/* =============================================================================
   ShopFloorWeekly — Main Stylesheet
   Industrial design: dark header, bold sans-serif, high contrast, precision grid
   Mobile-first. Custom properties. No framework.
   ============================================================================= */

/* --- Custom Properties ---------------------------------------------------- */
:root {
  /* Core palette */
  --color-bg:           #F2F0EB;
  --color-bg-alt:       #E8E5DF;
  --color-bg-dark:      #0C1A2E;
  --color-bg-code:      #E2DFD8;
  --color-text:         #18181F;
  --color-text-muted:   #52504A;
  --color-text-light:   #87837A;

  /* Brand */
  --color-blue:         #1B3055;
  --color-blue-light:   #244272;
  --color-blue-xlight:  #3D6496;
  --color-teal:         #0B8C8D;
  --color-teal-light:   #10A8A9;
  --color-teal-xlight:  #C6EAEA;

  /* Industrial accent */
  --color-accent:       #C96610;
  --color-accent-light: #E07E30;
  --color-accent-bg:    #FDF0E4;

  /* Structure */
  --color-border:       #CBC7C0;
  --color-border-light: #E2DFD8;
  --color-white:        #FFFFFF;

  /* Semantic */
  --color-error:        #B91C1C;
  --color-success:      #166534;
  --color-warning:      #92400E;
  --color-warning-bg:   #FFFBEB;

  /* Typography — ALL SANS-SERIF */
  --font-sans:  system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-serif: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif; /* same — kept for compat */
  --font-mono:  'Consolas', 'Monaco', 'Courier New', monospace;

  /* Type scale */
  --text-xs:   0.688rem;
  --text-sm:   0.8125rem;
  --text-base: 1rem;
  --text-md:   1.125rem;
  --text-lg:   1.375rem;
  --text-xl:   1.75rem;
  --text-2xl:  2.25rem;
  --text-3xl:  3rem;

  /* Line heights */
  --leading-tight:  1.15;
  --leading-snug:   1.28;
  --leading-base:   1.65;
  --leading-loose:  1.8;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --max-width-content: 740px;
  --max-width-wide:    1100px;
  --max-width-full:    1280px;

  /* Radius — sharp-but-not-hard for industrial feel */
  --radius-sm:  2px;
  --radius:     4px;
  --radius-md:  6px;
  --radius-lg:  10px;

  /* Shadows — directional, depth-driven */
  --shadow-sm: 0 1px 3px rgba(12,26,46,0.1), 0 1px 2px rgba(12,26,46,0.06);
  --shadow-md: 0 4px 16px rgba(12,26,46,0.13), 0 2px 5px rgba(12,26,46,0.08);
  --shadow-lg: 0 12px 40px rgba(12,26,46,0.18), 0 4px 10px rgba(12,26,46,0.1);

  /* Transitions */
  --transition: 0.15s ease;
}

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

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

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-base);
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

img, video, svg { max-width: 100%; height: auto; display: block; }
a { color: var(--color-blue); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--color-teal); }
a:focus-visible { outline: 2px solid var(--color-teal); outline-offset: 2px; border-radius: var(--radius-sm); }

ul, ol { padding-left: var(--space-6); }
li { margin-bottom: var(--space-2); }

/* --- Skip Link ------------------------------------------------------------ */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  background: var(--color-accent);
  color: var(--color-white);
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: 700;
  border-radius: 0 0 var(--radius) var(--radius);
  z-index: 9999;
  text-decoration: none;
  transition: top var(--transition);
  letter-spacing: 0.03em;
}
.skip-link:focus { top: 0; }

/* --- Layout Containers ---------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width-full);
  margin: 0 auto;
  padding: 0 var(--space-5);
}
@media (min-width: 48em) { .container { padding: 0 var(--space-8); } }
@media (min-width: 80em) { .container { padding: 0 var(--space-12); } }

.content-container {
  max-width: var(--max-width-content);
  margin: 0 auto;
}

.wide-container {
  max-width: var(--max-width-wide);
  margin: 0 auto;
}

/* --- Header --------------------------------------------------------------- */
.site-header {
  background: var(--color-bg-dark);
  border-bottom: 2px solid var(--color-teal);
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
  gap: var(--space-4);
}

