/* ===============================
   HowManyBTUs.com — main.css
   Palette: Teal primary + Orange CTA + Warm Slate text
   
   Primary:     #0f766e  (teal-700)
   Primary-dk:  #0d9488  (teal-600, hover)
   Primary-lt:  #f0fdfa  (teal-50, backgrounds)
   CTA:         #ea580c  (orange-600)
   CTA-dk:      #c2410c  (orange-700, hover)
   CTA-lt:      #fff7ed  (orange-50, subtle highlight)
   Body bg:     #f8fafc  (slate-50)
   Text:        #334155  (slate-700)
   Text-muted:  #64748b  (slate-500)
   Text-faint:  #94a3b8  (slate-400)
   Border:      #e2e8f0  (slate-200)
   Card bg:     #ffffff
================================ */

/* ===============================
   Base & Reset
================================ */

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: #f8fafc;
  color: #334155;
}

/* ===============================
   Layout
================================ */

.container {
  max-width: 520px;
  margin: 40px auto;
  padding: 0 20px;
}

main.container {
  margin-top: 20px;
}

/* ===============================
   Header (Ad-safe)
================================ */

.site-header {
  background: transparent;
  border-bottom: none;
  margin: 0;
  padding: 8px 0;
}

.header-ad-slot {
  min-height: 0;
  width: 100%;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.header-nav a {
  font-weight: 500;
  text-decoration: none;
}

.site-header img {
  height: 38px;
  width: auto;
  margin-right: 6px;
}

.site-nav a {
  font-weight: 500;
  text-decoration: none;
  opacity: 0.85;
}

.site-nav a:hover {
  text-decoration: underline;
  opacity: 1;
}

.site-nav {
  margin-left: auto;
}

.site-nav a {
  margin-left: 18px;
  font-size: 0.95rem;
  font-weight: 500;
}

/* ===============================
   Header spacing fix
================================ */

.site-header .container {
  margin: 0 auto;
  padding: 0;
}

/* ===============================
   Typography
================================ */

h1 {
  text-align: center;
  font-size: 2rem;
  color: #0f766e;
  margin-bottom: 10px;
}

h2 {
  color: #0f766e;
  margin-top: 40px;
  margin-bottom: 15px;
}

h3 {
  color: #0f766e;
  margin-top: 30px;
}

p {
  font-size: 1rem;
  line-height: 1.6;
  margin: 10px 0;
}

a {
  color: #0f766e;
}

a:hover {
  color: #0d9488;
}

.hint {
  margin-top: 8px;
  font-size: 0.85rem;
  color: #64748b;
  text-align: center;
  font-style: italic;
}

.hint a {
  color: #0f766e;
}

.intro {
  text-align: center;
  margin-bottom: 30px;
  color: #475569;
}

/* ===============================
   Forms & Inputs
================================ */

label {
  display: block;
  margin-bottom: 20px;
  font-weight: 600;
}

input[type="number"],
input[type="date"] {
  width: 100%;
  margin-top: 6px;
  padding: 12px;
  font-size: 1rem;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  background: #fff;
}

input:focus {
  outline: none;
  border-color: #0f766e;
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.1);
}

/* ===============================
   Select (Dropdowns)
================================ */

select {
  width: 100%;
  margin-top: 6px;
  padding: 12px 40px 12px 12px;
  font-size: 1rem;
  font-family: inherit;
  color: #334155;
  background-color: #fff;
  border: 1px solid #cbd5e1;
  border-radius: 8px;

  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;

  background-image:
    linear-gradient(45deg, transparent 50%, #64748b 50%),
    linear-gradient(135deg, #64748b 50%, transparent 50%);
  background-position:
    calc(100% - 22px) calc(50% - 3px),
    calc(100% - 16px) calc(50% - 3px);
  background-size:
    6px 6px,
    6px 6px;
  background-repeat: no-repeat;
}

select:focus {
  outline: none;
  border-color: #0f766e;
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.1);
}

select:disabled {
  background-color: #f1f5f9;
  color: #94a3b8;
  cursor: not-allowed;
}

label select {
  margin-top: 6px;
}

/* ===============================
   Hub & Cross-Navigation Links
================================ */

.hub-link {
  margin: 18px 0 28px;
  font-size: 0.95rem;
  color: #475569;
  text-align: center;
}

