/* hbelc.org — Building Biology & Healthy Home Science
   Design: Scientific field journal meets natural health
   Calm, authoritative, evidence-based. */

/* ── Variables ─────────────────────────────────────────────────── */

:root {
  --color-bg: #f5f3ef;
  --color-surface: #ffffff;
  --color-text: #242320;
  --color-text-secondary: #6b6860;

  --color-accent: #1f4e38;
  --color-accent-light: #27654a;
  --color-accent-subtle: #eef4f0;

  --color-warning: #b5860d;
  --color-danger: #a02020;

  --color-border: #ddd9d1;
  --color-nav-bg: #1a3f2e;
  --color-nav-text: #f0ece4;

  --color-concern-none: #2d7a47;
  --color-concern-slight: #b5860d;
  --color-concern-severe: #c4521a;
  --color-concern-extreme: #a02020;

  --color-concern-none-tint: #f0f7f2;
  --color-concern-slight-tint: #fdf8ed;
  --color-concern-severe-tint: #fdf3ee;
  --color-concern-extreme-tint: #fdf0f0;

  --font-body: Georgia, "Times New Roman", Times, serif;
  --font-heading: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "Consolas", "Menlo", "Monaco", "Courier New", monospace;

  --content-width: 720px;
  --wide-width: 900px;
  --layout-width: 1100px;
  --toc-width: 220px;
}


/* ── Reset ─────────────────────────────────────────────────────── */

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

html {
  font-size: 106.25%; /* 17px base */
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-accent); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--color-accent-light); }


/* ── Typography ────────────────────────────────────────────────── */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--color-text);
  line-height: 1.3;
}

h1 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 0.5em;
}

h2 {
  font-size: 1.45rem;
  font-weight: 600;
  margin-top: 2.5em;
  margin-bottom: 0.75em;
  padding-left: 0.75em;
  border-left: 3px solid var(--color-accent);
}

h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 2em;
  margin-bottom: 0.5em;
}

h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-top: 1.5em;
  margin-bottom: 0.4em;
}

p { margin-bottom: 1.2em; }

ul, ol {
  margin-bottom: 1.2em;
  padding-left: 1.5em;
}

li { margin-bottom: 0.35em; }

li > ul, li > ol { margin-top: 0.35em; margin-bottom: 0; }

blockquote {
  margin: 1.5em 0;
  padding: 1em 1.25em;
  border-left: 3px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text-secondary);
  font-style: italic;
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--color-accent-subtle);
  padding: 0.15em 0.35em;
  border-radius: 3px;
}

pre {
  margin: 1.5em 0;
  padding: 1.25em;
  background: #2b2b28;
  color: #e8e6e0;
  border-radius: 4px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.6;
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 2.5em 0;
}

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


/* ── Navigation ────────────────────────────────────────────────── */

.site-header {
  background: var(--color-nav-bg);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 1px 3px rgba(0,0,0,0.15);
}

.nav-container {
  max-width: var(--layout-width);
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-nav-text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.nav-logo:hover { color: #ffffff; }

.nav-links {
  list-style: none;
  display: flex;
  gap: 0.25rem;
  padding: 0;
  margin: 0;
}

.nav-links a {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-nav-text);
  text-decoration: none;
  padding: 0.5em 0.75em;
  border-radius: 4px;
  transition: background 0.15s;
}

.nav-links a:hover {
  background: rgba(255,255,255,0.1);
  color: #ffffff;
}

/* Hamburger */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle__bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-nav-text);
  border-radius: 1px;
  transition: transform 0.2s, opacity 0.2s;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media (max-width: 899px) {
  .nav-toggle { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background: var(--color-nav-bg);
    flex-direction: column;
    padding: 0.5rem 1.25rem 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
  }

  .nav-links.is-open { display: flex; }

  .nav-links a {
    padding: 0.65em 0;
    font-size: 0.95rem;
  }
}


/* ── Breadcrumb ────────────────────────────────────────────────── */

.breadcrumb {
  font-family: var(--font-heading);
  font-size: 0.82rem;
  color: var(--color-text-secondary);
  margin-bottom: 1rem;
}

.breadcrumb a {
  color: var(--color-text-secondary);
  text-decoration: none;
}

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

.breadcrumb span[aria-hidden] { margin: 0 0.35em; }


/* ── Article Header ────────────────────────────────────────────── */

.article-header { margin-bottom: 2rem; }

.article-header h1 { margin-bottom: 0.4em; }

.lede {
  font-size: 1.1rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
  max-width: var(--content-width);
}


