/* ==========================================================================
   AI転職ラボ — style.css
   Pure CSS foundation for a Japanese long-form blog.
   Google Fonts (Noto Sans JP / Noto Serif JP) must be loaded in <head>:

   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link rel="stylesheet"
     href="https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;500;700&family=Noto+Serif+JP:wght@700&display=swap">
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. Design tokens
   -------------------------------------------------------------------------- */
:root {
  /* Brand colors */
  --color-primary: #1E3A8A;
  --color-primary-dark: #0F172A;
  --color-accent: #F97316;
  --color-accent-hover: #EA580C;

  /* Surfaces */
  --color-bg: #FFFFFF;
  --color-bg-muted: #F8FAFC;

  /* Text */
  --color-text: #1F2937;
  --color-text-muted: #6B7280;

  /* Links */
  --color-link: #1D4ED8;
  --color-link-visited: #6D28D9;

  /* Callout blocks */
  --color-block-experience-bg: #FEFCE8;
  --color-block-experience-border: #EAB308;
  --color-block-info-bg: #DBEAFE;
  --color-block-info-border: #2563EB;
  --color-block-warning-bg: #FEE2E2;
  --color-block-warning-border: #DC2626;

  /* Borders / dividers */
  --color-border: #E5E7EB;

  /* Typography */
  --font-sans: "Noto Sans JP", "游ゴシック体", "Yu Gothic", "Hiragino Sans",
               "ヒラギノ角ゴ ProN", "メイリオ", Meiryo, sans-serif;
  --font-serif: "Noto Serif JP", "游明朝", "Yu Mincho", "YuMincho",
                "Hiragino Mincho ProN", serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* Body size — overridden for PC further down */
  --fs-body: 16px;

  /* Layout */
  --w-max: 1200px;
  --w-article: 720px;
  --w-sidebar: 300px;
  --gutter: 40px;

  /* Spacing scale (4pt) */
  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 48px;
  --sp-8: 64px;

  /* Radii */
  --r-sm: 4px;
  --r-md: 8px;
  --r-lg: 12px;
  --r-pill: 999px;

  /* Elevation */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 32px rgba(15, 23, 42, 0.12);

  /* Motion */
  --ease: cubic-bezier(0.2, 0.6, 0.2, 1);
  --dur: 180ms;

  /* Sticky header height */
  --h-header: 64px;
}

/* Dark mode scaffolding — intentionally commented; enable by adding
   `data-theme="dark"` to <html> and overriding the tokens below.
   ----------------------------------------------------------------
[data-theme="dark"] {
  --color-bg: #0F172A;
  --color-bg-muted: #111827;
  --color-text: #E5E7EB;
  --color-text-muted: #9CA3AF;
  --color-border: #1F2937;
  --color-link: #60A5FA;
  --color-link-visited: #A78BFA;
}
*/

/* --------------------------------------------------------------------------
   2. Reset
   -------------------------------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  -moz-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--h-header) + 16px);
}

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd,
ul, ol {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

img, picture, svg, video {
  display: block;
  max-width: 100%;
  height: auto;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

button {
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

a {
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
a:visited { color: var(--color-link-visited); }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--r-sm);
}

:where(img, svg) { border-style: none; }

/* --------------------------------------------------------------------------
   3. Base typography
   -------------------------------------------------------------------------- */
body {
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.8;
  color: var(--color-text);
  background: var(--color-bg);
  font-feature-settings: "palt";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* Headings — mobile defaults, PC bumps in the media query */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-primary-dark);
  letter-spacing: 0.01em;
  text-wrap: pretty;
}

h1 { font-size: 26px; line-height: 1.35; }
h2 { font-size: 22px; }
h3 { font-size: 18px; }
h4 { font-size: 16px; }
h5 { font-size: 15px; }
h6 { font-size: 14px; text-transform: none; color: var(--color-text-muted); }

p { text-wrap: pretty; }

p + p,
p + ul,
p + ol,
p + blockquote,
p + h2,
p + h3,
ul + p,
ol + p,
h2 + p,
h3 + p { margin-top: 1em; }

h2 { margin-top: 2.2em; }
h3 { margin-top: 1.8em; }

/* List styling for article body */
.prose ul,
.prose ol { padding-left: 1.5em; margin-top: 1em; }
.prose ul li { list-style: disc; }
.prose ol li { list-style: decimal; }
.prose li + li { margin-top: 0.4em; }

