:root {
    --green: #2ecc71;
    --dark-green: #27ae60;
    --yellow: #f1c40f;
    --black: #2c3e50;
    --white: #ffffff;
}

body {
    font-family: 'Arial', sans-serif;
    background: #f9f9f9;
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

.container {
    max-width: 650px;
    margin: 30px auto;
    padding: 20px;
}

header {
    background: var(--green);
    padding: 20px;
    border-radius: 5px;
    text-align: center;
    margin-bottom: 30px;
    color: var(--white);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    position: relative;
}

header h1 {
    margin: 0;
    font-size: 2.5em;
}

.onza { color: var(--white); }
.sms { color: var(--yellow); font-weight: bold; }

.login-form, .message-form {
    background: var(--white);
    padding: 30px;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.error {
    color: #ff3333;
    text-align: center;
    margin-bottom: 15px;
    padding: 10px;
    background: #ffeeee;
    border-radius: 4px;
}

.user-controls {
    position: absolute;
    top: 20px;
    right: 20px;
}

.logout-btn {
    color: var(--yellow);
    text-decoration: none;
    font-weight: bold;
    padding: 5px 10px;
    border-radius: 3px;
    background: rgba(0,0,0,0.2);
}

.logout-btn:hover {
    background: rgba(0,0,0,0.3);
}

/* Form styles continue as before... */