* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #1f2937, #111827);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.login-container {
    width: 100%;
    max-width: 420px;
}

.login-card {
    background: #ffffff;
    border-radius: 18px;
    padding: 35px 30px;
    box-shadow: 0 20px 45px rgba(0, 0, 0, 0.25);
}

.login-card h1 {
    text-align: center;
    font-size: 30px;
    color: #111827;
    margin-bottom: 8px;
}

.subtitle {
    text-align: center;
    color: #6b7280;
    margin-bottom: 30px;
    font-size: 15px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #374151;
    font-weight: bold;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 14px 15px;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    font-size: 15px;
    outline: none;
    transition: 0.2s;
    background: #f9fafb;
}

.form-group input:focus {
    border-color: #2563eb;
    background: #ffffff;
    box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.12);
}

.btn-login {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 10px;
    background: #2563eb;
    color: white;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: 0.2s;
    margin-top: 10px;
}

.btn-login:hover {
    background: #1d4ed8;
}

.alert-error {
    background: #fee2e2;
    color: #b91c1c;
    border: 1px solid #fecaca;
    padding: 12px 14px;
    border-radius: 10px;
    margin-bottom: 20px;
    font-size: 14px;
    text-align: center;
}