/* ==========================================================================
   CheckIA — feuille de style unique
   Palette et typographie conservées depuis la charte existante.
   ========================================================================== */

/* --- Tokens ------------------------------------------------------------- */
:root {
  /* Couleurs héritées de la charte */
  --ink: #181b25;
  --ink-soft: #242731;
  --muted: #67676b;
  --line: #e5e7eb;
  --surface: #f5f8fc;
  --white: #fff;

  /* Accent de marque (logo) */
  --accent: #5ae9fd;
  --accent-deep: #0b6d80;
  --accent-wash: #d3f8fe;
  --blue-wash: #bfe2ff;
  --green-wash: #d9f8c0;

  /* Rythme */
  --gutter: clamp(1.25rem, 4vw, 2.5rem);
  --measure: 1200px;
  --section-y: clamp(4.5rem, 9vw, 8.5rem);
  --radius: 20px;
  --radius-lg: 28px;

  /* Élévation */
  --shadow-sm: 0 1px 2px rgb(24 27 37 / 4%), 0 2px 8px rgb(24 27 37 / 4%);
  --shadow-md: 0 2px 4px rgb(24 27 37 / 3%), 0 12px 28px rgb(24 27 37 / 7%);
  --shadow-lg: 0 4px 8px rgb(24 27 37 / 4%), 0 24px 60px rgb(24 27 37 / 10%);
  --shadow-xl: 0 8px 16px rgb(24 27 37 / 5%), 0 40px 96px rgb(24 27 37 / 14%);

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 6rem;
}

body {
  margin: 0;
  background: var(--white);
  color: var(--ink);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  font-feature-settings: "cv11", "ss01";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img, svg { display: block; max-width: 100%; height: auto; }
h1, h2, h3, p, ul { margin: 0; }
ul { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
strong { font-weight: 700; }
button { font: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--accent-deep);
  outline-offset: 3px;
  border-radius: 4px;
}

/* --- Typographie -------------------------------------------------------- */
.h1 {
  font-size: clamp(2.25rem, 1.5rem + 2.9vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.035em;
  font-weight: 700;
  text-wrap: balance;
}

.h2 {
  font-size: clamp(1.9rem, 1.15rem + 2.6vw, 3.1rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 700;
  text-wrap: balance;
}

.h3 {
  font-size: clamp(1.125rem, 1rem + 0.5vw, 1.375rem);
  line-height: 1.3;
  letter-spacing: -0.02em;
  font-weight: 650;
  text-wrap: balance;
}

.lead {
  font-size: clamp(1.05rem, 0.98rem + 0.35vw, 1.25rem);
  line-height: 1.6;
  color: var(--muted);
  text-wrap: pretty;
}

.body { color: var(--muted); text-wrap: pretty; }
.small { font-size: 0.875rem; }
.center { text-align: center; }

/* Points médians décoratifs de la charte */
em { font-style: normal; color: var(--accent-deep); }

/* --- Layout ------------------------------------------------------------- */
.wrap {
  width: 100%;
  max-width: var(--measure);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }
.section--tint { background: var(--surface); }

.stack { display: grid; gap: 1rem; }
.stack--lg { gap: clamp(1.5rem, 3vw, 2.25rem); }

.section-head {
  display: grid;
  gap: 1.15rem;
  max-width: 46rem;
  margin-inline: auto;
  margin-bottom: clamp(2.75rem, 5vw, 4.5rem);
}

/* --- Boutons ------------------------------------------------------------ */
.btn {
  --btn-bg: var(--ink);
  --btn-fg: var(--white);
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.95rem 1.7rem;
  border: 0;
  border-radius: 999px;
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-size: 0.975rem;
  font-weight: 550;
  letter-spacing: -0.01em;
  white-space: nowrap;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

/* Halo cyan de marque, révélé au survol */
.btn::after {
  content: "";
  position: absolute;
  inset: -2px;
  border-radius: inherit;
  background: radial-gradient(60% 120% at 50% 120%, var(--accent) 0%, transparent 70%);
  opacity: 0;
  z-index: -1;
  filter: blur(10px);
  transition: opacity 0.35s var(--ease);
}

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

.btn:hover::after { opacity: 0.75; }
.btn:active { transform: translateY(0); }

.btn--sm { padding: 0.7rem 1.25rem; font-size: 0.9rem; }

.btn__arrow {
  width: 1em;
  height: 1em;
  transition: transform 0.35s var(--ease);
}

.btn:hover .btn__arrow { transform: translateX(3px); }

/* --- Navigation --------------------------------------------------------- */
.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  padding-block: 0.85rem;
  background: rgb(255 255 255 / 72%);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}

.nav.is-stuck {
  border-bottom-color: var(--line);
  background: rgb(255 255 255 / 88%);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.nav__logo { height: 30px; width: auto; }

/* --- Hero --------------------------------------------------------------- */
.hero {
  position: relative;
  padding-top: clamp(8rem, 14vw, 11rem);
  padding-bottom: clamp(3rem, 6vw, 5rem);
  overflow: hidden;
  isolation: isolate;
}

