:root {
    --bg: #f8fafc;
    --ink: #0f172a;
    --muted: #64748b;
    --line: #e2e8f0;
    --card: #ffffff;
    --import: #b91c1c;   /* drawing from grid */
    --export: #15803d;   /* solar surplus */
    --grid-line: #cbd5e1;
}

* { box-sizing: border-box; }

body {
    font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
    background: var(--bg);
    color: var(--ink);
    margin: 0;
    padding: 2rem 1rem;
    display: flex;
    justify-content: center;
}

main { width: 100%; max-width: 38rem; }

h1 { font-size: 1.5rem; margin: 0 0 1.25rem; text-align: center; }

/* --- Live readout --- */
.live { text-align: center; margin-bottom: 1.5rem; }

.direction {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
}
.direction.importing { color: var(--import); }
.direction.exporting { color: var(--export); }

.watts {
    margin: 0.25rem 0;
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1;
}
.watts .unit { font-size: 1.5rem; font-weight: 500; color: var(--muted); }
.importing .watts, .live.importing #watts { color: var(--import); }

.amps { margin: 0; color: var(--muted); }

/* --- Today's totals --- */
.today {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.75rem;
    margin-bottom: 1.75rem;
}
.card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 0.6rem;
    padding: 0.75rem 0.5rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}
.card .label { font-size: 0.75rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; }
.card .value { font-size: 1.5rem; font-weight: 700; }
.card .card-unit { font-size: 0.75rem; color: var(--muted); }

@media (max-width: 30rem) {
    .today { grid-template-columns: repeat(2, 1fr); }
    .watts { font-size: 2.75rem; }
}

/* --- Chart --- */
.chart-section { background: var(--card); border: 1px solid var(--line); border-radius: 0.6rem; padding: 1rem; }
.range-switch { display: flex; gap: 0.5rem; margin-bottom: 0.75rem; }
.range-switch button {
    flex: 1;
    padding: 0.4rem 0.5rem;
    border: 1px solid var(--line);
    background: #fff;
    color: var(--ink);
    border-radius: 0.4rem;
    cursor: pointer;
    font: inherit;
}
.range-switch button.active { background: var(--ink); color: #fff; border-color: var(--ink); }
canvas { width: 100%; height: auto; display: block; }
.chart-legend { margin: 0.5rem 0 0; font-size: 0.8rem; color: var(--muted); text-align: center; }

.updated { text-align: center; color: var(--muted); font-size: 0.8rem; margin: 1rem 0 0; }
.footer { text-align: center; color: var(--muted); font-size: 0.8rem; margin-top: 1.5rem; }