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

:root {
  --color-primary: #2563eb;
  --color-secondary: #1d4ed8;
  --color-accent: #bfdbfe;
  --color-bg: #ffffff;
  --color-surface: #eff6ff;
  --color-text: #172554;
  --color-text-muted: #6080b0;
  --color-border: #c8daf0;
  --font-main: 'Georgia', 'Times New Roman', 'Palatino', serif;
  --max-width: 1100px;
  --radius: 20px;
}

body {
  font-family: var(--font-main);
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  background-image: radial-gradient(circle, var(--color-surface) 1px, transparent 1px);
  background-size: 20px 20px;
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr auto;
}

h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--color-text);
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 1.5rem;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: 2rem;
  margin-top: 2rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px dashed var(--color-border);
}

h3 {
  font-size: 1.6rem;
  margin-top: 1.5rem;
}

h4 {
  font-size: 1.3rem;
  margin-top: 1.25rem;
}

h5 {
  font-size: 1.1rem;
  margin-top: 1rem;
}

h6 {
  font-size: 1rem;
  margin-top: 1rem;
  color: var(--color-text-muted);
}

p {
  margin-bottom: 1.25rem;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  border-bottom: 2px dotted var(--color-primary);
  transition: color 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
  padding: 0 2px;
}

a:hover {
  color: var(--color-secondary);
  border-bottom-style: solid;
  background-color: var(--color-accent);
  border-radius: 4px;
}

a:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: 6px;
}

strong {
  font-weight: 700;
  color: var(--color-text);
}

em {
  font-style: italic;
  color: var(--color-text-muted);
}

blockquote {
  margin: 2rem 0;
  padding: 1.5rem 2rem;
  background: linear-gradient(to right, var(--color-surface) 0%, var(--color-bg) 100%);
  border-left: 6px solid var(--color-primary);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-style: italic;
  color: var(--color-text-muted);
  position: relative;
}

blockquote::before {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background-image: radial-gradient(circle, var(--color-accent) 1px, transparent 1px);
  background-size: 15px 15px;
  opacity: 0.3;
  border-radius: 0 var(--radius) var(--radius) 0;
  pointer-events: none;
}

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

.site-header {
  background: linear-gradient(135deg, var(--color-surface) 0%, var(--color-bg) 100%);
  border-bottom: 4px dotted var(--color-border);
  padding: 2rem 1.5rem;
  position: relative;
}

.site-header::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(to right, var(--color-primary), var(--color-secondary), var(--color-primary));
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  align-items: center;
  justify-content: center;
  margin-top: 1.5rem;
}

.site-nav a {
  border: 2px dotted var(--color-border);
  padding: 0.6rem 1.4rem;
  border-radius: var(--radius);
  font-weight: 600;
  transition: all 0.2s ease;
  background-color: var(--color-bg);
}

.site-nav a:hover {
  background-color: var(--color-primary);
  color: var(--color-bg);
  border-style: solid;
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.site-main {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

.site-footer {
  background: linear-gradient(to top, var(--color-surface) 0%, var(--color-bg) 100%);
  border-top: 3px dashed var(--color-border);
  padding: 2.5rem 1.5rem;
  text-align: center;
  color: var(--color-text-muted);
  margin-top: 4rem;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 2rem;
  padding: 1rem;
  background-color: var(--color-surface);
  border-radius: var(--radius);
  border: 2px dotted var(--color-border);
  font-size: 0.9rem;
}

.breadcrumbs a {
  border-bottom: none;
  padding: 0.25rem 0.5rem;
  border-radius: 8px;
}

.breadcrumbs a::after {
  content: '›';
  margin-left: 0.75rem;
  color: var(--color-text-muted);
  font-weight: bold;
}

.breadcrumbs a:last-child::after {
  content: '';
}

.card {
  background: linear-gradient(135deg, var(--color-bg) 0%, var(--color-surface) 100%);
  border: 3px dotted var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  margin-bottom: 2rem;
  transition: box-shadow 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: radial-gradient(circle, var(--color-accent) 1.5px, transparent 1.5px);
  background-size: 25px 25px;
  opacity: 0.2;
  pointer-events: none;
}

