0.10);
  --maxw: 1120px;
  --spacing-unit: 1.5rem;
}

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

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.75;
  color: var(--color-text);
  background-color: var(--color-background);
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body > * {
  display: grid;
  grid-template-columns: 1fr;
  grid-template-areas:
    "header"
    "main"
    "aside"
    "footer";
  min-height: 100vh;
}

header {
  grid-area: header;
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: calc(var(--spacing-unit) * 1.5) var(--spacing-unit);
  box-shadow: var(--shadow);
}

header .header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-unit);
}

header .site-name {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-primary);
  text-decoration: none;
  line-height: 1.2;
}

header .site-name:hover {
  color: var(--color-secondary);
  transition: color 0.2s ease;
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--spacing-unit) * 0.75);
}

nav a {
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: calc(var(--radius) * 0.5);
  transition: background-color 0.2s ease, color 0.2s ease;
  display: block;
}

nav a:hover {
  background-color: var(--color-background);
  color: var(--color-primary);
}

nav a:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

main {
  grid-area: main;
  max-width: var(--maxw);
  width: 100%;
  margin: 0 auto;
  padding: calc(var(--spacing-unit) * 2) var(--spacing-unit);
}

aside {
  grid-area: aside;
  max-width: var(--maxw);
  width: 100%;
  margin: 0 auto;
  padding: 0 var(--spacing-unit) calc(var(--spacing-unit) * 2);
}

footer {
  grid-area: footer;
  background-color: var(--color-primary);
  color: var(--color-surface);
  padding: calc(var(--spacing-unit) * 1.5) var(--spacing-unit);
  margin-top: auto;
  text-align: center;
  font-size: 0.875rem;
  line-height: 1.6;
}

footer a {
  color: var(--color-accent);
  text-decoration: none;
  transition: opacity 0.2s ease;
}

footer a:hover {
  opacity: 0.8;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-primary);
  margin-bottom: var(--spacing-unit);
}

h1 {
  font-size: 2rem;
  margin-top: 0;
  margin-bottom: calc(var(--spacing-unit) * 1.5);
}

h2 {
  font-size: 1.75rem;
  margin-top: calc(var(--spacing-unit) * 2);
}

h3 {
  font-size: 1.375rem;
  margin-top: calc(var(--spacing-unit) * 1.5);
}

h4 {
  font-size: 1.125rem;
  margin-top: var(--spacing-unit);
}

p {
  margin-bottom: var(--spacing-unit);
}

a {
  color: var(--color-secondary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-primary);
}

a:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

article, section {
  margin-bottom: calc(var(--spacing-unit) * 2);
}

section {
  background-color: var(--color-surface);
  padding: calc(var(--spacing-unit) * 1.5);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: calc(var(--spacing-unit) * 1.5);
}

blockquote {
  border-left: 4px solid var(--color-accent);
  padding: var(--spacing-unit);
  margin: var(--spacing-unit) 0;
  background-color: var(--color-background);
  font-style: italic;
  color: var(--color-text-muted);
  border-radius: calc(var(--radius) * 0.5);
}

blockquote p:last-child {
  margin-bottom: 0;
}

aside {
  background-color: var(--color-surface);
  padding: var(--spacing-unit);
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  margin-bottom: var(--spacing-unit);
}

aside h3, aside h4 {
  font-size: 1.125rem;
  margin-top: 0;
}

.breadcrumbs {
  font-size: 0.875rem;
  margin-bottom: var(--spacing-unit);
  color: var(--color-text-muted);
}

.breadcrumbs ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
}

.breadcrumbs li:not(:last-child)::after {
  content: "›";
  margin-left: 0.5rem;
  color: var(--color-text-muted);
}

