:root {
  --bg-a: #f3efe8;
  --bg-b: #dce6f0;
  --ink: #102330;
  --muted: #516474;
  --card: #ffffffd9;
  --line: #cbdae7;
  --btn: #115d7b;
  --btn-hover: #0c4860;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--ink);
  background: radial-gradient(circle at top right, var(--bg-b), var(--bg-a));
}

.shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.panel {
  width: min(720px, 100%);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 28px;
  box-shadow: 0 18px 45px #1023301a;
}

.panel-header h1 {
  margin: 0 0 8px;
  font-size: clamp(1.45rem, 2.6vw, 2rem);
}

.eyebrow {
  margin: 0 0 10px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--muted);
  font-size: 0.78rem;
}

.subtitle {
  margin: 0;
  color: var(--muted);
}

.row {
  margin-top: 22px;
  display: grid;
  grid-template-columns: 1fr 2fr auto;
  gap: 10px;
  align-items: center;
}

label {
  font-weight: 600;
}

input,
button {
  height: 42px;
  border-radius: 10px;
  border: 1px solid var(--line);
  font: inherit;
}

input {
  padding: 0 12px;
  background: #fff;
}

button {
  padding: 0 14px;
  background: var(--btn);
  color: #fff;
  cursor: pointer;
  border-color: transparent;
  transition: background 0.18s ease;
}

button:hover {
  background: var(--btn-hover);
}

.actions {
  margin-top: 14px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.output {
  margin-top: 20px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #f8fbff;
  padding: 14px;
}

.output h2 {
  margin: 0 0 10px;
  font-size: 0.95rem;
  color: var(--muted);
}

pre {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-word;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.88rem;
}

@media (max-width: 640px) {
  .panel {
    padding: 20px;
  }

  .row {
    grid-template-columns: 1fr;
  }

  button {
    width: 100%;
  }
}