/* ============================================================
   DryerVentGuide.pages.dev — Main Stylesheet
   Aesthetic: Industrial utility meets clean editorial.
   Palette: Warm off-white, deep charcoal, safety orange accent,
            muted steel blue secondary.
   Fonts: Oswald (headings) + Source Serif 4 (body)
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Oswald:wght@400;500;600;700&family=Source+Serif+4:ital,wght@0,300;0,400;0,600;1,400&family=JetBrains+Mono:wght@400;500&display=swap');

/* ── Variables ── */
:root {
  --clr-bg:        #F5F2EE;
  --clr-bg-alt:    #EDEAE5;
  --clr-bg-dark:   #1C1C1C;
  --clr-panel:     #FFFFFF;
  --clr-text:      #1C1C1C;
  --clr-text-soft: #5A5651;
  --clr-orange:    #E05A00;
  --clr-orange-lt: #FF7722;
  --clr-steel:     #3F6B8C;
  --clr-steel-lt:  #6A9BBF;
  --clr-border:    #D4CECA;
  --clr-warn:      #FFE8D6;
  --clr-success:   #D6EDD6;
  --clr-danger:    #FDDEDE;

  --ff-head:  'Oswald', sans-serif;
  --ff-body:  'Source Serif 4', serif;
  --ff-mono:  'JetBrains Mono', monospace;

  --radius:   4px;
  --radius-lg:8px;
  --shadow:   0 2px 8px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
  --shadow-lg:0 8px 32px rgba(0,0,0,.12);

  --max-w:    860px;
  --max-w-lg: 1100px;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--clr-bg);
  color: var(--clr-text);
  font-family: var(--ff-body);
  font-size: 1.05rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--clr-steel); text-decoration: underline; text-underline-offset: 3px; }
a:hover { color: var(--clr-orange); }

/* ── Skip Link ── */
.skip-link {
  position: absolute; top: -999px; left: 8px;
  background: var(--clr-orange); color: #fff;
  padding: 6px 14px; border-radius: var(--radius);
  font-family: var(--ff-head); font-size: .85rem; letter-spacing: .05em;
  z-index: 9999;
}
.skip-link:focus { top: 8px; }

/* ── Site Header ── */
.site-header {
  background: var(--clr-bg-dark);
  color: #fff;
  border-bottom: 3px solid var(--clr-orange);
  position: sticky; top: 0; z-index: 100;
}
.header-inner {
  max-width: var(--max-w-lg);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: 60px;
}
.site-logo {
  font-family: var(--ff-head);
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: .03em;
  color: #fff;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
  white-space: nowrap;
}
.site-logo span { color: var(--clr-orange); }
.logo-icon { font-size: 1.4rem; }

/* ── Nav ── */
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  font-family: var(--ff-head);
  font-size: .82rem;
  font-weight: 500;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: #ccc;
  text-decoration: none;
  padding: 6px 10px;
  border-radius: var(--radius);
  transition: color .15s, background .15s;
}
.main-nav a:hover, .main-nav a.active {
  color: #fff;
  background: rgba(255,255,255,.1);
}
.main-nav a.nav-cta {
  background: var(--clr-orange);
  color: #fff;
  padding: 6px 14px;
}
.main-nav a.nav-cta:hover { background: var(--clr-orange-lt); }

/* Hamburger */
.nav-toggle {
  display: none;
  background: none; border: none;
  color: #fff; font-size: 1.5rem;
  cursor: pointer; padding: 4px;
}

/* ── Breadcrumb ── */
.breadcrumb {
  background: var(--clr-bg-alt);
  border-bottom: 1px solid var(--clr-border);
  font-size: .82rem;
  font-family: var(--ff-head);
  letter-spacing: .04em;
}
.breadcrumb-inner {
  max-width: var(--max-w-lg);
  margin: 0 auto;
  padding: 8px 24px;
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}
.breadcrumb a { color: var(--clr-text-soft); text-decoration: none; }
.breadcrumb a:hover { color: var(--clr-orange); }
.breadcrumb .sep { color: var(--clr-border); }
.breadcrumb .current { color: var(--clr-text); }

