body {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}
.login-container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
    padding: 2rem;
    backdrop-filter: blur(10px);
    animation: fadeIn 0.5s ease-in-out;
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}
.login-header {
    text-align: center;
    margin-bottom: 2rem;
    color: #2d3748;
}
.login-header h1 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}
.login-header p {
    color: #718096;
    font-size: 0.95rem;
}
.form-group label {
    font-weight: 500;
    color: #4a5568;
    margin-bottom: 0.5rem;
}
.form-control {
    border: 2px solid #e2e8f0;
    border-radius: 10px;
    padding: 0.75rem 1rem;
    transition: all 0.3s ease;
}
.form-control:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}
.input-group-text {
    background: transparent;
    border: 2px solid #e2e8f0;
    border-right: none;
    color: #718096;
}
.input-group .form-control {
    border-left: none;
}
.btn-login {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 10px;
    padding: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
}
.btn-login:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}
.alert {
    border-radius: 10px;
    padding: 1rem;
    margin-bottom: 1.5rem;
}
.system-icon {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}