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

html, body {
  width: 100%;
  height: 100%;
  background-color: #f5f5f7;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  overflow-x: hidden;
}

/* 主容器：PC端居中加阴影展示，手机端铺满全屏 */
.app-landing {
  position: relative;
  width: 100%;
  max-width: 480px; /* 限制最大宽度，在PC上呈现手机体验画面 */
  height: 100vh;
  margin: 0 auto;
  overflow: hidden;
  background-color: #fff;
  box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
  display: flex;
  flex-direction: column;
}

/* 背景图区域 */
.bg-wrapper {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

.background-image {
  width: 100%;
  height: 100%;
  object-fit: cover; /* 保证背景图片不变形，自适应拉伸 */
  object-position: center top;
}

/* 按钮及邀请码浮动操作区 */
.action-container {
  position: absolute;
  bottom: 8%; /* 距离底部 8%，适应绝大多数海报底图位置 */
  left: 50%;
  transform: translateX(-50%);
  width: 85%;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

/* 邀请码盒子 */
.invite-box {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(5px);
  padding: 8px 16px;
  border-radius: 30px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border: 1px solid rgba(255, 255, 255, 0.8);
  transition: transform 0.2s active;
  width: auto;
  max-width: 100%;
}

.invite-box:active {
  transform: scale(0.98);
}

.invite-label {
  font-size: 15px;
  color: #333333;
  font-weight: 500;
}

.invite-code {
  font-size: 20px;
  font-weight: bold;
  color: #e60012; /* 红色醒目高亮 */
  letter-spacing: 1.5px;
  margin: 0 6px;
}

.copy-btn {
  font-size: 11px;
  color: #ffffff;
  background-color: #ff4d4f;
  padding: 2px 8px;
  border-radius: 10px;
  margin-left: 4px;
}

/* 下载按钮 */
.download-btn {
  width: 100%;
  height: 48px;
  line-height: 48px;
  background: linear-gradient(135deg, #ff416c, #ff4b2b);
  color: #ffffff;
  font-size: 18px;
  font-weight: bold;
  text-align: center;
  text-decoration: none;
  border-radius: 24px;
  box-shadow: 0 6px 16px rgba(255, 65, 108, 0.4);
  transition: all 0.2s ease;
  display: block;
}

.download-btn:active {
  opacity: 0.9;
  transform: scale(0.99);
}

/* Toast 提示弹窗 */
.toast {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgba(0, 0, 0, 0.75);
  color: #fff;
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 14px;
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.toast.show {
  opacity: 1;
  visibility: visible;
}

/* 针对大屏 PC 端的微调：如果背景图偏高，可调整操作区高度 */
@media screen and (min-height: 800px) and (min-width: 768px) {
  .action-container {
    bottom: 12%;
  }
}