/* ── Hero ── */
.hero {
  background: var(--clr-bg-dark);
  color: #fff;
  padding: 72px 24px 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute; inset: 0;
  background: repeating-linear-gradient(
    -45deg,
    transparent,
    transparent 20px,
    rgba(224,90,0,.04) 20px,
    rgba(224,90,0,.04) 21px
  );
}
.hero-inner { position: relative; max-width: 720px; margin: 0 auto; }
.hero-eyebrow {
  font-family: var(--ff-mono);
  font-size: .78rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--clr-orange);
  margin-bottom: 16px;
  display: block;
}
.hero h1 {
  font-family: var(--ff-head);
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: .01em;
  margin-bottom: 20px;
}
.hero h1 em { color: var(--clr-orange); font-style: normal; }
.hero-sub {
  font-size: 1.1rem;
  color: #aaa;
  max-width: 560px;
  margin: 0 auto 32px;
  line-height: 1.65;
}
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--ff-head);
  font-size: .88rem;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 12px 24px;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s, transform .1s;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--clr-orange); color: #fff; border-color: var(--clr-orange); }
.btn-primary:hover { background: var(--clr-orange-lt); border-color: var(--clr-orange-lt); color: #fff; }
.btn-outline { background: transparent; color: #fff; border-color: rgba(255,255,255,.4); }
.btn-outline:hover { border-color: #fff; color: #fff; background: rgba(255,255,255,.08); }
.btn-steel { background: var(--clr-steel); color: #fff; border-color: var(--clr-steel); }
.btn-steel:hover { background: var(--clr-steel-lt); border-color: var(--clr-steel-lt); color: #fff; }
.btn-sm { padding: 8px 16px; font-size: .78rem; }

/* ── Alert / Warning Boxes ── */
.alert {
  border-left: 4px solid var(--clr-orange);
  background: var(--clr-warn);
  padding: 14px 18px;
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: .95rem;
  margin: 24px 0;
}
.alert strong { font-family: var(--ff-head); letter-spacing: .04em; font-size: 1rem; }
.alert-info { border-color: var(--clr-steel); background: #E8F0F7; }
.alert-success { border-color: #3A8C3A; background: var(--clr-success); }
.alert-danger { border-color: #C23B3B; background: var(--clr-danger); }

/* ── Stat Strip ── */
.stat-strip {
  background: var(--clr-orange);
  color: #fff;
  padding: 20px 24px;
}
.stat-strip-inner {
  max-width: var(--max-w-lg);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px;
  text-align: center;
}
.stat-item .num {
  font-family: var(--ff-head);
  font-size: 1.9rem;
  font-weight: 700;
  line-height: 1;
  display: block;
}
.stat-item .label {
  font-size: .8rem;
  font-family: var(--ff-mono);
  letter-spacing: .06em;
  opacity: .85;
}

/* ── Main Layout ── */
.page-wrap {
  max-width: var(--max-w-lg);
  margin: 0 auto;
  padding: 48px 24px 80px;
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 48px;
  align-items: start;
}
.page-wrap.full-width {
  grid-template-columns: 1fr;
  max-width: var(--max-w);
}
.page-content { min-width: 0; }

/* ── Typography ── */
h1, h2, h3, h4 {
  font-family: var(--ff-head);
  line-height: 1.2;
  letter-spacing: .01em;
  color: var(--clr-text);
}
h1 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); font-weight: 700; margin-bottom: 20px; }
h2 { font-size: clamp(1.3rem, 2.5vw, 1.75rem); font-weight: 600; margin: 40px 0 14px; padding-top: 8px; border-top: 2px solid var(--clr-border); }
h2:first-child { border-top: none; margin-top: 0; }
h3 { font-size: 1.15rem; font-weight: 600; margin: 28px 0 10px; color: var(--clr-steel); }
h4 { font-size: 1rem; font-weight: 600; margin: 20px 0 8px; }
p { margin-bottom: 18px; }
ul, ol { margin: 0 0 18px 24px; }
li { margin-bottom: 6px; }
strong { font-weight: 600; }
code {
  font-family: var(--ff-mono);
  background: var(--clr-bg-alt);
  padding: 2px 6px;
  border-radius: var(--radius);
  font-size: .88em;
  border: 1px solid var(--clr-border);
}

/* ── Tables ── */
.table-wrap { overflow-x: auto; margin: 24px 0; }
table { width: 100%; border-collapse: collapse; font-size: .95rem; }
thead th {
  background: var(--clr-bg-dark);
  color: #fff;
  font-family: var(--ff-head);
  font-weight: 500;
  letter-spacing: .05em;
  padding: 10px 14px;
  text-align: left;
}
tbody tr:nth-child(even) { background: var(--clr-bg-alt); }
tbody td { padding: 9px 14px; border-bottom: 1px solid var(--clr-border); vertical-align: top; }
.ok { color: #2A7A2A; font-weight: 600; }
.no { color: #C23B3B; font-weight: 600; }
.warn { color: #CC5500; font-weight: 600; }

/* ── Card Grid ── */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 20px;
  margin: 28px 0;
}
.card {
  background: var(--clr-panel);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 22px;
  text-decoration: none;
  color: var(--clr-text);
  box-shadow: var(--shadow);
  transition: box-shadow .2s, transform .2s, border-color .2s;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  border-color: var(--clr-orange);
  color: var(--clr-text);
}
.card-icon { font-size: 1.8rem; }
.card h3 {
  font-size: 1rem;
  margin: 0;
  color: var(--clr-text);
  border: none;
}
.card p { font-size: .88rem; color: var(--clr-text-soft); margin: 0; line-height: 1.5; }
.card .card-tag {
  font-family: var(--ff-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--clr-orange);
}