/* ── Guide Layout (3-column with ToC) ──────────────────────────── */

.guide-layout {
  max-width: var(--layout-width);
  margin: 0 auto;
  padding: 2rem 1.25rem;
  display: grid;
  grid-template-columns: var(--toc-width) 1fr;
  gap: 2.5rem;
}

.guide-main {
  min-width: 0;
}

.guide-body {
  max-width: var(--content-width);
}

/* Ensure tables can overflow on guide pages */
.guide-body .table-wrap {
  max-width: calc(100vw - var(--toc-width) - 6rem);
}

@media (max-width: 899px) {
  .guide-layout {
    display: block;
    padding: 1.25rem 1rem;
  }

  .toc-rail { margin-bottom: 1.5rem; }

  .guide-body { max-width: 100%; }
}


/* ── ToC Rail ──────────────────────────────────────────────────── */

.toc-rail {
  align-self: start;
}

.toc-nav {
  position: sticky;
  top: 72px;
  max-height: calc(100vh - 88px);
  overflow-y: auto;
}

.toc-nav__title {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-secondary);
  margin-bottom: 0.75rem;
}

.toc-nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.toc-nav li { margin-bottom: 0; }

.toc-nav a {
  display: block;
  font-family: var(--font-heading);
  font-size: 0.8rem;
  line-height: 1.4;
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 0.3em 0 0.3em 0.75em;
  border-left: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}

.toc-nav a:hover {
  color: var(--color-accent);
}

.toc-nav a.toc-active {
  color: var(--color-accent);
  font-weight: 600;
  border-left-color: var(--color-accent);
}

/* H3-level indent */
.toc-nav .toc-h3 a {
  padding-left: 1.5em;
  font-size: 0.78rem;
}

/* Mobile ToC disclosure */
.toc-mobile-details {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 0;
}

.toc-mobile-details summary {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-accent);
  padding: 0.75em 1em;
  cursor: pointer;
  list-style: none;
}

.toc-mobile-details summary::-webkit-details-marker { display: none; }
.toc-mobile-details summary::marker { display: none; content: ""; }

.toc-mobile-details summary::before {
  content: "\25B6\00a0";
  font-size: 0.7em;
  transition: transform 0.15s;
  display: inline-block;
}

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

.toc-mobile-details .toc-nav {
  position: static;
  max-height: none;
  padding: 0 1em 0.75em;
}


/* ── Homepage ──────────────────────────────────────────────────── */

/* Hero */
.hero {
  background: var(--color-nav-bg);
  color: var(--color-nav-text);
  text-align: center;
  padding: 4rem 1.25rem;
}

.hero-inner { max-width: 640px; margin: 0 auto; }

.hero-title {
  font-size: 2.4rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.5em;
  line-height: 1.2;
}

.hero-tagline {
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.7;
  color: rgba(240, 236, 228, 0.85);
  margin-bottom: 1.75em;
}

.hero-cta { display: flex; gap: 0.75rem; justify-content: center; flex-wrap: wrap; }

/* Buttons */
.btn {
  font-family: var(--font-heading);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  padding: 0.7em 1.5em;
  border-radius: 4px;
  transition: background 0.15s, color 0.15s;
  display: inline-block;
}

.btn--primary {
  background: #ffffff;
  color: var(--color-nav-bg);
}

.btn--primary:hover {
  background: var(--color-nav-text);
  color: var(--color-nav-bg);
}

.btn--outline {
  background: transparent;
  color: #ffffff;
  border: 1.5px solid rgba(255,255,255,0.5);
}

.btn--outline:hover {
  border-color: #ffffff;
  background: rgba(255,255,255,0.08);
  color: #ffffff;
}

/* Topic Cards */
.topic-cards {
  max-width: var(--wide-width);
  margin: 0 auto;
  padding: 3rem 1.25rem;
}

.topic-cards__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.topic-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 1.75rem 1.5rem;
  text-decoration: none;
  color: var(--color-text);
  transition: box-shadow 0.15s, border-color 0.15s;
}

.topic-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  color: var(--color-text);
}

.topic-card__icon {
  color: var(--color-accent);
  margin-bottom: 1rem;
}

.topic-card__title {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5em;
  color: var(--color-accent);
}

.topic-card__desc {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

@media (max-width: 680px) {
  .topic-cards__grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 1.8rem; }
  .hero { padding: 2.5rem 1.25rem; }
}

/* Homepage Body */
.homepage-body {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 1.25rem 3rem;
}

.content-wrap h2:first-child { margin-top: 0; }


/* ── Comparison Layout ─────────────────────────────────────────── */

.comparison-main {
  max-width: var(--wide-width);
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
}

