:root {
  color-scheme: light;
  font: 16px/1.5 system-ui, sans-serif;
  color: #22231f;
  background: #f4f3ef;
  --line: #d4d2c9;
  --quiet: #565951;
  --ink: #fdfcf9;
  --green: #23463b;
}
*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; }
main { width: min(100% - 2.5rem, 39rem); margin: clamp(2rem, 10vh, 6rem) auto 2.5rem; }
.masthead {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: .3rem 1.2rem;
  border-top: 2px solid #292c26; padding-top: .7rem;
  color: var(--quiet); font: 600 .73rem/1.5 ui-monospace, Consolas, monospace;
  letter-spacing: .075em;
}
.masthead span:first-child { color: var(--green); }
h1 { margin: 1.85rem 0 .45rem; font-size: clamp(1.7rem, 5.8vw, 2.55rem); line-height: 1.15; letter-spacing: -.04em; }
h1 code { font-size: .92em; }
code, output, #new-address { font-family: ui-monospace, Consolas, monospace; }
.intro { margin: 0 0 1.6rem; color: var(--quiet); }
form { padding: clamp(1rem, 4vw, 1.55rem); border: 1px solid var(--line); border-radius: 5px; background: var(--ink); }
label, .label { display: block; margin: 0 0 .38rem; font-size: .88rem; font-weight: 650; }
input, button, output { font: inherit; }
input[type=file], input[type=text], output {
  display: block; width: 100%; min-width: 0; min-height: 2.8rem; border: 1px solid #aaa99f; border-radius: 4px;
}
input[type=file] { padding: .35rem; background: #fff; font-size: .86rem; }
input::file-selector-button { margin-right: .6rem; padding: .42rem .65rem; border: 0; border-radius: 2px; background: #ecece4; color: #22231f; font: inherit; cursor: pointer; }
input[type=text], output { padding: .6rem .7rem; font-family: ui-monospace, Consolas, monospace; }
output { background: #f1f0ea; border-color: var(--line); }
input::placeholder { color: #686b63; }
.hint { margin: .4rem 0 0; font-size: .82rem; color: var(--quiet); }
.address-row { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: .85rem; margin-top: 1.25rem; }
.actions { margin-top: 1.3rem; }
button {
  display: inline-flex; align-items: center; justify-content: space-between; gap: 1.3rem;
  min-height: 2.8rem; padding: .6rem .95rem; border: 1px solid transparent; border-radius: 4px;
  background: var(--green); color: white; font-weight: 650; cursor: pointer;
}
button:hover:not(:disabled) { background: #192f28; }
button:disabled { background: #e4e5dc; color: #555a50; cursor: default; }
:focus-visible { outline: 2px solid #316958; outline-offset: 3px; }
[aria-invalid=true] { border-color: #a03627 !important; }
#feedback { margin: .65rem 0 0; color: var(--green); font-size: .88rem; }
#feedback:empty { display: none; }
#feedback[data-error] { color: #8c291f; }
footer { padding-top: .9rem; font-size: .81rem; color: var(--quiet); }
@media (max-width: 370px) { .address-row { grid-template-columns: 1fr; } button { width: 100%; } }