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

:root {
    --primary-color: #667eea;
    --primary-dark: #5568d3;
    --secondary-color: #764ba2;
    --danger-color: #e74c3c;
    --danger-hover: #c0392b;
    --success-color: #27ae60;
    --text-dark: #2c3e50;
    --text-light: #7f8c8d;
    --border-color: #e1e8ed;
    --background: #f5f8fa;
    --card-background: #ffffff;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif;
    background: var(--background);
    color: var(--text-dark);
    line-height: 1.6;
}

/* Navbar */
.navbar {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: var(--shadow);
}

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

.navbar-brand h1 {
    font-size: 1.5rem;
    font-weight: 600;
}

.navbar-menu {
    display: flex;
    gap: 1rem;
}

.navbar-item {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    transition: background 0.3s ease;
}

.navbar-item:hover,
.navbar-item.active {
    background: rgba(255, 255, 255, 0.2);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.main-content {
    padding: 2rem 1rem;
}

/* Login */
.login-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.login-box {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow-hover);
    width: 100%;
    max-width: 400px;
}

.login-box h1 {
    text-align: center;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.login-box h2 {
    text-align: center;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
    font-size: 1.2rem;
    font-weight: 400;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--card-background);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.stat-icon {
    font-size: 2.5rem;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* Card */
.card {
    background: var(--card-background);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

.card h2 {
    margin-bottom: 1rem;
    color: var(--text-dark);
    font-size: 1.3rem;
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
    font-weight: 500;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: 1rem;
    align-items: end;
}

.flex-grow {
    flex-grow: 1;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: var(--text-light);
    color: white;
}

.btn-secondary:hover {
    background: var(--text-dark);
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background: var(--danger-hover);
}

.btn-small {
    padding: 0.4rem 0.8rem;
    font-size: 0.9rem;
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: 5px;
    margin-bottom: 1rem;
}

.alert-error {
    background: #fadbd8;
    color: #c0392b;
    border: 1px solid #e74c3c;
}

.alert-success {
    background: #d5f4e6;
    color: #186a3b;
    border: 1px solid #27ae60;
}

.result-message {
    margin-top: 1rem;
}

/* Search Form */
.search-form {
    display: flex;
    gap: 0.5rem;
}

.search-form input {
    flex: 1;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 1rem;
}

/* Table */
.table-responsive {
    overflow-x: auto;
}

.urls-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.urls-table th,
.urls-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.urls-table th {
    background: var(--background);
    font-weight: 600;
    color: var(--text-dark);
}

.urls-table tr:hover {
    background: var(--background);
}

.urls-table .short-link {
    color: var(--primary-color);
    font-weight: 600;
    text-decoration: none;
}

.urls-table .short-link:hover {
    text-decoration: underline;
}

.urls-table .long-url a {
    color: var(--text-dark);
    text-decoration: none;
}

.urls-table .long-url a:hover {
    color: var(--primary-color);
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    margin-top: 2rem;
}

.pagination-info {
    color: var(--text-light);
}

/* Popular List */
.popular-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.popular-item {
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 1rem;
    align-items: center;
    padding: 1rem;
    background: var(--background);
    border-radius: 5px;
}

.popular-code a {
    color: var(--primary-color);
    font-weight: 600;
    text-decoration: none;
}

.popular-code a:hover {
    text-decoration: underline;
}

.popular-url {
    color: var(--text-light);
    font-size: 0.9rem;
}

.popular-clicks {
    color: var(--text-dark);
    font-weight: 600;
}

/* Responsive */
@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .popular-item {
        grid-template-columns: 1fr;
    }
    
    .urls-table {
        font-size: 0.9rem;
    }
    
    .urls-table th,
    .urls-table td {
        padding: 0.5rem;
    }
}