/* ==========================================
   WattCosts Design System
   "Utility Dashboard" aesthetic
   ========================================== */

/* --- CSS Custom Properties --- */
:root {
  --color-primary: #1B6B4A;
  --color-primary-dark: #134F36;
  --color-primary-light: #E8F5EE;
  --color-accent: #F5A623;
  --color-accent-light: #FFF8EC;
  --color-bg: #FAFBFC;
  --color-surface: #FFFFFF;
  --color-text: #1A2332;
  --color-text-muted: #6B7A8D;
  --color-border: #E2E8F0;
  --color-saving: #16A34A;
  --color-expensive: #DC2626;

  --font-display: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 50px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.1);

  --max-width: 1120px;
  --content-width: 740px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.65;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--color-primary-dark);
}

/* --- Accessibility --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  background: var(--color-primary);
  color: #fff;
  padding: 0.75rem 1.5rem;
  z-index: 1000;
  font-weight: 600;
  font-family: var(--font-body);
  border-radius: 0 0 var(--radius-sm) 0;
}

.skip-link:focus {
  top: 0;
}

:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* --- Typography --- */
h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
}

h1 {
  font-size: 2.25rem;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

h2 {
  font-size: 1.625rem;
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
}

h3 {
  font-size: 1.25rem;
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

h4 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

p {
  margin-bottom: 1rem;
}

/* --- Navigation --- */
.site-nav {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.logo-icon {
  flex-shrink: 0;
}

.logo-text {
  font-family: var(--font-display);
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--color-text);
}

.logo-accent {
  color: var(--color-primary);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  min-width: 44px;
  min-height: 44px;
}

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

.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);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 0.5rem 1rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  transition: color 0.15s ease, background 0.15s ease;
}

.nav-links a:hover {
  color: var(--color-text);
  background: var(--color-bg);
}

/* --- Main Content --- */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

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

/* --- Cards --- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
}

.card-highlight {
  border-color: var(--color-primary);
  border-width: 2px;
}

/* --- Calculator Components --- */
.calculator-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  margin-bottom: 2rem;
}

.calculator-card h2 {
  margin-top: 0;
  font-size: 1.25rem;
}

.form-group {
  margin-bottom: 1.25rem;
}

.form-group label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: 0.375rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 0.75rem 1rem;
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-text);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  min-height: 44px;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(27, 107, 74, 0.12);
  outline: none;
}

.form-group .input-with-unit {
  position: relative;
}

.form-group .input-unit {
  position: absolute;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  pointer-events: none;
}

.form-group .input-with-unit input {
  padding-right: 4rem;
}

/* --- Results Display --- */
.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.result-item {
  background: var(--color-bg);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  text-align: center;
}

.result-label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 0.25rem;
}

.result-value {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-text);
}

.result-value.cost-highlight {
  color: var(--color-primary);
}

.result-sub {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-top: 0.25rem;
}

/* --- Quick Answer Box --- */
.quick-answer {
  background: var(--color-primary-light);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
}

.quick-answer p {
  margin: 0;
  font-size: 1.0625rem;
}

.quick-answer strong {
  font-family: var(--font-display);
  font-weight: 700;
}

/* --- Trust Bar --- */
.trust-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  padding: 1rem 0;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.trust-item svg {
  flex-shrink: 0;
  color: var(--color-primary);
}

/* --- State Badge --- */
.state-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  background: var(--color-accent-light);
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-pill);
  padding: 0.375rem 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text);
}

.state-badge .rate {
  font-family: var(--font-mono);
}

/* --- Tip Box --- */
.tip-box {
  background: var(--color-accent-light);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin: 1.5rem 0;
}

.tip-box h3 {
  margin-top: 0;
  color: var(--color-text);
  font-size: 1rem;
}

.tip-box ul {
  padding-left: 1.25rem;
  margin: 0;
}

.tip-box li {
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

.tip-box li:last-child {
  margin-bottom: 0;
}

/* --- Comparison Table --- */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9375rem;
}

.comparison-table th,
.comparison-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.comparison-table th {
  font-weight: 600;
  color: var(--color-text-muted);
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--color-bg);
}

.comparison-table td {
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.comparison-table tr:last-child td {
  border-bottom: none;
}

/* --- Cost Indicators --- */
.cost-cheap {
  color: var(--color-saving);
  font-weight: 600;
}

.cost-moderate {
  color: var(--color-accent);
  font-weight: 600;
}

.cost-expensive {
  color: var(--color-expensive);
  font-weight: 600;
}

/* --- Breadcrumbs --- */
.breadcrumb {
  margin-bottom: 1.5rem;
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  font-size: 0.875rem;
  gap: 0.25rem;
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  color: var(--color-text-muted);
}

.breadcrumb li:not(:last-child)::after {
  content: "›";
  color: var(--color-text-muted);
  margin-left: 0.25rem;
}