/* Blockquote */
blockquote {
  margin: 1.5em 0;
  padding: var(--sp-4) var(--sp-5);
  border-left: 4px solid var(--color-primary);
  background: var(--color-bg-muted);
  color: var(--color-text);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  font-style: normal;
}
blockquote p + p { margin-top: 0.6em; }
blockquote cite {
  display: block;
  margin-top: var(--sp-2);
  font-size: 0.9em;
  color: var(--color-text-muted);
  font-style: normal;
}

/* Inline & block code */
code, kbd, samp, pre {
  font-family: var(--font-mono);
  font-size: 0.92em;
}
:not(pre) > code {
  background: #F1F5F9;
  color: #0F172A;
  padding: 0.15em 0.4em;
  border-radius: var(--r-sm);
  border: 1px solid var(--color-border);
}
pre {
  margin: 1.2em 0;
  padding: var(--sp-4) var(--sp-5);
  background: #0F172A;
  color: #E5E7EB;
  border-radius: var(--r-md);
  overflow-x: auto;
  line-height: 1.6;
}
pre code { background: transparent; border: 0; padding: 0; color: inherit; }

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.4em 0;
  font-size: 0.95em;
}
th, td {
  padding: var(--sp-3) var(--sp-4);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}
th {
  background: var(--color-bg-muted);
  font-weight: 700;
  color: var(--color-primary-dark);
}
tbody tr:hover { background: #FAFCFF; }

hr {
  border: 0;
  border-top: 1px solid var(--color-border);
  margin: var(--sp-7) 0;
}

/* Within experience blocks, serif H3 (per spec) */
.block-experience h3,
.section-experience h3 {
  font-family: var(--font-serif);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   4. Layout utilities
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--w-max);
  margin-inline: auto;
  padding-inline: var(--sp-4);
}

.wrapper {
  width: 100%;
  max-width: var(--w-article);
  margin-inline: auto;
  padding-inline: var(--sp-4);
}

.stack > * + * { margin-top: var(--sp-4); }
.stack-lg > * + * { margin-top: var(--sp-6); }
.stack-xl > * + * { margin-top: var(--sp-7); }

.grid-2col { display: grid; grid-template-columns: 1fr; gap: var(--sp-5); }
.grid-3col { display: grid; grid-template-columns: 1fr; gap: var(--sp-5); }
.grid-4col { display: grid; grid-template-columns: 1fr; gap: var(--sp-5); }

.row-main {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gutter);
}

.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.gap-2 { gap: var(--sp-2); }
.gap-3 { gap: var(--sp-3); }
.gap-4 { gap: var(--sp-4); }

.text-muted { color: var(--color-text-muted); }
.text-center { text-align: center; }

.section { padding-block: var(--sp-7); }
.section-muted { background: var(--color-bg-muted); }

/* --------------------------------------------------------------------------
   5. Components
   -------------------------------------------------------------------------- */

/* Buttons ----------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: 14px 32px;
  border-radius: var(--r-md);
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  border: 2px solid transparent;
  transition: background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}
.btn-primary:visited { color: #fff; }
.btn-primary:hover {
  background: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.btn-primary:active { transform: translateY(0); }

.btn-outline {
  background: #fff;
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.btn-outline:visited { color: var(--color-primary); }
.btn-outline:hover {
  background: var(--color-primary);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-sm { padding: 8px 16px; font-size: 0.9em; }
.btn-lg { padding: 18px 40px; font-size: 1.05em; }
.btn-block { display: flex; width: 100%; }

/* Tags / pills ------------------------------------------------------------ */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border: 1px solid var(--color-primary);
  color: var(--color-primary);
  background: #fff;
  border-radius: var(--r-pill);
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
  line-height: 1.6;
  letter-spacing: 0.02em;
}
.tag:visited { color: var(--color-primary); }
.tag:hover {
  background: var(--color-primary);
  color: #fff;
  text-decoration: none;
}

