:root {
    --bg-main: #0f172a;
    --bg-card: #1e293b;
    --border-color: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    
    --color-temp: #f97316;
    --color-use: #06b6d4;
    --transition-smooth: all 0.2s ease-in-out;
}

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

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    font-family: 'Outfit', sans-serif;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 2rem 1.5rem;
}

.container {
    width: 100%;
    max-width: 900px;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

h1 {
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.selectors {
    display: flex;
    gap: 0.25rem;
    background: #1e293b;
    border: 1px solid var(--border-color);
    padding: 0.25rem;
    border-radius: 8px;
}

.btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 600;
    padding: 0.4rem 1.25rem;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition-smooth);
}

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

.btn.active {
    background: #334155;
    color: var(--text-primary);
}

.chart-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    position: relative;
    height: 450px;
}

@media (max-width: 600px) {
    header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .selectors {
        width: 100%;
    }
    
    .btn {
        flex: 1;
        text-align: center;
    }
    
    .chart-card {
        height: 350px;
    }
}