* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif; background: linear-gradient(135deg, #2b6cb0 0%, #1a365d 100%); min-height: 100vh; display: flex; align-items: center; justify-content: center; color: #2d3748; padding: 20px; }
.login-card { background: #fff; width: 100%; max-width: 380px; padding: 40px 32px; border-radius: 16px; box-shadow: 0 20px 60px rgba(0,0,0,0.2); }
.brand { text-align: center; margin-bottom: 28px; }
.logo { width: 64px; height: 64px; margin: 0 auto 16px; background: linear-gradient(135deg, #2b6cb0, #4299e1); color: #fff; font-weight: 800; font-size: 22px; border-radius: 16px; display: flex; align-items: center; justify-content: center; }
.brand h1 { font-size: 18px; margin-bottom: 6px; color: #1a202c; }
.brand p { font-size: 13px; color: #718096; }
form label { display: block; margin-bottom: 16px; }
form label span { display: block; font-size: 13px; color: #4a5568; margin-bottom: 6px; font-weight: 500; }
form input { width: 100%; padding: 10px 12px; font-size: 14px; border: 1px solid #e2e8f0; border-radius: 8px; outline: none; transition: border-color .15s, box-shadow .15s; }
form input:focus { border-color: #4299e1; box-shadow: 0 0 0 3px rgba(66,153,225,.15); }
button[type=submit] { width: 100%; padding: 12px; margin-top: 8px; background: #2b6cb0; color: #fff; border: 0; border-radius: 8px; font-size: 15px; font-weight: 600; cursor: pointer; transition: background .15s; }
button[type=submit]:hover { background: #2c5282; }
.err { margin-top: 12px; color: #e53e3e; font-size: 13px; text-align: center; min-height: 18px; }