.hub-link a {
  font-weight: 600;
  color: #0f766e;
  text-decoration: none;
}

.hub-link a:hover {
  text-decoration: underline;
  color: #0d9488;
}

/* ===============================
   Results Box
================================ */

.result {
  margin-top: 25px;
  padding: 20px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
  font-size: 1.05rem;
}

.result p {
  margin: 8px 0;
}

/* ===============================
   Tool List (Homepage)
================================ */

.tools {
  margin-top: 40px;
}

.tool-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.tool-list li {
  background: #fff;
  border-radius: 10px;
  margin-bottom: 15px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
}

.tool-list a {
  display: block;
  padding: 16px;
  color: inherit;
  text-decoration: none;
}

.tool-list a:hover {
  background: #f0fdfa;
}

/* ===============================
   Equipment List (compact catalog)
   Use instead of .tool-list on pages with
   many product/affiliate links (50+).
   Flat rows with inline links instead of cards.
================================ */

.equipment-list {
  list-style: none;
  padding: 0;
  margin: 0 0 16px;
}

.equipment-list li {
  padding: 7px 0;
  border-bottom: 1px solid #e2e8f0;
  font-size: 0.95rem;
  line-height: 1.55;
}

.equipment-list li:last-child {
  border-bottom: none;
}

.equipment-list a {
  color: #0f766e;
  text-decoration: none;
  font-weight: 600;
}

.equipment-list a:hover {
  color: #ea580c;
  text-decoration: underline;
}

.equipment-list .eq-desc {
  color: #64748b;
  font-weight: 400;
}

.equipment-list .eq-browse {
  display: inline-block;
  margin-top: 4px;
  padding: 3px 10px;
  background: #f0fdfa;
  border-radius: 5px;
  font-size: 0.9rem;
}

/* ===============================
   Footer
================================ */

.site-footer {
  background: transparent;
  border-top: none;
  margin-top: 40px;
}

.site-footer .container {
  text-align: center;
  padding: 10px 0;
}

.footer-links {
  font-size: 0.8rem;
  color: #94a3b8;
  margin-bottom: 6px;
  line-height: 1.5;
}

.footer-links a {
  color: #64748b;
  text-decoration: none;
}

.footer-links a:hover {
  text-decoration: underline;
}

.footer-copy {
  font-size: 0.75rem;
  color: #94a3b8;
  margin: 0;
}

/* ===============================
   Mobile
================================ */

@media (max-width: 400px) {
  .container {
    margin: 25px auto;
    padding: 0 15px;
  }

  h1 {
    font-size: 1.6rem;
  }
}

/* ===============================
   Mobile Header
================================ */

@media (max-width: 480px) {

  .header-inner {
    padding: 6px 0;
  }

  .site-header img {
    height: 32px;
  }
}

/* =========================
   Tool list grouping labels
   ========================= */

.tool-group {
  list-style: none;
  margin-top: 1.5rem;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  opacity: 0.6;
}

.tool-group + li {
  margin-top: 0.25rem;
}

.related-calculators {
  margin-top: 2.5rem;
  font-size: 0.9rem;
  color: #64748b;
}

.related-calculators a {
  font-weight: 500;
}

/* ===============================
   Homepage Enhancements
   =============================== */

.hero {
  margin-bottom: 35px;
}

.hero h1 {
  margin-bottom: 12px;
}

.hero .intro {
  font-size: 1.05rem;
}

/* ===============================
   Category Hub
   =============================== */

.categories {
  margin-top: 40px;
}

.category-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.category-card {
  display: block;
  background: #fff;
  border-radius: 10px;
  padding: 16px;
  text-decoration: none;
  color: inherit;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
}

.category-card:hover {
  background: #f0fdfa;
}

.category-card h3 {
  margin-top: 0;
  margin-bottom: 6px;
  font-size: 1.1rem;
}

.category-card p {
  margin: 0;
  font-size: 0.95rem;
  color: #64748b;
}

/* ===============================
   Popular Tools
   =============================== */

.popular-tools {
  margin-top: 45px;
}

.popular-tools .tool-list li {
  margin-bottom: 10px;
}

/* ===============================
   Authority Content
   =============================== */

.authority {
  margin-top: 45px;
  font-size: 0.95rem;
  color: #475569;
}

.authority p {
  margin-bottom: 12px;
}

.authority a {
  font-weight: 500;
}

/* ===============================
   Supplies / Equipment Callout Box
   =============================== */