/* Logo — override inline style color for dark header */
.site-logo {
  font-family: var(--font-sans);
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--color-blue);   /* default (footer) */
  text-decoration: none;
  letter-spacing: -0.03em;
  white-space: nowrap;
  flex-shrink: 0;
}
.site-header .site-logo {
  color: var(--color-white);
}
.site-header .site-logo:hover {
  color: var(--color-teal-light);
}

/* "Ops" in a slightly lighter shade for visual punch */
.site-header .site-logo .logo-ops { color: var(--color-teal-light); }

.main-nav { display: none; }
.main-nav ul { list-style: none; padding: 0; margin: 0; display: flex; gap: 0; }
.main-nav a {
  display: block;
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: rgba(255,255,255,0.65);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius);
  transition: color var(--transition), background var(--transition);
}
.main-nav a:hover {
  color: var(--color-white);
  background: rgba(255,255,255,0.08);
}
.main-nav a[aria-current="page"] {
  color: var(--color-teal-light);
  background: rgba(11,140,141,0.1);
}

@media (min-width: 60em) { .main-nav { display: block; } }

.nav-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.25rem;
  height: 2.25rem;
  background: none;
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius);
  cursor: pointer;
  padding: 0.4rem 0.5rem;
  flex-shrink: 0;
}
.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: rgba(255,255,255,0.8);
  border-radius: 1px;
  transition: transform var(--transition), opacity var(--transition);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
@media (min-width: 60em) { .nav-toggle { display: none; } }

/* Mobile nav — fixed below sticky header */
.mobile-nav {
  display: none;
  position: fixed;
  top: calc(4rem + 2px); /* header height + teal border */
  left: 0;
  right: 0;
  z-index: 99;
  background: var(--color-bg-dark);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  max-height: calc(100vh - 4rem);
  overflow-y: auto;
  padding: var(--space-4) var(--space-5) var(--space-6);
  box-shadow: 0 8px 32px rgba(0,0,0,0.4);
}
.mobile-nav.is-open { display: block; }
.mobile-nav ul { list-style: none; padding: 0; margin: 0; }
.mobile-nav li { border-bottom: 1px solid rgba(255,255,255,0.07); }
.mobile-nav a {
  display: block;
  padding: var(--space-3) 0;
  font-size: var(--text-base);
  font-weight: 600;
  color: rgba(255,255,255,0.75);
  text-decoration: none;
  letter-spacing: 0.01em;
}
.mobile-nav a:hover { color: var(--color-white); }

/* --- Footer --------------------------------------------------------------- */
.site-footer {
  background: var(--color-bg-dark);
  border-top: 3px solid var(--color-teal);
  color: rgba(255,255,255,0.8);
  padding: var(--space-16) 0 var(--space-8);
  margin-top: var(--space-20);
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 48px 48px;
}

.footer-grid {
  display: grid;
  gap: var(--space-10);
  grid-template-columns: 1fr;
  margin-bottom: var(--space-12);
}
@media (min-width: 40em) { .footer-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 64em) { .footer-grid { grid-template-columns: 2fr 1fr 1fr 1fr; } }

.footer-brand .site-logo {
  color: var(--color-white);
  font-size: var(--text-xl);
  font-weight: 800;
  margin-bottom: var(--space-4);
  display: block;
  letter-spacing: -0.035em;
}
.footer-brand .site-logo:hover { color: var(--color-teal-light); }
.footer-brand p { font-size: var(--text-sm); line-height: var(--leading-loose); opacity: 0.65; max-width: 280px; }

.footer-nav h3 {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 700;
  color: rgba(255,255,255,0.45);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-4);
}
.footer-nav ul { list-style: none; padding: 0; }
.footer-nav li { margin-bottom: var(--space-2); }
.footer-nav a {
  font-size: var(--text-sm);
  color: rgba(255,255,255,0.65);
  text-decoration: none;
  transition: color var(--transition);
}
.footer-nav a:hover { color: var(--color-teal-light); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: var(--space-6);
  font-size: var(--text-xs);
  opacity: 0.5;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
@media (min-width: 48em) {
  .footer-bottom { flex-direction: row; justify-content: space-between; align-items: flex-start; }
}

