:root{
  --pink:#F2A6B8;
  --rose:#D4607C;
  --deep:#B8264A;
  --berry:#7E1230;
  --peach:#FBD5DD;
  --cream:#FFF6F7;
  --ink:#6B2A3E;
  --ease-open:cubic-bezier(.65,.02,.25,1);
  --ease-bounce:cubic-bezier(.34,1.56,.64,1);
}

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

/* no blue/grey flash or text selection when tapping on mobile */
*{-webkit-tap-highlight-color:transparent}
html,body,.book,button{-webkit-user-select:none;user-select:none;-webkit-touch-callout:none}
button{touch-action:manipulation}

body{
  min-height:100vh;
  min-height:100dvh;
  overflow-x:hidden;
  font-family:'Josefin Sans',system-ui,sans-serif;
  color:var(--ink);
  background-color:#9c1e3c;
  background-image:
    radial-gradient(circle at 50% 45%,rgba(255,214,224,.5) 0,transparent 55%),
    radial-gradient(circle at 12% 8%,rgba(255,235,240,.7) 0,transparent 40%),
    linear-gradient(165deg,#f6b9c7 0%,#d4607c 38%,#a91d44 72%,#5e0f26 100%);
  background-attachment:fixed;
}

button{font:inherit;border:0;cursor:pointer;background:none;color:inherit}
button:focus-visible{outline:3px dashed #fff;outline-offset:4px}

.ico{display:inline-block;width:1em;height:1em;fill:currentColor;vertical-align:-.125em;flex:none;line-height:1}
.sticker{display:grid;place-items:center;font-size:18px}

/* ============ SCENE ============ */
.scene{
  position:relative;
  min-height:100vh;
  min-height:100dvh;
  display:grid;
  place-items:center;
  padding:35px 15px;
  overflow:hidden;
}

/* ============ PLAYFUL BACKGROUND ============ */
.ambient{position:fixed;inset:0;overflow:hidden;pointer-events:none;z-index:0}

.petal{
  position:absolute;top:-30px;
  width:var(--s,14px);height:calc(var(--s,14px)*1.3);
  background:linear-gradient(135deg,#ffd6df,#e0607e);
  border-radius:100% 0 100% 0;
  opacity:0;
  animation:fall var(--d,14s) linear infinite;
  animation-delay:var(--delay,0s);
}
@keyframes fall{
  0%{transform:translate(0,0) rotate(0);opacity:0}
  10%{opacity:.9}
  30%{transform:translate(var(--drift,40px),35vh) rotate(140deg)}
  60%{transform:translate(calc(var(--drift,40px)*-.6),70vh) rotate(300deg)}
  100%{transform:translate(calc(var(--drift,40px)*.5),115vh) rotate(520deg);opacity:0}
}

.float{position:absolute;opacity:.85;filter:drop-shadow(0 3px 0 rgba(126,18,48,.25));animation:bob 5s ease-in-out infinite}
.float.f1{left:6%;top:12%;font-size:34px;color:var(--pink)}
.float.f2{right:8%;top:16%;font-size:26px;color:#fff;animation-delay:1.2s}
.float.f3{left:10%;bottom:12%;font-size:28px;color:var(--peach);animation-delay:2.4s}
.float.f4{right:10%;bottom:14%;font-size:36px;color:var(--rose);animation-delay:.6s}
@keyframes bob{
  0%,100%{transform:translateY(0) rotate(-6deg)}
  50%{transform:translateY(-16px) rotate(8deg)}
}

/* ============ BOOK ============
   The 3D stage lives on .book. Closed, the cover card is centered.
   ============================== */
.book{
  position:relative;
  z-index:2;
  width:min(900px,94vw);
  height:min(620px,76vh);
  min-height:440px;
  perspective:2000px;
  transform-style:preserve-3d;
  transform:translateX(-25%);
  transition:transform 1.4s var(--ease-open);
}
.book.open{transform:translateX(0)}

/* ---------- OPEN PAGES ---------- */
.pages{
  position:absolute;
  inset:0;
  display:flex;
  opacity:0;
  visibility:hidden;
  border-radius:28px;
  box-shadow:0 22px 0 -6px rgba(184,38,74,.25),0 30px 50px -18px rgba(126,18,48,.4);
  transition:opacity .4s ease,visibility 0s .4s;
}
.book.open .pages{
  opacity:1;
  visibility:visible;
  transition:opacity .8s ease .9s,visibility 0s;
}