.breadcrumb a {
  color: var(--color-text-muted);
}

.breadcrumb a:hover {
  color: var(--color-primary);
}

.breadcrumb [aria-current="page"] {
  color: var(--color-text);
  font-weight: 500;
}

/* --- FAQ Section --- */
.faq-section {
  margin-top: 3rem;
}

.faq-item {
  border-bottom: 1px solid var(--color-border);
}

.faq-item:first-of-type {
  border-top: 1px solid var(--color-border);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 1.25rem 0;
  background: none;
  border: none;
  font-family: var(--font-body);
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-text);
  text-align: left;
  cursor: pointer;
  min-height: 44px;
}

.faq-question::after {
  content: "+";
  font-size: 1.25rem;
  font-weight: 400;
  color: var(--color-text-muted);
  flex-shrink: 0;
  margin-left: 1rem;
  transition: transform 0.2s ease;
}

.faq-question[aria-expanded="true"]::after {
  content: "−";
}

.faq-answer {
  display: none;
  padding-bottom: 1.25rem;
  color: var(--color-text);
  line-height: 1.7;
}

.faq-answer.open {
  display: block;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: background 0.15s ease, transform 0.1s ease;
  min-height: 44px;
  min-width: 44px;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

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

.btn-secondary {
  background: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-border);
}

/* --- Tool Grid (Homepage) --- */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
  margin: 2rem 0;
}

.tool-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  text-decoration: none;
  color: var(--color-text);
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.tool-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary);
  color: var(--color-text);
}

.tool-card h3 {
  margin-top: 0.75rem;
  margin-bottom: 0.375rem;
  font-size: 1.125rem;
}

.tool-card p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin: 0;
}

/* --- Category Cards --- */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}

.category-card {
  display: flex;
  align-items: center;
  gap: 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  text-decoration: none;
  color: var(--color-text);
  transition: box-shadow 0.15s ease;
}

.category-card:hover {
  box-shadow: var(--shadow-sm);
  color: var(--color-text);
}

/* --- Disclaimer --- */
.disclaimer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-text);
  color: #fff;
  padding: 3rem 0 2rem;
  margin-top: 4rem;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.footer-brand {
  margin-bottom: 2rem;
}

.footer-logo {
  text-decoration: none;
}

.footer-logo .logo-text {
  color: #fff;
  font-size: 1.25rem;
}

.footer-logo .logo-accent {
  color: var(--color-accent);
}

.footer-tagline {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.875rem;
  margin-top: 0.25rem;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 2rem;
  margin-bottom: 2.5rem;
}

.footer-col h4 {
  font-family: var(--font-display);
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 0.75rem;
}

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

.footer-col li {
  margin-bottom: 0.5rem;
}

.footer-col a {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.9375rem;
  transition: color 0.15s ease;
}

.footer-col a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 1.5rem;
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.4);
}

.footer-bottom p {
  margin-bottom: 0.25rem;
}

.footer-source a {
  color: rgba(255, 255, 255, 0.5);
}

.footer-source a:hover {
  color: rgba(255, 255, 255, 0.8);
}

/* --- Content Sections --- */
.section-header {
  margin-bottom: 1.5rem;
}

.section-header p {
  color: var(--color-text-muted);
  font-size: 1.0625rem;
}

/* --- Hero --- */
.hero {
  text-align: center;
  padding: 3rem 0 2rem;
}

.hero h1 {
  font-size: 2.75rem;
  max-width: 640px;
  margin: 0 auto 1rem;
}

.hero p {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  max-width: 520px;
  margin: 0 auto 2rem;
}

/* --- Blog / Article --- */
article.content-narrow h2 {
  margin-top: 2.5rem;
}

article.content-narrow h3 {
  margin-top: 2rem;
}

article.content-narrow ul,
article.content-narrow ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

article.content-narrow li {
  margin-bottom: 0.5rem;
  line-height: 1.65;
}

article.content-narrow a {
  text-decoration: underline;
  text-decoration-color: var(--color-primary-light);
  text-underline-offset: 2px;
}

article.content-narrow a:hover {
  text-decoration-color: var(--color-primary);
}

/* --- Utility --- */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

/* --- Mobile Responsive (768px) --- */
@media (max-width: 768px) {
  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.375rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: 0.5rem 1.5rem 1rem;
    box-shadow: var(--shadow-md);
  }

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

  .nav-links a {
    padding: 0.75rem 0;
  }

  .results-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .result-value {
    font-size: 1.5rem;
  }

  .calculator-card {
    padding: 1.5rem;
  }

  .tool-grid {
    grid-template-columns: 1fr;
  }

  .footer-links {
    grid-template-columns: 1fr 1fr;
  }

  main {
    padding: 1.5rem 1rem 3rem;
  }

  .trust-bar {
    gap: 1rem;
  }
}

@media (max-width: 480px) {
  .results-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
  }

  .result-item {
    padding: 1rem;
  }

  .footer-links {
    grid-template-columns: 1fr;
  }
}