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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

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

/* Navbar */
.navbar {
    background-color: #2c3e50;
    color: white;
    padding: 15px 0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.navbar h1 {
    font-size: 24px;
    margin-bottom: 10px;
}

.nav-menu {
    list-style: none;
    display: flex;
    gap: 20px;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #3498db;
}

/* Cards */
.card {
    background: white;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.card h2 {
    color: #2c3e50;
    margin-bottom: 15px;
}

/* Forms */
.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: #2c3e50;
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="file"],
textarea,
select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    font-family: inherit;
}

textarea {
    min-height: 100px;
    resize: vertical;
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 5px rgba(52, 152, 219, 0.3);
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-block;
}

.btn-primary {
    background-color: #3498db;
    color: white;
}

.btn-primary:hover {
    background-color: #2980b9;
}

.btn-success {
    background-color: #27ae60;
    color: white;
}

.btn-success:hover {
    background-color: #229954;
}

.btn-danger {
    background-color: #e74c3c;
    color: white;
}

.btn-danger:hover {
    background-color: #c0392b;
}

.btn-secondary {
    background-color: #95a5a6;
    color: white;
}

.btn-secondary:hover {
    background-color: #7f8c8d;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 15px;
}

th {
    background-color: #2c3e50;
    color: white;
    padding: 12px;
    text-align: left;
}

td {
    padding: 12px;
    border-bottom: 1px solid #ddd;
}

tr:hover {
    background-color: #f9f9f9;
}

/* Alert Messages */
.alert {
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
}

.alert-success {
    background-color: #d4edda;
    border: 1px solid #c3e6cb;
    color: #155724;
}

.alert-danger {
    background-color: #f8d7da;
    border: 1px solid #f5c6cb;
    color: #721c24;
}

.alert-warning {
    background-color: #fff3cd;
    border: 1px solid #ffeaa7;
    color: #856404;
}

/* Footer */
footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px;
    margin-top: 40px;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        flex-direction: column;
        gap: 10px;
    }
    
    table {
        font-size: 12px;
    }
    
    th, td {
        padding: 8px;
    }
}