/* ===== Premium Finance Tracker UI ===== */

/* CSS Variables - Premium Color Palette */
:root {
    /* Backgrounds */
    --bg-base: #09090b;
    --bg-surface: #111113;
    --bg-elevated: #18181b;
    --bg-hover: #1f1f23;
    --bg-active: #27272a;
    
    /* Accent Colors */
    --accent-primary: #6366f1;
    --accent-primary-hover: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.15);
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a855f7 100%);
    
    /* Semantic Colors */
    --success: #10b981;
    --success-soft: rgba(16, 185, 129, 0.12);
    --danger: #ef4444;
    --danger-soft: rgba(239, 68, 68, 0.12);
    --warning: #f59e0b;
    --warning-soft: rgba(245, 158, 11, 0.12);
    --info: #3b82f6;
    --info-soft: rgba(59, 130, 246, 0.12);
    
    /* Text Colors */
    --text-primary: #fafafa;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    --text-faint: #52525b;
    
    /* Borders */
    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-default: rgba(255, 255, 255, 0.1);
    --border-strong: rgba(255, 255, 255, 0.15);
    
    /* Effects */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.15);
    
    /* Layout */
    --sidebar-width: 260px;
    --header-height: 64px;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-base);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Gradient Background Effect */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 100vh;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(99, 102, 241, 0.15), transparent),
        radial-gradient(ellipse 60% 40% at 100% 0%, rgba(139, 92, 246, 0.1), transparent);
    pointer-events: none;
    z-index: -1;
}

::selection {
    background: var(--accent-primary);
    color: white;
}

a {
    color: inherit;
    text-decoration: none;
}

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

/* ===== Mobile Header ===== */
.mobile-header {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(17, 17, 19, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-subtle);
    padding: 0 20px;
    align-items: center;
    gap: 16px;
    z-index: 100;
}

.menu-toggle {
    background: var(--bg-elevated);
    border: 1px solid var(--border-default);
    color: var(--text-primary);
    cursor: pointer;
    padding: 10px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.menu-toggle:hover {
    background: var(--bg-hover);
    border-color: var(--border-strong);
}

.mobile-logo {
    font-weight: 600;
    font-size: 18px;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ===== Sidebar ===== */
.sidebar {
    width: var(--sidebar-width);
    background: var(--bg-surface);
    border-right: 1px solid var(--border-subtle);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    z-index: 200;
    transition: transform var(--transition-slow);
}

.sidebar-header {
    padding: 24px 20px;
    border-bottom: 1px solid var(--border-subtle);
}

.logo {
    display: flex;
    align-items: center;
    gap: 14px;
}

.logo-icon {
    width: 44px;
    height: 44px;
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    box-shadow: var(--shadow-glow);
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-weight: 700;
    font-size: 17px;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.logo-subtitle {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
}

.sidebar-nav {
    flex: 1;
    padding: 20px 12px;
    overflow-y: auto;
}

.nav-section {
    margin-bottom: 28px;
}

.nav-section-title {
    display: block;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0 12px;
    margin-bottom: 10px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 11px 14px;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    transition: all var(--transition-fast);
    margin-bottom: 4px;
    position: relative;
}

.nav-item:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.nav-item.active {
    background: var(--accent-glow);
    color: var(--accent-primary-hover);
}

.nav-item.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background: var(--accent-primary);
    border-radius: 0 4px 4px 0;
}

.nav-item svg {
    flex-shrink: 0;
    opacity: 0.7;
}

.nav-item:hover svg,
.nav-item.active svg {
    opacity: 1;
}

.sidebar-footer {
    padding: 16px;
    border-top: 1px solid var(--border-subtle);
}

.user-card {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px;
    background: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    margin-bottom: 12px;
}

.user-avatar {
    width: 38px;
    height: 38px;
    background: var(--accent-gradient);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 15px;
    color: white;
}

.user-info {
    flex: 1;
    min-width: 0;
}

.user-name {
    display: block;
    font-weight: 600;
    font-size: 14px;
    color: var(--text-primary);
}

.user-email {
    display: block;
    font-size: 12px;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.logout-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    padding: 11px;
    background: transparent;
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.logout-btn:hover {
    background: var(--danger-soft);
    border-color: rgba(239, 68, 68, 0.3);
    color: var(--danger);
}