/* --- Typography ----------------------------------------------------------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: var(--leading-snug);
  color: var(--color-blue);
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(var(--text-xl), 4vw, var(--text-2xl)); font-weight: 500; margin-bottom: var(--space-5); }
h2 { font-size: clamp(var(--text-lg), 3vw, var(--text-xl)); margin-top: var(--space-12); margin-bottom: var(--space-4); }
h3 { font-size: clamp(var(--text-md), 2.5vw, var(--text-lg)); margin-top: var(--space-8); margin-bottom: var(--space-3); }
h4 { font-size: var(--text-md); font-weight: 600; margin-top: var(--space-6); margin-bottom: var(--space-2); }

p { margin-bottom: var(--space-5); }
p:last-child { margin-bottom: 0; }

strong { font-weight: 700; }
em { font-style: italic; }

code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--color-bg-code);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
  color: var(--color-blue);
}

pre {
  background: var(--color-bg-dark);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-md);
  padding: var(--space-5);
  overflow-x: auto;
  margin-bottom: var(--space-6);
}
pre code { background: none; padding: 0; color: rgba(255,255,255,0.85); }

blockquote {
  border-left: 4px solid var(--color-teal);
  padding: var(--space-4) var(--space-6);
  margin: var(--space-6) 0;
  background: var(--color-bg-alt);
  border-radius: 0 var(--radius) var(--radius) 0;
}
blockquote p { color: var(--color-text-muted); font-style: italic; margin-bottom: 0; }

hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-12) 0;
}

/* --- Article Layout ------------------------------------------------------- */
.article-header {
  padding: var(--space-10) 0 var(--space-6);
  border-bottom: 1px solid var(--color-border-light);
  margin-bottom: var(--space-8);
}

.article-header .breadcrumb { margin-bottom: var(--space-4); }

.article-title {
  font-size: clamp(var(--text-xl), 4.5vw, var(--text-2xl));
  font-weight: 500;
  line-height: var(--leading-tight);
  color: var(--color-blue);
  letter-spacing: -0.03em;
  margin-bottom: var(--space-5);
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}
.article-meta a { color: var(--color-text-muted); }
.article-meta .meta-sep { opacity: 0.4; }

.article-summary {
  font-size: var(--text-md);
  line-height: var(--leading-base);
  color: var(--color-text-muted);
  margin-top: var(--space-5);
  max-width: 680px;
}

.research-note {
  font-size: var(--text-xs);
  color: var(--color-text-light);
  font-style: italic;
  margin-top: var(--space-4);
  border-top: 1px solid var(--color-border-light);
  padding-top: var(--space-3);
}

/* Article body */
.article-body { max-width: var(--max-width-content); }
.article-body h2 { scroll-margin-top: 5rem; }
.article-body h3 { scroll-margin-top: 5rem; }

.article-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
  padding: var(--space-8) 0 var(--space-16);
}
@media (min-width: 80em) {
  .article-layout {
    grid-template-columns: var(--max-width-content) 240px;
    align-items: start;
    gap: var(--space-16);
  }
}

/* Sidebar TOC */
.toc-sidebar {
  display: none;
  position: sticky;
  top: 5rem;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
}
@media (min-width: 80em) { .toc-sidebar { display: block; } }

.toc-sidebar h2 {
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-light);
  margin: 0 0 var(--space-3);
}
.toc-sidebar ol { list-style: none; padding: 0; }
.toc-sidebar li {
  margin-bottom: 1px;
  border-left: 2px solid var(--color-border-light);
  padding-left: var(--space-3);
}
.toc-sidebar li.active { border-left-color: var(--color-teal); }
.toc-sidebar a {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-decoration: none;
  display: block;
  padding: var(--space-1) 0;
  transition: color var(--transition);
}
.toc-sidebar a:hover { color: var(--color-blue); }
.toc-sidebar li.active a { color: var(--color-teal); font-weight: 700; }

/* Inline TOC */
.toc-inline {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-blue);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: var(--space-5) var(--space-6);
  margin: var(--space-8) 0;
}
.toc-inline h2 {
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-blue);
  margin: 0 0 var(--space-3);
}
.toc-inline ol { padding-left: var(--space-5); margin: 0; }
.toc-inline li { margin-bottom: var(--space-2); }
.toc-inline a { font-size: var(--text-sm); font-weight: 500; color: var(--color-blue); text-decoration: none; }
.toc-inline a:hover { text-decoration: underline; color: var(--color-teal); }

