:root {
  color-scheme: light dark;
  --font-sans: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-serif: "Georgia", "Times New Roman", serif;
  --font-mono: "IBM Plex Mono", "SFMono-Regular", Menlo, monospace;
  --color-bg: #f6f4f2;
  --color-surface: #ffffff;
  --color-surface-alt: #f0ece8;
  --color-text: #171b24;
  --color-text-muted: #3f4757;
  --color-text-inverse: #f8f3ef;
  --color-border: #d5d0ca;
  --color-accent: #7c5dfa;
  --color-accent-soft: rgba(124, 93, 250, 0.14);
  --color-success: #2f9e44;
  --color-warning: #f08c00;
  --color-danger: #d9480f;
  --color-gradient-start: #263048;
  --color-gradient-end: #191f33;
  --color-hero-line: rgba(255, 255, 255, 0.7);
  --shadow-soft: 0 12px 32px rgba(15, 18, 24, 0.08);
  --shadow-hover: 0 16px 40px rgba(15, 18, 24, 0.12);
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --radius-xs: 8px;
  --gap-xs: 8px;
  --gap-sm: 12px;
  --gap-md: 20px;
  --gap-lg: 28px;
  --gap-xl: 40px;
  --line-height-base: 1.6;
  --transition-base: 220ms ease;
  --max-width: min(1180px, 92vw);
}

[data-theme="dark"] {
  --color-bg: #0f1218;
  --color-surface: #161b26;
  --color-surface-alt: #1f2633;
  --color-text: #f8f3ef;
  --color-text-muted: rgba(248, 243, 239, 0.72);
  --color-text-inverse: #161b26;
  --color-border: rgba(120, 130, 155, 0.35);
  --color-gradient-start: #19264a;
  --color-gradient-end: #0b101c;
  --color-hero-line: rgba(124, 93, 250, 0.65);
  --shadow-soft: 0 12px 32px rgba(0, 0, 0, 0.35);
  --shadow-hover: 0 18px 48px rgba(0, 0, 0, 0.45);
}

* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  line-height: var(--line-height-base);
  background: var(--color-bg);
  color: var(--color-text);
  transition: background var(--transition-base), color var(--transition-base);
}

body:focus-visible {
  outline: none;
}

img,
svg {
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
  text-decoration: none;
  position: relative;
}

a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 1.5px;
  background: currentColor;
  opacity: 0.25;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

a:hover::after,
a:focus-visible::after {
  opacity: 0.55;
  transform: scaleX(1);
}

.page {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.no-js {
  padding: 1.5rem;
  background: var(--color-danger);
  color: #fff;
  text-align: center;
  font-weight: 600;
}

.site-header {
  position: relative;
  overflow: hidden;
  color: var(--color-text-inverse);
}

.site-header__background {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.site-header__content {
  position: relative;
  padding: var(--gap-xl) 0 var(--gap-lg);
  backdrop-filter: blur(16px);
}

.top-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gap-md);
  max-width: var(--max-width);
  margin: 0 auto var(--gap-xl);
  padding: 0 var(--gap-md);
}

.top-nav .brand {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: var(--gap-sm);
  padding: 0;
  margin: 0;
}

.nav-links a {
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-xs);
  transition: background var(--transition-base);
}

.nav-links a:hover,
.nav-links a:focus-visible {
  background: rgba(248, 248, 248, 0.18);
}

.icon-button {
  border: none;
  background: transparent;
  color: inherit;
  font-size: 1.1rem;
  padding: 0.5rem;
  border-radius: 50%;
  cursor: pointer;
  transition: background var(--transition-base), transform var(--transition-base);
}

.icon-button:hover,
.icon-button:focus-visible {
  background: rgba(255, 255, 255, 0.16);
  transform: translateY(-1px);
}

.icon-button:focus-visible,
.button:focus-visible,
.chip:focus-visible,
.modal__close:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
}

.button {
  border: none;
  background: var(--color-accent);
  color: #fff;
  font-weight: 600;
  padding: 0.75rem 1.4rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: transform var(--transition-base), box-shadow var(--transition-base), background var(--transition-base);
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.button:active {
  transform: translateY(0);
}

.button--ghost {
  background: transparent;
  color: inherit;
  border: 1.5px solid currentColor;
}

.hero {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  align-items: center;
  gap: var(--gap-xl);
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap-md);
}

.hero__content h1 {
  font-size: clamp(2.6rem, 5vw, 3.6rem);
  margin-bottom: var(--gap-md);
}

