@charset "UTF-8";

:root {
  color-scheme: light;
  --paper: #f6f4eb;
  --ink: #182637;
  --muted: #65716f;
  --blue: #2359ef;
  --blue-dark: #1641c3;
  --blue-soft: #e8edfc;
  --orange: #ee7141;
  --line: #d8ddd3;
  --card: #fffef8;
  --radius: 26px;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 36px; }
body { margin: 0; background: var(--paper); color: var(--ink); }
button, input { font: inherit; }
button, a, input { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
a { color: inherit; text-underline-offset: 4px; }
button:focus-visible, a:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 3px solid var(--orange); outline-offset: 5px;
}
::selection { color: white; background: var(--blue); }

.site-header, main, .site-footer { width: min(1360px, calc(100% - 104px)); margin-inline: auto; }
.site-header { min-height: 102px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 11px; text-decoration: none; font-size: 15px; font-weight: 800; letter-spacing: -.65px; }
.brand-mark { width: 27px; height: 33px; display: inline-flex; align-items: center; justify-content: center; color: var(--blue); font-size: 27px; line-height: 1; }
.brand-mark svg { display: block; width: 100%; height: 100%; }
.site-header nav { display: flex; align-items: center; gap: 30px; }
.site-header nav a { text-decoration: none; font-size: 13px; font-weight: 600; }
.site-header nav a:hover { color: var(--blue); }
.top-note { padding: 17px 0 0; color: var(--muted); font-size: 11px; line-height: 1.6; letter-spacing: .025em; }

.hero { display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 40px; padding: 70px 0 76px; }
.eyebrow { margin: 0 0 22px; font-size: 10px; font-weight: 800; letter-spacing: .17em; text-transform: uppercase; line-height: 1.7; }
.hero .eyebrow { display: flex; align-items: center; gap: 9px; }
.hero .eyebrow::before { content: ""; width: 7px; height: 7px; background: var(--orange); border-radius: 50%; flex-shrink: 0; }
h1 { max-width: 730px; margin: 0; font-size: clamp(48px, 5.7vw, 88px); line-height: .99; font-weight: 750; letter-spacing: -.072em; }
h1 span { color: var(--blue); }
.intro { max-width: 405px; margin: 25px 0 32px; color: var(--muted); font-size: 15px; line-height: 1.75; }
.metric { display: flex; flex-wrap: wrap; align-items: baseline; gap: 10px; }
.metric strong { color: var(--blue); font-size: clamp(46px, 5.3vw, 77px); line-height: 1.08; letter-spacing: -.065em; font-weight: 750; font-variant-numeric: tabular-nums; }
.metric-unit { max-width: 130px; font-size: 14px; font-weight: 550; line-height: 1.3; }
.status { max-width: 390px; min-height: 36px; margin: 13px 0 21px; font-size: 12px; color: var(--muted); line-height: 1.6; }
.primary-button, .secondary-button { min-height: 48px; display: inline-flex; justify-content: center; align-items: center; gap: 10px; border: 1px solid transparent; border-radius: 100px; padding: 14px 23px; font-weight: 650; font-size: 12px; line-height: 1.3; transition: background .18s ease, transform .18s ease, box-shadow .18s ease; }
.primary-button { background: var(--ink); color: white; }
.primary-button:hover { background: var(--blue); transform: translateY(-2px); }
.secondary-button { border-color: #c8cfc6; background: transparent; color: var(--ink); }
.secondary-button:hover { background: white; border-color: var(--ink); transform: translateY(-2px); }
.primary-button:active, .secondary-button:active { transform: translateY(0); }
button:disabled { opacity: .5; cursor: wait; }

.scene-card { position: relative; align-self: stretch; display: flex; flex-direction: column; align-items: center; justify-content: center; min-width: 0; min-height: 450px; padding: 20px 0; }
.scene-card::before { position: absolute; content: ""; inset: 8% 0 11%; border-radius: 50%; background: radial-gradient(ellipse, #e5e9e240 0%, transparent 70%); z-index: -1; }
#reservoir { width: 112%; max-width: none; overflow: visible; height: auto; display: block; }
.scene-caption { max-width: 370px; margin: -7px auto 0; color: var(--muted); font-size: 10px; line-height: 1.7; text-align: center; letter-spacing: .02em; }
.scene-caption strong { color: var(--ink); font-weight: 600; }
.tank-outline { fill: none; stroke: #8c9a9d; stroke-width: 1.3; stroke-linejoin: round; }
.tank-floor { fill: #e4e8dd; stroke: #bec7bd; stroke-width: 1; }
.water-front { fill: #245ef2; fill-opacity: .93; }
.water-side { fill: #1646c9; fill-opacity: .94; }
.water-top { fill: #7198ff; fill-opacity: .96; }
.water-ripple { fill: none; stroke: #b3d3ff; stroke-width: 1.5; stroke-linecap: round; opacity: .7; }
#reservoir text { font-family: inherit; }

