/* ==========================================================================
   PANOSTEO — Layout : conteneur, sections, en-tête, tiroir, hero, pied de page
   ========================================================================== */

.po-container {
  width: min(100% - 2 * var(--po-gutter), var(--po-container));
  margin-inline: auto;
}
.po-container--narrow { max-width: var(--po-container-narrow); }
.po-container--wide { width: min(100% - 2 * var(--po-gutter), var(--po-container-wide)); }

/* ---- Sections ---- */
.po-section {
  position: relative;
  padding-block: var(--po-section-y);
  background: var(--po-bg);
  color: var(--po-text);
}
.po-section--alt {
  --po-bg: var(--po-spongieux);
  --po-surface-2: var(--po-os);
  border-top: 1px solid var(--po-trame);
  border-bottom: 1px solid var(--po-trame);
}
.po-section--structure {
  --po-bg: var(--po-corticale-pale);
  --po-surface-2: var(--po-os);
}

.po-section__head {
  max-width: var(--po-container-narrow);
  margin-bottom: clamp(2.5rem, 2rem + 2vw, 4rem);
  display: grid;
  gap: var(--po-s-4);
}
.po-section__head--center {
  margin-inline: auto;
  text-align: center;
  justify-items: center;
}
.po-section__head .po-lead { margin-top: var(--po-s-2); }
.po-section__foot { margin-top: clamp(2rem, 1.5rem + 2vw, 3rem); }

/* ---- Grilles ---- */
.po-grid {
  display: grid;
  gap: var(--po-s-5);
  grid-template-columns: 1fr;
}
@media (min-width: 760px) {
  .po-grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .po-grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .po-grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1024px) {
  .po-grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.po-split {
  display: grid;
  gap: var(--po-s-7);
  align-items: center;
}
@media (min-width: 1024px) {
  .po-split { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: var(--po-s-8); }
}

/* ---- En-tête ---- */
.po-header {
  position: sticky;
  top: 0;
  z-index: var(--po-z-header);
  height: var(--po-header-h);
  background: var(--po-bg);
  color: var(--po-text);
  border-bottom: 1px solid transparent;
  transition: background var(--po-t-base) var(--po-ease), box-shadow var(--po-t-base) var(--po-ease), height .3s var(--po-ease), border-color var(--po-t-base) var(--po-ease);
}
.po-header:not(.po-dark) { border-bottom-color: var(--po-border); }
.po-header.is-scrolled { height: 72px; }
.po-header.is-scrolled:not(.po-dark) { box-shadow: var(--po-shadow-1); }
.po-header__inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--po-s-5);
}
.po-brand {
  display: inline-flex;
  align-items: center;
  padding: var(--po-s-2) 0;
  text-decoration: none;
  flex-shrink: 0;
}
.po-brand img {
  height: 36px;
  width: auto;
  transition: height .3s var(--po-ease);
}
.po-header.is-scrolled .po-brand img { height: 32px; }
.po-brand__dark, .po-brand__mark, .po-brand__mark-dark { display: none; }
.po-header.po-dark .po-brand__light { display: none; }
.po-header.po-dark .po-brand__dark { display: block; }
@media (max-width: 639px) {
  .po-brand__light, .po-brand__dark { display: none !important; }
  .po-brand__mark { display: block; }
  .po-header.po-dark .po-brand__mark { display: none; }
  .po-header.po-dark .po-brand__mark-dark { display: block; }
}

.po-nav { display: none; }
.po-nav__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: clamp(1rem, 1.6vw, 1.75rem);
}
.po-nav__link {
  font-weight: 500;
  font-size: .9375rem;
  color: var(--po-text);
  text-decoration: none;
  padding: var(--po-s-2) 0;
  background-image: linear-gradient(currentColor, currentColor);
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0 1px;
  transition: background-size var(--po-t-base) var(--po-ease), color var(--po-t-fast);
}
.po-nav__link:hover,
.po-nav__link[aria-current="true"] { background-size: 100% 1px; }
.po-header__actions {
  display: flex;
  align-items: center;
  gap: var(--po-s-4);
}
.po-header .po-header__cta { display: none; }
@media (min-width: 760px) {
  .po-header .po-header__cta { display: inline-flex; }
}
@media (min-width: 1024px) {
  .po-nav { display: block; }
  .po-burger { display: none; }
}