.tag-solid {
  background: var(--color-primary);
  color: #fff;
}
.tag-solid:hover { background: var(--color-primary-dark); }

.tag-accent {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.tag-accent:hover { background: var(--color-accent); color: #fff; }

/* Article card ------------------------------------------------------------ */
.card {
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--r-md);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  transition: box-shadow var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
  height: 100%;
}
.card:visited { color: inherit; }
.card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  border-color: #D1D5DB;
  text-decoration: none;
}
.card:hover .card-title { color: var(--color-accent); }

.card-thumb {
  position: relative;
  aspect-ratio: 16 / 9;
  width: 100%;
  background: var(--color-bg-muted);
  overflow: hidden;
}
.card-thumb img,
.card-thumb svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 400ms var(--ease);
}
.card:hover .card-thumb img,
.card:hover .card-thumb svg { transform: scale(1.04); }

.card-body {
  padding: var(--sp-4) var(--sp-5) var(--sp-5);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  flex: 1;
}

.card-title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.55;
  color: var(--color-primary-dark);
  margin: 0;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: color var(--dur) var(--ease);
}

.card-meta {
  margin-top: auto;
  font-size: 13px;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}
.card-meta time { font-variant-numeric: tabular-nums; }

/* Callout blocks ---------------------------------------------------------- */
.block-experience,
.block-info,
.block-warning {
  position: relative;
  margin: 1.6em 0;
  padding: var(--sp-5) var(--sp-5) var(--sp-5) 64px;
  border-radius: var(--r-md);
  border-left: 4px solid;
  font-size: 0.98em;
}

.block-experience::before,
.block-info::before,
.block-warning::before {
  position: absolute;
  left: 20px;
  top: var(--sp-5);
  font-size: 22px;
  line-height: 1;
}

.block-experience {
  background: var(--color-block-experience-bg);
  border-left-color: var(--color-block-experience-border);
}
.block-experience::before { content: "💭"; }
.block-experience h3,
.block-experience h4 {
  font-family: var(--font-serif);
  margin-top: 0;
  color: var(--color-primary-dark);
}

.block-info {
  background: var(--color-block-info-bg);
  border-left-color: var(--color-block-info-border);
}
.block-info::before { content: "ℹ️"; }
.block-info h3,
.block-info h4 { margin-top: 0; color: var(--color-primary-dark); }

.block-warning {
  background: var(--color-block-warning-bg);
  border-left-color: var(--color-block-warning-border);
}
.block-warning::before { content: "⚠️"; }
.block-warning h3,
.block-warning h4 { margin-top: 0; color: var(--color-primary-dark); }

/* Prose column — for article bodies --------------------------------------- */
.prose {
  max-width: var(--w-article);
  margin-inline: auto;
}
.prose > * + * { margin-top: 1em; }
.prose h2 { margin-top: 2.2em; padding-bottom: var(--sp-2); border-bottom: 2px solid var(--color-primary); }
.prose h3 { margin-top: 1.8em; padding-left: var(--sp-3); border-left: 4px solid var(--color-accent); }
.prose img { border-radius: var(--r-md); margin-block: 1.4em; }
.prose figure { margin: 1.6em 0; }
.prose figcaption {
  font-size: 0.88em;
  color: var(--color-text-muted);
  text-align: center;
  margin-top: var(--sp-2);
}

/* --------------------------------------------------------------------------
   6. Site header
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  box-shadow: 0 1px 0 rgba(15, 23, 42, 0.02);
  transition: box-shadow var(--dur) var(--ease);
}
.site-header.is-scrolled {
  box-shadow: 0 4px 16px rgba(15, 23, 42, 0.08);
}

.site-header__inner {
  max-width: var(--w-max);
  margin-inline: auto;
  height: var(--h-header);
  padding-inline: var(--sp-4);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
}