.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 150;
    opacity: 0;
    transition: opacity var(--transition-base);
}

/* ===== Main Content ===== */
.main {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

.main-content {
    padding: 40px;
    max-width: 1400px;
    margin: 0 auto;
}

/* ===== Page Header ===== */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 24px;
    margin-bottom: 36px;
    flex-wrap: wrap;
}

.page-header h1 {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.03em;
    line-height: 1.2;
}

.page-subtitle {
    color: var(--text-secondary);
    font-size: 15px;
    margin-top: 6px;
    font-weight: 400;
}

.page-subtitle strong {
    color: var(--text-primary);
    font-weight: 600;
}

.header-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 11px 20px;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.btn svg {
    width: 16px;
    height: 16px;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 2px 12px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--bg-elevated);
    border: 1px solid var(--border-default);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: var(--bg-hover);
    border-color: var(--border-strong);
}

.btn-success {
    background: var(--success);
    color: white;
    box-shadow: 0 2px 12px rgba(16, 185, 129, 0.3);
}

.btn-success:hover {
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.4);
    transform: translateY(-1px);
}

.btn-danger {
    background: var(--danger-soft);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

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

.btn-sm {
    padding: 8px 14px;
    font-size: 13px;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 15px;
}

/* ===== Stats Grid ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 36px;
}

.stat-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 24px;
    display: flex;
    align-items: flex-start;
    gap: 18px;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--card-accent, var(--accent-primary)), transparent);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.stat-card:hover {
    border-color: var(--border-default);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.stat-card:hover::before {
    opacity: 1;
}

.stat-card.income { --card-accent: var(--success); }
.stat-card.expense { --card-accent: var(--danger); }
.stat-card.balance { --card-accent: var(--accent-primary); }
.stat-card.partner1 { --card-accent: var(--info); }
.stat-card.partner2 { --card-accent: var(--warning); }

.stat-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.stat-card.income .stat-icon { background: var(--success-soft); color: var(--success); }
.stat-card.expense .stat-icon { background: var(--danger-soft); color: var(--danger); }
.stat-card.balance .stat-icon { background: var(--accent-glow); color: var(--accent-primary); }
.stat-card.partner1 .stat-icon { background: var(--info-soft); color: var(--info); }
.stat-card.partner2 .stat-icon { background: var(--warning-soft); color: var(--warning); }

.stat-info {
    flex: 1;
    min-width: 0;
}

.stat-label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 6px;
}

.stat-value {
    font-size: 28px;
    font-weight: 700;
    font-family: 'JetBrains Mono', 'SF Mono', monospace;
    color: var(--text-primary);
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.stat-sub {
    display: block;
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 8px;
    line-height: 1.5;
}

.stat-sub strong {
    color: var(--text-primary);
}

/* ===== Cards ===== */
.card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: all var(--transition-base);
}

.card:hover {
    border-color: var(--border-default);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-subtle);
    background: var(--bg-elevated);
}

.card-header h2 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.01em;
}

.card-body {
    padding: 24px;
}

.card-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border-subtle);
    background: var(--bg-elevated);
}

/* ===== Grid Layouts ===== */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

/* ===== Tables ===== */
.table-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

.data-table th {
    text-align: left;
    padding: 14px 20px;
    font-size: 12px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border-subtle);
    white-space: nowrap;
    position: sticky;
    top: 0;
}

.data-table td {
    padding: 16px 20px;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-subtle);
    vertical-align: middle;
}

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

.data-table tbody tr:hover td {
    background: var(--bg-hover);
}

.data-table tbody tr:last-child td {
    border-bottom: none;
}

.data-table .amount {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 500;
    font-size: 13px;
}

.data-table .amount.positive { color: var(--success); }
.data-table .amount.negative { color: var(--danger); }

.data-table .actions {
    display: flex;
    gap: 8px;
}

/* ===== Badges ===== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 0.01em;
}

.badge-category {
    background: var(--accent-glow);
    color: var(--accent-primary-hover);
}

.badge-person {
    background: var(--warning-soft);
    color: var(--warning);
}