/* Bascule de langue */
.po-lang {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--po-border-strong);
  border-radius: var(--po-r-pill);
  padding: 2px;
  font-family: var(--po-font-mono);
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .08em;
}
.po-lang__btn {
  padding: .3rem .6rem;
  border-radius: var(--po-r-pill);
  color: var(--po-text-2);
  transition: background var(--po-t-fast), color var(--po-t-fast);
}
.po-lang__btn[aria-pressed="true"] {
  background: var(--po-text);
  color: var(--po-bg);
}
.po-lang__btn:focus-visible { outline-offset: 1px; }

/* Bouton burger */
.po-burger {
  position: relative;
  width: 44px;
  height: 44px;
  border-radius: var(--po-r-2);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.po-burger__bar,
.po-burger__bar::before,
.po-burger__bar::after {
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform .3s var(--po-ease), background .2s;
}
.po-burger__bar { position: relative; }
.po-burger__bar::before, .po-burger__bar::after { content: ""; position: absolute; left: 0; }
.po-burger__bar::before { top: -7px; }
.po-burger__bar::after { top: 7px; }
.po-burger[aria-expanded="true"] .po-burger__bar { background: transparent; }
.po-burger[aria-expanded="true"] .po-burger__bar::before { transform: translateY(7px) rotate(45deg); }
.po-burger[aria-expanded="true"] .po-burger__bar::after { transform: translateY(-7px) rotate(-45deg); }

/* Filet de progression (la ligne de sol qui se remplit au fil de la lecture) */
.po-progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 100%;
  height: 2px;
  background: var(--po-accent);
  transform: scaleX(0);
  transform-origin: left;
  z-index: var(--po-z-progress);
}

/* ---- Tiroir mobile ---- */
.po-drawer {
  position: fixed;
  inset: 0;
  z-index: var(--po-z-drawer);
  visibility: hidden;
  transition: visibility 0s var(--po-t-base);
}
.po-drawer.is-open { visibility: visible; transition-delay: 0s; }
.po-drawer__backdrop {
  position: absolute;
  inset: 0;
  background: rgb(var(--po-encre-rgb) / .4);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  opacity: 0;
  transition: opacity var(--po-t-base) var(--po-ease);
}
.po-drawer.is-open .po-drawer__backdrop { opacity: 1; }
.po-drawer__panel {
  position: absolute;
  top: 0;
  right: 0;
  height: 100%;
  width: min(88vw, 360px);
  background: var(--po-os);
  color: var(--po-encre);
  padding: calc(var(--po-header-h) + var(--po-s-4)) var(--po-s-6) var(--po-s-6);
  display: flex;
  flex-direction: column;
  gap: var(--po-s-6);
  overflow-y: auto;
  transform: translateX(100%);
  transition: transform var(--po-t-base) var(--po-ease);
  box-shadow: var(--po-shadow-3);
}
.po-drawer.is-open .po-drawer__panel { transform: none; }
.po-drawer__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--po-s-2);
}
.po-drawer__link {
  display: block;
  padding: var(--po-s-3) 0;
  font-family: var(--po-font-display);
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--po-corticale);
  text-decoration: none;
  border-bottom: 1px solid var(--po-trame);
}
.po-drawer__link[aria-current="true"] { border-bottom-color: var(--po-mineral); }
.po-drawer__footer {
  margin-top: auto;
  display: grid;
  gap: var(--po-s-4);
}
body.has-drawer { overflow: hidden; }
@media (min-width: 1024px) { .po-drawer { display: none; } }