/* --- Key Takeaways Box ---------------------------------------------------- */
.takeaways {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-teal);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: var(--space-5) var(--space-6);
  margin: var(--space-6) 0 var(--space-8);
  box-shadow: var(--shadow-sm);
}
.takeaways h2 {
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-teal);
  margin: 0 0 var(--space-3);
}
.takeaways ul { padding-left: var(--space-5); margin: 0; }
.takeaways li {
  font-size: var(--text-sm);
  line-height: var(--leading-base);
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

/* --- Breadcrumb ----------------------------------------------------------- */
.breadcrumb {
  font-size: var(--text-xs);
  font-weight: 500;
  color: var(--color-text-light);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
}
.breadcrumb a { color: var(--color-text-muted); text-decoration: none; }
.breadcrumb a:hover { color: var(--color-teal); text-decoration: underline; }
.breadcrumb .sep { color: var(--color-border); margin: 0 var(--space-1); }
.breadcrumb [aria-current="page"] { color: var(--color-text-muted); }

/* --- Tables --------------------------------------------------------------- */
.table-wrap {
  overflow-x: auto;
  margin: var(--space-6) 0;
  border-radius: var(--radius-md);
  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);
}
caption {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-align: left;
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border-light);
  font-style: italic;
}
th {
  background: var(--color-bg-dark);
  color: rgba(255,255,255,0.8);
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.07em;
  text-align: left;
  padding: var(--space-3) var(--space-4);
  white-space: nowrap;
}
td {
  padding: var(--space-3) var(--space-4);
  border-top: 1px solid var(--color-border-light);
  color: var(--color-text);
  vertical-align: top;
}
tr:hover td { background: var(--color-bg-alt); }
tr:hover th[scope="row"] { background: var(--color-bg-alt); }
th[scope="row"] {
  font-weight: 700;
  font-size: var(--text-sm);
  text-transform: none;
  letter-spacing: 0;
  color: var(--color-text);
  background: var(--color-bg-alt);
  white-space: nowrap;
}

/* Sortable */
th[data-sort] { cursor: pointer; user-select: none; }
th[data-sort]::after { content: ' ↕'; opacity: 0.4; font-size: 0.75em; }
th[data-sort="asc"]::after  { content: ' ↑'; opacity: 1; }
th[data-sort="desc"]::after { content: ' ↓'; opacity: 1; }

/* --- Cards ---------------------------------------------------------------- */
.card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-top: 3px solid transparent;
  border-radius: var(--radius-md);
  padding: var(--space-6);
  transition: box-shadow var(--transition), border-top-color var(--transition), transform var(--transition);
}
.card:hover {
  box-shadow: var(--shadow-md);
  border-top-color: var(--color-teal);
  transform: translateY(-2px);
}
.card-link { text-decoration: none; display: block; }
.card-link:hover .card {
  border-top-color: var(--color-accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card-tag {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-teal);
  margin-bottom: var(--space-3);
}
.card-title {
  font-family: var(--font-sans);
  font-size: var(--text-md);
  font-weight: 700;
  color: var(--color-blue);
  letter-spacing: -0.015em;
  margin-bottom: var(--space-2);
  line-height: var(--leading-snug);
}
.card-link:hover .card-title { color: var(--color-teal); }
.card-desc { font-size: var(--text-sm); color: var(--color-text-muted); line-height: var(--leading-base); }

/* Silo card grid */
.silo-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}
@media (min-width: 36em) { .silo-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 60em) { .silo-grid { grid-template-columns: repeat(3, 1fr); } }

/* Article list */
.article-list { display: flex; flex-direction: column; gap: var(--space-4); }
.article-list-item {
  display: grid;
  gap: var(--space-3);
  padding-bottom: var(--space-4);
  border-bottom: 1px solid var(--color-border-light);
}
.article-list-item:last-child { border-bottom: none; }
.article-list-title { font-family: var(--font-sans); font-size: var(--text-md); font-weight: 700; color: var(--color-blue); letter-spacing: -0.01em; }
.article-list-title a { text-decoration: none; }
.article-list-title a:hover { color: var(--color-teal); text-decoration: underline; }
.article-list-desc { font-size: var(--text-sm); color: var(--color-text-muted); }
.article-list-date { font-size: var(--text-xs); color: var(--color-text-light); }

