:root {
  --bg: #f7f1e8;
  --bg-soft: #fffaf4;
  --ink: #5f5247;
  --ink-soft: #8b7a6d;
  --peach: #f7ceb5;
  --cream: #fff4e6;
  --mint: #dbe9d7;
  --blue: #d9e7f2;
  --pink: #f6c3d6;
  --orange: #f6d4a2;
  --shadow: 0 24px 60px rgba(139, 117, 95, 0.14);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  overflow: hidden;
  font-family: "Noto Sans TC", "Baloo 2", sans-serif;
  color: var(--ink);
  background:
    linear-gradient(rgba(247, 241, 232, 0.72), rgba(247, 241, 232, 0.72)),
    url("./images/bg.png") center center / cover no-repeat;
}

.app-shell {
  position: relative;
  min-height: 100vh;
  overflow: hidden;
}

.bg-glow {
  position: absolute;
  width: 36rem;
  height: 36rem;
  border-radius: 50%;
  filter: blur(44px);
  opacity: 0.48;
  pointer-events: none;
}

.bg-glow-left {
  top: -12rem;
  left: -10rem;
  background: radial-gradient(circle, rgba(245, 220, 191, 0.75), transparent 66%);
}

.bg-glow-right {
  right: -12rem;
  bottom: -14rem;
  background: radial-gradient(circle, rgba(234, 218, 198, 0.82), transparent 66%);
}

.scene {
  position: relative;
  min-height: 100vh;
  overflow: hidden;
  perspective: 1400px;
  background: linear-gradient(rgba(247, 241, 232, 0.28), rgba(247, 241, 232, 0.28));
}

.instruction-card {
  position: absolute;
  top: 1.2rem;
  left: 1.2rem;
  z-index: 10;
  padding: 0.7rem 0.9rem;
  border-radius: 16px;
  background: rgba(255, 252, 246, 0.72);
  backdrop-filter: blur(12px);
  box-shadow: 0 12px 28px rgba(139, 117, 95, 0.1);
  color: var(--ink);
  font-size: 0.9rem;
  line-height: 1.45;
}

.instruction-card p {
  margin: 0;
}

.camera-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  overflow: hidden;
  pointer-events: none;
}

.camera-hidden video,
.camera-hidden canvas {
  width: 1px;
  height: 1px;
}

.decor-layer,
.intro-stage,
.explosion-stage,
.typewriter-stage {
  position: absolute;
  inset: 0;
}

.decor-layer {
  z-index: 6;
  pointer-events: none;
  transform-style: preserve-3d;
}

.decor-stars,
.burst-particles {
  position: absolute;
  inset: 0;
  transform-style: preserve-3d;
}

.decor-star,
.burst-particle {
  position: absolute;
  left: 50%;
  top: 50%;
  will-change: transform, opacity, filter;
  opacity: 0;
  transform-origin: center;
}

.decor-star,
.burst-particle.star {
  width: var(--size, 22px);
  height: var(--size, 22px);
}

.image-star::before,
.image-star::after {
  display: none;
}

.image-star img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
  filter: drop-shadow(0 0 18px rgba(255, 225, 140, 0.72));
}

.decor-star::before,
.decor-star::after,
.burst-particle.star::before,
.burst-particle.star::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 1), rgba(255, 222, 120, 1));
  box-shadow: 0 0 24px rgba(255, 225, 140, 0.72);
}

.decor-star::before,
.burst-particle.star::before {
  width: 24%;
  height: 100%;
}

.decor-star::after,
.burst-particle.star::after {
  width: 100%;
  height: 24%;
}

.intro-stage {
  z-index: 3;
  display: grid;
  place-items: center;
  pointer-events: none;
  overflow: hidden;
}

.push-group {
  position: relative;
  width: min(600px, 78vw);
  height: min(360px, 48vw);
  transform-style: preserve-3d;
  will-change: transform, opacity;
  opacity: 0;
}

.dog-image {
  position: absolute;
  left: 8px;
  bottom: 30px;
  width: min(240px, 30vw);
  height: auto;
  z-index: 1;
}

.cake-stage {
  position: absolute;
  left: 262px;
  bottom: 0;
  width: min(24vw, 290px);
  height: min(29vw, 340px);
  will-change: transform, opacity;
  z-index: 2;
}

.cake {
  position: relative;
  width: 100%;
  height: 100%;
}

.cake-shadow {
  position: absolute;
  left: 50%;
  bottom: 30px;
  width: 260px;
  height: 34px;
  transform: translateX(-50%);
  border-radius: 50%;
  background: rgba(145, 121, 97, 0.18);
  filter: blur(10px);
}

.cake-plate {
  position: absolute;
  left: 50%;
  bottom: 42px;
  width: 250px;
  height: 20px;
  transform: translateX(-50%);
  border-radius: 999px;
  background: linear-gradient(180deg, #fff, #f6eadb);
}

.cake-tier {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 24px;
  background: linear-gradient(180deg, var(--bg-soft), #f0c8a6);
  border: 1px solid rgba(205, 170, 132, 0.28);
}

.cake-tier-bottom {
  bottom: 54px;
  width: 232px;
  height: 100px;
}

.cake-tier-middle {
  bottom: 136px;
  width: 178px;
  height: 82px;
}

.cake-tier-top {
  bottom: 206px;
  width: 130px;
  height: 62px;
}

.cake-icing {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 999px;
  background: linear-gradient(180deg, #fffdf9, #fff0dd);
}