/* ── Sidebar ── */
.sidebar { position: sticky; top: 80px; display: flex; flex-direction: column; gap: 24px; }
.sidebar-box {
  background: var(--clr-panel);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 22px;
  box-shadow: var(--shadow);
}
.sidebar-box h4 {
  font-family: var(--ff-head);
  font-size: .85rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--clr-text-soft);
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--clr-border);
}
.sidebar-nav { list-style: none; margin: 0; padding: 0; }
.sidebar-nav li { margin: 0; }
.sidebar-nav a {
  display: block;
  font-size: .9rem;
  padding: 5px 0;
  color: var(--clr-text);
  text-decoration: none;
  border-bottom: 1px solid var(--clr-bg-alt);
  transition: color .15s, padding-left .15s;
}
.sidebar-nav a:hover { color: var(--clr-orange); padding-left: 4px; }

/* ── Tool Widget ── */
.tool-box {
  background: var(--clr-panel);
  border: 2px solid var(--clr-steel);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin: 32px 0;
  box-shadow: var(--shadow);
}
.tool-box h3 {
  font-size: 1.1rem;
  color: var(--clr-steel);
  margin: 0 0 6px;
  border: none;
}
.tool-box .tool-desc { font-size: .9rem; color: var(--clr-text-soft); margin-bottom: 20px; }
.form-row { margin-bottom: 16px; }
.form-row label {
  display: block;
  font-family: var(--ff-head);
  font-size: .82rem;
  letter-spacing: .05em;
  text-transform: uppercase;
  color: var(--clr-text-soft);
  margin-bottom: 6px;
}
.form-row input[type="number"],
.form-row select {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  font-family: var(--ff-body);
  font-size: 1rem;
  background: var(--clr-bg);
  color: var(--clr-text);
  transition: border-color .15s;
}
.form-row input:focus, .form-row select:focus {
  outline: none;
  border-color: var(--clr-steel);
  box-shadow: 0 0 0 3px rgba(63,107,140,.15);
}
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.tool-result {
  background: var(--clr-bg-alt);
  border-radius: var(--radius);
  padding: 18px;
  margin-top: 20px;
  display: none;
}
.tool-result.show { display: block; }
.tool-result .result-label {
  font-family: var(--ff-mono);
  font-size: .78rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--clr-text-soft);
  margin-bottom: 4px;
}
.tool-result .result-val {
  font-family: var(--ff-head);
  font-size: 2rem;
  font-weight: 700;
  color: var(--clr-text);
}
.tool-result .result-val.pass { color: #2A7A2A; }
.tool-result .result-val.fail { color: #C23B3B; }
.tool-result .result-msg { font-size: .92rem; margin-top: 8px; }

/* ── FAQ ── */
.faq { margin: 32px 0; }
.faq-item {
  border-bottom: 1px solid var(--clr-border);
}
.faq-q {
  width: 100%;
  background: none;
  border: none;
  text-align: left;
  padding: 16px 40px 16px 0;
  font-family: var(--ff-head);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: .02em;
  color: var(--clr-text);
  cursor: pointer;
  position: relative;
  line-height: 1.35;
}
.faq-q::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.4rem;
  color: var(--clr-orange);
  transition: transform .2s;
  font-weight: 400;
  font-family: var(--ff-head);
}
.faq-item.open .faq-q::after { transform: translateY(-50%) rotate(45deg); }
.faq-a {
  display: none;
  padding: 0 0 20px;
  font-size: .95rem;
  color: var(--clr-text-soft);
  line-height: 1.7;
}
.faq-item.open .faq-a { display: block; }

/* ── Download Box ── */
.download-box {
  background: linear-gradient(135deg, var(--clr-bg-dark) 0%, #2D2D2D 100%);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  align-items: center;
  gap: 20px;
  margin: 32px 0;
  flex-wrap: wrap;
}
.download-icon { font-size: 2.5rem; flex-shrink: 0; }
.download-text h4 { color: #fff; font-size: 1.1rem; margin: 0 0 4px; }
.download-text p { color: #aaa; font-size: .88rem; margin: 0; }
.download-box .btn { flex-shrink: 0; margin-left: auto; }