.breadcrumbs a {
  color: var(--color-secondary);
  text-decoration: none;
}

.breadcrumbs a:hover {
  text-decoration: underline;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--spacing-unit) 0;
  background-color: var(--color-surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  font-size: 0.9375rem;
}

table caption {
  font-weight: 700;
  text-align: left;
  padding: var(--spacing-unit);
  background-color: var(--color-primary);
  color: var(--color-surface);
  font-size: 1rem;
  letter-spacing: -0.01em;
}

thead {
  background-color: var(--color-background);
}

th {
  text-align: left;
  padding: 1rem;
  font-weight: 600;
  color: var(--color-primary);
  border-bottom: 2px solid var(--color-border);
}

td {
  padding: 1rem;
  border-bottom: 1px solid var(--color-border);
}

tbody tr:nth-child(even) {
  background-color: var(--color-background);
}

tbody tr {
  transition: background-color 0.2s ease;
}

tbody tr:hover {
  background-color: rgba(31, 122, 140, 0.05);
}

.table-wrapper {
  overflow-x: auto;
  margin: var(--spacing-unit) 0;
  border-radius: var(--radius);
}

details {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--spacing-unit);
  margin-bottom: var(--spacing-unit);
  transition: box-shadow 0.2s ease;
}

details[open] {
  box-shadow: var(--shadow);
}

summary {
  font-weight: 600;
  cursor: pointer;
  color: var(--color-primary);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0;
  transition: color 0.2s ease;
}

summary::-webkit-details-marker {
  display: none;
}

summary::before {
  content: "▸";
  display: inline-block;
  transition: transform 0.2s ease;
  font-size: 1.125rem;
  color: var(--color-secondary);
}

details[open] summary::before {
  transform: rotate(90deg);
}

summary:hover {
  color: var(--color-secondary);
}

summary:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: calc(var(--radius) * 0.5);
}

details[open] summary {
  margin-bottom: var(--spacing-unit);
  padding-bottom: var(--spacing-unit);
  border-bottom: 1px solid var(--color-border);
}

ul, ol {
  margin-bottom: var(--spacing-unit);
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
}

strong {
  font-weight: 600;
  color: var(--color-primary);
}

em {
  font-style: italic;
}

code {
  font-family: "Courier New", Courier, monospace;
  background-color: var(--color-background);
  padding: 0.125rem 0.375rem;
  border-radius: calc(var(--radius) * 0.25);
  font-size: 0.875em;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
}

@media (min-width: 768px) {
  html {
    font-size: 106.25%;
  }

  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 2rem;
  }

  h3 {
    font-size: 1.5rem;
  }

  header .header-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

  nav ul {
    gap: var(--spacing-unit);
  }

  body > * {
    grid-template-columns: 1fr minmax(auto, var(--maxw)) 1fr;
    grid-template-areas:
      "header header header"
      ". main aside"
      "footer footer footer";
  }

  main {
    padding-right: calc(var(--spacing-unit) * 1.5);
  }

  aside {
    max-width: 320px;
    padding: calc(var(--spacing-unit) * 2) var(--spacing-unit) calc(var(--spacing-unit) * 2) 0;
  }

  thead th {
    position: sticky;
    top: 0;
    background-color: var(--color-background);
    z-index: 10;
  }
}

@media (min-width: 1024px) {
  html {
    font-size: 112.5%;
  }

  h1 {
    font-size: 3rem;
  }

  h2 {
    font-size: 2.25rem;
  }

  h3 {
    font-size: 1.75rem;
  }

  body > * {
    grid-template-columns: 1fr minmax(auto, 760px) minmax(auto, 320px) 1fr;
    grid-template-areas:
      "header header header header"
      ". main aside ."
      "footer footer footer footer";
  }

  main {
    padding-right: calc(var(--spacing-unit) * 2);
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  html {
    scroll-behavior: auto;
  }

  summary::before {
    transition: none;
  }
}

@media print {
  body {
    background-color: white;
    color: black;
    font-size: 12pt;
    line-height: 1.5;
  }

  header, footer, nav, aside {
    display: none;
  }

  main {
    max-width: 100%;
    padding: 0;
  }

  a {
    color: black;
    text-decoration: underline;
  }

  a[href^="http"]::after {
    content: " (" attr(href) ")";
    font-size: 0.875em;
  }

  section {
    box-shadow: none;
    border: 1px solid #ccc;
    page-break-inside: avoid;
  }

  h1, h2, h3 {
    page-break-after: avoid;
    color: black;
  }

  table {
    page-break-inside: avoid;
    box-shadow: none;
  }

  thead {
    display: table-header-group;
  }
}

button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

::selection {
  background-color: var(--color-accent);
  color: var(--color-text);
}

:focus {
  outline: none;
}

:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}