.badge-both {
    background: var(--success-soft);
    color: var(--success);
}

.badge-info {
    background: var(--info-soft);
    color: var(--info);
}

/* ===== Forms ===== */
.form-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group.full-width {
    grid-column: span 2;
}

.form-group label {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 10px;
}

.form-group label .required {
    color: var(--danger);
    margin-left: 2px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 13px 16px;
    background: var(--bg-elevated);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 14px;
    font-family: inherit;
    transition: all var(--transition-fast);
}

.form-group input:hover,
.form-group select:hover,
.form-group textarea:hover {
    border-color: var(--border-strong);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
    background: var(--bg-surface);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-faint);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2371717a' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    padding-right: 44px;
}

.form-actions {
    display: flex;
    gap: 12px;
    margin-top: 32px;
    padding-top: 32px;
    border-top: 1px solid var(--border-subtle);
}

.form-hint {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 8px;
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 13px 0;
}

.checkbox-group input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--accent-primary);
}

/* ===== Alerts ===== */
.alert {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: 24px;
    font-size: 14px;
    font-weight: 500;
}

.alert-success {
    background: var(--success-soft);
    border: 1px solid rgba(16, 185, 129, 0.2);
    color: var(--success);
}

.alert-danger {
    background: var(--danger-soft);
    border: 1px solid rgba(239, 68, 68, 0.2);
    color: var(--danger);
}

.alert-warning {
    background: var(--warning-soft);
    border: 1px solid rgba(245, 158, 11, 0.2);
    color: var(--warning);
}

.alert-info {
    background: var(--info-soft);
    border: 1px solid rgba(59, 130, 246, 0.2);
    color: var(--info);
}

/* ===== Settlement Card ===== */
.settlement-card {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 24px;
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    margin-bottom: 36px;
    position: relative;
    overflow: hidden;
}

.settlement-card::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
}

.settlement-card.positive::before {
    background: var(--success);
}

.settlement-card.negative::before {
    background: var(--warning);
}

.settlement-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    background: var(--bg-elevated);
}

.settlement-info h3 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.settlement-info p {
    font-size: 14px;
    color: var(--text-secondary);
}

.settlement-amount {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 600;
    font-size: 16px;
}

/* ===== Empty State ===== */
.empty-state {
    text-align: center;
    padding: 60px 24px;
    color: var(--text-secondary);
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: 20px;
    opacity: 0.3;
    color: var(--text-muted);
}

.empty-state p {
    margin-bottom: 20px;
    font-size: 15px;
}

/* ===== Transaction List ===== */
.transaction-list {
    display: flex;
    flex-direction: column;
}

.transaction-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 24px;
    border-bottom: 1px solid var(--border-subtle);
    transition: background var(--transition-fast);
}

.transaction-item:last-child {
    border-bottom: none;
}

.transaction-item:hover {
    background: var(--bg-hover);
}

.transaction-info {
    display: flex;
    flex-direction: column;
    gap: 4px;
    min-width: 0;
}

.transaction-desc {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.transaction-meta {
    font-size: 13px;
    color: var(--text-muted);
}

.transaction-amount {
    font-family: 'JetBrains Mono', monospace;
    font-size: 14px;
    font-weight: 600;
    white-space: nowrap;
}

.transaction-amount.positive { color: var(--success); }
.transaction-amount.negative { color: var(--danger); }

/* ===== Reports ===== */
.report-filters {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    align-items: flex-end;
}

.filter-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.filter-group label {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-muted);
}

.filter-group select,
.filter-group input {
    padding: 10px 14px;
    background: var(--bg-elevated);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 14px;
}

.export-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.report-section {
    margin-bottom: 36px;
}

.report-section h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-subtle);
    letter-spacing: -0.01em;
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
}

.summary-item {
    padding: 20px;
    background: var(--bg-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.summary-item:hover {
    border-color: var(--border-default);
}

.summary-item .label {
    display: block;
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.summary-item .value {
    font-size: 22px;
    font-weight: 600;
    font-family: 'JetBrains Mono', monospace;
    letter-spacing: -0.01em;
}

/* ===== Login Page ===== */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: var(--bg-base);
    position: relative;
}