.supplies-callout {
  background: #f0fdfa;
  padding: 20px 24px;
  border-radius: 8px;
  margin: 30px 0;
  border-left: 4px solid #0f766e;
}

.supplies-callout h2 {
  margin-top: 0;
  font-size: 1.3rem;
}

.supplies-callout p {
  margin-bottom: 16px;
}

.supplies-callout p:last-child {
  margin-bottom: 0;
}

/* Affiliate links inside callout: inherit teal, but orange on hover for action signal */
.supplies-callout a {
  color: #0f766e;
  font-weight: 600;
}

.supplies-callout a:hover {
  color: #ea580c;
}

/* ===============================
   FAQ Section
   =============================== */

.faq {
  margin-top: 45px;
}

.faq h3 {
  margin-top: 22px;
  margin-bottom: 6px;
  font-size: 1rem;
}

.faq p {
  margin-top: 0;
  font-size: 0.95rem;
  color: #475569;
}

/* ===============================
   Comparison Tables (SEO)
================================ */

table {
  width: 100%;
  border-collapse: collapse;
  margin: 25px 0;
  font-size: 0.95rem;
  background: #fff;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
}

thead {
  background: #f0fdfa;
}

th,
td {
  padding: 12px 14px;
  text-align: left;
}

th {
  font-weight: 600;
  color: #0f766e;
}

/* Affiliate links in table cells */
td a {
  color: #0f766e;
  font-weight: 600;
  text-decoration: none;
}

td a:hover {
  color: #ea580c;
  text-decoration: underline;
}

tbody tr:not(:last-child) {
  border-bottom: 1px solid #e2e8f0;
}

tbody tr strong {
  color: #1e293b;
}

@media (max-width: 480px) {
  table {
    font-size: 0.9rem;
  }
}

/* ===============================
   Tooltip (calculator hints)
================================ */

.tooltip {
  position: relative;
  display: inline-block;
  margin-left: 4px;
  cursor: help;
  font-size: 0.9em;
  opacity: 0.7;
}

.tooltip:hover {
  opacity: 1;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  left: 50%;
  bottom: 125%;
  transform: translateX(-50%);
  min-width: 220px;
  max-width: 280px;
  padding: 8px 10px;
  background: #1e293b;
  color: #fff;
  font-size: 0.85rem;
  line-height: 1.4;
  border-radius: 6px;
  white-space: normal;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
  z-index: 10;
}

.tooltip::before {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 115%;
  transform: translateX(-50%);
  border-width: 6px;
  border-style: solid;
  border-color: #1e293b transparent transparent transparent;
  opacity: 0;
  transition: opacity 0.15s ease;
}

.tooltip:hover::after,
.tooltip:hover::before {
  opacity: 1;
}

/* ===============================
   Primary Tool Highlight Box
   =============================== */

.primary-tool {
  margin: 1.75rem 0 2rem;
  padding: 1.25rem 1.5rem;
  border: 1px solid #e2e8f0;
  border-left: 4px solid #0f766e;
  background-color: #f8fafc;
  border-radius: 6px;
}

.primary-tool__label {
  display: block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #64748b;
  margin-bottom: 0.35rem;
}

.primary-tool__title {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
  line-height: 1.35;
}

.primary-tool__title a {
  color: #1e293b;
  text-decoration: none;
}

.primary-tool__title a:hover {
  text-decoration: underline;
}

.primary-tool__description {
  font-size: 0.9rem;
  color: #475569;
  margin: 0;
}

.primary-tool + section {
  margin-top: 2.5rem;
}

/* ===============================
   Calculator Teaser
================================ */

.calculator-teaser {
  margin: 40px 0;
  padding: 20px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.06);
}

.calculator-teaser h2 {
  font-size: 1.5rem;
  margin-bottom: 12px;
  color: #0f766e;
  text-align: center;
}

.calculator-teaser p {
  text-align: center;
  font-size: 0.95rem;
  color: #475569;
  margin-bottom: 20px;
}

.calculator-teaser .calculator-form {
  display: grid;
  gap: 16px;
}

.calculator-teaser .calculator-form label {
  margin-bottom: 0;
  font-weight: 600;
  font-size: 0.95rem;
}

.calculator-teaser .calculator-form input[type="number"] {
  padding: 10px 12px;
  font-size: 1rem;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  width: 100%;
}