/* --- Hero (Homepage) ------------------------------------------------------ */
.hero {
  background-color: var(--color-bg-dark);
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  color: var(--color-white);
  padding: var(--space-24) 0 calc(var(--space-20) + 4rem);
  position: relative;
  overflow: hidden;
}

/* Diagonal bottom edge */
.hero::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 5rem;
  background: var(--color-bg);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
}

/* Teal accent glow in corner */
.hero::before {
  content: '';
  position: absolute;
  top: -10%;
  right: -5%;
  width: 50%;
  height: 80%;
  background: radial-gradient(ellipse at center, rgba(11,140,141,0.15) 0%, transparent 65%);
  pointer-events: none;
}

.hero-inner { position: relative; z-index: 1; max-width: 720px; }

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-teal-light);
  margin-bottom: var(--space-5);
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 2rem;
  height: 2px;
  background: var(--color-teal);
  border-radius: 1px;
  flex-shrink: 0;
}

.hero-title {
  font-family: var(--font-sans);
  font-size: clamp(var(--text-xl), 5vw, var(--text-3xl));
  font-weight: 500;
  line-height: 1.08;
  color: var(--color-white);
  letter-spacing: -0.035em;
  margin-bottom: var(--space-6);
}

.hero-desc {
  font-size: var(--text-md);
  line-height: var(--leading-base);
  color: rgba(255,255,255,0.72);
  margin-bottom: var(--space-8);
  max-width: 540px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-3); }

/* --- Buttons -------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition), transform var(--transition);
  white-space: nowrap;
}
.btn:focus-visible { outline: 2px solid var(--color-teal); outline-offset: 3px; }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--color-accent);
  color: var(--color-white);
  border-color: var(--color-accent);
  box-shadow: 0 2px 8px rgba(201,102,16,0.3);
}
.btn-primary:hover {
  background: var(--color-accent-light);
  border-color: var(--color-accent-light);
  color: var(--color-white);
  box-shadow: 0 4px 16px rgba(201,102,16,0.4);
}

.btn-outline-white {
  background: transparent;
  color: var(--color-white);
  border-color: rgba(255,255,255,0.35);
}
.btn-outline-white:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.6);
  color: var(--color-white);
}

.btn-outline {
  background: transparent;
  color: var(--color-blue);
  border-color: var(--color-border);
}
.btn-outline:hover { border-color: var(--color-teal); color: var(--color-teal); background: rgba(11,140,141,0.04); }

.btn-teal {
  background: var(--color-teal);
  color: var(--color-white);
  border-color: var(--color-teal);
}
.btn-teal:hover { background: var(--color-teal-light); border-color: var(--color-teal-light); color: var(--color-white); }

.btn-sm { font-size: var(--text-xs); padding: 0.5rem 1rem; }
.btn-lg { font-size: var(--text-base); padding: 0.875rem 2rem; }

/* --- Section Layouts ------------------------------------------------------ */
.section { padding: var(--space-16) 0; }
.section-alt { background: var(--color-bg-alt); }

.section-dark {
  background-color: var(--color-bg-dark);
  background-image:
    linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.025) 1px, transparent 1px);
  background-size: 48px 48px;
  color: var(--color-white);
}

.section-header { margin-bottom: var(--space-10); }

.section-label {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-accent);
  margin-bottom: var(--space-3);
}
.section-label::before {
  content: '';
  display: inline-block;
  width: 1.5rem;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  flex-shrink: 0;
}
.section-dark .section-label { color: var(--color-teal-light); }
.section-dark .section-label::before { background: var(--color-teal-light); }

.section-title {
  font-family: var(--font-sans);
  font-size: clamp(var(--text-lg), 3vw, var(--text-xl));
  font-weight: 800;
  color: var(--color-blue);
  letter-spacing: -0.025em;
  margin-bottom: var(--space-3);
}
.section-dark .section-title { color: var(--color-white); }

.section-desc { font-size: var(--text-md); color: var(--color-text-muted); max-width: 560px; line-height: var(--leading-base); }
.section-dark .section-desc { color: rgba(255,255,255,0.65); }

