*{box-sizing:border-box}
body{margin:0;min-height:100vh;display:grid;place-items:center;padding:16px;
  background:linear-gradient(115deg,#103c82,#1d56a3);
  font:15px/1.5 Inter,system-ui,-apple-system,"Segoe UI",sans-serif;color:#152238}
.loginBox{width:100%;max-width:380px;background:#fff;border-radius:18px;padding:28px 24px;
  box-shadow:0 25px 80px rgba(10,30,65,.3)}
.mark{width:48px;height:48px;border-radius:14px;background:#123f86;color:#fff;
  display:grid;place-items:center;font-weight:800;font-size:20px;margin-bottom:12px}
h1{font-size:22px;margin:0}
.sub{margin:4px 0 18px;color:#68758a;font-size:14px}
label{display:block;font-size:12px;font-weight:700;color:#536177;margin:12px 0 5px}
input{width:100%;height:44px;border:1px solid #dce4ef;border-radius:10px;padding:0 12px;font:inherit;outline:none}
input:focus{border-color:#77a5ed;box-shadow:0 0 0 3px rgba(37,99,235,.12)}
button{width:100%;height:46px;margin-top:20px;border:0;border-radius:10px;background:#2563eb;
  color:#fff;font:inherit;font-weight:700;cursor:pointer}
button:hover{filter:brightness(.95)}
.alert{background:#ffebeb;color:#b93b3b;border:1px solid #f5c2c2;border-radius:10px;
  padding:10px 12px;font-size:14px}