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

:root {
    --primary-color: #0066cc;
    --secondary-color: #004499;
    --text-color: #333;
    --bg-color: #f5f5f5;
    --card-bg: #ffffff;
    --border-color: #e0e0e0;
    --success-color: #28a745;
    --error-color: #dc3545;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 700px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px 0;
}

.logo {
    max-width: 180px;
    height: auto;
    margin-bottom: 15px;
}

h1 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.subtitle {
    color: #666;
    font-size: 1rem;
}

main {
    flex: 1;
}

.settings-section {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
}

.settings-section h2 {
    font-size: 1.5rem;
    margin-bottom: 25px;
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.two-column {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 15px;
}

.two-column > div {
    display: flex;
    flex-direction: column;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-color);
}

.tooltip {
    cursor: help;
    margin-left: 5px;
    font-size: 0.9rem;
    opacity: 0.6;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-actions {
    display: flex;
    gap: 15px;
    margin-top: 30px;
    justify-content: center;
}

.btn {
    padding: 12px 30px;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--secondary-color);
}

.btn-secondary {
    background-color: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background-color: #5a6268;
}

.message {
    margin-top: 20px;
    padding: 15px;
    border-radius: 8px;
    text-align: center;
}

.message.success {
    background-color: #d4edda;
    border: 1px solid var(--success-color);
    color: #155724;
}

.message.error {
    background-color: #fee;
    border: 1px solid var(--error-color);
    color: var(--error-color);
}

footer {
    text-align: center;
    padding: 30px 0;
    margin-top: 40px;
    border-top: 1px solid var(--border-color);
}

.back-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.back-link:hover {
    text-decoration: underline;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }

    h1 {
        font-size: 1.5rem;
    }

    .logo {
        max-width: 150px;
    }

    .settings-section {
        padding: 20px;
    }

    .two-column {
        grid-template-columns: 1fr;
    }

    .settings-section h2 {
        font-size: 1.3rem;
    }

    .form-actions {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}