:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #ec4899;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #06b6d4;
    --dark: #1f2937;
    --light: #f9fafb;
    --sidebar-width: 280px;
    --header-height: 80px;
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

[data-theme="dark"] {
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
    --bg-tertiary: #374151;
    --text-primary: #f9fafb;
    --text-secondary: #e5e7eb;
    --text-muted: #9ca3af;
    --border-color: #374151;
    --card-bg: rgba(31, 41, 55, 0.7);
    --glass-effect: rgba(31, 41, 55, 0.5);
    --glass-border: rgba(255, 255, 255, 0.1);
}

[data-theme="light"] {
    --bg-primary: #f9fafb;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f3f4f6;
    --text-primary: #111827;
    --text-secondary: #374151;
    --text-muted: #6b7280;
    --border-color: #e5e7eb;
    --card-bg: rgba(255, 255, 255, 0.7);
    --glass-effect: rgba(255, 255, 255, 0.5);
    --glass-border: rgba(0, 0, 0, 0.1);
}

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

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    transition: var(--transition);
    min-height: 100vh;
}

/* Layout */
.app-container {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: var(--sidebar-width);
    background: var(--bg-secondary);
    color: var(--text-primary);
    position: fixed;
    height: 100vh;
    padding: 20px 0;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    overflow-y: auto;
    transition: var(--transition);
    border-right: 1px solid var(--border-color);
}

.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    padding: 30px;
    transition: var(--transition);
    background: var(--bg-primary);
}

/* Header */
.header {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 20px 30px;
    border-radius: var(--border-radius);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 1px solid var(--glass-border);
}

.header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Cards */
.card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--border-radius);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
    margin-bottom: 25px;
    transition: var(--transition);
    overflow: hidden;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
}

.card-header {
    background: transparent;
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    padding: 20px;
    color: var(--text-primary);
}

.card-body {
    padding: 25px;
}

/* Buttons */
.btn {
    border-radius: 8px;
    padding: 10px 20px;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(99, 102, 241, 0.3);
}

.btn-success {
    background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
    color: white;
}

.btn-danger {
    background: linear-gradient(135deg, var(--danger) 0%, #dc2626 100%);
    color: white;
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-outline-primary {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

.btn-outline-primary:hover {
    background: var(--primary);
    color: white;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.875rem;
}

/* Tables */
.table {
    border-collapse: separate;
    border-spacing: 0;
    width: 100%;
    color: var(--text-primary);
}

.table th {
    background-color: var(--bg-tertiary);
    border-top: 1px solid var(--border-color);
    font-weight: 600;
    padding: 15px;
    text-align: left;
}

.table td {
    padding: 15px;
    vertical-align: middle;
    border-bottom: 1px solid var(--border-color);
}

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

.table tr:hover {
    background-color: var(--bg-tertiary);
}

/* Navigation */
.nav-item {
    margin-bottom: 5px;
}

.nav-link {
    color: var(--text-secondary);
    border-radius: 8px;
    padding: 12px 20px;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 12px;
}

.nav-link:hover, .nav-link.active {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    transform: translateX(5px);
}

.nav-link i {
    width: 20px;
    text-align: center;
}

/* Forms */
.form-control {
    border-radius: 8px;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.form-label {
    color: var(--text-primary);
    font-weight: 500;
    margin-bottom: 8px;
}

.form-select {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.form-select:focus {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.input-group-text {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

/* Dashboard Stats */
.stats-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, var(--card-bg) 0%, var(--glass-effect) 100%);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--border-radius);
    padding: 25px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 20px;
    font-size: 1.8rem;
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
}

.income .stat-icon {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.expense .stat-icon {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

.balance .stat-icon {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
}

.stat-info h4 {
    margin: 0;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
}

.stat-info p {
    margin: 0;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Badges */
.badge {
    border-radius: 20px;
    padding: 6px 12px;
    font-weight: 600;
}

.bg-success {
    background: linear-gradient(135deg, var(--success) 0%, #059669 100%) !important;
}

.bg-danger {
    background: linear-gradient(135deg, var(--danger) 0%, #dc2626 100%) !important;
}

.bg-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%) !important;
}

/* Alerts */
.alert {
    border-radius: var(--border-radius);
    padding: 15px 20px;
    border: none;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border-left: 4px solid var(--success);
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
    border-left: 4px solid var(--danger);
}

/* Theme Toggle */
.theme-toggle {
    background: var(--bg-tertiary);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-primary);
}

.theme-toggle:hover {
    background: var(--primary);
    color: white;
    transform: rotate(30deg);
}

/* Login & Register Pages */
.auth-container {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 450px;
    overflow: hidden;
    border: 1px solid var(--glass-border);
}

.auth-header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

.auth-header i {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.auth-header h1 {
    font-size: 2rem;
    margin: 0;
    font-weight: 700;
}

.auth-body {
    padding: 30px;
}

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

.fade-in {
    animation: fadeIn 0.6s ease forwards;
}

@keyframes slideIn {
    from { transform: translateX(-20px); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

.slide-in {
    animation: slideIn 0.5s ease forwards;
}

/* Chart Containers */
.chart-container {
    position: relative;
    height: 350px;
    width: 100%;
}

/* Responsive */
@media (max-width: 1200px) {
    .sidebar {
        width: 80px;
        overflow: visible;
    }
    
    .sidebar .nav-link span {
        display: none;
    }
    
    .sidebar .nav-link i {
        margin-right: 0;
        font-size: 1.3rem;
    }
    
    .main-content {
        margin-left: 80px;
        padding: 20px;
    }
    
    .brand-text {
        display: none;
    }
    
    .stats-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .sidebar {
        display: none;
        width: 0;
    }
    
    .main-content {
        margin-left: 0;
        padding: 15px;
    }
    
    .header {
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }
    
    .header > div {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 10px;
    }
    
    .stats-container {
        grid-template-columns: 1fr;
    }
    
    .table-responsive {
        overflow-x: auto;
    }
    
    .auth-container {
        margin: 20px;
        width: auto;
    }
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 1100;
    background: var(--primary);
    color: white;
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

@media (max-width: 768px) {
    .mobile-menu-btn {
        display: flex;
    }
    
    .sidebar.show {
        display: block;
        width: 280px;
        z-index: 1000;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}