/* Dégradé de fond composé des trois teintes pastel de la charte */
.hero__aura {
  position: absolute;
  inset: -20% -10% auto;
  height: 120%;
  z-index: -1;
  background:
    radial-gradient(40% 38% at 10% 10%, var(--accent-wash) 0%, transparent 64%),
    radial-gradient(38% 36% at 90% 6%, var(--blue-wash) 0%, transparent 62%),
    radial-gradient(34% 26% at 50% 88%, var(--green-wash) 0%, transparent 66%),
    linear-gradient(180deg, var(--surface) 0%, var(--white) 62%);
  opacity: 0.7;
  filter: blur(6px);
}

.hero__grid {
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(to right, rgb(24 27 37 / 4%) 1px, transparent 1px),
    linear-gradient(to bottom, rgb(24 27 37 / 4%) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(70% 55% at 50% 30%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 55% at 50% 30%, #000 0%, transparent 78%);
}

.hero__head {
  display: grid;
  gap: 1.6rem;
  justify-items: center;
  max-width: 58rem;
  margin-inline: auto;
  text-align: center;
}

.hero__sub { max-width: 44rem; }

.hero__meta {
  max-width: 42rem;
  font-size: 0.975rem;
  color: var(--muted);
}

.hero__cta { margin-top: 0.5rem; }

/* Trio de captures en perspective */
.hero__shots {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(0.75rem, 2vw, 1.5rem);
  align-items: start;
  max-width: 1080px;
  margin: clamp(3rem, 6vw, 5rem) auto 0;
  perspective: 1600px;
}

.hero__shot {
  width: 100%;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--white);
  box-shadow: var(--shadow-lg);
  transform: rotateX(6deg) translateZ(0);
  transform-origin: top center;
  transition: transform 0.6s var(--ease), box-shadow 0.6s var(--ease);
}

.hero__shot:nth-child(2) {
  margin-top: clamp(1rem, 3vw, 2.25rem);
  box-shadow: var(--shadow-xl);
}

.hero__shots:hover .hero__shot { transform: rotateX(2deg); }

/* --- Cartes problème ---------------------------------------------------- */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 17rem), 1fr));
  gap: clamp(1rem, 2vw, 1.5rem);
}

.card {
  display: grid;
  gap: 0.9rem;
  padding: clamp(1.75rem, 3vw, 2.5rem);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--white);
  box-shadow: var(--shadow-sm);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease),
    border-color 0.4s var(--ease);
}

.card:hover {
  transform: translateY(-4px);
  border-color: transparent;
  box-shadow: var(--shadow-lg);
}

.card__icon {
  display: grid;
  place-items: center;
  width: 3rem;
  height: 3rem;
  border-radius: 14px;
  background: linear-gradient(145deg, var(--accent-wash), var(--surface));
  border: 1px solid var(--line);
}

.card__icon img { width: 1.4rem; height: 1.4rem; }

/* --- Section solution --------------------------------------------------- */
.split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(2.5rem, 5vw, 4.5rem);
  align-items: center;
}

@media (min-width: 62rem) {
  .split { grid-template-columns: 1.05fr 0.95fr; }
}

.split__body { display: grid; gap: 1.5rem; }

.feature-list { display: grid; margin-top: 0.75rem; }

.feature-list__item {
  display: grid;
  gap: 0.5rem;
  padding-block: 1.4rem;
  border-top: 1px solid var(--line);
}

.feature-list__item:first-child { border-top: 0; padding-top: 0; }

.feature-list__head {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-weight: 650;
  letter-spacing: -0.015em;
}

.feature-list__head img {
  width: 1.05rem;
  height: 1.05rem;
  flex: none;
  opacity: 0.75;
}

/* Cadre produit avec halo */
.frame {
  position: relative;
  border-radius: var(--radius-lg);
  isolation: isolate;
}

.frame::before {
  content: "";
  position: absolute;
  inset: -14%;
  z-index: -1;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-wash) 0%, transparent 65%);
  opacity: 0.9;
}

.frame img {
  width: 100%;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-xl);
}

/* --- Statistiques ------------------------------------------------------- */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr));
  gap: clamp(1rem, 2vw, 1.5rem);
  align-items: stretch;
}

.stat {
  display: grid;
  align-content: start;
  gap: 0.5rem;
  padding: clamp(1.75rem, 3vw, 2.5rem);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--white);
  box-shadow: var(--shadow-sm);
}

.stat__num {
  font-size: clamp(3rem, 2rem + 4vw, 5rem);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.05em;
  background: linear-gradient(135deg, var(--ink) 25%, var(--accent-deep) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.stat--wide {
  display: grid;
  align-content: center;
  background: linear-gradient(145deg, var(--surface), var(--accent-wash));
  border-color: transparent;
}

.stats__note { margin-top: clamp(2rem, 4vw, 3rem); }

/* --- Piliers ------------------------------------------------------------ */
.pillars {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 17rem), 1fr));
  gap: clamp(1rem, 2vw, 1.5rem);
}

