/* ===== CSS Variables ===== */
:root {
    --primary: #FF6B35;
    --primary-light: #FF8F65;
    --primary-dark: #E55A2B;
    --secondary: #4A90D9;
    --success: #10B981;
    --danger: #EF4444;
    --warning: #F59E0B;
    
    --bg-primary: #F8F9FA;
    --bg-secondary: #FFFFFF;
    --bg-card: #FFFFFF;
    --bg-sidebar: #FFFFFF;
    --bg-hover: #F1F3F4;
    
    --text-primary: #1F2937;
    --text-secondary: #6B7280;
    --text-muted: #9CA3AF;
    --border-color: #E5E7EB;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-lg: 0 4px 16px rgba(0,0,0,0.12);
    
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    
    --transition: all 0.3s ease;
}

[data-theme="dark"] {
    --bg-primary: #111827;
    --bg-secondary: #1F2937;
    --bg-card: #1F2937;
    --bg-sidebar: #1F2937;
    --bg-hover: #374151;
    
    --text-primary: #F9FAFB;
    --text-secondary: #D1D5DB;
    --text-muted: #9CA3AF;
    --border-color: #374151;
    --shadow: 0 2px 8px rgba(0,0,0,0.3);
    --shadow-lg: 0 4px 16px rgba(0,0,0,0.4);
}

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

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background 0.3s ease, color 0.3s ease;
    overflow: hidden;
}

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

/* ===== Sidebar ===== */
.sidebar {
    width: 240px;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transition: var(--transition);
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    font-size: 28px;
}

.logo h1 {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 1px;
}

.sidebar-nav {
    flex: 1;
    padding: 16px 12px;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
}

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

.nav-item.active {
    background: var(--primary);
    color: white;
    box-shadow: 0 2px 8px rgba(255, 107, 53, 0.4);
}

.nav-icon {
    font-size: 18px;
    width: 24px;
    text-align: center;
}

.nav-text {
    font-size: 15px;
    font-weight: 500;
}

.sidebar-footer {
    padding: 16px 12px;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.top-bar {
    height: 60px;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    flex-shrink: 0;
}

.top-bar-left {
    display: flex;
    align-items: center;
    gap: 16px;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 20px;
    color: var(--text-primary);
    cursor: pointer;
    padding: 4px 8px;
}

.page-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
}

.theme-toggle {
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 8px 12px;
    cursor: pointer;
    font-size: 16px;
    transition: var(--transition);
}

.theme-toggle:hover {
    background: var(--primary);
    border-color: var(--primary);
}

.storage-toggle {
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 8px 12px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: var(--transition);
    margin-right: 8px;
    white-space: nowrap;
}

.storage-toggle:hover {
    background: var(--secondary);
    border-color: var(--secondary);
    color: white;
}

.storage-toggle:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* ===== Pages ===== */
.page {
    display: none;
    flex: 1;
    overflow-y: auto;
    padding: 24px;
}

.page.active {
    display: block;
}

/* ===== Summary Cards ===== */
.summary-cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 24px;
}

.summary-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 24px;
    display: flex;
    align-items: center;
    gap: 16px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

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

.card-icon {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
}

.summary-card.income .card-icon {
    background: rgba(16, 185, 129, 0.15);
}

.summary-card.expense .card-icon {
    background: rgba(239, 68, 68, 0.15);
}

.summary-card.balance .card-icon {
    background: rgba(74, 144, 217, 0.15);
}

.card-info {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.card-label {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 500;
}

.card-value {
    font-size: 22px;
    font-weight: 700;
}

.summary-card.income .card-value {
    color: var(--success);
}

.summary-card.expense .card-value {
    color: var(--danger);
}

.summary-card.balance .card-value {
    color: var(--secondary);
}

/* ===== Time Range Tabs ===== */
.time-range-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
    background: var(--bg-card);
    padding: 6px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    width: fit-content;
}

.tab-btn {
    padding: 8px 20px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
}

.tab-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.tab-btn.active {
    background: var(--primary);
    color: white;
    box-shadow: 0 2px 6px rgba(255, 107, 53, 0.3);
}

/* ===== Charts ===== */
.charts-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 24px;
}

.chart-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.chart-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.chart-container {
    position: relative;
    height: 280px;
}

/* ===== Category List ===== */
.detail-section {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.section-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.category-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.category-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

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

.category-icon {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    flex-shrink: 0;
}

.category-info {
    flex: 1;
}

.category-name {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.category-bar {
    height: 6px;
    background: var(--bg-hover);
    border-radius: 3px;
    margin-top: 6px;
    overflow: hidden;
}

