/* GHG professional site — RSK-inspired structure, distinct GreenCarbon palette */

:root {
  --font-sans: "Inter", system-ui, sans-serif;
  --font-serif: "Source Serif 4", Georgia, serif;
  --shadow-sm: 0 1px 2px rgba(26, 31, 28, 0.06);
  --shadow-md: 0 12px 40px rgba(26, 31, 28, 0.08);
  --radius: 4px;
  --header-h: 4rem;
  --max: 72rem;
}

html[data-theme="light"] {
  --color-bg: #f4f8f5;
  --color-surface: #ffffff;
  --color-text: #0d3b2b;
  --color-muted: #3a6a50;
  --color-border: rgba(13, 59, 43, 0.15);
  --color-accent: #1a6b47;
  --color-accent-hover: #0d4f3c;
  --color-accent-soft: #e8f2ee;
}

html[data-theme="dark"] {
  --color-bg: #050e08;
  --color-surface: #071a10;
  --color-text: #f4f9f6;
  --color-muted: rgba(255, 255, 255, 0.72);
  --color-border: rgba(46, 139, 87, 0.22);
  --color-accent: #2e8b57;
  --color-accent-hover: #4caf72;
  --color-accent-soft: rgba(0, 191, 165, 0.2);
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  transition: background 0.35s ease, color 0.35s ease;
}

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

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

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

.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;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  z-index: 200;
  padding: 0.5rem 1rem;
  background: var(--color-accent);
  color: #fff;
  font-weight: 600;
  border-radius: var(--radius);
}

.skip-link:focus {
  top: 1rem;
}

.container {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

.container.narrow {
  max-width: 42rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--color-surface) 92%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
  min-height: var(--header-h);
}

.logo {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.nav-toggle-bar,
.nav-toggle-bar::before,
.nav-toggle-bar::after {
  display: block;
  width: 1.5rem;
  height: 2px;
  background: var(--color-text);
  border-radius: 1px;
}

.nav-toggle-bar {
  position: relative;
}

.nav-toggle-bar::before,
.nav-toggle-bar::after {
  content: "";
  position: absolute;
  left: 0;
}

.nav-toggle-bar::before {
  top: -7px;
}

.nav-toggle-bar::after {
  top: 7px;
}

.site-header.nav-open .nav-toggle-bar {
  background: transparent;
}

.site-header.nav-open .nav-toggle-bar::before {
  top: 0;
  transform: rotate(45deg);
}

.site-header.nav-open .nav-toggle-bar::after {
  top: 0;
  transform: rotate(-45deg);
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 1.75rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-list a {
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--color-text);
  text-decoration: none;
}

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

.nav-cta {
  padding: 0.5rem 1rem;
  background: var(--color-accent);
  color: #fff !important;
  border-radius: var(--radius);
}

.nav-cta:hover {
  background: var(--color-accent-hover);
  color: #fff !important;
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 1rem;
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.2s ease, opacity 0.2s ease, visibility 0.2s;
  }

  .site-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-list li {
    border-bottom: 1px solid var(--color-border);
  }

  .nav-list a {
    display: block;
    padding: 0.875rem 0;
  }

  .nav-cta {
    margin-top: 0.5rem;
    text-align: center;
  }
}

/* Hero */
.hero {
  position: relative;
  min-height: min(78vh, 36rem);
  display: flex;
  align-items: flex-end;
  padding: 4rem 0 3.5rem;
  overflow: hidden;
}

.hero-media {
  position: absolute;
  inset: 0;
  background: #1a2420;
}

.hero-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero-scrim {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(
    105deg,
    rgba(13, 79, 60, 0.88) 0%,
    rgba(13, 79, 60, 0.72) 42%,
    rgba(26, 31, 28, 0.62) 100%
  );
  pointer-events: none;
}

@media (prefers-reduced-motion: reduce) {
  .hero-video {
    display: none;
  }

  .hero-media {
    background-image:
      linear-gradient(
        105deg,
        rgba(13, 79, 60, 0.88) 0%,
        rgba(13, 79, 60, 0.72) 42%,
        rgba(26, 31, 28, 0.62) 100%
      ),
      url("https://images.unsplash.com/photo-1500382017468-9049fed747ef?w=1600&q=80");
    background-size: cover;
    background-position: center;
  }
}

.hero-content {
  position: relative;
  z-index: 2;
  color: #fff;
  max-width: 40rem;
}

.hero .eyebrow {
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  opacity: 0.9;
  margin: 0 0 0.75rem;
}

.hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 2.85rem);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 1rem;
  letter-spacing: -0.02em;
}

.hero .lead {
  font-size: 1.0625rem;
  line-height: 1.65;
  opacity: 0.95;
  margin: 0 0 1.75rem;
  max-width: 36rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.35rem;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

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

.btn-primary:hover {
  background: var(--color-accent-soft);
  color: var(--color-accent-hover);
  border-color: var(--color-accent-soft);
}

.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.55);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: #fff;
  color: #fff;
}

/* Promo trio — RSK-style three columns */
.promo-trio {
  margin-top: -2.5rem;
  position: relative;
  z-index: 2;
  padding-bottom: 1rem;
}

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

@media (max-width: 900px) {
  .promo-grid {
    grid-template-columns: 1fr;
  }

  .promo-trio {
    margin-top: 1.5rem;
  }
}

.promo-card {
  display: flex;
  flex-direction: column;
  padding: 1.75rem 1.5rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 2px;
  box-shadow: var(--shadow-md);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.promo-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 16px 48px rgba(13, 79, 60, 0.12);
}

.promo-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.5rem;
}

.promo-card h2 {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 600;
  margin: 0 0 auto;
  padding-bottom: 1rem;
  line-height: 1.3;
}

.promo-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-accent);
}

.promo-card:hover .promo-link {
  text-decoration: underline;
}

/* Sections */
.section {
  padding: 4rem 0;
}

.section-alt {
  background: var(--color-surface);
  border-block: 1px solid var(--color-border);
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.65rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
}

.section-header {
  margin-bottom: 2rem;
  max-width: 36rem;
}

.section-intro {
  margin: 0;
  color: var(--color-muted);
  font-size: 1.0625rem;
}

.statement p {
  font-size: 1.0625rem;
  color: var(--color-muted);
  margin: 0 0 1rem;
}

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

/* Grids */
.card-grid {
  display: grid;
  gap: 1.25rem;
}

.card-grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

.card-grid-6 {
  grid-template-columns: repeat(3, 1fr);
}

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

@media (max-width: 900px) {
  .card-grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .card-grid-6 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 560px) {
  .card-grid-4,
  .card-grid-6,
  .card-grid-2 {
    grid-template-columns: 1fr;
  }
}

.tile,
.feature-card {
  padding: 1.5rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 2px;
}

.section-alt .tile,
.section-alt .feature-card {
  background: var(--color-surface);
}

.tile h3,
.feature-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin: 0 0 0.5rem;
}

.tile p,
.feature-card p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--color-muted);
}

.credential-list {
  margin: 0;
  padding-left: 1.25rem;
  max-width: 40rem;
}

.credential-list li {
  margin-bottom: 0.75rem;
  padding-left: 0.25rem;
}

.credential-list li:last-child {
  margin-bottom: 0;
}

/* Projects */
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

@media (max-width: 700px) {
  .project-grid {
    grid-template-columns: 1fr;
  }
}

.project-card {
  border: 1px solid var(--color-border);
  border-radius: 2px;
  overflow: hidden;
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
}

.project-image {
  aspect-ratio: 16 / 9;
  background-image: var(--img);
  background-size: cover;
  background-position: center;
}

.project-body {
  padding: 1.35rem 1.5rem 1.5rem;
}

.project-body h3 {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  margin: 0 0 0.5rem;
}

.project-body p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--color-muted);
}

/* News */
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

@media (max-width: 900px) {
  .news-grid {
    grid-template-columns: 1fr;
  }
}

.news-card {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: 2px;
  background: var(--color-surface);
}

.news-card time {
  font-size: 0.8125rem;
  color: var(--color-muted);
}

.news-card h3 {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  margin: 0.35rem 0 0.5rem;
  line-height: 1.35;
}

.news-card p {
  margin: 0 0 1rem;
  font-size: 0.9375rem;
  color: var(--color-muted);
}

.text-link {
  font-weight: 600;
  font-size: 0.875rem;
  text-decoration: none;
}

.text-link:hover {
  text-decoration: underline;
}

/* Newsletter */
.newsletter-section {
  background: var(--color-accent);
  color: #fff;
}

.newsletter-section .section-title {
  color: #fff;
}

.newsletter-layout {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 1.5rem;
}

.newsletter-copy p {
  margin: 0;
  opacity: 0.92;
  max-width: 28rem;
}

.newsletter-form {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  flex: 1;
  min-width: min(100%, 22rem);
  max-width: 28rem;
}

