html, body, main, header, footer {
  padding: 0px;
  margin: 0px;
}

/* ==================== 应用容器 ==================== */

#app {
  max-width: 600px;
  margin: 0 auto;
  padding: 20px 16px 40px;
}

#app-title {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  color: #1a73e8;
  margin-bottom: 4px;
}

#app-subtitle {
  text-align: center;
  font-size: 0.95rem;
  color: #666;
  margin-bottom: 24px;
}

/* ==================== 卡片 ==================== */

.card {
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  padding: 20px;
  margin-bottom: 16px;
}

.card-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: #333;
  margin-bottom: 8px;
}

.card-highlight {
  background: linear-gradient(135deg, #f0f7ff 0%, #e8f0fe 100%);
  border: 2px solid #1a73e8;
}

/* ==================== 日期输入 ==================== */

.date-input {
  width: 100%;
  padding: 10px 14px;
  border: 2px solid #e0e0e0;
  border-radius: 8px;
  font-size: 1rem;
  color: #333;
  box-sizing: border-box;
  transition: border-color 0.2s;
  background: #fafafa;
}

.date-input:focus {
  outline: none;
  border-color: #1a73e8;
  background: #fff;
}

/* ==================== 当前时间 ==================== */

.datetime-display {
  font-size: 1.15rem;
  font-weight: 500;
  color: #1a73e8;
  text-align: center;
  padding: 10px 0;
  background: #f8fbff;
  border-radius: 8px;
}

/* ==================== 倒计时网格 ==================== */

.countdown-grid {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 12px;
}

.countdown-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 64px;
}

.countdown-number {
  font-size: 2.4rem;
  font-weight: 800;
  color: #1a73e8;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.countdown-unit {
  font-size: 0.85rem;
  color: #888;
  margin-top: 2px;
}

.countdown-total {
  text-align: center;
  font-size: 1.05rem;
  color: #555;
  font-weight: 500;
}

.countdown-status {
  text-align: center;
  font-size: 0.95rem;
  margin-top: 6px;
  font-weight: 500;
}

.status-future {
  color: #1a73e8;
}

.status-today {
  color: #e67e22;
}

.status-past {
  color: #999;
}

/* ==================== 进度条 ==================== */

.progress-container {
  display: flex;
  align-items: center;
  gap: 12px;
}

.progress-bar-bg {
  flex: 1;
  height: 20px;
  background: #e8e8e8;
  border-radius: 10px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #4caf50 0%, #8bc34a 30%, #ffc107 60%, #ff9800 80%, #f44336 100%);
  border-radius: 10px;
  transition: width 0.5s ease;
}

.progress-text {
  font-size: 1.1rem;
  font-weight: 700;
  color: #333;
  min-width: 52px;
  text-align: right;
}

.progress-detail {
  text-align: center;
  font-size: 0.85rem;
  color: #888;
  margin-top: 8px;
}

/* ==================== 预设日期标签 ==================== */

.preset-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.preset-tag {
  padding: 6px 14px;
  border: 1px solid #d0d0d0;
  border-radius: 20px;
  font-size: 0.9rem;
  background: #fff;
  color: #444;
  cursor: pointer;
  transition: all 0.2s;
}

.preset-tag:hover {
  border-color: #1a73e8;
  color: #1a73e8;
  background: #f0f7ff;
}

.preset-tag:active {
  transform: scale(0.96);
}

/* ==================== 操作按钮 ==================== */

#card-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  background: transparent;
  box-shadow: none;
  padding: 0 20px;
}

.btn-action {
  flex: 1;
  max-width: 180px;
  padding: 12px 20px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  background: #1a73e8;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}

.btn-action:hover {
  background: #1557b0;
}

.btn-action:active {
  transform: scale(0.97);
}

.btn-reset {
  background: #f5f5f5;
  color: #666;
  border: 1px solid #ddd;
}

.btn-reset:hover {
  background: #eee;
  color: #333;
}

/* ==================== 简介区域 ==================== */

#features, #scenarios, #FAQ {
  max-width: 600px;
  margin: 0 auto;
  padding: 16px 20px;
}

#features h2, #scenarios h2, #FAQ h2 {
  font-size: 1.2rem;
  color: #333;
  margin-bottom: 10px;
  border-bottom: 2px solid #1a73e8;
  padding-bottom: 6px;
  display: inline-block;
}

#features p {
  color: #555;
  line-height: 1.7;
  font-size: 0.95rem;
}

#scenarios ul {
  padding-left: 18px;
  color: #555;
  line-height: 1.8;
  font-size: 0.95rem;
}

#scenarios li {
  margin-bottom: 6px;
}

#FAQ dl {
  margin: 0;
}

#FAQ dt {
  font-weight: 600;
  color: #333;
  margin-top: 12px;
  margin-bottom: 4px;
  font-size: 0.95rem;
}

#FAQ dd {
  margin-left: 0;
  color: #666;
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 8px;
}

/* ==================== 响应式设计 ==================== */

@media (max-width: 768px) {
  #app {
    padding: 16px 12px 32px;
  }

  #app-title {
    font-size: 1.6rem;
  }

  .card {
    padding: 16px;
  }

  .countdown-number {
    font-size: 2rem;
  }

  .countdown-grid {
    gap: 8px;
  }

  .countdown-item {
    min-width: 54px;
  }
}

@media (max-width: 480px) {
  #app {
    padding: 12px 8px 24px;
  }

  #app-title {
    font-size: 1.4rem;
  }

  .countdown-number {
    font-size: 1.6rem;
  }

  .countdown-item {
    min-width: 44px;
  }

  .countdown-unit {
    font-size: 0.75rem;
  }

  .preset-tags {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .preset-tag {
    flex-shrink: 0;
  }

  .btn-action {
    font-size: 0.9rem;
    padding: 10px 16px;
  }
}