.explore { border-top: 1px solid var(--line); padding: 50px 0 64px; display: grid; grid-template-columns: .8fr 1.2fr; column-gap: 66px; align-items: start; }
.section-heading .eyebrow { margin-bottom: 15px; color: var(--muted); }
h2 { font-size: clamp(31px, 3.2vw, 46px); letter-spacing: -.055em; line-height: 1.08; margin: 0; font-weight: 700; max-width: 440px; }
.section-heading > p:not(.eyebrow) { color: var(--muted); font-size: 14px; line-height: 1.75; max-width: 350px; }
.controls-panel { min-width: 0; background: var(--card); border: 1px solid #dde1d7; border-radius: var(--radius); padding: 30px; box-shadow: 0 7px 24px #18263703; }
.timeline-label { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; font-size: 12px; font-weight: 650; }
#yearValue { font-size: 29px; line-height: 1; color: var(--blue); font-weight: 750; letter-spacing: -.045em; font-variant-numeric: tabular-nums; }
input[type="range"] { --range-progress: 50%; display: block; appearance: none; -webkit-appearance: none; width: 100%; margin: 25px 0 12px; height: 6px; background: #dce3ee; border-radius: 5px; accent-color: var(--blue); cursor: pointer; }
input[type="range"]::-webkit-slider-thumb { appearance: none; -webkit-appearance: none; width: 21px; height: 21px; background: var(--blue); border: 4px solid white; box-shadow: 0 0 0 1px var(--blue), 0 2px 5px #18263718; border-radius: 50%; }
input[type="range"]::-moz-range-thumb { width: 14px; height: 14px; background: var(--blue); border: 4px solid white; box-shadow: 0 0 0 1px var(--blue); border-radius: 50%; }
input[type="range"]::-moz-range-progress { background: var(--blue); height: 6px; border-radius: 5px; }
.timeline-ends { display: flex; justify-content: space-between; gap: 8px; color: var(--muted); font-size: 10px; }
#timelineNote { min-height: 30px; font-size: 11px; line-height: 1.6; margin: 18px 0 24px; color: var(--muted); }
.comparison-tabs { display: flex; flex-wrap: wrap; gap: 6px; border-top: 1px solid var(--line); padding-top: 23px; }
.comparison-tabs button { flex: 1 0 auto; background: transparent; color: #606c69; border: 1px solid #d8ddd3; border-radius: 100px; padding: 10px 13px; font-size: 11px; font-weight: 650; transition: background .18s ease, border-color .18s ease; }
.comparison-tabs button:hover { border-color: var(--blue); color: var(--blue); }
.comparison-tabs button[aria-pressed="true"] { background: var(--blue); color: white; border-color: var(--blue); }
.equivalent { padding: 28px 0 0; }
.equivalent strong { display: block; color: var(--ink); font-size: clamp(35px, 4.2vw, 57px); line-height: 1.05; font-weight: 700; letter-spacing: -.055em; font-variant-numeric: tabular-nums; overflow-wrap: anywhere; }
.equivalent p { margin: 10px 0 0; font-size: 14px; line-height: 1.5; }
.comparison-note { margin: 10px 0 24px; color: var(--muted); font-size: 10px; line-height: 1.6; }
.share-actions { display: flex; flex-wrap: wrap; gap: 9px; }
.share-actions button { flex: 1 1 auto; min-height: 43px; font-size: 11px; padding: 12px 18px; }
#shareFeedback { color: var(--muted); font-size: 11px; line-height: 1.6; margin: 10px 0 0; min-height: 0; }
#shareFeedback:empty { display: none; }

