:root {
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 40px;
  --space-8: 56px;
  --radius-1: 12px;
  --radius-2: 16px;
  --radius-pill: 999px;
  --motion-fast: 180ms;
  --motion-med: 220ms;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --bg: #f7f5ef;
  --bg-spot: #edf1e6;
  --surface: #fffdf8;
  --surface-soft: #f1f4ec;
  --surface-strong: #ffffff;
  --text: #1d2b24;
  --muted: #58685e;
  --line: #d6dccb;
  --green: #0f5a3d;
  --green-soft: #def2e7;
  --orange-soft: #f9e9dc;
  --blue-soft: #dce9f6;
  --blue: #33678e;
  --shadow-lg: 0 14px 34px rgba(22, 38, 30, 0.11);
  --shadow-sm: 0 6px 18px rgba(22, 38, 30, 0.08);
  --header-bg: rgba(247, 245, 239, 0.9);
  --ambient-one: #c9e7d6;
  --ambient-two: #f1d2bb;
  --network-a: #f4eee3;
  --network-b: #eef4ed;
  --svg-node: #1c4735;
  --svg-line: #70877b;
  --footer: #738077;
  --focus-ring: rgba(15, 90, 61, 0.28);
  color-scheme: light;
}

html[data-theme="dark"] {
  --bg: #0f1512;
  --bg-spot: #17241d;
  --surface: #151f1a;
  --surface-soft: #1d2a24;
  --surface-strong: #1b2721;
  --text: #eaf3ed;
  --muted: #b4c4ba;
  --line: #2d3a33;
  --green: #82ddb9;
  --green-soft: #1a3b2f;
  --orange-soft: #35261a;
  --blue-soft: #1d2b37;
  --blue: #8bb5d6;
  --shadow-lg: 0 18px 30px rgba(0, 0, 0, 0.3);
  --shadow-sm: 0 8px 18px rgba(0, 0, 0, 0.22);
  --header-bg: rgba(15, 21, 18, 0.86);
  --ambient-one: #1a4d37;
  --ambient-two: #62402a;
  --network-a: #2b2820;
  --network-b: #1d3328;
  --svg-node: #9ce0c2;
  --svg-line: #5e7d6f;
  --footer: #90a097;
  --focus-ring: rgba(130, 221, 185, 0.32);
  color-scheme: dark;
}

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

html,
body {
  margin: 0;
  padding: 0;
}

body {
  color: var(--text);
  font-family: "Sora", "Segoe UI", sans-serif;
  line-height: 1.62;
  min-height: 100vh;
  background: radial-gradient(circle at 10% 8%, var(--bg-spot) 0%, var(--bg) 48%), var(--bg);
}

.ambient {
  pointer-events: none;
  position: fixed;
  border-radius: 50%;
  filter: blur(12px);
  opacity: 0.33;
  z-index: -1;
}

.ambient-one {
  width: 340px;
  height: 340px;
  right: -130px;
  top: -80px;
  background: var(--ambient-one);
}

.ambient-two {
  width: 290px;
  height: 290px;
  left: -130px;
  bottom: -80px;
  background: var(--ambient-two);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--line);
  background: var(--header-bg);
  backdrop-filter: blur(10px);
  transition:
    padding var(--motion-med) var(--ease-out),
    box-shadow var(--motion-med) var(--ease-out),
    background-color var(--motion-med) var(--ease-out);
}

.site-header.is-scrolled {
  padding: var(--space-2) var(--space-4);
  box-shadow: var(--shadow-sm);
}

.brand {
  text-decoration: none;
  color: var(--green);
  font-weight: 650;
  letter-spacing: 0.02em;
  font-size: 0.94rem;
}

.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.site-header nav {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.site-header nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 0.88rem;
  position: relative;
  padding-bottom: 2px;
  transition: color var(--motion-fast) var(--ease-out);
}

.site-header nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: var(--green);
  border-radius: var(--radius-pill);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--motion-med) var(--ease-out);
}

.site-header nav a:hover,
.site-header nav a.is-active {
  color: var(--green);
}

.site-header nav a:hover::after,
.site-header nav a.is-active::after {
  transform: scaleX(1);
}

.site-header nav a:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 3px;
  border-radius: 6px;
}

