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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: #f5f6fa;
  color: #333;
  min-height: 100vh;
}

.container {
  max-width: 700px;
  margin: 0 auto;
  padding: 16px;
}

h1 {
  font-size: 1.4rem;
  color: #2c3e50;
  text-align: center;
  padding: 16px 0 8px;
  border-bottom: 2px solid #3498db;
  margin-bottom: 20px;
}

h2 {
  font-size: 1rem;
  color: #555;
  margin-bottom: 12px;
}

section {
  background: #fff;
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

.form-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.form-row label {
  width: 120px;
  font-size: 0.9rem;
  color: #555;
  flex-shrink: 0;
}

.form-row input,
.form-row select {
  flex: 1;
  padding: 8px 10px;
  border: 1px solid #ddd;
  border-radius: 6px;
  font-size: 1rem;
}

.btn-primary {
  width: 100%;
  padding: 12px;
  background: #3498db;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  cursor: pointer;
  margin-top: 4px;
  transition: background 0.2s;
}

.btn-primary:hover {
  background: #2980b9;
}

.btn-secondary {
  padding: 8px 16px;
  background: #ecf0f1;
  color: #333;
  border: 1px solid #ccc;
  border-radius: 6px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-secondary:hover {
  background: #dde1e7;
}

.peak-section {
  background: #eaf4fb;
  border-left: 4px solid #3498db;
}

#peakInfo {
  font-size: 1rem;
  color: #2c3e50;
  line-height: 1.6;
}

#peakInfo .peak-label {
  font-weight: bold;
  color: #e74c3c;
}

.chart-section canvas {
  width: 100%;
  height: 220px;
  display: block;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

thead th {
  background: #f0f4f8;
  padding: 8px;
  text-align: left;
  font-size: 0.85rem;
  color: #666;
}

tbody td {
  padding: 8px;
  border-bottom: 1px solid #f0f0f0;
}

.del-btn {
  background: none;
  border: none;
  color: #e74c3c;
  cursor: pointer;
  font-size: 1.1rem;
  padding: 2px 6px;
  border-radius: 4px;
}

.del-btn:hover {
  background: #fde8e8;
}

.date-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid #f0f0f0;
  font-size: 0.95rem;
  cursor: pointer;
  color: #3498db;
}

.date-item:hover {
  background: #f0f8ff;
}

.empty-msg {
  color: #aaa;
  text-align: center;
  padding: 16px 0;
  font-size: 0.9rem;
}

@media (max-width: 480px) {
  .form-row {
    flex-direction: column;
    align-items: flex-start;
  }
  .form-row label {
    width: auto;
  }
  .form-row input,
  .form-row select {
    width: 100%;
  }
}