/* --- Tools Cards (dark section) ------------------------------------------ */
.tools-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}
@media (min-width: 36em) { .tools-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 64em) { .tools-grid { grid-template-columns: repeat(4, 1fr); } }

.tool-card {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-top: 2px solid var(--color-teal);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  text-decoration: none;
  display: block;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
}
.tool-card:hover {
  background: rgba(255,255,255,0.09);
  border-color: rgba(255,255,255,0.2);
  border-top-color: var(--color-accent);
  transform: translateY(-2px);
}
.tool-card-icon { font-size: 1.75rem; margin-bottom: var(--space-4); }
.tool-card-title {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-2);
}
.tool-card-desc { font-size: var(--text-sm); color: rgba(255,255,255,0.58); line-height: var(--leading-base); }

/* --- Pillar Page ---------------------------------------------------------- */
.pillar-intro {
  padding: var(--space-10) 0 var(--space-8);
  border-bottom: 2px solid var(--color-border-light);
  margin-bottom: var(--space-10);
}

.pillar-intro h1 {
  font-size: clamp(var(--text-xl), 4.5vw, var(--text-2xl));
  font-weight: 500;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-5);
}

.pillar-summary {
  font-size: var(--text-md);
  color: var(--color-text-muted);
  line-height: var(--leading-base);
  margin-bottom: var(--space-6);
}

.pillar-body { }

.pillar-articles-section { padding: var(--space-12) 0; }
.pillar-articles-section h2 {
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-4);
  border-bottom: 2px solid var(--color-border-light);
}

.article-coming-soon {
  opacity: 0.55;
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-style: italic;
}

/* --- Calculator / Tool Pages --------------------------------------------- */
.tool-hero {
  background-color: var(--color-bg-dark);
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  color: var(--color-white);
  padding: var(--space-10) 0 var(--space-12);
  position: relative;
  overflow: hidden;
}
.tool-hero::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 3.5rem;
  background: var(--color-bg);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
}

.tool-hero-title {
  font-family: var(--font-sans);
  font-size: clamp(var(--text-xl), 4vw, var(--text-2xl));
  font-weight: 500;
  color: var(--color-white);
  letter-spacing: -0.03em;
  margin-bottom: var(--space-4);
}
.tool-hero-desc { font-size: var(--text-md); color: rgba(255,255,255,0.72); max-width: 560px; }

.tool-card-main {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--color-teal);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--space-8);
  margin-top: calc(-1 * var(--space-8));
  position: relative;
  z-index: 1;
}
@media (min-width: 60em) { .tool-card-main { padding: var(--space-10) var(--space-12); } }

.tool-section-title {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-5);
  padding-bottom: var(--space-3);
  border-bottom: 2px solid var(--color-border-light);
}

/* Mode tabs */
[role="tablist"] {
  display: flex;
  gap: 2px;
  background: var(--color-bg-alt);
  padding: 3px;
  border-radius: var(--radius);
  width: fit-content;
  margin-bottom: var(--space-6);
  border: 1px solid var(--color-border);
}
[role="tab"] {
  padding: var(--space-2) var(--space-5);
  font-size: var(--text-sm);
  font-weight: 600;
  border: none;
  background: transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--color-text-muted);
  transition: background var(--transition), color var(--transition);
}
[role="tab"][aria-selected="true"] {
  background: var(--color-white);
  color: var(--color-blue);
  box-shadow: var(--shadow-sm);
}

/* Form fields */
.form-group { margin-bottom: var(--space-5); }
.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}
.form-group .hint {
  display: block;
  font-size: var(--text-xs);
  color: var(--color-text-light);
  margin-bottom: var(--space-2);
}
.form-row { display: grid; gap: var(--space-5); grid-template-columns: 1fr; }
@media (min-width: 36em) { .form-row { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 60em) { .form-row { grid-template-columns: repeat(3, 1fr); } }

input[type="number"],
input[type="text"],
select {
  width: 100%;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  color: var(--color-text);
  background: var(--color-bg);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-3) var(--space-4);
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
}
input[type="number"]:focus,
input[type="text"]:focus,
select:focus {
  outline: none;
  border-color: var(--color-teal);
  box-shadow: 0 0 0 3px rgba(11,140,141,0.12);
  background: var(--color-white);
}
.input-with-unit { position: relative; }
.input-with-unit input { padding-right: 3.5rem; }
.input-unit {
  position: absolute;
  right: var(--space-3);
  top: 50%;
  transform: translateY(-50%);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-text-light);
  pointer-events: none;
}