.theme-toggle {
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  padding: var(--space-2) var(--space-4);
  font-family: inherit;
  font-size: 0.81rem;
  font-weight: 600;
  color: var(--muted);
  background: var(--surface-strong);
  cursor: pointer;
  transition:
    color var(--motion-fast) var(--ease-out),
    border-color var(--motion-fast) var(--ease-out),
    transform var(--motion-fast) var(--ease-out),
    opacity var(--motion-fast) var(--ease-out);
}

.theme-toggle:hover {
  border-color: var(--green);
  color: var(--green);
}

.theme-toggle:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--focus-ring);
}

.theme-toggle:active {
  transform: translateY(1px);
}

.theme-toggle:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.section {
  width: min(1100px, calc(100% - 2rem));
  margin: 0 auto;
  padding: var(--space-8) 0 var(--space-5);
}

.hero {
  padding-top: calc(var(--space-8) + var(--space-2));
}

.kicker {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--green);
  font-size: 0.73rem;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: "IBM Plex Serif", Georgia, serif;
  line-height: 1.2;
}

h1 {
  margin-top: 0.6rem;
  max-width: 18ch;
  font-size: clamp(2rem, 5vw, 3.45rem);
}

.lede {
  margin: 1rem 0 0;
  color: var(--muted);
  max-width: 72ch;
}

.hero-cta-row {
  margin-top: var(--space-5);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-pill);
  text-decoration: none;
  border: 1px solid transparent;
  font-family: inherit;
  font-weight: 650;
  font-size: 0.88rem;
  line-height: 1;
  padding: var(--space-3) var(--space-5);
  cursor: pointer;
  transition:
    background-color var(--motion-med) var(--ease-out),
    border-color var(--motion-fast) var(--ease-out),
    transform var(--motion-fast) var(--ease-out),
    box-shadow var(--motion-fast) var(--ease-out),
    color var(--motion-fast) var(--ease-out),
    opacity var(--motion-fast) var(--ease-out);
}

.btn-primary {
  color: #ffffff;
  background: var(--green);
  border-color: color-mix(in srgb, var(--green) 70%, #000000 30%);
  box-shadow: 0 8px 20px rgba(15, 90, 61, 0.22);
}

.btn-primary:hover {
  background: color-mix(in srgb, var(--green) 88%, #ffffff 12%);
}

.btn-secondary {
  color: var(--text);
  background: var(--surface-soft);
  border-color: var(--line);
}

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

.btn:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--focus-ring);
}

.btn:active {
  transform: translateY(1px);
}

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.55;
  cursor: not-allowed;
  box-shadow: none;
}

.btn.is-loading {
  opacity: 0.75;
  pointer-events: none;
}

.meta-row {
  margin-top: var(--space-4);
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.meta-row span,
.trust-inline span,
.proof-badges span {
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--surface);
  color: var(--muted);
  font-size: 0.79rem;
  padding: var(--space-2) var(--space-4);
}

.trust-inline {
  margin-top: var(--space-4);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.trust-inline span {
  font-weight: 650;
  font-size: 0.76rem;
  padding: 6px var(--space-3);
}

.trust-section {
  padding-top: var(--space-5);
}

.section-heading {
  margin-bottom: var(--space-4);
}

.section-heading h2 {
  font-size: clamp(1.3rem, 2.8vw, 2.08rem);
}

.section-heading p {
  margin: 0.4rem 0 0;
  color: var(--muted);
  max-width: 70ch;
}

.split-two,
.benefit-grid {
  display: grid;
  gap: var(--space-4);
}

.split-two {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.benefit-grid {
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  margin-top: var(--space-4);
}

.trust-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: var(--space-3);
}

.card,
.trust-card,
.fact-card {
  border-radius: var(--radius-2);
  background: var(--surface-strong);
  box-shadow: var(--shadow-lg);
  border: none;
}

.benefit,
.panel,
.source-focus,
.collapsible {
  border: 1px solid var(--line);
  border-radius: var(--radius-2);
  background: var(--surface);
  box-shadow: none;
}