.context { border-top: 1px solid var(--line); padding: 52px 0 62px; }
.context .section-heading { margin-bottom: 32px; }
.context-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.context-grid article { padding: 26px 26px 29px; border: 1px solid var(--line); border-radius: 20px; }
.number { display: block; color: var(--orange); font-size: 11px; font-weight: 750; letter-spacing: .06em; margin-bottom: 28px; }
h3 { font-size: 19px; letter-spacing: -.045em; line-height: 1.2; margin: 0 0 12px; font-weight: 700; }
.context-grid p { color: var(--muted); font-size: 12px; line-height: 1.75; margin: 0; }
.methodology { padding: 0 0 62px; }
.methodology details { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.methodology summary { padding: 23px 0; font-size: 13px; font-weight: 650; cursor: pointer; list-style: none; display: flex; justify-content: space-between; gap: 20px; }
.methodology summary::-webkit-details-marker { display: none; }
.methodology summary::after { content: "+"; color: var(--blue); font-size: 20px; font-weight: 400; line-height: .8; }
.methodology details[open] summary::after { content: "−"; }
.methodology-content { max-width: 860px; padding: 0 0 23px; color: var(--muted); font-size: 12px; line-height: 1.9; }
.methodology-content p { margin: 0 0 13px; }
.methodology-content ol { padding-left: 19px; }
.methodology-content li { padding-left: 5px; margin-bottom: 9px; }
.methodology-content a { color: var(--blue); overflow-wrap: anywhere; }
.site-footer { border-top: 1px solid var(--line); padding: 25px 0 34px; display: flex; justify-content: space-between; gap: 25px; color: var(--muted); font-size: 10px; line-height: 1.7; }
.site-footer p { margin: 0; }
.site-footer a { text-decoration: none; }
.site-footer a:hover { color: var(--blue); }

@media (min-width: 1550px) {
  .hero { padding-block: 86px; }
  h1 { font-size: 92px; }
}
@media (max-width: 1100px) {
  .site-header, main, .site-footer { width: calc(100% - 64px); }
  .hero { gap: 15px; padding-block: 60px; }
  h1 { font-size: clamp(48px, 6.2vw, 70px); }
  .scene-card { min-height: 380px; }
  #reservoir { width: 112%; }
  .explore { column-gap: 36px; grid-template-columns: .8fr 1.2fr; }
  .controls-panel { padding: 26px; }
  .context-grid article { padding: 22px; }
}
@media (max-width: 760px) {
  .site-header, main, .site-footer { width: calc(100% - 40px); }
  .site-header { min-height: 80px; gap: 12px; }
  .brand { font-size: 13px; letter-spacing: -.5px; gap: 7px; }
  .brand-mark { width: 22px; height: 27px; font-size: 23px; }
  .site-header nav { gap: 18px; }
  .site-header nav a { font-size: 11px; }
  .hero { grid-template-columns: 1fr; gap: 5px; padding: 43px 0 35px; }
  .eyebrow { font-size: 9px; margin-bottom: 20px; }
  h1 { font-size: clamp(49px, 11vw, 76px); max-width: 610px; }
  .intro { max-width: 450px; margin-block: 23px; font-size: 14px; }
  .metric strong { font-size: clamp(51px, 10vw, 71px); }
  .metric-unit { max-width: 160px; font-size: 13px; }
  .status { min-height: 0; max-width: 450px; }
  .scene-card { min-height: 0; padding: 4px 0 15px; max-width: 580px; width: 100%; margin: 0 auto; }
  #reservoir { width: 100%; max-height: 390px; }
  .scene-caption { margin: -14px auto 0; font-size: 9px; max-width: 310px; }
  .explore { grid-template-columns: 1fr; padding: 35px 0 42px; gap: 25px; }
  h2 { font-size: 36px; max-width: 450px; }
  .controls-panel { padding: 25px; border-radius: 23px; }
  .equivalent strong { font-size: 47px; }
  .context { padding: 36px 0 40px; }
  .context-grid { grid-template-columns: 1fr; gap: 12px; }
  .context-grid article { padding: 24px; }
  .number { margin-bottom: 19px; }
  .context-grid p { max-width: 560px; }
  .methodology { padding-bottom: 40px; }
  .site-footer { flex-direction: column; gap: 12px; padding-bottom: 25px; }
}
@media (max-width: 390px) {
  .site-header, main, .site-footer { width: calc(100% - 30px); }
  .site-header nav { gap: 11px; }
  .brand { font-size: 12px; }
  .brand-mark { width: 18px; }
  h1 { font-size: 45px; }
  .controls-panel { padding: 21px; }
  .comparison-tabs button { padding-inline: 10px; font-size: 10px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}