/* Results panel */
.results-panel {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--color-teal);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  margin-top: var(--space-6);
}
.results-panel.hidden { display: none; }

.result-score { text-align: center; padding: var(--space-8) 0; }
.result-score-number {
  font-family: var(--font-sans);
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.04em;
  margin-bottom: var(--space-2);
}
.result-score-label {
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
}
.score-good    { color: #166534; }
.score-fair    { color: #92400E; }
.score-poor    { color: #B91C1C; }
.score-world   { color: #1D4ED8; }

.result-breakdown { margin-top: var(--space-6); }
.result-breakdown h3 {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}
.breakdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
  font-size: var(--text-sm);
}
.breakdown-label { flex: 0 0 120px; font-weight: 600; color: var(--color-text-muted); }
.breakdown-bar-wrap { flex: 1; background: var(--color-border-light); border-radius: 2px; height: 8px; overflow: hidden; }
.breakdown-bar { height: 100%; border-radius: 2px; background: var(--color-teal); transition: width 0.5s cubic-bezier(0.22,1,0.36,1); }
.breakdown-value { flex: 0 0 50px; text-align: right; font-weight: 700; color: var(--color-text); }

.result-interpretation {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-blue);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: var(--space-5);
  margin-top: var(--space-5);
  font-size: var(--text-sm);
}
.result-interpretation p { margin-bottom: var(--space-3); }
.result-interpretation p:last-child { margin-bottom: 0; }

/* --- FAQ ------------------------------------------------------------------ */
.faq-list { margin: var(--space-8) 0; }
.faq-item {
  border-bottom: 1px solid var(--color-border-light);
  padding: var(--space-5) 0;
}
.faq-item:first-child { border-top: 1px solid var(--color-border-light); }
.faq-q {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--color-blue);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
}
.faq-a { font-size: var(--text-sm); color: var(--color-text-muted); line-height: var(--leading-base); }
.faq-a p { margin-bottom: var(--space-2); }
.faq-a p:last-child { margin-bottom: 0; }

/* --- Sources -------------------------------------------------------------- */
.sources-section {
  margin-top: var(--space-12);
  padding-top: var(--space-8);
  border-top: 2px solid var(--color-border-light);
}
.sources-section h2 {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin: 0 0 var(--space-4);
}
.sources-list { list-style: none; padding: 0; }
.sources-list li { font-size: var(--text-xs); color: var(--color-text-muted); margin-bottom: var(--space-2); line-height: var(--leading-base); }
.sources-list a { color: var(--color-text-muted); word-break: break-all; }

/* --- Utility Classes ------------------------------------------------------ */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
}
.text-center { text-align: center; }
.text-right  { text-align: right; }
.text-muted  { color: var(--color-text-muted); }
.text-sm     { font-size: var(--text-sm); }
.text-xs     { font-size: var(--text-xs); }
.mt-0 { margin-top: 0 !important; }

/* --- Decision Box --------------------------------------------------------- */
.decision-box {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin: var(--space-8) 0;
  box-shadow: var(--shadow-sm);
}
.decision-box-header {
  background: linear-gradient(100deg, var(--color-bg-dark) 0%, var(--color-blue) 100%);
  color: var(--color-white);
  padding: var(--space-4) var(--space-6);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 700;
  letter-spacing: -0.01em;
}
.decision-cols {
  display: grid;
  grid-template-columns: 1fr;
}
@media (min-width: 48em) { .decision-cols { grid-template-columns: 1fr 1fr; } }
.decision-col {
  padding: var(--space-5) var(--space-6);
  background: var(--color-white);
}
.decision-col + .decision-col { border-top: 1px solid var(--color-border-light); }
@media (min-width: 48em) {
  .decision-col + .decision-col { border-top: none; border-left: 1px solid var(--color-border-light); }
}
.decision-col h3 {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-teal);
  margin: 0 0 var(--space-3);
}
.decision-col ul { list-style: none; padding: 0; margin: 0; }
.decision-col li {
  font-size: var(--text-sm);
  padding: var(--space-2) 0 var(--space-2) var(--space-4);
  border-bottom: 1px solid var(--color-border-light);
  position: relative;
}
.decision-col li:last-child { border-bottom: none; }
.decision-col li::before { content: '→'; position: absolute; left: 0; color: var(--color-accent); font-size: var(--text-xs); top: 0.55em; font-weight: 700; }