/* ---- Hero ---- */
.po-hero {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  min-height: min(calc(100svh - var(--po-header-h)), 860px);
  display: flex;
  align-items: center;
  padding-block: clamp(2.5rem, 1.5rem + 3vw, 4.5rem) clamp(4rem, 3rem + 4vw, 6.5rem);
}
.po-hero__field {
  position: absolute;
  inset: 0;
  z-index: var(--po-z-field);
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 1.2s var(--po-ease);
  pointer-events: none;
}
.po-hero__field.is-drawn { opacity: 1; }
.po-hero::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 120px;
  background: linear-gradient(to bottom, transparent, var(--po-corticale-deep));
  z-index: var(--po-z-field);
  pointer-events: none;
}
.po-hero__inner {
  position: relative;
  z-index: var(--po-z-content);
  display: grid;
  gap: var(--po-s-8);
  align-items: center;
}
.po-hero__copy { display: grid; gap: var(--po-s-4); max-width: 640px; }
.po-hero__copy > .po-hero__lead { margin-top: var(--po-s-2); }
.po-hero__copy > .po-hero__actions { margin-top: var(--po-s-2); }
.po-hero__title { font-size: var(--po-fs-display); line-height: 1.05; letter-spacing: -.015em; }
.po-hero__visual {
  position: relative;
  width: 100%;
  max-width: 520px;
  margin-inline: auto;
}
.po-hero__kws {
  list-style: none;
  margin: var(--po-s-2) 0 0;
  padding: 0;
  display: grid;
  gap: var(--po-s-3);
}
@media (min-width: 560px) {
  .po-hero__kws { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1024px) {
  .po-hero__inner { grid-template-columns: minmax(0, 6fr) minmax(0, 6fr); }
  .po-hero__visual { max-width: none; }
}

/* ---- Clôture (section contact, sombre) ---- */
.po-closing { overflow: hidden; }
.po-closing__actions { justify-content: center; }
.po-closing .po-note { margin-inline: auto; margin-top: var(--po-s-4); }
.po-closing__mark {
  margin-top: clamp(3rem, 2rem + 4vw, 5rem);
  display: flex;
  justify-content: center;
}
.po-closing__mark svg {
  height: 56px;
  width: auto;
  display: block;
}

/* ---- Pied de page ---- */
.po-footer {
  padding-block: var(--po-s-8) var(--po-s-6);
  border-top: 1px solid var(--po-border);
  font-size: var(--po-fs-small);
}
.po-footer__top {
  display: grid;
  gap: var(--po-s-7);
}
.po-footer__brand img { height: 40px; width: auto; }
.po-footer__brand p { margin-top: var(--po-s-4); color: var(--po-text-2); max-width: 36ch; }
.po-footer__cols {
  display: grid;
  gap: var(--po-s-6);
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}
.po-footer__col h4 {
  font-family: var(--po-font-mono);
  font-size: var(--po-fs-cartouche);
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--po-text-2);
  margin-bottom: var(--po-s-3);
}
.po-footer__col ul { list-style: none; margin: 0; padding: 0; display: grid; gap: var(--po-s-2); }
.po-footer__col a { color: var(--po-text); text-decoration: none; }
.po-footer__col a:hover { text-decoration: underline; }
.po-footer__disclaimer {
  margin-top: var(--po-s-7);
  padding-top: var(--po-s-5);
  border-top: 1px solid var(--po-border);
  color: var(--po-text-2);
  max-width: 80ch;
}
.po-footer__legal {
  margin-top: var(--po-s-5);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--po-s-3);
  color: var(--po-text-2);
}
@media (min-width: 760px) {
  .po-footer__top { grid-template-columns: minmax(0, 1fr) minmax(0, 2fr); align-items: start; }
}

/* ---- Pages secondaires (légales, 404) ---- */
.po-page { padding-block: clamp(3rem, 2rem + 4vw, 6rem); }
.po-prose { max-width: 72ch; display: grid; gap: var(--po-s-4); }
.po-prose h2 { margin-top: var(--po-s-6); font-size: var(--po-fs-h3); font-family: var(--po-font-display); }
.po-prose h3 { margin-top: var(--po-s-4); }
.po-prose ul { padding-left: 1.25em; }