/* Gas Standing Charge Impact Calculator
   Palette mirrors ../topten (Styles/_palette.scss). Hex codes appear ONLY in this :root
   block — every other rule consumes a token. */

:root {
  /* Brand */
  --color-brand-blue: #006580;
  --color-brand-red: #cf3339;
  --color-brand-purple: #5b315e;
  --color-brand-orange: #ee7623;
  --color-brand-pastel-purple: #d5c2d7;
  --color-brand-pastel-green: #9ed8b3;

  /* Semantic */
  --color-primary: #006580;
  --color-primary-light: #d1e3e8;
  --color-primary-hover: #007795;
  --color-primary-dark: #063a47;

  --color-success: #9ed8b3;
  --color-success-light: #e8f6ee;
  --color-success-dark: #296740;

  --color-danger: #cf3339;
  --color-danger-light: #f9e6e7;
  --color-danger-dark: #8f1f24;

  --color-warning: #d19a56;
  --color-warning-light: #faf3e9;
  --color-warning-dark: #8a6534;

  /* Chrome */
  --color-nav-bg: #006580;
  --color-nav-bg-hover: #0095bd;
  --color-nav-accent: #66a3b3;
  --color-nav-text: #ffffff;

  --color-hero-bg: #d1e3e8;
  --color-hero-text: #063a47;
  --color-hero-rule: #73aab9;

  /* Neutrals */
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-bg-muted: #eef2f6;
  --color-border: #cbd5e1;
  --color-border-weak: #e2e8f0;
  --color-text: #1e293b;
  --color-text-muted: #64748b;

  --radius: 8px;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.5;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---------- Navbar ---------- */

.navbar {
  background-color: var(--color-nav-bg);
  border-bottom: 3px solid var(--color-nav-accent);
  color: var(--color-nav-text);
}

.navbar .container {
  display: flex;
  align-items: center;
  min-height: 3.5rem;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--color-nav-text);
  text-decoration: none;
  font-weight: 700;
  font-size: 1.05rem;
}

.navbar-brand:hover {
  color: var(--color-nav-text);
}

.navbar-logo {
  height: 2rem;
  width: auto;
}

.navbar-tagline {
  margin-left: auto;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.8);
}

@media (max-width: 640px) {
  .navbar-tagline {
    display: none;
  }
}

/* ---------- Hero ---------- */

/* The hero reflows: on wide screens the heading and narrative sit side by side and
   share the full width; when they no longer fit they wrap to a stacked, full-width
   layout. This avoids the narrative wrapping early against a hard character cap
   while it still has room on wider viewports. */
.hero {
  background-color: var(--color-hero-bg);
  color: var(--color-hero-text);
  border-radius: var(--radius);
  padding: 1.75rem 2rem;
  margin: 1.5rem 0;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 0.6rem 2.5rem;
}

.hero h1 {
  flex: 1 1 20rem;
  margin: 0;
  font-size: 1.6rem;
  line-height: 1.25;
  text-wrap: balance;
}

.hero-narrative {
  flex: 2 1 30rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.hero p {
  margin: 0;
  font-size: 0.98rem;
  text-wrap: pretty;
}

@media (max-width: 640px) {
  .hero {
    padding: 1.25rem 1.25rem;
  }
}

/* ---------- Layout ---------- */

main {
  flex: 1 0 auto;
}

.calc-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 1.5rem;
  align-items: start;
  margin-bottom: 1.5rem;
}

@media (max-width: 820px) {
  .calc-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

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

.card h2 {
  margin: 0 0 1rem;
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}

/* ---------- Inputs ---------- */

.field {
  margin-bottom: 1.35rem;
}

.field:last-child {
  margin-bottom: 0;
}

/* Collapsible panels (rate inputs, results detail, footer sources). Native
   <details>/<summary>; collapsed unless the page opts an instance open. */
.rate-panel,
.more-panel,
.sources-panel {
  border: 1px solid var(--color-border-weak);
  border-radius: 6px;
  background-color: var(--color-bg);
  margin-top: 0.25rem;
}

.rate-panel > summary,
.more-panel > summary,
.sources-panel > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.65rem 0.85rem;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  list-style: none;
}

.rate-panel > summary::-webkit-details-marker,
.more-panel > summary::-webkit-details-marker,
.sources-panel > summary::-webkit-details-marker {
  display: none;
}

.rate-panel > summary::after,
.more-panel > summary::after,
.sources-panel > summary::after {
  content: "+";
  font-weight: 700;
  color: var(--color-text-muted);
}

.rate-panel[open] > summary::after,
.more-panel[open] > summary::after,
.sources-panel[open] > summary::after {
  content: "\2212";
}

.rate-panel-body,
.more-panel-body,
.sources-panel-body {
  padding: 1rem 0.85rem 0.85rem;
  border-top: 1px solid var(--color-border-weak);
}

.field label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

.field .hint {
  display: block;
  font-weight: 400;
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-top: 0.2rem;
}