.card,
.panel,
.trust-card,
.benefit,
.fact-card {
  padding: var(--space-4);
}

.card h3,
.benefit h3,
.panel h3 {
  font-size: 1.14rem;
}

.card p,
.benefit p,
.panel p,
.panel li,
.card li {
  color: var(--muted);
}

.card ul,
.panel ul {
  margin: var(--space-2) 0 0;
  padding-left: 1rem;
}

.card li,
.panel li {
  margin-bottom: 0.45rem;
}

.benefit p {
  margin: 0.48rem 0 0;
  font-size: 0.94rem;
}

.graphic-card {
  overflow: hidden;
}

.what-not,
.panel.caution {
  background: linear-gradient(160deg, var(--surface-strong), var(--orange-soft));
}

.trust-number {
  margin: 0;
  color: var(--green);
  font-family: "IBM Plex Serif", Georgia, serif;
  font-size: 1.72rem;
  font-weight: 700;
}

.trust-label {
  margin: 0.28rem 0 0;
  color: var(--muted);
  font-size: 0.84rem;
}

.proof-badges {
  margin-top: var(--space-4);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.network-svg {
  width: 100%;
  height: auto;
  margin-top: 0.8rem;
}

.network-svg rect {
  fill: var(--network-a);
  stroke: var(--line);
}

.network-svg rect:nth-of-type(2) {
  fill: var(--network-b);
}

.network-svg text {
  font-family: "Sora", sans-serif;
  font-size: 15px;
  font-weight: 700;
  fill: var(--text);
}

.network-svg circle {
  fill: var(--svg-node);
}

.network-svg line {
  stroke: var(--svg-line);
  stroke-width: 2;
}

.compare-card {
  overflow-x: auto;
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: var(--space-3);
  font-size: 0.88rem;
}

.compare-table thead th {
  text-align: left;
  background: var(--green-soft);
  color: var(--text);
  font-weight: 700;
  padding: var(--space-3);
  border-bottom: 1px solid var(--line);
}

.compare-table tbody th,
.compare-table tbody td {
  text-align: left;
  vertical-align: top;
  padding: var(--space-3);
  border-bottom: 1px solid var(--line);
  color: var(--muted);
}

.compare-table tbody th {
  color: var(--text);
  width: 24%;
}

.compare-table tbody tr:last-child th,
.compare-table tbody tr:last-child td {
  border-bottom: none;
}

.misconception-list {
  margin: var(--space-3) 0 0;
  padding-left: 1.15rem;
}

.misconception-list li {
  margin-bottom: 0.62rem;
  color: var(--muted);
}

.subsection-title {
  margin: var(--space-5) 0 var(--space-3);
  color: var(--text);
  font-size: 1.3rem;
}

.section-divider {
  border: 0;
  height: 1px;
  margin: var(--space-6) 0 var(--space-4);
  background: linear-gradient(
    90deg,
    transparent 0%,
    color-mix(in srgb, var(--line) 35%, var(--green) 65%) 25%,
    color-mix(in srgb, var(--line) 35%, var(--green) 65%) 75%,
    transparent 100%
  );
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--space-3);
}

.fact-card {
  position: relative;
  padding-top: calc(var(--space-4) + 4px);
  background: var(--surface-strong);
}

.fact-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  border-radius: 16px 16px 0 0;
  background: linear-gradient(90deg, var(--green), var(--blue));
}

.fact-card.tier-a {
  grid-column: span 6;
}

.fact-card.tier-b {
  grid-column: span 4;
}

.fact-card.tier-c {
  grid-column: span 4;
}

.fact-card.tier-a .fact-number {
  font-size: 2.05rem;
}

.fact-card.tier-b .fact-number {
  font-size: 1.6rem;
}

.fact-card.tier-c .fact-number {
  font-size: 1.34rem;
}

.muted-stat {
  background: var(--surface-soft);
}

.fact-number {
  margin: 0;
  color: var(--green);
  font-weight: 700;
}

.fact-text {
  margin: 0.4rem 0 0;
  color: var(--muted);
  font-size: 0.93rem;
}

.mix-row-label {
  margin: 0.75rem 0 0.4rem;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--text);
}

.mix-bar {
  margin-top: var(--space-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-1);
  overflow: hidden;
  display: flex;
  min-height: 46px;
}

.mix {
  width: calc(var(--w) * 1%);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.74rem;
  font-weight: 600;
  white-space: nowrap;
  color: #ffffff;
  padding: 0.35rem;
  overflow: hidden;
}