/* --- Pricing Note --------------------------------------------------------- */
.pricing-note {
  font-size: var(--text-xs);
  color: var(--color-text-light);
  font-style: italic;
  margin-top: var(--space-2);
}

/* --- Briefings / News ----------------------------------------------------- */
.briefing-dateline {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-4);
  border-bottom: 2px solid var(--color-border-light);
}
.briefing-dateline .date { font-weight: 700; }
.briefing-dateline .tag {
  display: inline-block;
  background: var(--color-accent);
  color: var(--color-white);
  font-size: var(--text-xs);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  padding: 0.25em 0.65em;
  border-radius: var(--radius-sm);
}

/* Alert / notice banner */
.notice {
  background: var(--color-warning-bg);
  border: 1px solid #FCD34D;
  border-left: 4px solid #D97706;
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: var(--space-4) var(--space-5);
  margin: var(--space-6) 0;
  font-size: var(--text-sm);
}
.notice p { margin-bottom: 0; color: #78350F; }

/* --- Page Header (non-article) ------------------------------------------- */
.page-header {
  padding: var(--space-10) 0 var(--space-8);
  border-bottom: 2px solid var(--color-border-light);
  margin-bottom: var(--space-8);
}
.page-header h1 { margin-bottom: var(--space-3); letter-spacing: -0.03em; }
.page-header p { font-size: var(--text-md); color: var(--color-text-muted); max-width: 640px; }

/* --- Glossary ------------------------------------------------------------- */
.glossary-index {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-8);
}
.glossary-index a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  font-weight: 800;
  font-size: var(--text-sm);
  color: var(--color-blue);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius);
  text-decoration: none;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.glossary-index a:hover {
  background: var(--color-blue);
  color: var(--color-white);
  border-color: var(--color-blue);
}

.glossary-group { margin-bottom: var(--space-10); scroll-margin-top: 5rem; }
.glossary-group h2 {
  font-size: var(--text-sm);
  font-family: var(--font-sans);
  font-weight: 800;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 2px solid var(--color-border-light);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-5);
  margin-top: 0;
}

.glossary-term { margin-bottom: var(--space-6); scroll-margin-top: 5rem; }
.glossary-term dt {
  font-family: var(--font-sans);
  font-size: var(--text-md);
  font-weight: 700;
  color: var(--color-blue);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-2);
}
.glossary-term dd {
  font-size: var(--text-sm);
  color: var(--color-text);
  line-height: var(--leading-base);
  margin-left: 0;
}

/* --- Page Feature Image --------------------------------------------------- */
.page-feature-img {
  margin: var(--space-6) 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  line-height: 0; /* remove gap under img */
}
.page-feature-img img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
  transition: transform 0.4s ease;
}
@media (min-width: 48em) { .page-feature-img img { height: 300px; } }
@media (min-width: 64em) { .page-feature-img img { height: 360px; } }
.page-feature-img:hover img { transform: scale(1.02); }
.page-feature-img figcaption {
  position: absolute;
  bottom: 0;
  right: 0;
  background: rgba(0,0,0,0.55);
  color: rgba(255,255,255,0.65);
  font-size: 0.6rem;
  padding: 0.2rem 0.5rem;
  line-height: 1.4;
}
.page-feature-img figcaption a { color: rgba(255,255,255,0.65); text-decoration: none; }
.page-feature-img figcaption a:hover { color: var(--color-white); }

/* Tool card SVG icons */
.tool-card-icon {
  width: 2.75rem;
  height: 2.75rem;
  color: var(--color-teal-light);
  margin-bottom: var(--space-4);
  display: block;
}
.tool-card:hover .tool-card-icon { color: var(--color-accent-light); }

/* --- Print ---------------------------------------------------------------- */
@media print {
  .site-header, .site-footer, .nav-toggle, .toc-sidebar { display: none; }
  body { background: white; color: black; font-size: 11pt; }
  a { color: black; }
  .hero { background: white; color: black; }
}