.input-row {
  display: flex;
  align-items: stretch;
  gap: 0.5rem;
}

.input-row .prefix,
.input-row .suffix {
  display: flex;
  align-items: center;
  padding: 0 0.7rem;
  background-color: var(--color-bg-muted);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  white-space: nowrap;
}

input[type="text"] {
  flex: 1 1 auto;
  width: 100%;
  min-width: 0;
  padding: 0.55rem 0.7rem;
  font: inherit;
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 6px;
}

input[type="text"]:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
  border-color: var(--color-primary);
}

input[type="range"] {
  width: 100%;
  margin: 0.6rem 0 0;
  accent-color: var(--color-primary);
}

.presets {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.6rem;
}

.preset {
  font: inherit;
  font-size: 0.82rem;
  padding: 0.3rem 0.65rem;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background-color: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
}

.preset:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.preset.is-active {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

/* ---------- Result ---------- */

.breakdown {
  border: 1px solid var(--color-border-weak);
  border-radius: 6px;
  background-color: var(--color-bg);
  margin-bottom: 1.25rem;
  overflow: hidden;
}

.breakdown-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.6rem 0.85rem;
  border-bottom: 1px solid var(--color-border-weak);
}

.breakdown-row:last-child {
  border-bottom: none;
}

.breakdown-label {
  font-size: 0.9rem;
}

.breakdown-value {
  font-weight: 700;
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

.breakdown-value.is-credit {
  color: var(--color-success-dark);
}

.breakdown-value.is-debit {
  color: var(--color-danger-dark);
}

.breakdown-value.is-muted {
  color: var(--color-text-muted);
}

.verdict {
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  margin-bottom: 1.25rem;
}

.verdict .verdict-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  opacity: 0.85;
}

.verdict .verdict-amount {
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1.1;
  margin: 0.15rem 0;
}

.verdict .verdict-sub {
  font-size: 0.9rem;
}

.verdict.is-gain {
  background-color: var(--color-success-light);
  border: 1px solid var(--color-success);
  color: var(--color-success-dark);
}

.verdict.is-loss {
  background-color: var(--color-danger-light);
  border: 1px solid var(--color-danger);
  color: var(--color-danger-dark);
}

.verdict.is-neutral {
  background-color: var(--color-bg-muted);
  border: 1px solid var(--color-border);
  color: var(--color-text);
}

.comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.comparison .stat {
  border: 1px solid var(--color-border-weak);
  border-radius: 6px;
  padding: 0.7rem 0.85rem;
  background-color: var(--color-bg);
}

.comparison .stat .stat-label {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.comparison .stat .stat-value {
  font-size: 1.25rem;
  font-weight: 700;
}

.comparison .stat .stat-note {
  font-size: 0.78rem;
  color: var(--color-text-muted);
}

/* Bars */

.bars {
  margin-bottom: 1.25rem;
}

/* Inside the results "More" panel the container already provides spacing. */
.more-panel-body .bars {
  margin-bottom: 0;
}

.bar-row {
  margin-bottom: 0.7rem;
}

.more-panel-body .bar-row:last-child {
  margin-bottom: 0;
}

.bar-row .bar-head {
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  margin-bottom: 0.25rem;
}

.bar-track {
  height: 0.7rem;
  background-color: var(--color-bg-muted);
  border-radius: 999px;
  overflow: hidden;
}

.bar-fill {
  height: 100%;
  border-radius: 999px;
  transition: width 0.2s ease;
}

.bar-fill.is-old {
  background-color: var(--color-primary);
}

.bar-fill.is-new {
  background-color: var(--color-brand-purple);
}

/* Break-even */

.breakeven {
  border-top: 1px solid var(--color-border-weak);
  padding-top: 1rem;
  font-size: 0.92rem;
}

.breakeven .be-value {
  font-weight: 700;
}

/* ---------- Caveats ---------- */

.caveats {
  background-color: var(--color-warning-light);
  border: 1px solid var(--color-warning);
  border-left-width: 4px;
  border-radius: var(--radius);
  margin-bottom: 2rem;
}

.caveats > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 1.1rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-warning-dark);
  cursor: pointer;
  list-style: none;
}

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

.caveats > summary::after {
  content: "+";
  font-weight: 700;
}

.caveats[open] > summary::after {
  content: "\2212";
}

.caveats[open] > summary {
  padding-bottom: 0.75rem;
}

.caveats ul {
  margin: 0;
  padding: 0 1.5rem 1.25rem 2.7rem;
}

.caveats li {
  margin-bottom: 0.45rem;
  font-size: 0.92rem;
}

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

/* ---------- Footer ---------- */

footer {
  border-top: 1px solid var(--color-border-weak);
  background-color: var(--color-surface);
  padding: 1.25rem 0;
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

footer p {
  margin: 0.2rem 0;
}

.sources {
  margin: 0;
  padding-left: 1.1rem;
  max-width: 82ch;
}

.sources li {
  margin-bottom: 0.4rem;
}

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

.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;
}