* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: Arial, sans-serif;
  background: #f8fafc;
  color: #0f172a;
  line-height: 1.6;
}

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

.top {
  min-height: 100vh;
  color: white;
  background:
    linear-gradient(rgba(2, 6, 23, 0.74), rgba(2, 6, 23, 0.78)),
    url("https://images.unsplash.com/photo-1486262715619-67b85e0b08d3?auto=format&fit=crop&w=1600&q=80");
  background-size: cover;
  background-position: center;
  padding: 24px 6%;
}

.btn-retour-site {
  position: fixed;
  bottom: 25px;
  left: 25px;
  z-index: 9999;
  padding: 13px 22px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.85);
  color: white;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(12px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.35);
  transition: 0.25s ease;
}

.btn-retour-site:hover {
  background: #ef4444;
  transform: translateY(-3px);
  box-shadow: 0 15px 35px rgba(239, 68, 68, 0.35);
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 900;
  font-size: 1.3rem;
}

.logo span {
  color: #ef4444;
  margin-left: 4px;
}

nav div {
  display: flex;
  gap: 22px;
  color: #e2e8f0;
}

.hero {
  max-width: 820px;
  padding-top: 17vh;
}

.tag,
.title p {
  color: #ef4444;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 1px;
}

h1 {
  font-size: clamp(2.5rem, 7vw, 5.8rem);
  line-height: 0.95;
  margin: 16px 0;
}

.hero p {
  color: #e2e8f0;
  max-width: 640px;
}

.actions {
  margin-top: 28px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.btn,
button {
  display: inline-flex;
  border: none;
  padding: 14px 22px;
  border-radius: 12px;
  font-weight: 900;
  cursor: pointer;
}

.primary {
  background: #ef4444;
  color: white;
}

.secondary {
  background: white;
  color: #0f172a;
}

.section {
  width: min(1120px, 92%);
  margin: auto;
  padding: 80px 0;
}

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: -70px;
  position: relative;
}

.stats div {
  background: white;
  border-radius: 24px;
  padding: 28px;
  box-shadow: 0 20px 60px rgba(15, 23, 42, 0.14);
}

.stats strong {
  display: block;
  color: #ef4444;
  font-size: 2.4rem;
}

.title h2,
.devis h2,
.contact h2 {
  font-size: clamp(2rem, 5vw, 3.7rem);
  line-height: 1;
  margin: 8px 0 28px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.cards article {
  background: white;
  padding: 30px;
  border-radius: 24px;
  box-shadow: 0 20px 60px rgba(15, 23, 42, 0.08);
}

.cards h3 {
  color: #ef4444;
  font-size: 1.45rem;
}

.cards p {
  color: #475569;
  margin-top: 12px;
}

.devis {
  width: min(1120px, 92%);
  margin: auto;
  padding: 60px;
  border-radius: 32px;
  background: #0f172a;
  color: white;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
}

.devis p {
  color: #cbd5e1;
}

form {
  display: grid;
  gap: 14px;
}

input,
textarea {
  width: 100%;
  padding: 15px;
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.08);
  color: white;
}

textarea {
  min-height: 120px;
  resize: vertical;
}

input::placeholder,
textarea::placeholder {
  color: #cbd5e1;
}

button {
  background: #ef4444;
  color: white;
  justify-content: center;
}

.contact {
  width: min(900px, 92%);
  margin: 70px auto;
  text-align: center;
  padding: 54px 24px;
}

.contact p {
  margin-bottom: 24px;
  color: #475569;
}

footer {
  text-align: center;
  padding: 28px;
  color: #64748b;
}

/* Responsive tablette / mobile */
@media (max-width: 850px) {
  nav div {
    display: none;
  }

  .stats,
  .cards,
  .devis {
    grid-template-columns: 1fr;
  }

  .devis {
    padding: 32px 22px;
  }
}

/* Bouton retour sur mobile */
@media (max-width: 768px) {
  .btn-retour-site {
    bottom: 15px;
    left: 15px;
    padding: 11px 16px;
    font-size: 13px;
  }
}