.hero__content p {
  font-size: 1.05rem;
  max-width: 36ch;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-sm);
  margin-top: var(--gap-md);
}

.hero__visual {
  justify-self: center;
  padding: var(--gap-md);
  background: rgba(10, 12, 20, 0.35);
  border-radius: var(--radius-lg);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
}

.hero-silhouette {
  filter: drop-shadow(0 18px 28px rgba(0, 0, 0, 0.35));
}

main {
  flex: 1;
  background: var(--color-bg);
}

.section {
  padding: var(--gap-xl) 0;
}

.section--panel {
  background: var(--color-surface);
  box-shadow: var(--shadow-soft);
  border-radius: var(--radius-lg);
  margin: var(--gap-xl) auto;
  max-width: var(--max-width);
  padding: var(--gap-xl);
}

.section__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gap-md);
  flex-wrap: wrap;
  margin-bottom: var(--gap-lg);
}

.section__header h2 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  margin: 0;
}

.section__actions {
  display: flex;
  gap: var(--gap-sm);
  align-items: center;
}

.section__intro {
  max-width: var(--max-width);
  margin: 0 auto var(--gap-lg);
  padding: 0 var(--gap-md);
  color: var(--color-text-muted);
}

.filters {
  display: grid;
  gap: var(--gap-md);
  margin-bottom: var(--gap-lg);
}

.field {
  display: grid;
  gap: var(--gap-xs);
  color: inherit;
}

.field input[type="search"],
.field input[type="range"],
.field input[type="number"],
.field select {
  appearance: none;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.75rem;
  background: var(--color-surface);
  color: inherit;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.field input:focus-visible,
.field select:focus-visible {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
  outline: none;
}

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-xs);
}

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-xs);
}

.chip {
  border: none;
  border-radius: 999px;
  padding: 0.35rem 0.75rem;
  background: rgba(124, 93, 250, 0.16);
  color: inherit;
  cursor: pointer;
  font-size: 0.85rem;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--gap-md);
}

.card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: var(--gap-md);
  box-shadow: var(--shadow-soft);
  display: grid;
  gap: var(--gap-sm);
  border: 1.5px solid transparent;
  transition: transform var(--transition-base), box-shadow var(--transition-base), border var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(124, 93, 250, 0.2);
}

.card__title {
  margin: 0;
  font-size: 1.2rem;
}

.card__meta {
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.card__description {
  color: var(--color-text-muted);
  min-height: 3.5rem;
}

.card__metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--gap-xs) var(--gap-sm);
  font-size: 0.9rem;
}

.card__metrics dt {
  font-weight: 600;
}

.card__metrics dd {
  margin: 0;
  color: var(--color-text-muted);
}

.card__actions {
  display: flex;
  gap: var(--gap-xs);
}

.dataset-state {
  color: var(--color-text-muted);
}

.timeline-wrapper {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap-md);
}

.timeline {
  width: 100%;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
}

.chart-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: var(--gap-md);
  display: grid;
  gap: var(--gap-sm);
}

.chart-card svg {
  width: 100%;
  height: auto;
}

.charts-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap-md);
  display: grid;
  gap: var(--gap-md);
}

@media (min-width: 960px) {
  .charts-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .charts-grid figure:last-child {
    grid-column: 1 / -1;
  }
}

.constants-editor {
  margin-top: var(--gap-lg);
  padding: var(--gap-md);
  background: var(--color-surface-alt);
  border-radius: var(--radius-md);
  display: grid;
  gap: var(--gap-md);
}

.constants-controls {
  display: grid;
  gap: var(--gap-sm);
}

.constants-controls label {
  display: grid;
  gap: var(--gap-xs);
}

.constants-controls input[type="number"] {
  width: 140px;
}

.comparateur {
  display: grid;
  gap: var(--gap-md);
}

.comparateur__selector {
  display: grid;
  gap: var(--gap-xs);
}

.comparateur__results {
  display: grid;
  gap: var(--gap-sm);
}

.comparison-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--gap-xs);
  padding: var(--gap-xs);
  border-radius: var(--radius-xs);
  background: var(--color-surface-alt);
}

.comparison-row strong {
  font-size: 0.95rem;
}

.markdown {
  display: grid;
  gap: var(--gap-sm);
  font-size: 1rem;
  line-height: 1.65;
}

.markdown h1,
.markdown h2,
.markdown h3,
.markdown h4 {
  font-family: var(--font-serif);
  margin: var(--gap-md) 0 var(--gap-xs);
}