.page{
  position:relative;
  width:50%;
  height:100%;
  padding:50px 44px;
  overflow:hidden;
  background-color:var(--cream);
  background-image:radial-gradient(circle,rgba(212,96,124,.16) 2px,transparent 2.5px);
  background-size:22px 22px;
}
.left{border-radius:28px 0 0 28px}
.right{
  border-radius:0 28px 28px 0;
  background-image:
    linear-gradient(90deg,transparent 0,transparent 56px,rgba(212,96,124,.35) 56px,rgba(212,96,124,.35) 58px,transparent 58px),
    repeating-linear-gradient(180deg,transparent 0 33px,rgba(212,96,124,.28) 33px 34px);
  background-color:var(--cream);
}

/* cute dotted inner frame */
.page::before{
  content:"";
  position:absolute;
  inset:16px;
  border:3px double rgba(184,38,74,.5);
  border-radius:20px;
  pointer-events:none;
}

/* center fold */
.fold{
  position:absolute;
  z-index:4;
  left:50%;top:0;bottom:0;
  width:22px;
  transform:translateX(-50%);
  background:linear-gradient(90deg,rgba(126,18,48,.03),rgba(126,18,48,.12) 45%,rgba(255,255,255,.75) 50%,rgba(126,18,48,.12) 55%,rgba(126,18,48,.03));
  pointer-events:none;
}

/* sticker-style corner hearts on the letter page */
.sticker{
  position:absolute;
  z-index:3;
  width:38px;height:38px;
  color:var(--deep);
  background:#fff;
  border-radius:50%;
  padding:9px;
  box-shadow:0 4px 0 rgba(184,38,74,.25);
  transform:rotate(-8deg);
  animation:wiggle 4s ease-in-out infinite;
}
.sticker.tr{top:24px;right:24px;background:var(--peach)}
@keyframes wiggle{
  0%,100%{transform:rotate(-8deg)}
  50%{transform:rotate(6deg)}
}

/* washi tape strips */
.tape{
  position:absolute;
  z-index:5;
  width:86px;height:24px;
  background-color:rgba(244,170,185,.8);
  background-image:repeating-linear-gradient(45deg,transparent 0 7px,rgba(255,255,255,.45) 7px 11px);
  box-shadow:0 1px 2px rgba(126,18,48,.15);
  pointer-events:none;
}

/* ---------- LEFT PAGE: intentionally blank ---------- */
.left-blank{position:relative;height:100%}

/* ---------- RIGHT PAGE ---------- */
.letter-content{
  position:relative;z-index:2;height:100%;
  display:flex;flex-direction:column;justify-content:center;
  padding:6px 8px;
}
.letter-heading{
  font-family:'Pinyon Script',cursive;font-weight:400;
  font-size:42px;line-height:1.1;
  color:var(--berry);
  text-align:center;
  margin:0 0 8px;
  flex:none;
  text-shadow:0 2px 0 #fff;
}
.divider{display:flex;align-items:center;justify-content:center;gap:10px;margin:0 auto 4px;flex:none;color:var(--rose);font-size:15px}
.divider span{width:56px;height:1.5px;background:linear-gradient(90deg,transparent,var(--rose))}
.divider span:last-child{transform:scaleX(-1)}
.paragraph-area{
  flex:1 1 auto;
  min-height:0;
  display:flex;flex-direction:column;
  text-align:center;
  padding:12px 10px;
  overflow-y:auto;
  scrollbar-width:none;
  -ms-overflow-style:none;
}
.paragraph-area::-webkit-scrollbar{display:none}
.paragraph-area .paragraph{margin:auto}
.paragraph{
  font-family:'Cormorant Garamond',serif;font-style:italic;font-weight:600;
  font-size:clamp(21px,2.4vw,28px);
  line-height:1.6;
  max-width:400px;
  white-space:pre-line;
  color:#7a2f45;
}
.paragraph.long{font-size:clamp(16px,1.8vw,20px);line-height:1.45;max-width:440px}
.paragraph .ico{color:var(--deep);font-size:1.1em;vertical-align:-.15em}

