* { box-sizing: border-box; }
body {
    font-family: Arial, Helvetica, sans-serif;
    background: #f5f6fa;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
}
.card {
    background: #fff;
    width: 420px;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}
h1 { font-size: 22px; margin-bottom: 6px; color: #1f2937; }
p.sub { color: #6b7280; margin-top: 0; margin-bottom: 24px; }
label { font-weight: bold; font-size: 14px; color: #1f2937; display: block; margin-bottom: 6px; }
input[type=text], input[type=password], input[type=email] {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 14px;
    margin-bottom: 18px;
}
button.btn-primary {
    width: 100%;
    padding: 12px;
    background: #0066ff;
    border: none;
    color: #fff;
    font-weight: bold;
    border-radius: 6px;
    cursor: pointer;
    font-size: 15px;
}
button.btn-primary:hover { background: #0066ff; }
.error-box {
    background: #fee2e2;
    color: #0066ff;
    padding: 10px 14px;
    border-radius: 6px;
    font-size: 13px;
    margin-bottom: 18px;
}