.comparison-body { max-width: 100%; }


/* ── Simple Layout ─────────────────────────────────────────────── */

.simple-main {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
}


/* ── Tables ────────────────────────────────────────────────────── */

.table-wrap {
  overflow-x: auto;
  margin: 1.5em 0;
  -webkit-overflow-scrolling: touch;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  line-height: 1.5;
  margin: 1.5em 0;
}

thead th {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.82rem;
  text-align: left;
  background: #eae6de;
  color: var(--color-text);
  padding: 0.65em 0.85em;
  border-bottom: 2px solid var(--color-border);
  white-space: nowrap;
}

tbody td {
  padding: 0.6em 0.85em;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
}

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

/* Alternating rows for standard tables */
tbody tr:nth-child(even) { background: rgba(0,0,0,0.015); }


/* ── Concern Level Table Rows ──────────────────────────────────── */

tr.concern-none td {
  background: var(--color-concern-none-tint);
  border-left: 4px solid var(--color-concern-none);
}

tr.concern-none td:not(:first-child) { border-left: none; }
tr.concern-none td:first-child { border-left: 4px solid var(--color-concern-none); }

tr.concern-slight td {
  background: var(--color-concern-slight-tint);
}

tr.concern-slight td:first-child { border-left: 4px solid var(--color-concern-slight); }

tr.concern-severe td {
  background: var(--color-concern-severe-tint);
}

tr.concern-severe td:first-child { border-left: 4px solid var(--color-concern-severe); }

tr.concern-extreme td {
  background: var(--color-concern-extreme-tint);
}

tr.concern-extreme td:first-child { border-left: 4px solid var(--color-concern-extreme); }

/* Remove alternating bg for concern rows */
tr[class^="concern-"]:nth-child(even) td,
tr[class*=" concern-"]:nth-child(even) td {
  /* Concern tint takes priority */
}


/* ── Concern Level Pill Badges ─────────────────────────────────── */

.concern {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.25em 0.65em;
  border-radius: 999px;
  color: #ffffff;
  white-space: nowrap;
  vertical-align: middle;
}

.concern--none     { background: var(--color-concern-none); }
.concern--slight   { background: var(--color-concern-slight); }
.concern--severe   { background: var(--color-concern-severe); }
.concern--extreme  { background: var(--color-concern-extreme); }


/* ── Callout Boxes ─────────────────────────────────────────────── */

.callout {
  margin: 1.75em 0;
  padding: 1.15em 1.25em;
  border-radius: 4px;
  border-left: 4px solid;
  font-size: 0.94rem;
}

.callout > *:last-child { margin-bottom: 0; }

.callout--info {
  border-left-color: var(--color-accent);
  background: var(--color-accent-subtle);
}

.callout--warning {
  border-left-color: var(--color-warning);
  background: var(--color-concern-slight-tint);
}

.callout--disclaimer {
  border-left-color: var(--color-border);
  background: #f9f8f5;
  color: var(--color-text-secondary);
  font-size: 0.88rem;
}


/* ── Measurement Values ────────────────────────────────────────── */

.val {
  font-family: var(--font-mono);
  font-size: 0.92em;
  font-weight: 600;
}


/* ── Footer ────────────────────────────────────────────────────── */

.site-footer {
  background: var(--color-nav-bg);
  color: var(--color-nav-text);
  margin-top: 3rem;
}

.footer-container {
  max-width: var(--layout-width);
  margin: 0 auto;
  padding: 2.5rem 1.25rem 2rem;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 2rem;
}

.footer-brand {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.5em;
}

.footer-tagline {
  font-size: 0.85rem;
  line-height: 1.6;
  color: rgba(240,236,228,0.75);
}

.footer-heading {
  font-family: var(--font-heading);
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: rgba(240,236,228,0.55);
  margin-bottom: 0.75em;
}

.footer-col ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-col li { margin-bottom: 0.3em; }

.footer-col a {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  color: var(--color-nav-text);
  text-decoration: none;
}

.footer-col a:hover { color: #ffffff; text-decoration: underline; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 1rem 1.25rem;
  text-align: center;
}

.footer-bottom p {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  color: rgba(240,236,228,0.5);
  margin: 0;
  max-width: var(--layout-width);
  margin: 0 auto;
}

@media (max-width: 680px) {
  .footer-container {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}


/* ── Utility ───────────────────────────────────────────────────── */

.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;
}


/* ── Print ─────────────────────────────────────────────────────── */

@media print {
  .site-header,
  .site-footer,
  .toc-rail,
  .nav-toggle { display: none; }

  body { background: #fff; color: #000; font-size: 11pt; }

  .guide-layout { display: block; }
  .guide-body { max-width: 100%; }

  a { color: #000; text-decoration: underline; }
  a[href]::after { content: " (" attr(href) ")"; font-size: 0.8em; }
}