* { box-sizing: border-box; }
body { margin:0; font-family:Arial,Helvetica,sans-serif; background:#f3f7fa; color:#17324d; }
.page { max-width:1100px; margin:0 auto; min-height:100vh; display:flex; flex-direction:column; }
.app-header { display:flex; align-items:center; justify-content:space-between; gap:20px; background:#0f4c75; padding:18px 28px; border-radius:0 0 14px 14px; box-shadow:0 2px 10px rgba(0,0,0,.08); }
.brand-area { display:flex; align-items:center; gap:18px; width:100%; }
.app-logo { width:min(360px,55vw); height:auto; display:block; }
.brand-area .title { margin-left:auto; font-size:36px; font-weight:700; color:#fff; }
main { padding:24px; flex:1; }
.card { background:#fff; border-radius:14px; padding:24px; margin-bottom:18px; box-shadow:0 3px 12px rgba(0,0,0,.07); }
.top-layout { display:grid; grid-template-columns:1.6fr 1fr 1fr; gap:18px; }
h2 { margin:0 0 20px; font-size:22px; }
.grid { display:grid; grid-template-columns:repeat(3,minmax(0,1fr)); gap:18px; }
label { font-weight:600; font-size:15px; display:block; }
input, select { width:100%; margin-top:8px; padding:12px 13px; border:1px solid #b9c7d3; border-radius:8px; font-size:16px; background:#fff; color:#17324d; }
input:focus, select:focus { outline:2px solid #76a9c8; border-color:#0f4c75; }
button { margin-top:22px; width:100%; padding:14px; border:0; border-radius:8px; background:#0f4c75; color:#fff; font-size:17px; font-weight:700; cursor:pointer; }
button:hover { filter:brightness(1.08); }
.message { min-height:24px; margin-top:12px; font-size:14px; font-weight:600; }
.message.success { color:#26734d; }
.message.danger { color:#c40000; }
.conversion-grid { display:grid; grid-template-columns:1fr 1fr; gap:12px; align-items:end; }
.conversion-result, .altitude-box, .pressure-box { border:1px solid #d6e0e7; border-radius:10px; padding:13px; background:#f8fbfd; margin-top:8px; }
.conversion-result span, .altitude-box span, .pressure-box span { display:block; font-size:13px; color:#5c6e7d; }
.conversion-result strong, .altitude-box strong, .pressure-box strong { display:block; margin-top:7px; font-size:22px; color:#0f4c75; }
.altitude-box { margin-top:18px; }
.pressure-box { margin-top:10px; }
.small-note { font-size:12px; color:#5b6a75; line-height:1.45; margin:12px 0 0; }
.outputs { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:16px; }
.output-box { border:1px solid #d6e0e7; border-radius:10px; padding:18px; background:#f8fbfd; }
.output-box.wide { grid-column:1/-1; }
.output-box span { display:block; font-size:14px; color:#5c6e7d; }
.output-box strong { display:inline-block; margin-top:8px; font-size:28px; color:#0f4c75; }
.output-box small { margin-left:7px; font-size:13px; color:#5c6e7d; }
.note { font-size:13px; color:#5b6a75; line-height:1.5; margin:4px 4px 18px; }
footer { text-align:center; padding:18px; color:#607383; font-size:13px; }
@media (max-width:900px) {
  .top-layout { grid-template-columns:1fr; }
}
@media (max-width:700px) {
  .app-header { justify-content:center; }
  .brand-area { flex-direction:column; gap:10px; }
  .app-logo { width:min(340px,90vw); }
  .brand-area .title { margin-left:0; text-align:center; }
}
@media (max-width:650px) {
  main { padding:16px; }
  .grid,.outputs,.conversion-grid { grid-template-columns:1fr; }
  .output-box.wide { grid-column:auto; }
}

.secondary-button{margin-top:12px;background:#e8f0f5;color:#0f4c75;font-size:13px;padding:9px 12px}