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

body {
  background: var(--tg-theme-bg-color, #fff);
  color: var(--tg-theme-text-color, #000);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  padding-bottom: 80px; /* space for MainButton */
}

.container {
  max-width: 480px;
  margin: 0 auto;
  padding: 16px;
}

.section {
  margin-bottom: 20px;
}

/* Input */
.input-section label {
  font-size: 13px;
  color: var(--tg-theme-hint-color, #999);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
  display: block;
}

.input-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

#weight-input {
  flex: 1;
  font-size: 36px;
  font-weight: 600;
  padding: 12px 16px;
  border: 2px solid var(--tg-theme-hint-color, #ddd);
  border-radius: 12px;
  background: var(--tg-theme-secondary-bg-color, #f5f5f5);
  color: var(--tg-theme-text-color, #000);
  outline: none;
  transition: border-color 0.2s;
  -webkit-appearance: none;
}

#weight-input:focus {
  border-color: var(--tg-theme-button-color, #007aff);
}

#weight-input::placeholder {
  color: var(--tg-theme-hint-color, #ccc);
}

.unit {
  font-size: 20px;
  color: var(--tg-theme-hint-color, #999);
  font-weight: 500;
}

/* Period selector */
.period-selector {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.period-btn {
  flex: 1;
  padding: 8px;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  background: var(--tg-theme-secondary-bg-color, #f0f0f0);
  color: var(--tg-theme-hint-color, #666);
  transition: all 0.2s;
}

.period-btn.active {
  background: var(--tg-theme-button-color, #007aff);
  color: var(--tg-theme-button-text-color, #fff);
}

/* Chart */
.chart-wrapper {
  background: var(--tg-theme-secondary-bg-color, #f8f8f8);
  border-radius: 12px;
  padding: 12px;
}

/* Stats */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  margin-top: 12px;
}

.stat-item {
  text-align: center;
  padding: 8px 4px;
  background: var(--tg-theme-secondary-bg-color, #f5f5f5);
  border-radius: 8px;
}

.stat-value {
  font-size: 16px;
  font-weight: 600;
}

.stat-label {
  font-size: 11px;
  color: var(--tg-theme-hint-color, #999);
  margin-top: 2px;
}

.stat-positive { color: #e53935; }
.stat-negative { color: #43a047; }

/* History */
.history-section h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 10px;
}

.history-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 12px;
  border-radius: 8px;
  margin-bottom: 4px;
}

.history-row:nth-child(odd) {
  background: var(--tg-theme-secondary-bg-color, #f8f8f8);
}

.history-date {
  font-size: 14px;
  color: var(--tg-theme-hint-color, #888);
}

.history-weight {
  font-size: 16px;
  font-weight: 600;
}

.history-delta {
  font-size: 12px;
  margin-left: 6px;
}

/* Loading */
.loading {
  text-align: center;
  padding: 40px;
  color: var(--tg-theme-hint-color, #999);
}