.calculator-teaser .teaser-result {
  margin-top: 20px;
  padding: 16px;
  background: #f8fafc;
  border-radius: 10px;
  box-shadow: inset 0 1px 3px rgba(0,0,0,0.05);
  font-size: 0.95rem;
}

.calculator-teaser .teaser-result p {
  margin: 6px 0;
  line-height: 1.4;
}

.calculator-teaser .teaser-result strong {
  color: #1e293b;
}

@media (max-width: 480px) {
  .calculator-teaser {
    padding: 16px;
  }

  .calculator-teaser h2 {
    font-size: 1.3rem;
  }

  .calculator-teaser p {
    font-size: 0.9rem;
  }

  .calculator-teaser .calculator-form input[type="number"] {
    font-size: 0.95rem;
    padding: 8px 10px;
  }
}

/* ===============================
   Buttons
   Primary = Orange (CTA / action / affiliate)
   Secondary = Teal-tinted (navigation / lower priority)
================================ */

.btn-primary {
  display: inline-block;
  padding: 12px 22px;
  background-color: #ea580c;
  color: #fff;
  font-weight: 600;
  text-decoration: none;
  border-radius: 6px;
  transition: background 0.2s;
}

.btn-primary:hover {
  background-color: #c2410c;
  color: #fff;
}

.btn-secondary {
  display: inline-block;
  padding: 10px 20px;
  background-color: #f0fdfa;
  color: #0f766e;
  font-weight: 600;
  text-decoration: none;
  border-radius: 6px;
  transition: background 0.2s;
}

.btn-secondary:hover {
  background-color: #ccfbf1;
  color: #0f766e;
}

/* ===============================
   Calculator breakdown toggle
================================ */

.calc-toggle {
  border: none;
  cursor: pointer;
}

.calc-breakdown {
  margin-top: 10px;
  padding: 12px;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  background: #f8fafc;
}

.calc-breakdown .muted {
  color: #64748b;
  font-weight: 500;
  font-size: 0.95rem;
}

/* ===============================
   Call-to-Action Wrappers
=============================== */

.hero-cta {
  text-align: center;
  margin-top: 20px;
}

.calculator-teaser-cta,
.calculator-cta {
  text-align: center;
  margin: 18px 0 28px;
}

.guide-cta {
  text-align: center;
  margin: 18px 0 28px;
}

.faq-cta {
  text-align: center;
  margin: 18px 0 28px;
}

/* ===============================
   Lead Capture / Email Form
================================ */

.lead-capture {
  margin-top: 30px;
  padding: 20px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
}

.lead-capture form {
  display: grid;
  gap: 16px;
}

.lead-capture label {
  font-weight: 600;
  font-size: 0.95rem;
}

.lead-capture input[type="text"],
.lead-capture input[type="email"] {
  padding: 12px;
  font-size: 1rem;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  width: 100%;
}

.lead-capture button {
  display: inline-block;
  padding: 12px 22px;
  font-weight: 600;
  border-radius: 6px;
  border: none;
  background-color: #ea580c;
  color: #fff;
  cursor: pointer;
  transition: background 0.2s;
}

.lead-capture button:hover {
  background-color: #c2410c;
}

/* ===============================
   Download Report Form Spacing
================================ */

#downloadReportForm label {
  display: block;
  margin-bottom: 6px;
  font-weight: 600;
}

#downloadReportForm input {
  display: block;
  width: 100%;
  padding: 12px;
  margin-bottom: 16px;
  font-size: 1rem;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
}

#downloadReportForm button {
  margin-top: 10px;
}

/* ===============================
   Calculator Form (shared)
================================ */

.calculator-form {
  display: grid;
  gap: 16px;
}

.calculator-form label {
  margin: 0;
  font-weight: 600;
  font-size: 0.95rem;
}

.calculator-form input[type="text"],
.calculator-form input[type="email"],
.calculator-form input[type="number"],
.calculator-form input[type="date"] {
  width: 100%;
  margin-top: 6px;
  padding: 12px;
  font-size: 1rem;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  background: #fff;
}

.calculator-form input:focus,
.calculator-form select:focus {
  outline: none;
  border-color: #0f766e;
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.1);
}

/* Result container */
.calculator-result {
  margin-top: 14px;
  padding: 20px;
  background: #fff;
  border-radius: 10px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.05);
  font-size: 1.05rem;
}