.cake-icing-bottom {
  bottom: 136px;
  width: 232px;
  height: 18px;
}

.cake-icing-middle {
  bottom: 206px;
  width: 178px;
  height: 16px;
}

.cake-icing-top {
  bottom: 258px;
  width: 130px;
  height: 14px;
}

.cake-candle {
  position: absolute;
  left: 50%;
  bottom: 258px;
  width: 14px;
  height: 58px;
  transform: translateX(-50%);
  border-radius: 999px;
  background: repeating-linear-gradient(135deg, #fff6f0 0 8px, #f7c78c 8px 16px);
}

.cake-flame {
  position: absolute;
  left: 50%;
  bottom: 310px;
  width: 24px;
  height: 34px;
  transform: translateX(-50%);
  border-radius: 60% 60% 70% 70%;
  background: radial-gradient(circle at 50% 35%, #fff7be 0 22%, #ffca74 56%, #ff9764 100%);
  filter: drop-shadow(0 0 14px rgba(255, 185, 96, 0.44));
  animation: flame-flicker 1.5s ease-in-out infinite;
}

.explosion-stage {
  z-index: 5;
  pointer-events: none;
}

.photo-container {
  position: absolute;
  inset: 0;
  z-index: 7;
}

.photo-particle {
  position: absolute;
  left: 50%;
  top: 50%;
  width: clamp(62px, 8vw, 118px);
  aspect-ratio: 4 / 5;
  overflow: hidden;
  border-radius: 16px;
  border: 5px solid rgba(255, 255, 255, 0.95);
  box-shadow: 0 12px 28px rgba(128, 111, 92, 0.16);
  background: white;
  opacity: 0;
  will-change: transform, opacity;
}

.photo-particle img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.birthday-title {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%) scale(0.9);
  margin: 0;
  width: min(88vw, 880px);
  font-family: "Moon Dance", "Baloo 2", cursive;
  font-size: clamp(4.1rem, 8.8vw, 7.4rem);
  color: #e77471;
  text-shadow:
    0 8px 20px rgba(231, 116, 113, 0.24),
    0 0 14px rgba(255, 232, 226, 0.36);
  letter-spacing: 0.02em;
  line-height: 1.08;
  opacity: 0;
  z-index: 8;
  will-change: transform, opacity;
  text-align: center;
}

.typewriter-stage {
  z-index: 8;
  display: grid;
  place-items: end center;
  padding-bottom: 4rem;
  pointer-events: none;
}

.paper-card {
  width: min(520px, calc(100vw - 2rem));
  min-height: 210px;
  border-radius: 28px 28px 18px 18px;
  background: linear-gradient(180deg, #fffdf9, #fbf4ea);
  box-shadow: var(--shadow);
  border: 1px solid rgba(214, 186, 156, 0.34);
  opacity: 0;
  transform: translateY(40px) scale(0.96);
  will-change: transform, opacity;
}

.paper-top {
  height: 18px;
  border-radius: 28px 28px 0 0;
  background: linear-gradient(90deg, #efc8a5, #f6dfbf);
}

.paper-body {
  padding: 1.4rem 1.5rem 1.7rem;
  position: relative;
}

.typed-message {
  margin: 0;
  min-height: 7.5rem;
  font-family: "Noto Serif TC", "Noto Sans TC", serif;
  font-weight: 600;
  letter-spacing: 0.02em;
  font-size: clamp(1.45rem, 4vw, 2.3rem);
  line-height: 1.5;
  color: #7a604e;
  white-space: pre-wrap;
}

.typed-message::after {
  content: "";
  display: inline-block;
  width: 0.12em;
  height: 1em;
  margin-left: 0.12em;
  background: currentColor;
  vertical-align: -0.08em;
  animation: blink 1s steps(1) infinite;
}

.paper-signature {
  position: absolute;
  right: 1.3rem;
  bottom: 0.45rem;
  text-align: right;
  font-family: "Noto Serif TC", "Noto Sans TC", serif;
  font-weight: 600;
  font-size: 0.95rem;
  line-height: 1.25;
  color: rgba(95, 82, 71, 0.72);
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 700ms ease, transform 700ms ease;
}

.paper-signature.visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes cake-bob {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-8px);
  }
}

@keyframes flame-flicker {
  0%,
  100% {
    transform: translateX(-50%) scale(1) rotate(-3deg);
  }
  50% {
    transform: translateX(-50%) scale(1.08) rotate(3deg);
  }
}

@keyframes blink {
  0%,
  49% {
    opacity: 1;
  }
  50%,
  100% {
    opacity: 0;
  }
}

@media (max-width: 720px) {
  .dog-cake-group {
    width: min(92vw, 560px);
    height: 360px;
  }

  .dog-image {
    width: 180px;
  }

  .cake-stage {
    width: 280px;
    height: 340px;
  }

  .birthday-title {
    top: 50%;
    white-space: normal;
    text-align: center;
    width: calc(100vw - 2rem);
    font-size: clamp(4.1rem, 16vw, 6.7rem);
  }

  .typewriter-stage {
    padding-bottom: 1.8rem;
  }
}