/* =========================
   Body & wrapper
========================= */
body {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: linear-gradient(135deg, #ff9a9e, #fad0c4);
  font-family: system-ui;
  padding: 20px;
  margin: 0;
}

.wrapper {
  position: relative;
  width: 100%;
  max-width: 320px;
  perspective: 800px;
}

/* =========================
   Background Balloons
========================= */
.balloon-bg-container {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  pointer-events: none;
  z-index: 0; /* behind card */
  overflow: visible;
}

.balloon-bg {
  position: absolute;
  bottom: -50px;
  width: 25px;
  height: 35px;
  background: radial-gradient(circle at 50% 50%, #ff4757, #ff1f3f);
  border-radius: 50% 50% 50% 50%;
  animation: floatUpBg 6s linear forwards;
}

.balloon-bg::after {
  content: "";
  position: absolute;
  width: 2px;
  height: 20px;
  background: #ff1f3f;
  bottom: -20px;
  left: 50%;
  transform: translateX(-50%);
}

@keyframes floatUpBg {
  0% {
    transform: translateY(0) scale(0.8);
    opacity: 1;
  }
  100% {
    transform: translateY(-300px) scale(1);
    opacity: 0;
  }
}

/* =========================
   Card / Envelope
========================= */
.card {
  position: relative;
  width: 320px;
  min-height: 220px;
  background: #ff6b81;
  border-radius: 12px;
  cursor: pointer;
  overflow: hidden;
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
  transition:
    background 0.6s ease,
    transform 0.6s ease,
    box-shadow 0.6s ease;
  z-index: 1;
}

/* Open state: white card & scale up */
.card.open {
  background: white;
  transform: scale(1.05);
}

/* Hover effect when opened */
.card.open:hover {
  transform: scale(1.1);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

/* =========================
   Flap
========================= */
.flap {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: #ff4757;
  clip-path: polygon(0 0, 50% 60%, 100% 0);
  transform-origin: top;
  transition: transform 0.6s ease;
  z-index: 2;
}

.card.open .flap {
  transform: rotateX(-180deg);
}

/* =========================
   Message
========================= */
.message {
  position: relative;
  text-align: center;
  padding: 40px 20px 30px;
  color: white;
  opacity: 0;
  transition:
    opacity 0.6s ease,
    color 0.6s ease;
}

.card.open .message {
  opacity: 1;
  color: #333;
}

.message h1 {
  font-size: 22px;
  margin-bottom: 10px;
}
.message p {
  font-size: 15px;
  line-height: 1.4;
}
.signature {
  margin-top: 10px;
  font-weight: bold;
}

/* Mobile adjustments */
@media (max-width: 400px) {
  .message h1 {
    font-size: 18px;
  }
  .message p {
    font-size: 14px;
  }
}

/* =========================
   Hearts
========================= */
.hearts {
  position: absolute;
  bottom: 0;
  left: 50%;
  pointer-events: none;
}

.heart {
  position: absolute;
  width: 12px;
  height: 12px;
  background: red;
  transform: rotate(45deg);
  animation: float 2.5s forwards;
}

.heart:before,
.heart:after {
  content: "";
  position: absolute;
  width: 12px;
  height: 12px;
  background: red;
  border-radius: 50%;
}

.heart:before {
  top: -6px;
  left: 0;
}
.heart:after {
  left: -6px;
  top: 0;
}

@keyframes float {
  0% {
    transform: translateY(0) rotate(45deg);
    opacity: 1;
  }
  100% {
    transform: translateY(-200px) rotate(45deg);
    opacity: 0;
  }
}

.signature {
  font-weight: bold;
  font-size: 18px;
}