.login-page::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse 80% 60% at 50% 0%, rgba(99, 102, 241, 0.2), transparent),
        radial-gradient(ellipse 50% 40% at 80% 50%, rgba(139, 92, 246, 0.15), transparent),
        radial-gradient(ellipse 50% 40% at 20% 80%, rgba(99, 102, 241, 0.1), transparent);
    pointer-events: none;
}

.login-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    padding: 48px 40px;
    box-shadow: var(--shadow-lg);
    position: relative;
    z-index: 1;
}

.login-logo {
    text-align: center;
    margin-bottom: 40px;
}

.login-logo .logo-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    border-radius: var(--radius-lg);
}

.login-logo h1 {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.02em;
}

.login-logo p {
    font-size: 15px;
    color: var(--text-secondary);
}

.login-form .form-group {
    margin-bottom: 24px;
}

.login-form .btn {
    width: 100%;
    margin-top: 8px;
    padding: 14px;
}

.login-footer {
    text-align: center;
    margin-top: 32px;
    font-size: 13px;
    color: var(--text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .sidebar-overlay.open {
        display: block;
        opacity: 1;
    }
    
    .mobile-header {
        display: flex;
    }
    
    .main {
        margin-left: 0;
    }
    
    .main-content {
        padding: calc(var(--header-height) + 24px) 24px 24px;
    }
    
    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .page-header {
        flex-direction: column;
        align-items: stretch;
        gap: 20px;
    }
    
    .page-header h1 {
        font-size: 26px;
    }
    
    .header-actions {
        width: 100%;
    }
    
    .header-actions .btn {
        flex: 1;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .form-group.full-width {
        grid-column: span 1;
    }
    
    .data-table th,
    .data-table td {
        padding: 14px 16px;
    }
    
    .stat-card {
        padding: 20px;
    }
    
    .stat-value {
        font-size: 24px;
    }
    
    .settlement-card {
        flex-direction: column;
        text-align: center;
    }
    
    .report-filters {
        flex-direction: column;
    }
    
    .filter-group {
        width: 100%;
    }
    
    .export-buttons {
        flex-direction: column;
    }
    
    .export-buttons .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: calc(var(--header-height) + 16px) 16px 16px;
    }
    
    .page-header h1 {
        font-size: 22px;
    }
    
    .login-card {
        padding: 36px 28px;
    }
    
    .card-body {
        padding: 20px;
    }
    
    .transaction-item {
        padding: 16px 20px;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .form-actions .btn {
        width: 100%;
    }
}

/* ===== Print Styles ===== */
@media print {
    .sidebar,
    .mobile-header,
    .header-actions,
    .btn,
    .actions {
        display: none !important;
    }
    
    .main {
        margin-left: 0 !important;
    }
    
    .main-content {
        padding: 20px !important;
    }
    
    body {
        background: white;
        color: #1a1a1a;
    }
    
    body::before {
        display: none;
    }
    
    .card,
    .stat-card {
        border: 1px solid #ddd;
        box-shadow: none;
        background: white;
    }
    
    .stat-value,
    .data-table .amount {
        color: #1a1a1a !important;
    }
}

/* ===== Utilities ===== */
.text-success { color: var(--success) !important; }
.text-danger { color: var(--danger) !important; }
.text-warning { color: var(--warning) !important; }
.text-muted { color: var(--text-muted) !important; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.font-mono { font-family: 'JetBrains Mono', monospace; }
.font-bold { font-weight: 600; }
.mt-4 { margin-top: 16px; }
.mb-4 { margin-bottom: 16px; }
.mb-6 { margin-bottom: 24px; }
.hidden { display: none; }

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

::-webkit-scrollbar-track {
    background: transparent;
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--border-strong);
}

/* ===== Focus Visible ===== */
:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

/* ===== Animations ===== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.card,
.stat-card,
.settlement-card {
    animation: fadeIn 0.4s ease-out;
}

.stats-grid .stat-card:nth-child(1) { animation-delay: 0ms; }
.stats-grid .stat-card:nth-child(2) { animation-delay: 50ms; }
.stats-grid .stat-card:nth-child(3) { animation-delay: 100ms; }
.stats-grid .stat-card:nth-child(4) { animation-delay: 150ms; }
.stats-grid .stat-card:nth-child(5) { animation-delay: 200ms; }