.calculator-result p {
  margin: 8px 0;
}

/* Generic muted helper */
.muted {
  color: #64748b;
  font-weight: 500;
  font-size: 0.95rem;
}

.calculator-form label input[type="checkbox"] {
  margin: 0;
}

/* ===============================
   Quick Start Box
   =============================== */

.quick-start-box {
  margin: 28px 0 35px;
  padding: 16px 20px;
  background: linear-gradient(135deg, #f0fdfa 0%, #ccfbf1 100%);
  border-left: 4px solid #0f766e;
  border-radius: 10px;
}

.quick-start-label {
  margin: 0 0 6px 0;
  font-size: 0.9rem;
  font-weight: 600;
  color: #134e4a;
}

.quick-start-text {
  margin: 0 0 8px 0;
  font-size: 0.95rem;
  color: #134e4a;
  line-height: 1.5;
}

.quick-start-text:last-child {
  margin-bottom: 0;
}

.quick-start-text a {
  color: #0f766e;
  font-weight: 600;
  text-decoration: underline;
}

.quick-start-text a:hover {
  color: #ea580c;
}

/* ===============================
   Section Headers
   =============================== */

.calculators-section {
  margin-top: 45px;
}

.section-heading {
  font-size: 1.5rem;
  color: #0f766e;
  margin: 0 0 6px 0;
  text-align: center;
}

.section-intro {
  text-align: center;
  color: #64748b;
  font-size: 0.95rem;
  margin: 0 0 22px 0;
}

/* ===============================
   Calculator Card Grid
   =============================== */

.calculator-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-bottom: 20px;
}

@media (min-width: 640px) {
  .calculator-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ===============================
   Calculator Cards
   =============================== */

.calc-card {
  display: block;
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 20px;
  text-decoration: none;
  color: inherit;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  transition: all 0.2s ease;
  position: relative;
}

.calc-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.08);
  border-color: #0f766e;
}

.calc-card__icon {
  font-size: 2rem;
  margin-bottom: 10px;
  line-height: 1;
}

.calc-card__title {
  font-size: 1.1rem;
  font-weight: 700;
  color: #0f766e;
  margin: 0 0 8px 0;
}

.calc-card__desc {
  font-size: 0.9rem;
  color: #475569;
  margin: 0;
  line-height: 1.5;
}

.calc-card__tag {
  display: inline-block;
  margin-top: 10px;
  padding: 4px 10px;
  background: #f0fdfa;
  color: #0f766e;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* Primary card variant (advanced calculator, featured) */
.calc-card--primary {
  background: linear-gradient(135deg, #f0fdfa 0%, #ccfbf1 100%);
  border-color: #0f766e;
  border-width: 2px;
}

.calc-card--primary:hover {
  border-color: #0d9488;
}

/* Urgent card variant (seasonal, limited) */
.calc-card--urgent {
  background: linear-gradient(135deg, #fff7ed 0%, #fed7aa 100%);
  border-color: #ea580c;
  border-width: 2px;
}

.calc-card--urgent:hover {
  border-color: #c2410c;
}

.calc-card__tag--urgent {
  background: #fff7ed;
  color: #9a3412;
}

/* ===============================
   Tips Section
   =============================== */

.tips-section {
  margin-top: 45px;
}

.tips-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 20px;
}

@media (min-width: 640px) {
  .tips-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.tip-card {
  background: #fff;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  padding: 18px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.03);
}

.tip-card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: #0f766e;
  margin: 0 0 8px 0;
}

.tip-card p {
  font-size: 0.9rem;
  color: #475569;
  margin: 0;
  line-height: 1.5;
}

/* ===============================
   Mobile optimizations
   =============================== */

@media (max-width: 480px) {
  .quick-start-box {
    padding: 14px 16px;
  }

  .section-heading {
    font-size: 1.3rem;
  }

  .calc-card {
    padding: 16px;
  }

  .calc-card__title {
    font-size: 1rem;
  }

  .calc-card__desc {
    font-size: 0.85rem;
  }
}

/* ===============================
   Inline affiliate link style
   Affiliate links in body text: teal by default, 
   orange on hover to signal "this goes somewhere external"
================================ */

a[href^="/go/"] {
  color: #0f766e;
  font-weight: 600;
  text-decoration: none;
}

a[href^="/go/"]:hover {
  color: #ea580c;
  text-decoration: underline;
}