.category-bar-fill {
    height: 100%;
    border-radius: 3px;
    transition: width 0.5s ease;
}

.category-amount {
    font-size: 14px;
    font-weight: 600;
    text-align: right;
    min-width: 80px;
}

/* ===== Form Styles ===== */
.record-form-container {
    max-width: 500px;
    margin: 0 auto;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.form-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
}

.form-tab {
    flex: 1;
    padding: 12px;
    border: 2px solid var(--border-color);
    background: transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: var(--transition);
}

.form-tab:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.form-tab.active {
    border-color: var(--primary);
    background: var(--primary);
    color: white;
}

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

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.form-input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 15px;
    transition: var(--transition);
}

.form-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.15);
}

.amount-input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.currency-symbol {
    position: absolute;
    left: 16px;
    font-size: 16px;
    color: var(--text-muted);
    font-weight: 600;
}

.amount-input {
    padding-left: 36px !important;
    font-size: 20px !important;
    font-weight: 600;
}

.category-select {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
}

.category-option {
    padding: 12px 8px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    cursor: pointer;
    text-align: center;
    transition: var(--transition);
    font-size: 13px;
}

.category-option:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.category-option.selected {
    border-color: var(--primary);
    background: var(--primary);
    color: white;
}

.category-option .cat-icon {
    display: block;
    font-size: 20px;
    margin-bottom: 4px;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 12px 20px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(255, 107, 53, 0.4);
}

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

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

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

.btn-danger:hover {
    background: #DC2626;
}

.btn-sm {
    padding: 8px 12px;
    font-size: 13px;
}

.btn-block {
    width: 100%;
    padding: 14px;
    font-size: 16px;
}

/* ===== Detail Page ===== */
.detail-filters {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    gap: 16px;
    flex-wrap: wrap;
}

.filter-group {
    display: flex;
    gap: 12px;
    align-items: center;
}

.filter-select, .filter-input {
    padding: 10px 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-card);
    color: var(--text-primary);
    font-size: 14px;
    cursor: pointer;
}

.search-box {
    position: relative;
    flex: 1;
    max-width: 300px;
}

.search-input {
    width: 100%;
    padding: 10px 14px 10px 40px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-card);
    color: var(--text-primary);
    font-size: 14px;
}

.search-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 14px;
    color: var(--text-muted);
}

.detail-list {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.detail-item {
    display: flex;
    align-items: center;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border-color);
    cursor: pointer;
    transition: var(--transition);
}

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

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

.detail-item-type {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    margin-right: 14px;
    flex-shrink: 0;
}

.detail-item-type.income {
    background: var(--success);
}

.detail-item-type.expense {
    background: var(--danger);
}

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

.detail-item-category {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2px;
}

.detail-item-meta {
    font-size: 12px;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.detail-item-amount {
    font-size: 16px;
    font-weight: 700;
    margin-left: 16px;
    white-space: nowrap;
}

.detail-item-amount.income {
    color: var(--success);
}

.detail-item-amount.expense {
    color: var(--danger);
}

.detail-summary {
    display: flex;
    justify-content: flex-end;
    gap: 24px;
    padding: 16px 20px;
    margin-top: 16px;
    background: var(--bg-card);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    font-size: 14px;
    color: var(--text-secondary);
}

.income-text {
    color: var(--success);
}

.expense-text {
    color: var(--danger);
}

.balance-text {
    color: var(--secondary);
}

/* ===== Modal ===== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 480px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
    font-size: 18px;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-muted);
    cursor: pointer;
    line-height: 1;
}

.modal-close:hover {
    color: var(--text-primary);
}

.modal .record-form {
    padding: 24px;
}

.form-actions {
    display: flex;
    gap: 12px;
    margin-top: 8px;
}

.form-actions .btn {
    flex: 1;
}

/* ===== Toast ===== */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--text-primary);
    color: white;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-size: 14px;
    z-index: 2000;
    opacity: 0;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-lg);
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* ===== Empty State ===== */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

.empty-state-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.empty-state-text {
    font-size: 14px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: -240px;
        height: 100vh;
    }
    
    .sidebar.open {
        left: 0;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .summary-cards {
        grid-template-columns: 1fr;
    }
    
    .charts-grid {
        grid-template-columns: 1fr;
    }
    
    .category-select {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .detail-filters {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-group {
        flex-wrap: wrap;
    }
    
    .search-box {
        max-width: none;
    }
    
    .detail-summary {
        flex-direction: column;
        gap: 8px;
        align-items: flex-start;
    }
    
    .page {
        padding: 16px;
    }
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}