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

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

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

/* Navbar */
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar-brand {
    color: white;
    text-decoration: none;
    font-size: 1.5em;
    font-weight: bold;
}

.navbar-menu {
    display: flex;
    gap: 20px;
}

.navbar-menu a {
    color: white;
    text-decoration: none;
    padding: 8px 15px;
    border-radius: 5px;
    transition: background 0.3s;
}

.navbar-menu a:hover {
    background: rgba(255,255,255,0.2);
}

.btn-back-admin {
    background: #ffc107 !important;
    color: #333 !important;
    font-weight: bold;
    padding: 8px 15px;
    border-radius: 5px;
}

.btn-back-admin:hover {
    background: #ffca28 !important;
}

/* Main content */
main {
    min-height: calc(100vh - 200px);
    padding: 40px 0;
}

/* Footer */
footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 20px 0;
    margin-top: 40px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 10px 25px;
    border-radius: 5px;
    text-decoration: none;
    border: none;
    cursor: pointer;
    font-size: 1em;
    transition: all 0.3s;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5568d3;
}

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

.btn-success {
    background: #28a745;
    color: white;
}

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

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

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1em;
}

.form-control:focus {
    outline: none;
    border-color: #667eea;
}

/* Alerts */
.alert {
    padding: 15px;
    margin-bottom: 20px;
    border-radius: 5px;
}

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

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

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

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

.card-title {
    font-size: 1.5em;
    margin-bottom: 15px;
    color: #667eea;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
}

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

table th {
    background: #f8f9fa;
    font-weight: 600;
}

table tr:hover {
    background: #f8f9fa;
}