:root {
    color-scheme: light;
    --bg: #f3f6fb;
    --card: #ffffff;
    --text: #172033;
    --muted: #667085;
    --border: #d8dee9;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --danger-bg: #fff1f2;
    --danger: #9f1239;
    --warn-bg: #fff7ed;
    --warn: #9a3412;
}
* { box-sizing: border-box; }
html, body { min-height: 100%; }
body {
    margin: 0;
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: radial-gradient(circle at 20% 0%, #e6efff 0, transparent 38%), var(--bg);
    color: var(--text);
}
.auth-shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 28px 16px;
}
.auth-card {
    width: min(100%, 480px);
    background: var(--card);
    border: 1px solid rgba(216, 222, 233, .9);
    border-radius: 18px;
    padding: 30px;
    box-shadow: 0 18px 60px rgba(16, 24, 40, .10);
}
.auth-brand {
    width: 52px;
    height: 52px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    background: #eff6ff;
    font-size: 27px;
    margin-bottom: 20px;
}
.eyebrow {
    margin: 0 0 7px;
    color: var(--primary);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: .12em;
}
h1 { margin: 0; font-size: clamp(26px, 5vw, 34px); letter-spacing: -.03em; }
.lead { color: var(--muted); line-height: 1.6; margin: 10px 0 22px; }
form { display: grid; gap: 9px; }
label { margin-top: 8px; font-weight: 700; font-size: 14px; }
input {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 13px;
    font: inherit;
    color: var(--text);
    outline: none;
    transition: border-color .15s, box-shadow .15s;
}
input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37, 99, 235, .12); }
.field-help, .footer-note { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.5; }
.primary {
    margin-top: 14px;
    border: 0;
    border-radius: 10px;
    padding: 12px 16px;
    background: var(--primary);
    color: white;
    font: inherit;
    font-weight: 800;
    cursor: pointer;
}
.primary:hover { background: var(--primary-hover); }
.primary:disabled { opacity: .55; cursor: not-allowed; }
.notice { border-radius: 10px; padding: 12px 13px; margin: 0 0 16px; font-size: 13px; line-height: 1.5; }
.notice.error { background: var(--danger-bg); color: var(--danger); border: 1px solid #fecdd3; }
.notice.warning { background: var(--warn-bg); color: var(--warn); border: 1px solid #fed7aa; }
.security-points { display: grid; gap: 7px; margin-top: 22px; color: var(--muted); font-size: 12px; }
.footer-note { text-align: center; margin-top: 18px; }
@media (max-width: 520px) {
    .auth-card { padding: 23px 18px; border-radius: 14px; }
}