html, body {
  margin: 0;
  overflow: hidden;
}

#app-boot-screen {
  position: fixed;
  inset: 0;
  z-index: 99999;
  display: grid;
  place-items: center;
  /* 提取自咖啡杯图标的静谧灰蓝色 */
  background: #c5d2df; 
  opacity: 1;
  transition: opacity 500ms ease, transform 600ms cubic-bezier(0.4, 0, 0.2, 1);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
}

#app-boot-screen.is-leaving {
  opacity: 0;
  transform: scale(1.05);
  pointer-events: none;
}

.app-boot-stage {
  position: relative;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: min(100%, 360px);
}

/* ================= 咖啡杯与热气动画 ================= */
.boot-coffee-cup {
  position: relative;
  width: 180px;
  height: 165px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-end;
  margin-bottom: 22px;
}

.coffee-steams {
  position: absolute;
  top: -10px;
  display: flex;
  gap: 2px;
  justify-content: center;
  height: 90px;
  width: 108px;
}

.steam {
  opacity: 0;
  transform-origin: bottom;
  animation: steam-rise 3s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}

/* 三缕热气错开时间与高度 */
.steam-left { width: 30px; height: 78px; animation-delay: 0.2s; margin-top: 14px; }
.steam-mid { width: 36px; height: 92px; animation-delay: 0s; }
.steam-right { width: 30px; height: 76px; animation-delay: 0.6s; margin-top: 18px; }

@keyframes steam-rise {
  0% { opacity: 0; transform: translateY(15px) scale(0.9) skewX(5deg); }
  20% { opacity: 0.8; }
  60% { opacity: 0.6; transform: translateY(-10px) scale(1.1) skewX(-5deg); }
  100% { opacity: 0; transform: translateY(-30px) scale(1.2) skewX(0); }
}

.cup-body {
  width: 180px;
  height: 135px;
  z-index: 2;
}

/* ================= 文字与进度条 ================= */
.boot-title {
  margin: 0;
  font-size: 24px;
  font-weight: 700;
  color: #43516a;
  letter-spacing: 2px;
}

.app-boot-label {
  margin: 12px 0 0;
  color: #7a8ba3;
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 1px;
}

.app-boot-progress-wrap {
  width: 75%;
  margin-top: 35px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.app-boot-progress {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.4);
  border-radius: 999px;
  overflow: hidden;
}

.app-boot-progress span {
  display: block;
  width: 0%;
  height: 100%;
  /* 进度条改为醇厚的咖啡棕色渐变 */
  background: linear-gradient(90deg, #9e663e, #5c361c);
  border-radius: 999px;
  transition: width 150ms ease-out;
}

.app-boot-percent {
  font-size: 13px;
  font-weight: 600;
  color: #7a8ba3;
  font-family: "Courier New", monospace;
}