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

body{
  min-height:100vh;
  background:#faf7f2;
  color:#4b4038;
  font-family:Arial,sans-serif;
  overflow-x:hidden;
}

.page{
  min-height:100vh;
  display:flex;
  flex-direction:column;
  justify-content:center;
  align-items:center;
  padding:20px;
}

.card{
  width:240px;
  background:#fff;
  border-radius:24px;
  padding:14px 13px;
  box-shadow:0 15px 40px rgba(0,0,0,.08);
  text-align:center;
  position:relative;
  z-index:1;
}

h1,h2{
  font-family:Georgia,serif;
  font-size:clamp(0.95rem,4vw,1.25rem);
}

.envelope-wrap{
  width:clamp(100px,35vw,160px);
  margin:14px auto;
  cursor:pointer;
  animation:float 2s ease-in-out infinite;
  -webkit-tap-highlight-color:transparent;
  outline:none;
  user-select:none;
}

.envelope-wrap img{
  width:100%;
  display:block;
}

.open-text{
  color:#7b6d63;
  font-size:0.875rem;
}

.letter{
  display:none;
}

.sorry-text{
  display:none;
  margin-top:10px;
  font-size:0.72rem;
  color:rgba(75,64,56,0.32);
  text-align:center;
  font-style:italic;
}

.cake-photo{
  width:65%;
  border-radius:16px;
  margin:0 auto 10px;
  display:block;
}

.message-box{
  line-height:1.6;
  font-size:clamp(0.78rem,2.8vw,0.875rem);
  text-align:left;
}

.message-box h2{
  margin-bottom:8px;
  text-align:center;
}

.message-box p{
  margin-top:8px;
}

.cat{
  position:fixed;
  z-index:0;
  display:none;
  pointer-events:none;
  filter:drop-shadow(0 12px 20px rgba(0,0,0,.15));
}

.cat.show{
  display:block;
}

.cat-1{ width:clamp(80px,13vw,160px); top:16px;    left:12px;  animation:float1 4s   ease-in-out infinite; }
.cat-2{ width:clamp(80px,13vw,160px); top:16px;    right:12px; animation:float2 5s   ease-in-out infinite; }
.cat-3{ width:clamp(80px,13vw,160px); bottom:16px; left:12px;  animation:float3 4.5s ease-in-out infinite; }
.cat-4{ width:clamp(80px,13vw,160px); bottom:16px; right:12px; animation:float2 4s   ease-in-out infinite; }
.cat-5{ width:clamp(70px,11vw,140px); top:40%;     left:8px;   animation:float3 5s   ease-in-out infinite; }
.cat-6{ width:clamp(70px,11vw,140px); top:40%;     right:8px;  animation:float1 4.5s ease-in-out infinite; }

@media(max-width:700px){
  .page{ padding:20px; }
}

@media(max-width:500px){
  .page{ padding:16px; }
  .card{ width:220px; padding:13px 12px; border-radius:18px; }
  .cake-photo{ width:75%; }
}

@media(max-width:380px){
  .page{ padding:12px; }
  .card{ width:190px; padding:12px; }
}

@media(max-width:280px){
  .page{ padding:12px; }
  .cat{ display:none !important; }
}

@keyframes float{
  0%,100%{ transform:translateY(0); }
  50%{     transform:translateY(-8px); }
}
@keyframes float1{
  0%,100%{ transform:translateY(0) rotate(-5deg); }
  50%{     transform:translateY(-14px) rotate(5deg); }
}
@keyframes float2{
  0%,100%{ transform:translateY(0) rotate(4deg); }
  50%{     transform:translateY(-11px) rotate(-4deg); }
}
@keyframes float3{
  0%,100%{ transform:translateY(0); }
  50%{     transform:translateY(-16px); }
}

.fade-out{
  animation:fadeOut 0.35s ease forwards;
}
.letter-enter{
  animation:letterPop 0.5s cubic-bezier(0.34,1.56,0.64,1) forwards;
}
.item-enter{
  opacity:0;
  animation:itemSlide 0.5s ease forwards;
}

@keyframes fadeOut{
  0%  { opacity:1; transform:scale(1);    }
  100%{ opacity:0; transform:scale(0.95); }
}
@keyframes letterPop{
  0%  { opacity:0; transform:scale(0.9) translateY(20px); }
  100%{ opacity:1; transform:scale(1)   translateY(0);    }
}
@keyframes itemSlide{
  0%  { opacity:0; transform:translateY(16px); }
  100%{ opacity:1; transform:translateY(0);    }
}