.site-logo {
  display: inline-flex;
  align-items: baseline;
  gap: 2px;
  font-weight: 900;
  font-size: 22px;
  line-height: 1;
  letter-spacing: 0.02em;
  text-decoration: none;
  white-space: nowrap;
}
.site-logo:visited { color: inherit; }
.site-logo__ai { color: var(--color-accent); }
.site-logo__jp { color: var(--color-primary); }
.site-logo__tag {
  display: none;
  margin-left: var(--sp-3);
  padding-left: var(--sp-3);
  border-left: 1px solid var(--color-border);
  font-size: 12px;
  font-weight: 500;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.site-nav {
  display: none;
}
.site-nav ul {
  display: flex;
  align-items: center;
  gap: var(--sp-5);
}
.site-nav a {
  display: inline-flex;
  align-items: center;
  height: var(--h-header);
  padding: 0 2px;
  color: var(--color-primary-dark);
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}
.site-nav a:visited { color: var(--color-primary-dark); }

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--r-pill);
  color: var(--color-primary-dark);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.icon-btn:hover { background: var(--color-bg-muted); color: var(--color-accent); }
.icon-btn svg { width: 20px; height: 20px; }

/* Hamburger --------------------------------------------------------------- */
.hamburger {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  gap: 5px;
  border-radius: var(--r-pill);
  transition: background var(--dur) var(--ease);
}
.hamburger:hover { background: var(--color-bg-muted); }
.hamburger__bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-primary-dark);
  border-radius: 2px;
  transition: transform var(--dur) var(--ease),
              opacity var(--dur) var(--ease);
}
.hamburger[aria-expanded="true"] .hamburger__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.hamburger[aria-expanded="true"] .hamburger__bar:nth-child(2) {
  opacity: 0;
}
.hamburger[aria-expanded="true"] .hamburger__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile drawer ----------------------------------------------------------- */
.mobile-nav {
  position: fixed;
  inset: var(--h-header) 0 0 0;
  z-index: 40;
  background: var(--color-bg);
  transform: translateX(100%);
  transition: transform 260ms var(--ease);
  overflow-y: auto;
  padding: var(--sp-5) var(--sp-4) var(--sp-8);
  visibility: hidden;
}
.mobile-nav.is-open {
  transform: translateX(0);
  visibility: visible;
  box-shadow: -8px 0 24px rgba(15, 23, 42, 0.08);
}
.mobile-nav ul { display: flex; flex-direction: column; }
.mobile-nav li { border-bottom: 1px solid var(--color-border); }
.mobile-nav a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-4) var(--sp-2);
  color: var(--color-primary-dark);
  font-size: 16px;
  font-weight: 500;
  text-decoration: none;
}
.mobile-nav a:visited { color: var(--color-primary-dark); }
.mobile-nav a:hover,
.mobile-nav a[aria-current="page"] { color: var(--color-accent); }
.mobile-nav a::after {
  content: "›";
  color: var(--color-text-muted);
  font-size: 20px;
  line-height: 1;
}
.mobile-nav__cta {
  margin-top: var(--sp-6);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--color-border);
}

.body-lock { overflow: hidden; }

/* --------------------------------------------------------------------------
   7. Site footer
   -------------------------------------------------------------------------- */
.site-footer {
  background: var(--color-bg-muted);
  border-top: 1px solid var(--color-border);
  color: var(--color-text);
  margin-top: var(--sp-8);
}

.site-footer__top {
  max-width: var(--w-max);
  margin-inline: auto;
  padding: var(--sp-7) var(--sp-4);
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-6);
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--sp-3);
}
.footer-col ul { display: flex; flex-direction: column; gap: var(--sp-2); }
.footer-col a {
  color: var(--color-text);
  font-size: 14px;
  text-decoration: none;
}
.footer-col a:visited { color: var(--color-text); }
.footer-col a:hover { color: var(--color-accent); text-decoration: underline; }

.footer-about p {
  margin-top: var(--sp-3);
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.8;
  max-width: 420px;
}

