/* ============================================================
   GLOBAL STYLES
   ============================================================ */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* --- Reset --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + var(--space-4));
  -webkit-text-size-adjust: 100%;
}
body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-relaxed);
  color: var(--color-text);
  background: var(--color-surface);
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}
img, svg { max-width: 100%; display: block; }
button { cursor: pointer; border: none; background: none; font: inherit; }
a { color: var(--color-link); }

/* --- Layout shell --- */
.site-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
}
.site-main {
  flex: 1;
  width: 100%;
  max-width: var(--max-width-wide);
  margin: 0 auto;
  padding: var(--space-8) var(--space-6);
}
@media (max-width: 768px) {
  .site-main { padding: var(--space-6) var(--space-4); }
}

/* --- Screen-reader only --- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* --- Focus rings (WCAG 2.4.7) --- */
:focus-visible {
  outline: var(--focus-width) solid var(--focus-color);
  outline-offset: var(--focus-offset);
  border-radius: var(--radius-sm);
}

/* ============================================================
   TYPOGRAPHY
   ============================================================ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  color: var(--color-neutral-900);
}
h1 {
  font-size: clamp(var(--text-3xl), 4vw, var(--text-5xl));
  font-weight: var(--weight-extrabold);
  background: linear-gradient(135deg, var(--color-green-700) 0%, var(--color-green-500) 50%, var(--color-teal-500) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-6);
}
h2 {
  font-size: clamp(var(--text-xl), 2.5vw, var(--text-3xl));
  color: var(--color-green-800);
  margin-top: var(--space-12);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-2);
  border-bottom: 2px solid var(--color-green-200);
}
h3 {
  font-size: clamp(var(--text-lg), 2vw, var(--text-2xl));
  color: var(--color-neutral-800);
  margin-top: var(--space-8);
  margin-bottom: var(--space-3);
}
h4 { font-size: var(--text-lg); color: var(--color-neutral-800); margin-top: var(--space-6); margin-bottom: var(--space-2); }
h5, h6 { font-size: var(--text-base); color: var(--color-neutral-700); margin-top: var(--space-4); margin-bottom: var(--space-2); }

p {
  margin-bottom: var(--space-5);
  line-height: var(--leading-relaxed);
}
strong { font-weight: var(--weight-semibold); color: var(--color-neutral-900); }

/* --- Links --- */
a {
  color: var(--color-link);
  text-decoration: underline;
  text-decoration-color: var(--color-green-300);
  text-underline-offset: 3px;
  transition: color var(--transition-fast), text-decoration-color var(--transition-fast);
}
a:hover {
  color: var(--color-link-hover);
  text-decoration-color: var(--color-green-500);
}

/* --- Lists --- */
ul, ol {
  padding-left: var(--space-6);
  margin-bottom: var(--space-5);
}
li {
  margin-bottom: var(--space-2);
  line-height: var(--leading-relaxed);
}
li > ul, li > ol { margin-top: var(--space-2); margin-bottom: 0; }

/* --- Inline code --- */
:not(pre) > code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--color-neutral-100);
  color: inherit;
  border-radius: var(--radius-sm);
  padding: 0.1em 0.3em;
}

/* --- Blockquote --- */
blockquote {
  border-left: 4px solid var(--color-green-400);
  background: var(--color-green-50);
  padding: var(--space-4) var(--space-5);
  margin: var(--space-6) 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--color-neutral-700);
}
blockquote > p:last-child { margin-bottom: 0; }

/* --- Horizontal rule --- */
hr {
  border: none;
  border-top: 2px solid var(--color-neutral-200);
  margin: var(--space-10) 0;
}

/* ============================================================
   MARKDOWN CHECKBOXES
   ============================================================ */
.md-checkbox {
  appearance: none;
  -webkit-appearance: none;
  width: 1.1em;
  height: 1.1em;
  border: 2px solid var(--color-green-500);
  border-radius: var(--radius-sm);
  background: var(--color-white);
  cursor: pointer;
  vertical-align: middle;
  margin-right: var(--space-2);
  flex-shrink: 0;
  transition: background var(--transition-fast), border-color var(--transition-fast);
  position: relative;
}
.md-checkbox:checked {
  background: var(--color-green-500);
  border-color: var(--color-green-600);
}
.md-checkbox:checked::after {
  content: '';
  position: absolute;
  left: 3px;
  top: 0px;
  width: 5px;
  height: 9px;
  border: 2px solid white;
  border-top: none;
  border-left: none;
  transform: rotate(45deg);
}
.md-checkbox-label {
  cursor: pointer;
  vertical-align: middle;
  transition: color var(--transition-fast);
}
.md-checkbox-label.is-checked,
.md-checkbox:checked + .md-checkbox-label {
  text-decoration: line-through;
  color: var(--color-neutral-500);
}
/* Remove bullet from list items containing checkboxes */
li:has(.md-checkbox) {
  list-style: none;
  margin-left: calc(-1 * var(--space-6));
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
  padding-left: 0;
}

/* ============================================================
   TABLES
   ============================================================ */
.table-scroll {
  overflow-x: auto;
  margin: var(--space-6) 0;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
  background: var(--color-white);
}
thead {
  background: linear-gradient(135deg, var(--color-green-800), var(--color-green-700));
  color: var(--color-white);
}
thead th {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  font-weight: var(--weight-semibold);
  font-size: var(--text-sm);
  letter-spacing: 0.03em;
  white-space: nowrap;
  border-bottom: 2px solid var(--color-green-600);
}
tbody tr {
  border-bottom: 1px solid var(--color-border);
  transition: background var(--transition-fast);
}
tbody tr:last-child { border-bottom: none; }
tbody tr:hover { background: var(--color-green-50); }
tbody td {
  padding: var(--space-3) var(--space-4);
  vertical-align: top;
  line-height: var(--leading-relaxed);
}
tbody tr:nth-child(even) { background: var(--color-neutral-50); }
tbody tr:nth-child(even):hover { background: var(--color-green-50); }

/* ============================================================
   CONTENT PAGE LAYOUT
   ============================================================ */
.page-content {
  max-width: var(--max-width-wide);
  margin: 0 auto;
}
.page-content-wide {
  max-width: var(--max-width-wide);
}

/* Anchor link offset helper (header-linked headings) */
[id] {
  scroll-margin-top: calc(var(--header-height) + var(--space-6));
}

/* Direct anchor links inside headings — aria-hidden # symbol only */
.header-anchor {
  color: var(--color-neutral-400);
  text-decoration: none;
  margin-left: var(--space-2);
  opacity: 0;
  transition: opacity var(--transition-fast);
  font-size: 0.8em;
  font-weight: var(--weight-normal);
}
:is(h1, h2, h3, h4):hover .header-anchor,
.header-anchor:focus { opacity: 1; }