.newsletter-form input {
  flex: 1;
  min-width: 12rem;
  padding: 0.75rem 1rem;
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  font-family: inherit;
  font-size: 1rem;
}

.newsletter-form input::placeholder {
  color: rgba(255, 255, 255, 0.65);
}

.newsletter-form input:focus {
  outline: none;
  border-color: #fff;
  background: rgba(255, 255, 255, 0.18);
}

.newsletter-form .btn-primary {
  flex-shrink: 0;
}

/* Footer */
.site-footer {
  background: #141816;
  color: #c5ccc8;
  padding-top: 3rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 2rem;
  padding-bottom: 2.5rem;
}

@media (max-width: 800px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 500px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.logo-footer {
  color: #fff;
}

.logo-footer:hover {
  color: #fff;
  opacity: 0.85;
}

.footer-brand p {
  margin: 0.75rem 0 0;
  font-size: 0.9375rem;
  max-width: 16rem;
}

.footer-heading {
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #fff;
  margin: 0 0 1rem;
}

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

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

.footer-links a {
  color: #c5ccc8;
  text-decoration: none;
  font-size: 0.9375rem;
}

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

.footer-contact,
.footer-address {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.5;
}

.footer-address {
  margin-top: 0.75rem;
  opacity: 0.75;
  font-size: 0.875rem;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 1.25rem 0;
}

.footer-bottom-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.8125rem;
  opacity: 0.85;
}

.footer-bottom p {
  margin: 0;
}

.footer-note a {
  color: #a8bfb5;
}

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

/* Inner pages */
.page-hero {
  padding: 3rem 0 2.5rem;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.page-hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 3.5vw, 2.35rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
  max-width: 40rem;
}

.page-lead {
  margin: 0;
  font-size: 1.0625rem;
  color: var(--color-muted);
  max-width: 44rem;
  line-height: 1.65;
}

.eyebrow-dark {
  color: var(--color-accent);
  opacity: 1;
}

.narrow-content {
  max-width: 48rem;
  margin-inline: auto;
  width: min(100% - 2rem, 48rem);
}

.prose {
  margin: 0 0 1rem;
  color: var(--color-text);
}

.prose.muted {
  color: var(--color-muted);
  font-size: 0.9375rem;
}

.prose-list {
  margin: 0 0 1.5rem;
  padding-left: 1.25rem;
  color: var(--color-muted);
}

.prose-list li {
  margin-bottom: 0.65rem;
}

.prose-list li strong {
  color: var(--color-text);
}

.disclaimer-box {
  padding: 1rem 1.25rem;
  margin-bottom: 2rem;
  background: var(--color-accent-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 0.9375rem;
  color: var(--color-text);
}

.disclaimer-inline {
  margin: 1.25rem 0 0;
  padding: 0.875rem 1rem;
  background: var(--color-bg);
  border-left: 3px solid var(--color-accent);
  font-size: 0.9375rem;
  color: var(--color-muted);
}

.demand-table-wrap {
  overflow-x: auto;
  margin: 1rem 0 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.demand-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}

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

.demand-table th {
  background: var(--color-bg);
  font-weight: 600;
  color: var(--color-text);
}

.demand-table tr:last-child td {
  border-bottom: 0;
}

.demand-table td:first-child {
  white-space: nowrap;
}

@media (max-width: 560px) {
  .demand-table td:first-child {
    white-space: normal;
  }
}

/* Tabs (biomass page) */
.tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.75rem;
  padding: 0;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 0.75rem;
}

.tab-btn {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.tab-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.tab-btn[aria-selected="true"] {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.tab-panel-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  margin: 0 0 0.75rem;
}

.tab-panel[hidden] {
  display: none;
}

.nav-list a.nav-current {
  color: var(--color-accent);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.nav-list a.nav-cta.nav-current {
  color: #fff;
  text-decoration: none;
}

.btn-inline {
  display: inline-flex;
  margin-top: 0.5rem;
}

.narrow-content > h2.section-title {
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
}

.narrow-content > h2.section-title:first-of-type {
  margin-top: 0;
}


.logo-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-mark {
  width: 3rem;
  height: auto;
}

.logo-text {
  font-family: var(--font-serif);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.25rem;
  width: 3.1rem;
  height: 2rem;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  border-radius: 999px;
  padding: 0 0.45rem;
  cursor: pointer;
}

.theme-icon {
  font-size: 0.8rem;
  line-height: 1;
}

html[data-theme="dark"] .site-footer {
  background: #040a06;
}