/* ── Footer ── */
.site-footer {
  background: var(--clr-bg-dark);
  color: #888;
  padding: 48px 24px 32px;
  border-top: 3px solid var(--clr-orange);
}
.footer-inner {
  max-width: var(--max-w-lg);
  margin: 0 auto;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .site-logo { font-size: 1.1rem; margin-bottom: 12px; }
.footer-brand p { font-size: .85rem; line-height: 1.6; color: #666; }
.footer-col h5 {
  font-family: var(--ff-head);
  font-size: .8rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: #aaa;
  margin-bottom: 14px;
}
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin-bottom: 6px; }
.footer-col a { color: #666; font-size: .88rem; text-decoration: none; transition: color .15s; }
.footer-col a:hover { color: var(--clr-orange); }
.footer-bottom {
  border-top: 1px solid #2A2A2A;
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: .82rem;
}
.footer-legal a { color: #555; text-decoration: none; margin-left: 16px; }
.footer-legal a:hover { color: var(--clr-orange); }
.disclaimer-footer {
  background: #222;
  border-top: 1px solid #2A2A2A;
  padding: 12px 24px;
  text-align: center;
  font-size: .78rem;
  color: #555;
  font-style: italic;
}

/* ── Section Dividers ── */
.section { padding: 56px 24px; }
.section-inner { max-width: var(--max-w-lg); margin: 0 auto; }
.section-alt { background: var(--clr-bg-alt); }
.section-dark { background: var(--clr-bg-dark); color: #fff; }
.section-dark h2, .section-dark h3 { color: #fff; }
.section-dark p { color: #aaa; }
.section-label {
  font-family: var(--ff-mono);
  font-size: .78rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--clr-orange);
  margin-bottom: 10px;
  display: block;
}
.section h2 { border-top: none; margin-top: 0; }

/* ── Tag Badges ── */
.tag {
  display: inline-block;
  font-family: var(--ff-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: var(--radius);
  background: var(--clr-bg-alt);
  color: var(--clr-text-soft);
  border: 1px solid var(--clr-border);
}
.tag-orange { background: #FFF0E6; color: var(--clr-orange); border-color: var(--clr-orange); }
.tag-steel { background: #E8F0F7; color: var(--clr-steel); border-color: var(--clr-steel); }
.tag-green { background: var(--clr-success); color: #2A7A2A; border-color: #2A7A2A; }
.tag-red { background: var(--clr-danger); color: #C23B3B; border-color: #C23B3B; }

/* ── Process Steps ── */
.steps { counter-reset: step; margin: 28px 0; }
.step {
  display: flex;
  gap: 20px;
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--clr-border);
}
.step:last-child { border-bottom: none; }
.step-num {
  counter-increment: step;
  flex-shrink: 0;
  width: 40px; height: 40px;
  background: var(--clr-orange);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--ff-head);
  font-weight: 700;
  font-size: 1rem;
}
.step-num::before { content: counter(step); }
.step-body h4 { margin-top: 6px; margin-bottom: 6px; }
.step-body p { margin: 0; font-size: .95rem; }

/* ── Code Rule Box ── */
.rule-box {
  background: var(--clr-bg-dark);
  color: #E0E0E0;
  border-radius: var(--radius-lg);
  padding: 22px 26px;
  margin: 24px 0;
  font-family: var(--ff-mono);
  font-size: .88rem;
  line-height: 1.8;
  border-left: 4px solid var(--clr-orange);
}
.rule-box .rule-cite {
  font-size: .72rem;
  letter-spacing: .08em;
  color: #666;
  display: block;
  margin-bottom: 8px;
}
.rule-box strong { color: var(--clr-orange); }

/* ── Responsive ── */
@media (max-width: 900px) {
  .page-wrap { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 680px) {
  .main-nav { display: none; flex-direction: column; position: absolute; top: 60px; left: 0; right: 0; background: var(--clr-bg-dark); padding: 16px 24px 24px; border-bottom: 3px solid var(--clr-orange); gap: 4px; }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 10px 12px; }
  .nav-toggle { display: block; }
  .hero { padding: 48px 20px 40px; }
  .form-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .download-box { flex-direction: column; }
  .download-box .btn { margin-left: 0; width: 100%; justify-content: center; }
  .stat-strip-inner { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 400px) {
  .header-inner { padding: 0 16px; }
  .site-logo { font-size: 1.1rem; }
}

/* ── Print ── */
@media print {
  .site-header, .site-footer, .sidebar, .breadcrumb { display: none; }
  .page-wrap { display: block; padding: 0; }
  body { font-size: 11pt; }
}

/* ── Analytics Placeholder ── */
/*
  GA4 placeholder — uncomment and replace G-XXXXXXXXXX after site is indexed:

  <script async src="https://www.googletagmanager.com/gtag/js?id=G-XXXXXXXXXX"></script>
  <script>
    window.dataLayer = window.dataLayer || [];
    function gtag(){dataLayer.push(arguments);}
    gtag('js', new Date());
    gtag('config', 'G-XXXXXXXXXX');
  </script>
*/