:root { font-family: system-ui, -apple-system, "Segoe UI", sans-serif; color: #13263b; background: #f4f7fb; }
* { box-sizing: border-box; }
body { margin: 0; }
.shell { width: min(100% - 32px, 680px); margin: 0 auto; padding: 48px 0 72px; }
header { margin: 0 0 24px; }
.eyebrow { margin: 0 0 10px; color: #3976b9; font-size: .78rem; font-weight: 700; letter-spacing: .11em; }
h1 { margin: 0; font-size: clamp(2rem, 6vw, 3rem); }
h2 { margin-top: 0; font-size: 1.2rem; }
.intro { color: #526579; line-height: 1.6; }
.card { margin: 16px 0; padding: 24px; border: 1px solid #dfe7f0; border-radius: 16px; background: #fff; box-shadow: 0 8px 30px rgba(22, 57, 91, .07); }
li, .note p { line-height: 1.7; }
button { width: 100%; margin-top: 12px; padding: 13px 18px; border: 0; border-radius: 9px; background: #1769b0; color: white; font: inherit; font-weight: 700; cursor: pointer; }
button:disabled { opacity: .6; cursor: progress; }
button.secondary { background: #e8f0fa; color: #15528c; }
.status { min-height: 1.5em; margin: 18px 0 0; color: #28633e; line-height: 1.5; }
.status.error { color: #a52525; }
textarea { width: 100%; min-height: 128px; padding: 12px; border: 1px solid #b9c8d8; border-radius: 8px; resize: vertical; font: .76rem ui-monospace, monospace; }
.hidden { display: none; }