.markdown code {
  font-family: var(--font-mono);
  background: rgba(124, 93, 250, 0.14);
  padding: 0.15rem 0.35rem;
  border-radius: var(--radius-xs);
}

.tabs {
  display: inline-flex;
  gap: 4px;
  background: var(--color-surface);
  border-radius: 999px;
  padding: 4px;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.08);
  margin-bottom: var(--gap-md);
}

.tab {
  border: none;
  background: transparent;
  border-radius: 999px;
  padding: 0.4rem 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base);
}

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

.faq {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap-md);
  display: grid;
  gap: var(--gap-md);
}

.faq dt {
  font-weight: 700;
}

.glossary {
  list-style: none;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap-md);
  display: grid;
  gap: var(--gap-sm);
}

.site-footer {
  background: var(--color-surface);
  padding: var(--gap-xl) var(--gap-md) var(--gap-lg);
  margin-top: var(--gap-xl);
  box-shadow: inset 0 1px 0 rgba(0, 0, 0, 0.08);
}

.site-footer__meta {
  max-width: var(--max-width);
  margin: 0 auto var(--gap-md);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--gap-sm);
}

.test-runner {
  max-width: var(--max-width);
  margin: 0 auto;
  background: var(--color-surface-alt);
  padding: var(--gap-md);
  border-radius: var(--radius-md);
  display: grid;
  gap: var(--gap-sm);
}

.test-actions {
  display: flex;
  gap: var(--gap-xs);
  flex-wrap: wrap;
}

.test-report {
  min-height: 80px;
  border-radius: var(--radius-sm);
  padding: var(--gap-sm);
  background: var(--color-surface);
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.06);
  display: grid;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.9rem;
}

.modal {
  position: fixed;
  inset: 0;
  background: rgba(12, 16, 26, 0.62);
  display: grid;
  place-items: center;
  padding: var(--gap-md);
  opacity: 0;
  visibility: hidden;
  transition: opacity 200ms ease;
  z-index: 30;
}

.modal[aria-hidden="false"] {
  opacity: 1;
  visibility: visible;
}

.modal__dialog {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-hover);
  width: min(780px, 95vw);
  max-height: 86vh;
  overflow: hidden auto;
  padding: var(--gap-lg);
  display: grid;
  gap: var(--gap-md);
}

.modal__close {
  position: sticky;
  top: 0;
  justify-self: end;
  border: none;
  background: rgba(124, 93, 250, 0.16);
  color: inherit;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  font-size: 1.5rem;
  cursor: pointer;
}

.species-detail {
  display: grid;
  gap: var(--gap-md);
}

.species-detail__header {
  display: grid;
  gap: var(--gap-xs);
}

.species-detail__metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--gap-sm);
  background: var(--color-surface-alt);
  border-radius: var(--radius-md);
  padding: var(--gap-md);
}

.species-detail__metrics dt {
  font-weight: 600;
}

.species-detail__metrics dd {
  margin: 0;
}

.species-detail__calculs {
  display: grid;
  gap: var(--gap-sm);
}

.calculation-step {
  background: var(--color-surface);
  border-radius: var(--radius-sm);
  padding: var(--gap-sm);
  box-shadow: inset 0 0 0 1px rgba(124, 93, 250, 0.16);
}

.timeline-tooltip {
  pointer-events: none;
  position: absolute;
  background: var(--color-surface);
  color: var(--color-text);
  padding: 0.55rem 0.8rem;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-soft);
  font-size: 0.9rem;
  transform: translate(-50%, -100%);
  z-index: 20;
  opacity: 0;
  transition: opacity 120ms ease;
}

.timeline-tooltip[data-visible="true"] {
  opacity: 1;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

[data-reduced-motion="true"] *,
[data-reduced-motion="true"] *::before,
[data-reduced-motion="true"] *::after {
  animation-duration: 0.001s !important;
  transition-duration: 0.001s !important;
}

@media (max-width: 960px) {
  .nav-links {
    position: absolute;
    top: 68px;
    left: 16px;
    right: 16px;
    background: rgba(15, 18, 24, 0.92);
    backdrop-filter: blur(18px);
    flex-direction: column;
    padding: var(--gap-sm);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-soft);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity var(--transition-base), transform var(--transition-base);
  }

  .nav-links[data-open="true"] {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  #menuToggle {
    display: inline-flex;
  }
}

@media (min-width: 961px) {
  #menuToggle {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --transition-base: 0ms;
  }

  a::after,
  .button,
  .card {
    transition: none;
  }
}