/* CSS Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-primary: #2A2F4F;
  --color-secondary: #6B4E71;
  --color-accent: #FF5C7A;
  --color-background: #FBFAF8;
  --color-surface: #FFFFFF;
  --color-text: #14151A;
  --color-text-muted: #4B4F5C;
  --color-border: #D7D2CC;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(20, 21, 26, 0.10);
  --maxw: 1120px;
  --space: 1rem;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-background);
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr auto;
  grid-template-columns: 100%;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 0.75em;
  color: var(--color-primary);
}

h1 {
  font-size: clamp(1.875rem, 1.5rem + 1.5vw, 2.75rem);
  margin-bottom: 1rem;
}

h2 {
  font-size: clamp(1.5rem, 1.25rem + 1vw, 2.25rem);
  margin-top: 2rem;
}

h3 {
  font-size: clamp(1.25rem, 1.125rem + 0.5vw, 1.75rem);
  margin-top: 1.5rem;
}

p {
  margin-bottom: 1em;
}

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

a:hover {
  color: var(--color-accent);
  text-decoration-color: var(--color-accent);
}

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

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

/* Header */
header {
  background-color: var(--color-surface);
  border-bottom: 2px solid var(--color-border);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}

header .header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: var(--space) calc(var(--space) * 1.5);
  display: flex;
  flex-direction: column;
  gap: var(--space);
}

header .site-name {
  font-size: clamp(1.25rem, 1.125rem + 0.5vw, 1.5rem);
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
}

header .site-name:hover {
  color: var(--color-accent);
}

nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--space) * 1.5);
}

nav a {
  font-weight: 500;
  text-decoration: none;
  padding: 0.25rem 0;
  border-bottom: 2px solid transparent;
  transition: border-color 0.2s ease, color 0.2s ease;
}

nav a:hover {
  border-bottom-color: var(--color-accent);
}

nav a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 4px;
}

/* Main Content */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: calc(var(--space) * 2) calc(var(--space) * 1.5);
  width: 100%;
}

article, section {
  background-color: var(--color-surface);
  padding: calc(var(--space) * 2);
  margin-bottom: calc(var(--space) * 2);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

aside {
  background-color: var(--color-background);
  border-left: 4px solid var(--color-accent);
  padding: calc(var(--space) * 1.5);
  margin: calc(var(--space) * 1.5) 0;
  border-radius: var(--radius);
}

/* Blockquotes */
blockquote {
  background-color: rgba(255, 92, 122, 0.05);
  border-left: 5px solid var(--color-accent);
  padding: calc(var(--space) * 1.5);
  margin: calc(var(--space) * 1.5) 0;
  font-style: italic;
  color: var(--color-text-muted);
  border-radius: 0 var(--radius) var(--radius) 0;
}

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

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: calc(var(--space) * 1.5) 0;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
}

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

th {
  padding: calc(var(--space) * 0.75) var(--space);
  text-align: left;
  font-weight: 600;
  position: sticky;
  top: 0;
}

td {
  padding: calc(var(--space) * 0.75) var(--space);
  border-top: 1px solid var(--color-border);
}

tbody tr:nth-child(even) {
  background-color: rgba(42, 47, 79, 0.03);
}

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

tbody tr:hover {
  background-color: rgba(255, 92, 122, 0.08);
}

/* Details/Summary Accordion */
details {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space);
  margin-bottom: var(--space);
  transition: box-shadow 0.3s ease;
}

details:hover {
  box-shadow: var(--shadow);
}

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

summary {
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  padding: calc(var(--space) * 0.5);
  margin: calc(var(--space) * -0.5);
  border-radius: calc(var(--radius) - 2px);
  list-style: none;
  display: flex;
  align-items: center;
  transition: background-color 0.2s ease, color 0.2s ease;
}

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

summary::before {
  content: '▶';
  display: inline-block;
  margin-right: 0.5em;
  transition: transform 0.3s ease;
  color: var(--color-accent);
}

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

summary:hover {
  background-color: rgba(42, 47, 79, 0.05);
  color: var(--color-accent);
}

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

details > *:not(summary) {
  margin-top: var(--space);
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: calc(var(--space) * 1.5);
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.breadcrumbs a {
  color: var(--color-secondary);
}

.breadcrumbs span {
  color: var(--color-text-muted);
}

/* Footer */
footer {
  background-color: var(--color-primary);
  color: var(--color-surface);
  padding: calc(var(--space) * 2) calc(var(--space) * 1.5);
  margin-top: calc(var(--space) * 3);
  text-align: center;
}

footer a {
  color: var(--color-surface);
  text-decoration-color: rgba(255, 255, 255, 0.5);
}

footer a:hover {
  color: var(--color-accent);
  text-decoration-color: var(--color-accent);
}

/* Responsive Breakpoints */
@media (min-width: 768px) {
  header .header-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

  nav ul {
    gap: calc(var(--space) * 2);
  }

  main {
    padding: calc(var(--space) * 3) calc(var(--space) * 2);
  }

  article, section {
    padding: calc(var(--space) * 2.5);
  }

  table {
    font-size: 1rem;
  }

  thead th {
    position: sticky;
    top: 0;
  }
}

@media (min-width: 1024px) {
  main {
    padding: calc(var(--space) * 4) calc(var(--space) * 2);
  }

  article, section {
    padding: calc(var(--space) * 3);
  }

  aside {
    margin: calc(var(--space) * 2) calc(var(--space) * 3);
  }
}

/* Accessibility: Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    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;
  }
}

/* Focus Visible Enhancement */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* Print Styles */
@media print {
  body {
    background-color: white;
    color: black;
  }

  header, footer {
    background-color: white;
    color: black;
    border: 1px solid black;
  }

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

  a[href^="http"]::after {
    content: " (" attr(href) ")";
    font-size: 0.8em;
  }

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

  details {
    border: 1px solid #ccc;
  }

  summary::before {
    content: '';
  }

  details[open] summary::before {
    content: '';
  }

  nav, .breadcrumbs {
    display: none;
  }
}