/* General Styles */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f0f0;
    color: #333;
}

/* Header */
header {
    background-color: #007bff;
    color: white;
    padding: 15px 20px;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

header h1 {
    margin: 0;
    font-size: 24px;
    letter-spacing: 1px;
}

nav {
    margin-top: 10px;
    display: flex;
    justify-content: center;
    gap: 10px;
}

nav button {
    background-color: #0069d9;
    color: white;
    border: none;
    padding: 10px 15px;
    font-size: 16px;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

nav button:hover {
    background-color: #0056b3;
}

/* Main Content */
main {
    padding: 20px;
    max-width: 1200px;
    margin: 0 auto;
}

/* Chart Container */
#charts-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.chart-section {
    background-color: white;
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.chart-container {
    width: 100%;
    height: 400px;
    box-sizing: border-box;
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    header h1 {
        font-size: 20px;
    }

    nav button {
        font-size: 14px;
        padding: 8px 12px;
    }

    .chart-section h2 {
        font-size: 16px;
    }

    .chart-container {
        height: 300px;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 18px;
    }

    nav {
        flex-direction: column;
        gap: 5px;
    }

    nav button {
        width: 100%;
        padding: 10px;
    }

    .chart-section h2 {
        font-size: 14px;
    }

    .chart-container {
        height: 250px;
    }
}

/* Form Styles */
.add-purchase {
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
}

input[type="text"], input[type="number"], input[type="password"], select {
    width: 100%;
    padding: 10px;
    margin: 10px 0;
    border-radius: 4px;
    border: 1px solid #ccc;
    box-sizing: border-box;
}

button[type="submit"] {
    background-color: #28a745;
    color: white;
    border: none;
    padding: 10px;
    font-size: 16px;
    border-radius: 4px;
    width: 100%;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button[type="submit"]:hover {
    background-color: #218838;
}

/* Links */
a {
    color: #007bff;
    text-decoration: none;
    display: inline-block;
    margin-top: 10px;
}

a:hover {
    text-decoration: underline;
}

/* Login and Register Styles */
.login-container, .register-container {
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    margin: 0 auto;
}

.login-container h2, .register-container h2 {
    font-size: 24px;
    margin-bottom: 20px;
}

.login-container form, .register-container form {
    display: flex;
    flex-direction: column;
}

.login-container input, .register-container input {
    margin: 10px 0;
}

.login-container button, .register-container button {
    margin-top: 10px;
}