.footer-social {
  display: flex;
  gap: var(--sp-2);
  margin-top: var(--sp-4);
}
.footer-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--r-pill);
  border: 1px solid var(--color-border);
  background: #fff;
  color: var(--color-primary);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.footer-social a:hover {
  background: var(--color-primary);
  color: #fff;
}
.footer-social svg { width: 16px; height: 16px; }

.site-footer__bottom {
  border-top: 1px solid var(--color-border);
  padding: var(--sp-4);
}
.site-footer__bottom-inner {
  max-width: var(--w-max);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
  font-size: 12px;
  color: var(--color-text-muted);
}

/* --------------------------------------------------------------------------
   8. Floating CTA (mobile)
   -------------------------------------------------------------------------- */
.floating-cta {
  position: fixed;
  left: var(--sp-3);
  right: var(--sp-3);
  bottom: calc(var(--sp-3) + env(safe-area-inset-bottom, 0));
  z-index: 30;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--sp-3) var(--sp-4);
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  transform: translateY(calc(100% + var(--sp-6)));
  opacity: 0;
  pointer-events: none;
  transition: transform 320ms var(--ease), opacity 260ms var(--ease);
}
.floating-cta.is-visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}
.floating-cta__text {
  flex: 1;
  min-width: 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--color-text);
}
.floating-cta__text strong {
  display: block;
  color: var(--color-primary-dark);
  font-size: 14px;
  margin-bottom: 2px;
}
.floating-cta__btn {
  flex-shrink: 0;
  padding: 10px 18px;
  font-size: 13px;
  border-radius: var(--r-md);
  background: var(--color-accent);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--dur) var(--ease);
}
.floating-cta__btn:visited { color: #fff; }
.floating-cta__btn:hover { background: var(--color-accent-hover); }
.floating-cta__close {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--r-pill);
  color: var(--color-text-muted);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.floating-cta__close:hover { background: var(--color-bg-muted); color: var(--color-primary-dark); }
.floating-cta__close svg { width: 16px; height: 16px; }

/* --------------------------------------------------------------------------
   9. Accessibility utilities
   -------------------------------------------------------------------------- */
.visually-hidden,
.sr-only {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: var(--sp-3);
  padding: var(--sp-3) var(--sp-4);
  background: var(--color-primary);
  color: #fff;
  border-radius: var(--r-md);
  text-decoration: none;
  z-index: 100;
  transition: top var(--dur) var(--ease);
}
.skip-link:focus { top: var(--sp-3); outline: 2px solid var(--color-accent); outline-offset: 2px; }

@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;
  }
}

/* --------------------------------------------------------------------------
   10. Responsive — PC (min-width: 1024px)
   -------------------------------------------------------------------------- */
@media (min-width: 1024px) {
  :root {
    --fs-body: 18px;
  }

  h1 { font-size: 32px; }
  h2 { font-size: 26px; }
  h3 { font-size: 20px; }
  h4 { font-size: 18px; }

  .container,
  .wrapper {
    padding-inline: var(--sp-5);
  }

  .row-main {
    grid-template-columns: minmax(0, 1fr) var(--w-sidebar);
    gap: var(--gutter);
  }

  .grid-2col { grid-template-columns: repeat(2, 1fr); gap: var(--sp-6); }
  .grid-3col { grid-template-columns: repeat(3, 1fr); gap: var(--sp-6); }
  .grid-4col { grid-template-columns: repeat(4, 1fr); gap: var(--sp-5); }

  .site-logo { font-size: 24px; }
  .site-logo__tag { display: inline-block; }
  .site-nav { display: block; }
  .hamburger { display: none; }
  .mobile-nav { display: none; }

  .site-footer__top {
    grid-template-columns: 2fr 1fr 1fr;
    gap: var(--gutter);
    padding-block: var(--sp-8);
  }
  .site-footer__bottom-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

  /* Floating CTA is mobile-only per spec */
  .floating-cta { display: none; }

  .section { padding-block: var(--sp-8); }
}

/* Wider screens — keep logo compact */
@media (min-width: 1280px) {
  .site-nav ul { gap: var(--sp-6); }
  .site-nav a { font-size: 15px; }
}
