:root {
  --encre: #1f2933;
  --doux: #52606d;
  --fond: #ffffff;
  --trait: #d9dee4;
  --accent: #c86d39;
  --accent-fonce: #a85a2e;
  --erreur: #b42318;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.5;
  color: var(--encre);
  background: var(--fond);
}

main { max-width: 640px; margin: 0 auto; padding: 24px 20px 48px; }

.logo {
  display: inline-block;
  font-weight: 800;
  font-size: 22px;
  letter-spacing: 0.04em;
  color: var(--encre);
  text-decoration: none;
  margin-bottom: 28px;
}

h1 { font-size: 30px; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 20px; margin: 32px 0 8px; }
.sous-titre { color: var(--doux); margin: 0 0 28px; }

p, li { text-align: justify; }

form { display: grid; gap: 18px; }
.groupe { display: grid; gap: 18px; }

label { display: grid; gap: 6px; font-weight: 600; }
label span.obl { color: var(--accent); }

input[type="text"], input[type="email"], input[type="tel"], textarea {
  width: 100%;
  font: inherit;
  font-weight: 400;
  color: inherit;
  padding: 12px 14px;
  border: 1px solid var(--trait);
  border-radius: 10px;
  background: #fff;
}
textarea { min-height: 110px; resize: vertical; }
input:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent); }

.case { display: flex; gap: 12px; align-items: flex-start; font-weight: 400; }
.case input { width: 22px; height: 22px; margin: 2px 0 0; flex: none; accent-color: var(--accent); }

.piege { position: absolute; left: -10000px; width: 1px; height: 1px; overflow: hidden; }

button {
  font: inherit;
  font-weight: 700;
  color: #fff;
  background: var(--accent);
  border: 0;
  border-radius: 10px;
  padding: 15px 20px;
  min-height: 52px;
  cursor: pointer;
}
button:hover { background: var(--accent-fonce); }
button:disabled { opacity: 0.6; cursor: wait; }

.message-erreur { color: var(--erreur); font-weight: 600; margin: 0; }
.merci { font-size: 19px; padding: 20px; border-left: 4px solid var(--accent); background: #faf6f3; }

.pied { margin-top: 8px; font-size: 15px; color: var(--doux); }
.pied a, main a { color: var(--accent-fonce); }

footer { max-width: 640px; margin: 0 auto; padding: 0 20px 32px; font-size: 14px; color: var(--doux); }
footer a { color: var(--doux); }

@media (min-width: 640px) {
  .groupe.deux { grid-template-columns: 1fr 1fr; }
}