:root {
  --bg: #0f1419;
  --card: #1a2332;
  --accent: #e07a5f;
  --green: #40916c;
  --text: #f1f5f9;
  --muted: #94a3b8;
  --border: #2d3a4f;
}

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

body {
  font-family: "Segoe UI", "Hiragino Sans", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  padding: 1rem;
  max-width: 960px;
  margin: 0 auto;
}

.header { margin-bottom: 1.5rem; }
.header h1 { font-size: 1.5rem; }
.sub { color: var(--muted); font-size: 0.9rem; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  margin-bottom: 1rem;
}

.card h2 { font-size: 1.1rem; margin-bottom: 0.75rem; }
.hint { color: var(--muted); font-size: 0.85rem; margin-bottom: 1rem; }

label { display: block; font-size: 0.85rem; color: var(--muted); margin: 0.75rem 0 0.25rem; }
input {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
}

.btn {
  margin-top: 1rem;
  padding: 0.65rem 1.25rem;
  border: none;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
}
.btn.primary { background: var(--accent); color: #fff; }
.btn.primary:hover { filter: brightness(1.1); }

.error { color: #f87171; font-size: 0.9rem; margin-top: 0.5rem; }

.stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1rem;
}
.stat { text-align: center; }
.stat-label { display: block; color: var(--muted); font-size: 0.8rem; }
.stat-value { display: block; font-size: 2rem; font-weight: 700; color: var(--green); }

.charts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}
.chart-box {
  background: var(--bg);
  border-radius: 8px;
  padding: 0.75rem;
}
.chart-box h3 { font-size: 0.9rem; margin-bottom: 0.5rem; color: var(--accent); }

.tag-list { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.tag {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  font-size: 0.85rem;
}

.session-item {
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 0;
}
.session-item:last-child { border-bottom: none; }
.session-date { color: var(--muted); font-size: 0.8rem; }
.session-body { font-size: 0.9rem; margin-top: 0.25rem; }