.pillar {
  display: grid;
  align-content: start;
  gap: 1.25rem;
  padding: clamp(1.75rem, 3vw, 2.5rem);
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}

.pillar:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }

.pillar--a { background: linear-gradient(150deg, var(--blue-wash), #eaf5ff); }
.pillar--b { background: linear-gradient(150deg, var(--green-wash), #f1fce8); }
.pillar--c { background: linear-gradient(150deg, var(--accent-wash), #ebfdff); }

.pillar__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 1.1rem;
  border-bottom: 1px solid rgb(24 27 37 / 8%);
}

.pillar__head img { width: 1.35rem; height: 1.35rem; opacity: 0.5; }
.pillar p { color: rgb(24 27 37 / 68%); }

/* --- Onglets fonctionnalités -------------------------------------------- */
.tabs {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 3vw, 2.5rem);
  align-items: start;
}

@media (min-width: 62rem) {
  .tabs { grid-template-columns: 24rem 1fr; }
}

.tabs__list { display: grid; gap: 0.5rem; }

.tab {
  display: grid;
  gap: 0.35rem;
  width: 100%;
  padding: 1.15rem 1.35rem;
  text-align: left;
  border: 1px solid transparent;
  border-radius: 16px;
  background: transparent;
  cursor: pointer;
  transition: background 0.35s var(--ease), border-color 0.35s var(--ease),
    box-shadow 0.35s var(--ease);
}

.tab:hover { background: var(--white); }

.tab[aria-selected="true"] {
  background: var(--white);
  border-color: var(--line);
  box-shadow: var(--shadow-md);
}

.tab__title {
  font-size: 1rem;
  font-weight: 650;
  letter-spacing: -0.015em;
  color: var(--muted);
  transition: color 0.35s var(--ease);
}

.tab[aria-selected="true"] .tab__title { color: var(--ink); }

.tab__desc {
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--muted);
  /* Le détail ne se déploie que sur l'onglet actif, en grand écran */
}

.tab__panels { position: relative; }

.tab__panel { display: none; }
.tab__panel.is-active { display: block; animation: panel-in 0.5s var(--ease); }

.tab__panel img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-lg);
}

@keyframes panel-in {
  from { opacity: 0; transform: translateY(10px) scale(0.995); }
  to { opacity: 1; transform: none; }
}

/* --- Appel à l'action --------------------------------------------------- */
.cta {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  margin-inline: var(--gutter);
  border-radius: clamp(24px, 4vw, 40px);
  background: var(--ink);
  color: var(--white);
}

.cta__aura {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(46% 60% at 50% 0%, rgb(90 233 253 / 26%) 0%, transparent 68%),
    radial-gradient(40% 50% at 12% 100%, rgb(191 226 255 / 14%) 0%, transparent 70%);
}

.cta__inner {
  display: grid;
  gap: clamp(2.5rem, 5vw, 4rem);
  justify-items: center;
  padding: clamp(3.5rem, 7vw, 6rem) var(--gutter) 0;
  text-align: center;
}

.cta__head { display: grid; gap: 1.1rem; max-width: 42rem; }
.cta .body { color: rgb(255 255 255 / 66%); }

.cta .btn {
  --btn-bg: var(--white);
  --btn-fg: var(--ink);
}

/* L'image porte déjà son propre cadre de navigateur aux angles transparents :
   pas de bordure ni de rayon supplémentaires, seulement un halo. */
.cta__shot {
  width: min(100%, 62rem);
  filter: drop-shadow(0 -6px 50px rgb(90 233 253 / 18%));
}

/* --- Pied de page ------------------------------------------------------- */
.footer { padding-block: clamp(2.5rem, 5vw, 4rem) 2rem; }

.footer__top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding-bottom: 1.75rem;
  border-bottom: 1px solid var(--line);
}

.footer__logo { height: 28px; width: auto; }

.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.75rem;
  color: var(--muted);
}

.footer__links a { transition: color 0.25s var(--ease); }
.footer__links a:hover { color: var(--ink); }

.footer__bottom { padding-top: 1.5rem; color: var(--muted); }

/* --- Animations d'apparition -------------------------------------------- */
/* Contenu visible par défaut : si le JS échoue, rien ne disparaît. */
.reveal { opacity: 1; }

html.js .reveal {
  opacity: 0;
  transform: translateY(18px);
}

html.js .reveal.is-in {
  opacity: 1;
  transform: none;
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  transition-delay: var(--delay, 0ms);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  html.js .reveal,
  html.js .reveal.is-in {
    opacity: 1;
    transform: none;
    transition: none;
  }

  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* --- Petits écrans ------------------------------------------------------ */
@media (max-width: 40rem) {
  .hero__shots { grid-template-columns: 1fr; max-width: 24rem; }
  .hero__shot, .hero__shots:hover .hero__shot { transform: none; }
  .hero__shot:nth-child(2) { margin-top: 0; }
  .nav__logo { height: 26px; }
}

/* --- Page 404 ----------------------------------------------------------- */
.notfound {
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 1.5rem;
  min-height: 100vh;
  padding: var(--gutter);
  text-align: center;
}