/* ===================================
   MODERN UI - CORE STYLES
   Professional PHP-like SaaS Design
   =================================== */

/* CSS Variables for Easy Theming */
:root {
    /* Primary Colors */
    --primary-color: #5bc0be;
    --primary-dark: #3a9d9b;
    --primary-light: #7dd4d2;
    
    /* Secondary Colors */
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    
    /* Neutral Colors */
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-primary: #2c3e50;
    --text-secondary: #6c757d;
    --text-muted: #95a5a6;
    --border-color: #e9ecef;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.15);
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 15px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

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

.navbar-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: white !important;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.navbar-brand i {
    font-size: 1.75rem;
}

.navbar-nav .nav-link {
    color: rgba(255, 255, 255, 0.9) !important;
    font-weight: 500;
    padding: 0.5rem 1rem !important;
    margin: 0 0.25rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.navbar-nav .nav-link:hover {
    background-color: rgba(255, 255, 255, 0.15);
    color: white !important;
    transform: translateY(-1px);
}

.navbar-nav .nav-link.active {
    background-color: rgba(255, 255, 255, 0.2);
    color: white !important;
}

/* Container */
.main-container {
    padding: 2rem 0;
    min-height: calc(100vh - 200px);
}

/* Cards */
.card {
    background: var(--surface-color);
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    overflow: hidden;
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.card-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    font-weight: 600;
    padding: 1.25rem 1.5rem;
    border: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.card-header i {
    margin-right: 0.5rem;
}

.card-body {
    padding: 1.5rem;
}

/* Buttons */
.btn {
    font-weight: 500;
    padding: 0.625rem 1.5rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

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

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-color) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-success {
    background: linear-gradient(135deg, #28a745 0%, #218838 100%);
    color: white;
}

.btn-danger {
    background: linear-gradient(135deg, #dc3545 0%, #c82333 100%);
    color: white;
}

.btn-warning {
    background: linear-gradient(135deg, #ffc107 0%, #e0a800 100%);
    color: #212529;
}

.btn-info {
    background: linear-gradient(135deg, #17a2b8 0%, #138496 100%);
    color: white;
}

.btn-info:hover {
    background: linear-gradient(135deg, #138496 0%, #17a2b8 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: linear-gradient(135deg, #6c757d 0%, #5a6268 100%);
    color: white;
}

.btn-secondary:hover {
    background: linear-gradient(135deg, #5a6268 0%, #6c757d 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-sm {
    padding: 0.375rem 1rem;
    font-size: 0.875rem;
}

.btn-lg {
    padding: 0.875rem 2rem;
    font-size: 1.125rem;
}

/* Balance Actions Container */
.balance-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

.balance-actions .btn {
    flex: 1;
    min-width: 180px;
    text-align: center;
    justify-content: center;
}

/* Forms */
.form-control, .form-select {
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    font-size: 0.9375rem;
    transition: all var(--transition-fast);
}

.form-control:focus, .form-select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(91, 192, 190, 0.1);
    outline: none;
}

.form-label {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    display: block;
}

.input-group {
    box-shadow: var(--shadow-sm);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.input-group-text {
    background-color: var(--bg-color);
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    font-weight: 500;
}

/* Tables */
.table {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.table thead th {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.8125rem;
    letter-spacing: 0.5px;
    padding: 1rem;
    border: none;
}

.table tbody tr {
    transition: all var(--transition-fast);
}

.table tbody tr:hover {
    background-color: rgba(91, 192, 190, 0.05);
    transform: scale(1.01);
}

.table tbody td {
    padding: 1rem;
    vertical-align: middle;
    border-bottom: 1px solid var(--border-color);
}

/* Alerts */
.alert {
    border: none;
    border-radius: var(--radius-lg);
    padding: 1.25rem 1.5rem;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid;
}

.alert-success {
    background-color: #d4edda;
    border-left-color: #28a745;
    color: #155724;
}

.alert-danger {
    background-color: #f8d7da;
    border-left-color: #dc3545;
    color: #721c24;
}

.alert-warning {
    background-color: #fff3cd;
    border-left-color: #ffc107;
    color: #856404;
}

.alert-info {
    background-color: #d1ecf1;
    border-left-color: #17a2b8;
    color: #0c5460;
}

/* Badges */
.badge {
    padding: 0.5rem 0.875rem;
    border-radius: var(--radius-lg);
    font-weight: 600;
    font-size: 0.8125rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Footer */
footer {
    background: linear-gradient(135deg, var(--text-primary) 0%, #1a252f 100%);
    color: rgba(255, 255, 255, 0.8);
    padding: 2rem 0;
    margin-top: 3rem;
}

footer p {
    margin: 0;
}

/* Utility Classes */
.text-gradient {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.5s ease-out;
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-container {
        padding: 1rem 0;
    }
    
    .card-body {
        padding: 1rem;
    }
    
    .table {
        font-size: 0.875rem;
    }
    
    .table thead th,
    .table tbody td {
        padding: 0.75rem 0.5rem;
    }
}

@media (max-width: 576px) {
    h1 { font-size: 1.5rem; }
    h2 { font-size: 1.25rem; }
    h3 { font-size: 1.125rem; }
    
    .btn {
        padding: 0.5rem 1rem;
        font-size: 0.875rem;
    }
}