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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header */
header {
    background-color: #343a40;
    color: #fff;
    padding: 1rem 0;
    margin-bottom: 2rem;
}

header h1 {
    margin-bottom: 1rem;
}

nav ul {
    display: flex;
    list-style: none;
    flex-wrap: wrap;
}

nav li {
    margin-right: 1.5rem;
}

nav a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

nav a:hover {
    color: #17a2b8;
}

/* Main Content */
main {
    min-height: calc(100vh - 200px);
    padding-bottom: 2rem;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

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

input[type="text"],
input[type="password"],
input[type="email"],
input[type="file"],
select,
textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input[type="text"]:focus,
input[type="password"]:focus,
input[type="email"]:focus,
select:focus,
textarea:focus {
    border-color: #17a2b8;
    outline: none;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: #17a2b8;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #138496;
}

.btn-danger {
    background-color: #dc3545;
}

.btn-danger:hover {
    background-color: #c82333;
}

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

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

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 2rem;
    background-color: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

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

th {
    background-color: #f1f1f1;
    font-weight: 600;
}

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

/* Filter Row */
.filter-row input, 
.filter-row select {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 0.9rem;
}

/* Categories */
.category-header {
    background-color: #343a40;
    color: #fff;
    padding: 0.75rem 1rem;
    font-weight: 600;
    font-size: 1.1rem;
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
    border-radius: 4px;
}

/* Flash Messages */
.alert {
    padding: 1rem;
    margin-bottom: 1.5rem;
    border-radius: 4px;
    font-weight: 500;
}

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

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

.info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* Tags Input for Subcategories */
.tags-input {
    display: flex;
    flex-wrap: wrap;
    border: 1px solid #ddd;
    border-radius: 4px;
    padding: 0.5rem;
    background-color: #fff;
}

.tags-input .tag {
    display: inline-block;
    background-color: #17a2b8;
    color: white;
    padding: 0.3rem 0.6rem;
    margin: 0.3rem;
    border-radius: 3px;
    font-size: 0.9rem;
}

.tags-input .tag .close {
    margin-left: 0.5rem;
    cursor: pointer;
}

.tags-input input {
    flex: 1;
    border: none;
    outline: none;
    padding: 0.5rem;
    font-size: 1rem;
}

/* Footer */
footer {
    background-color: #343a40;
    color: #fff;
    text-align: center;
    padding: 1.5rem 0;
    margin-top: 2rem;
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
    }
    
    nav li {
        margin-right: 0;
        margin-bottom: 0.5rem;
    }
    
    table {
        display: block;
        overflow-x: auto;
    }
}