:root {
    --bg-color: #f8fafc;
    --card-bg: rgba(255, 255, 255, 0.8);
    --primary: #10b981; /* Emerald for ROAS */
    --secondary: #3b82f6; /* Blue for Spend */
    --text-main: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    background-image: 
        radial-gradient(at 0% 0%, rgba(16, 185, 129, 0.05) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(59, 130, 246, 0.05) 0px, transparent 50%);
    min-height: 100vh;
}

.app-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    margin-bottom: 2.5rem;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    color: #0f172a;
}

header p {
    color: var(--text-muted);
}

.date-range {
    background: var(--card-bg);
    padding: 0.5rem 1rem;
    border-radius: 99px;
    border: 1px solid var(--border);
    font-size: 0.875rem;
    font-weight: 500;
}

/* KPI Cards */
.kpi-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2.5rem;
}

.kpi-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: var(--glass-shadow);
    transition: transform 0.2s;
}

.kpi-card:hover {
    transform: translateY(-4px);
}

.kpi-card .label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.kpi-card .value {
    font-size: 1.5rem;
    font-weight: 700;
    color: #0f172a;
}

#kpi-roas .value { color: var(--primary); }

/* Charts */
.charts-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.chart-container {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.25rem;
    box-shadow: var(--glass-shadow);
    height: 320px;
    display: flex;
    flex-direction: column;
}

.chart-container h3 {
    margin-bottom: 1rem;
    font-size: 1rem;
    font-weight: 600;
}

.chart-container canvas {
    flex: 1;
    width: 100% !important;
    height: 100% !important;
}

/* Table */
.table-section {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: var(--glass-shadow);
}

.table-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.table-controls button {
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
    background: white;
    cursor: pointer;
    font-weight: 500;
    margin-left: 0.5rem;
    transition: all 0.2s;
}

.table-controls button.active {
    background: #0f172a;
    color: white;
    border-color: #0f172a;
}

.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

th {
    text-align: left;
    padding: 1rem;
    border-bottom: 2px solid var(--border);
    color: var(--text-muted);
    font-weight: 600;
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--border);
}

tr:last-child td {
    border-bottom: none;
}

tr:hover td {
    background: rgba(0,0,0,0.01);
}

footer {
    margin-top: 3rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    padding-bottom: 2rem;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .app-container { padding: 1rem; }
    header { flex-direction: column; align-items: flex-start; gap: 1rem; }
    .charts-section { grid-template-columns: 1fr; }
}