:root {
    --bg-0: #091824;
    --bg-1: #123247;
    --panel: rgba(9, 20, 35, 0.78);
    --border: rgba(153, 216, 247, 0.22);
    --text-main: #eff9ff;
    --text-muted: #a3cad8;
    --accent: #45f0c2;
    --accent-warm: #ffd166;
    --danger: #f95d6a;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: "Space Grotesk", sans-serif;
    color: var(--text-main);
    background: radial-gradient(circle at 12% 15%, #295977 0%, transparent 45%),
    radial-gradient(circle at 92% 8%, #1d6a67 0%, transparent 45%),
    linear-gradient(140deg, var(--bg-0), var(--bg-1));
}

.bg-grid {
    position: fixed;
    inset: 0;
    background-image: linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
    background-size: 28px 28px;
    pointer-events: none;
}

.container {
    position: relative;
    z-index: 1;
    max-width: 1180px;
    margin: 0 auto;
    padding: 28px 20px 48px;
}

.hero {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: flex-start;
    margin-bottom: 24px;
}

.hero h1 {
    margin: 0 0 8px;
    font-size: clamp(1.9rem, 2.5vw, 2.9rem);
    letter-spacing: 0.03em;
}

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

.eyebrow {
    margin: 0 0 8px;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    color: var(--accent);
    font-size: 0.75rem;
}

.status-pill {
    margin-top: 8px;
    border: 1px solid var(--border);
    background: rgba(12, 43, 59, 0.65);
    border-radius: 999px;
    padding: 8px 14px;
    color: var(--text-muted);
    font-family: "IBM Plex Mono", monospace;
    font-size: 0.8rem;
}

.panel {
    border-radius: 18px;
    border: 1px solid var(--border);
    background: var(--panel);
    backdrop-filter: blur(10px);
    box-shadow: 0 18px 45px rgba(0, 0, 0, 0.22);
}

.controls {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    padding: 18px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 7px;
}

.field label {
    font-weight: 600;
    color: var(--text-muted);
}

select, input[type="range"], button {
    width: 100%;
    border: 1px solid rgba(146, 223, 241, 0.33);
    border-radius: 12px;
    background: rgba(16, 41, 60, 0.9);
    color: var(--text-main);
    padding: 10px;
    font-family: inherit;
}

input[type="range"] {
    padding: 0;
}

#minutes-label {
    color: var(--accent-warm);
    font-family: "IBM Plex Mono", monospace;
    font-size: 0.85rem;
}

.summary-grid {
    margin-top: 18px;
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.metric-card {
    padding: 16px;
}

.metric-card h2 {
    margin: 0 0 8px;
    font-size: 0.92rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.11em;
}

.metric-card p {
    margin: 0;
    font-size: clamp(1.35rem, 2vw, 1.95rem);
    font-weight: 700;
}

.chart-panel {
    margin-top: 18px;
    padding: 16px;
}

.panel-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 12px;
}

.panel-head h2 {
    margin: 0;
    font-size: 1.12rem;
}

button {
    width: auto;
    cursor: pointer;
    font-weight: 600;
    background: linear-gradient(120deg, #0a7b77, #0f6dc2);
}

button:hover {
    filter: brightness(1.08);
}

.feedback {
    min-height: 20px;
    margin-bottom: 8px;
    font-size: 0.92rem;
    color: var(--text-muted);
}

.feedback.error {
    color: var(--danger);
}

#chart {
    height: min(62vh, 560px);
}

@media (max-width: 980px) {
    .controls {
        grid-template-columns: 1fr;
    }

    .summary-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 620px) {
    .hero {
        flex-direction: column;
    }

    .summary-grid {
        grid-template-columns: 1fr;
    }
}