/* ========================================
   LAYOUT & STRUCTURE
   ======================================== */

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

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

body {
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-background);
    overflow-x: hidden;
}

/* App Container */
.app {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
}

.header-content {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-lg);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    flex: 1;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.app-title {
    font-family: var(--font-family-heading);
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-primary-light);
    margin: 0;
    white-space: nowrap;
}

/* Period Selector */
.period-selector {
    display: flex;
    gap: var(--spacing-xs);
    background-color: var(--color-surface-light);
    padding: var(--spacing-xs);
    border-radius: var(--radius-md);
}

.period-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.period-btn:hover {
    color: var(--color-text-primary);
    background-color: rgba(255, 255, 255, 0.05);
}

.period-btn.active {
    color: var(--color-primary-light);
    background-color: var(--color-primary);
    box-shadow: var(--shadow-sm);
}

/* Main Content */
.main-content {
    flex: 1;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: var(--spacing-xl);
    width: 100%;
}

/* Dashboard Overview */
.dashboard-overview {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), transparent);
    opacity: 0.8;
}

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

.balance-card { --accent-color: var(--color-balance); }
.income-card { --accent-color: var(--color-income); }
.expense-card { --accent-color: var(--color-expense); }
.savings-card { --accent-color: var(--color-secondary); }

.stat-label {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--spacing-sm);
}

.stat-value {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-xs);
}

.stat-change,
.stat-trend,
.stat-subtitle {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

/* Alerts Section */
.alerts-section {
    margin-bottom: var(--spacing-xl);
}

/* Main Grid */
.main-grid {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: var(--spacing-xl);
}

.main-left,
.main-right {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

/* Card Component */
.card {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

.card-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-md);
}

.card-title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    margin: 0;
}

.card-subtitle {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
}

.card-body {
    padding: var(--spacing-lg);
}

/* Analytics Tabs */
.analytics-tabs {
    display: flex;
    gap: var(--spacing-sm);
}

.tab-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.tab-btn.active {
    color: var(--color-primary-light);
    border-bottom-color: var(--color-primary-light);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Search & Filter */
.search-filter {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.search-input,
.filter-select {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
    background-color: var(--color-surface-light);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    outline: none;
    transition: border-color var(--transition-fast);
}

.search-input {
    flex: 1;
    min-width: 200px;
}

.filter-select {
    min-width: 140px;
}

.search-input:focus,
.filter-select:focus {
    border-color: var(--color-primary);
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-lg);
}

/* Responsive Design */
@media (max-width: 1200px) {
    .main-grid {
        grid-template-columns: 1fr;
    }

    .card {
        max-width: 400px;
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        align-items: stretch;
    }

    .header-left {
        flex-direction: column;
        align-items: stretch;
        gap: var(--spacing-md);
    }

    .app-title {
        text-align: center;
    }

    .period-selector {
        justify-content: center;
    }

    .header-right {
        justify-content: center;
    }

    .dashboard-overview {
        grid-template-columns: 1fr;
    }

    .search-filter {
        flex-direction: column;
    }

    .search-input,
    .filter-select {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: var(--spacing-md);
    }

    .stat-value {
        font-size: var(--font-size-2xl);
    }

    .period-selector {
        flex-direction: column;
    }

    .period-btn {
        text-align: center;
    }
}