:root {
    --ink:#14213d; --muted:#667085; --surface:#fff; --bg:#f5f7fb;
    --primary:#635bff; --primary-dark:#4b44d1; --accent:#14b8a6;
    --border:#e6e9f0; --danger:#b42318; --danger-bg:#fef3f2;
    --shadow:0 24px 70px rgba(20,33,61,.10); --radius:24px;
}
*{box-sizing:border-box}
html{min-width:320px}
body{margin:0;min-height:100vh;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--ink);background:radial-gradient(circle at 15% 10%,rgba(99,91,255,.12),transparent 32rem),radial-gradient(circle at 90% 85%,rgba(20,184,166,.10),transparent 28rem),var(--bg)}
.auth-shell{width:min(100% - 24px,520px);min-height:100vh;margin:auto;display:grid;place-items:center;padding:24px 0}
.auth-card{width:100%;padding:clamp(28px,6vw,54px);background:rgba(255,255,255,.92);border:1px solid rgba(230,233,240,.9);border-radius:var(--radius);box-shadow:var(--shadow);backdrop-filter:blur(18px)}
.brand-mark{width:52px;height:52px;display:grid;place-items:center;border-radius:16px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff;font-weight:800;font-size:24px}
.eyebrow{margin:22px 0 8px;color:var(--primary);font-weight:750;letter-spacing:.08em;text-transform:uppercase;font-size:12px}
h1{margin:0;font-size:clamp(2rem,7vw,3.1rem);letter-spacing:-.04em}
.auth-copy{margin:12px 0 28px;color:var(--muted);line-height:1.6}
label{display:block;margin:18px 0 8px;font-size:.9rem;font-weight:700}
input{width:100%;padding:14px 15px;border:1px solid var(--border);border-radius:13px;background:#fff;color:var(--ink);font:inherit;outline:none}
input:focus{border-color:var(--primary);box-shadow:0 0 0 4px rgba(99,91,255,.12)}
button{width:100%;margin-top:24px;padding:14px 18px;border:0;border-radius:13px;background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;font:inherit;font-weight:750;cursor:pointer}
button:hover{filter:brightness(.98)}
.alert{padding:12px 14px;border-radius:12px;background:var(--danger-bg);color:var(--danger);font-size:.92rem}
.security-note{margin:22px 0 0;color:var(--muted);font-size:.78rem;line-height:1.5;text-align:center}