/* Global Styles */
:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
    --danger-color: #e74c3c;
    --warning-color: #f39c12;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

a {
    text-decoration: none;
    color: var(--primary-color);
}

a:hover {
    color: var(--dark-color);
}

ul {
    list-style: none;
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background-color: var(--dark-color);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

header h1 {
    text-align: center;
    margin-bottom: 1rem;
}

nav ul {
    display: flex;
    justify-content: center;
    gap: 20px;
}

nav a {
    color: white;
    font-weight: 500;
    padding: 5px 10px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

/* Main Content */
main {
    padding: 2rem 0;
}

section {
    margin-bottom: 2rem;
    background-color: white;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

h2, h3 {
    color: var(--dark-color);
    margin-bottom: 1rem;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

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

tr:hover {
    background-color: #f5f5f5;
}

/* Forms */
form {
    margin: 1rem 0;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

input[type="text"],
input[type="email"],
input[type="password"],
textarea,
select {
    width: 100%;
    padding: 10px;
    margin-bottom: 1rem;
    border: 1px solid #ddd;
    border-radius: 4px;
}

button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
}

button:hover {
    background-color: #2980b9;
}

/* Footer */
footer {
    text-align: center;
    padding: 1rem 0;
    background-color: var(--dark-color);
    color: white;
    margin-top: 2rem;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }

/* Responsive */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    table {
        display: block;
        overflow-x: auto;
    }
}