.card:hover {
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.15);
  border-color: var(--color-primary);
  border-style: solid;
  transform: translateY(-4px);
}

table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: 2rem 0;
  border: 3px dotted var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--color-bg);
}

thead {
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  color: var(--color-bg);
}

th {
  padding: 1rem;
  text-align: left;
  font-weight: 700;
  border-bottom: 2px solid var(--color-secondary);
}

td {
  padding: 1rem;
  border-bottom: 2px dotted var(--color-border);
}

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

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

tbody tr:hover {
  background-color: var(--color-accent);
}

tbody tr:last-child td {
  border-bottom: none;
}

details {
  margin: 1.5rem 0;
  border: 3px dotted var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  background-color: var(--color-bg);
  transition: border-color 0.2s ease;
}

details[open] {
  border-color: var(--color-primary);
  border-style: solid;
}

summary {
  padding: 1.25rem 1.5rem;
  cursor: pointer;
  background: linear-gradient(to right, var(--color-surface), var(--color-bg));
  font-weight: 600;
  color: var(--color-primary);
  transition: background-color 0.2s ease, color 0.2s ease;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

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

summary::before {
  content: '▶';
  display: inline-block;
  transition: transform 0.2s ease;
  font-size: 0.8rem;
}

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

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

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

details div {
  padding: 1.5rem;
  border-top: 2px dashed var(--color-border);
  animation: slideDown 0.2s ease;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

button,
input[type="submit"],
input[type="button"] {
  font-family: var(--font-main);
  font-size: 1rem;
  padding: 0.75rem 1.75rem;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  color: var(--color-bg);
  border: 3px solid var(--color-primary);
  border-radius: var(--radius);
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s ease;
}

button:hover,
input[type="submit"]:hover,
input[type="button"]:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
  border-style: dotted;
}

button:focus-visible,
input[type="submit"]:focus-visible,
input[type="button"]:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
}

input[type="text"],
input[type="email"],
input[type="search"],
input[type="url"],
textarea {
  font-family: var(--font-main);
  font-size: 1rem;
  padding: 0.75rem 1rem;
  border: 3px dotted var(--color-border);
  border-radius: var(--radius);
  background-color: var(--color-bg);
  color: var(--color-text);
  width: 100%;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="search"]:focus,
input[type="url"]:focus,
textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  border-style: solid;
  box-shadow: 0 0 0 3px var(--color-accent);
}

ul, ol {
  margin: 1.5rem 0;
  padding-left: 2.5rem;
}

li {
  margin-bottom: 0.75rem;
  line-height: 1.7;
}

ul li {
  list-style-type: none;
  position: relative;
}

ul li::before {
  content: '●';
  color: var(--color-primary);
  position: absolute;
  left: -1.5rem;
  font-size: 1.2rem;
}

ol li {
  padding-left: 0.5rem;
}

hr {
  border: none;
  border-top: 3px dashed var(--color-border);
  margin: 3rem 0;
  position: relative;
}

hr::after {
  content: '◆';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--color-bg);
  color: var(--color-primary);
  padding: 0 1rem;
  font-size: 1.2rem;
}

code {
  font-family: 'Courier New', Courier, monospace;
  background-color: var(--color-surface);
  color: var(--color-secondary);
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  border: 2px dotted var(--color-border);
  font-size: 0.9em;
}

pre {
  background-color: var(--color-surface);
  border: 3px dotted var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  overflow-x: auto;
  margin: 2rem 0;
}

pre code {
  background: none;
  border: none;
  padding: 0;
  display: block;
}

@media (min-width: 768px) {
  body {
    font-size: 19px;
  }

  h1 {
    font-size: 3rem;
  }

  h2 {
    font-size: 2.25rem;
  }

  h3 {
    font-size: 1.75rem;
  }

  .site-header {
    padding: 2.5rem 2rem;
  }

  .site-nav {
    justify-content: flex-start;
    gap: 2rem;
  }

  .site-main {
    padding: 4rem 2rem;
  }

  .site-footer {
    padding: 3rem 2rem;
  }

  .card {
    padding: 2.5rem;
  }

  blockquote {
    padding: 2rem 2.5rem;
    margin: 2.5rem 0;
  }
}

@media (min-width: 1024px) {
  body {
    font-size: 20px;
  }

  h1 {
    font-size: 3.5rem;
  }

  h2 {
    font-size: 2.5rem;
  }

  .site-header {
    padding: 3rem 2.5rem;
  }

  .site-main {
    padding: 5rem 2.5rem;
  }

  .site-nav {
    gap: 2.5rem;
  }

  table th,
  table td {
    padding: 1.25rem;
  }
}

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

  details div {
    animation: none;
  }
}

@media print {
  body {
    background: white;
    background-image: none;
  }

  .site-nav,
  .breadcrumbs {
    display: none;
  }

  .site-header,
  .site-footer {
    border: none;
    background: none;
  }

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

  .card {
    border: 1px solid #ccc;
    page-break-inside: avoid;
  }

  a {
    color: #000;
    text-decoration: underline;
  }

  details {
    border: 1px solid #ccc;
  }

  details[open] summary ~ * {
    display: block;
  }
}