html {
    color-scheme: light;
}

body {
    min-height: 100vh;
    margin: 0;
    display: grid;
    place-items: center;
    background: #f8fafc;
    color: #0f172a;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    line-height: 1.5;
}

main, .card {
    width: min(100% - 2rem, 34rem);
    box-sizing: border-box;
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 1rem;
    box-shadow: 0 1rem 2rem rgba(15, 23, 42, 0.08);
    padding: 2rem;
}

.shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 2rem;
    box-sizing: border-box;
}

h1 { margin: 0 0 .35rem; font-size: 2rem; }
p { color: #475569; }
label { display: block; margin: 1rem 0 .35rem; font-weight: 700; }
input[type="text"], input[type="email"], input[type="password"] {
    width: 100%; box-sizing: border-box; border: 1px solid #cbd5e1; border-radius: .65rem; padding: .75rem; font: inherit;
}
.checkbox-row { display: flex; gap: .5rem; align-items: center; margin-top: 1rem; }
.checkbox-row label { margin: 0; font-weight: 500; }
button, .button, .button-link {
    display: inline-flex; align-items: center; justify-content: center; min-height: 2.5rem; border: 0; border-radius: .65rem; padding: 0 1rem; background: #0f172a; color: #fff; font: inherit; font-weight: 700; text-decoration: none; cursor: pointer;
}
form > button { width: 100%; margin-top: 1.25rem; padding: .85rem 1rem; font-weight: 800; }
a { color: #1d4ed8; }
.alert, .notice { border-radius: .65rem; padding: .8rem 1rem; margin: 1rem 0; }
.alert ul, .notice ul { margin: 0; padding-left: 1.2rem; }
.alert-danger, .notice.error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-success, .notice:not(.error) { background: #ecfdf5; color: #065f46; border: 1px solid #bbf7d0; }
.alert-info { background: #eff6ff; color: #1e40af; }
.secondary-links, .actions { display: flex; flex-wrap: wrap; justify-content: center; gap: .75rem; margin-top: 1rem; text-align: center; }
.button-muted { background: #f1f5f9; color: #0f172a; }
.muted, .help-text { color: #64748b; }
.help-text { display: block; margin-top: .4rem; font-size: .925rem; }
.password-strength-meter { margin-top: .75rem; }
.password-strength-track { height: .5rem; overflow: hidden; border-radius: 999px; background: #e2e8f0; }
.password-strength-bar { display: block; width: 0; height: 100%; background: #0f172a; transition: width .2s ease; }
.password-strength-text { margin: .4rem 0 0; }
@media (max-width: 40rem) { main, .card { padding: 1.5rem; } .shell { padding: 1rem; } }