.mix.sustainable {
  background: #2f8b65;
}

.mix.gas {
  background: #8d6b57;
}

.mix.coal {
  background: #545454;
}

.mix.other-fossil {
  background: #7a5f51;
}

.mix-other-note {
  margin: 0.35rem 0 0;
  font-size: 0.78rem;
  color: var(--muted);
}

.micro-note {
  margin: 0.7rem 0 0;
  color: var(--muted);
  font-size: 0.86rem;
}

.emphasis-note {
  margin-top: 0;
  background: var(--surface-soft);
  border-radius: var(--radius-1);
  padding: var(--space-3);
}

.flow-list {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.flow-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  border: 1px solid var(--line);
  background: var(--blue-soft);
  border-radius: var(--radius-1);
  padding: var(--space-3);
  color: var(--text);
  font-weight: 600;
}

.flow-list span {
  color: var(--text);
}

.flow-arrow-svg {
  width: 20px;
  height: 20px;
  flex: 0 0 auto;
}

.flow-arrow-svg path {
  fill: none;
  stroke: var(--blue);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
}

.collapsible {
  margin-top: var(--space-4);
  overflow: hidden;
}

.collapsible summary {
  list-style: none;
  cursor: pointer;
  padding: var(--space-3) var(--space-4);
  font-weight: 650;
  color: var(--text);
}

.collapsible summary::-webkit-details-marker {
  display: none;
}

.collapsible[open] summary {
  border-bottom: 1px solid var(--line);
}

.collapsible ul,
.collapsible ol {
  margin: 0;
  padding: var(--space-3) var(--space-4) var(--space-4) calc(var(--space-4) + 1rem);
}

.collapsible li {
  color: var(--muted);
  margin-bottom: var(--space-2);
}

.cta-footer {
  padding-top: var(--space-6);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.source-focus {
  margin-top: var(--space-4);
  padding: var(--space-4);
  background: var(--surface-soft);
}

.source-focus h3 {
  font-size: 1.06rem;
}

.source-focus ul {
  margin: var(--space-2) 0 0;
  padding-left: 1.1rem;
}

.source-focus li {
  color: var(--muted);
  margin-bottom: 0.42rem;
}

.sources h2 {
  font-size: clamp(1.3rem, 2.8vw, 2.08rem);
}

.sources ol {
  margin: var(--space-3) 0 0;
  padding-left: 1.2rem;
}

.sources li {
  margin: 0 0 0.5rem;
  color: var(--muted);
}

.sources span {
  color: var(--green);
  font-weight: 700;
}

.sources a {
  color: var(--green);
  word-break: break-word;
}

.site-footer {
  width: min(1100px, calc(100% - 2rem));
  margin: 0 auto;
  padding: var(--space-7) 0 var(--space-8);
  color: var(--footer);
  font-size: 0.88rem;
}

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition:
    opacity 520ms var(--ease-out),
    transform 520ms var(--ease-out);
}

[data-reveal].visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 980px) {
  .fact-card.tier-a,
  .fact-card.tier-b,
  .fact-card.tier-c {
    grid-column: span 6;
  }
}

@media (max-width: 860px) {
  .site-header nav {
    gap: var(--space-2);
  }

  .flow-list li {
    align-items: flex-start;
  }

  .compare-table {
    min-width: 640px;
  }
}

@media (max-width: 740px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .header-actions {
    width: 100%;
    justify-content: space-between;
  }

  .section {
    padding-top: var(--space-6);
  }

  .hero {
    padding-top: var(--space-7);
  }

  .fact-card.tier-a,
  .fact-card.tier-b,
  .fact-card.tier-c {
    grid-column: span 12;
  }
}

@media (max-width: 560px) {
  .cta-row {
    flex-direction: column;
  }

  .cta-row .btn {
    width: 100%;
  }

  .mix {
    font-size: 0.67rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .site-header,
  .btn,
  .site-header nav a::after {
    transition: none;
  }
}

@media print {
  .site-header,
  .ambient,
  .theme-toggle,
  .cta-footer {
    display: none !important;
  }

  body {
    background: #ffffff;
    color: #101010;
  }

  .section,
  .site-footer {
    width: 100%;
    max-width: none;
  }

  .card,
  .benefit,
  .panel,
  .fact-card,
  .source-focus,
  .collapsible {
    box-shadow: none;
    border: 1px solid #d9d9d9;
    break-inside: avoid;
  }
}