/* navigation */
.navigation{display:flex;justify-content:center;gap:12px;margin-top:14px;flex:none}
.nav-btn,
.open-btn{
  display:inline-flex;align-items:center;gap:7px;
  background:linear-gradient(180deg,#cf3f64,#9c1e3c);
  color:#fff;
  font-weight:800;
  border-radius:999px;
  padding:11px 22px;
  font-size:13px;letter-spacing:.3px;
  box-shadow:0 8px 16px -6px rgba(126,18,48,.7),inset 0 1px 0 rgba(255,255,255,.35);
  transition:filter .2s;
  white-space:nowrap;
}
.nav-btn:hover:not(:disabled),
.open-btn:hover{
  filter:brightness(1.1);
}
.nav-btn:active:not(:disabled),
.open-btn:active{transform:translateY(1px)}
.nav-btn:disabled{background:#eec3cc;color:#fff;box-shadow:none;cursor:not-allowed}
.nav-btn .ico{font-size:17px}

/* progress as a cute pill */
.progress{
  display:flex;justify-content:center;
  margin:12px auto 0;
  flex:none;
  background:#fff;
  color:var(--berry);
  font-weight:800;font-size:11px;letter-spacing:2px;
  padding:6px 14px;
  border-radius:999px;
  box-shadow:0 2px 0 var(--pink);
  width:max-content;
}
.page-number{
  text-align:center;color:#c0607a;font-weight:700;
  font-size:10px;margin-top:10px;letter-spacing:2.5px;flex:none;
}
.page-number .ico{font-size:13px;color:var(--deep);margin:0 4px}

/* ---------- FRONT COVER ---------- */
.cover{
  position:absolute;
  top:0;left:50%;
  width:50%;height:100%;
  z-index:10;
  transform-origin:left center;
  transform-style:preserve-3d;
  transition:transform 1.8s var(--ease-open),visibility 0s;
}
.book.open .cover{
  transform:translateZ(-2px) rotateY(-180deg);
  pointer-events:none;
  visibility:hidden;
  transition:transform 1.8s var(--ease-open),visibility 0s linear 1.8s;
}

.cover-front,
.cover-back{
  position:absolute;
  inset:0;
  border-radius:26px;
  overflow:hidden;
  backface-visibility:hidden;
  -webkit-backface-visibility:hidden;
}

.cover-front{
  background-color:#fff4f5;
  background-image:
    radial-gradient(circle,rgba(212,96,124,.22) 2px,transparent 2.5px),
    linear-gradient(160deg,#fff 0%,#fde4e9 100%);
  background-size:20px 20px,100% 100%;
  border:3px solid #fff;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  text-align:center;
  box-shadow:0 0 0 6px var(--pink),0 0 0 10px #fff,0 26px 40px -16px rgba(126,18,48,.45);
}
.cover-front::before{
  content:"";position:absolute;inset:18px;
  border:3px double var(--rose);
  border-radius:20px;pointer-events:none;
}

/* washi tape holding the cover corners */
.cover-tape{
  position:absolute;z-index:4;
  width:110px;height:30px;
  background-color:rgba(244,170,185,.85);
  background-image:repeating-linear-gradient(45deg,transparent 0 8px,rgba(255,255,255,.55) 8px 13px);
  box-shadow:0 1px 3px rgba(126,18,48,.2);
}
.cover-tape.a{top:14px;left:-18px;transform:rotate(-32deg)}
.cover-tape.b{bottom:18px;right:-22px;transform:rotate(-32deg);background-color:rgba(201,92,118,.75);background-image:repeating-linear-gradient(45deg,transparent 0 8px,rgba(255,255,255,.55) 8px 13px)}

/* ribbon bow */
.bow{
  position:absolute;top:24px;left:26px;
  width:60px;height:44px;z-index:4;
  filter:drop-shadow(0 3px 0 rgba(126,18,48,.25));
}
.bow .loop{
  position:absolute;top:4px;width:28px;height:32px;
  background:var(--rose);
  border-radius:50% 50% 50% 50%/60% 60% 40% 40%;
}
.bow .loop.l{left:0;transform:rotate(-30deg)}
.bow .loop.r{right:0;transform:rotate(30deg)}
.bow .knot{
  position:absolute;left:21px;top:14px;width:18px;height:18px;border-radius:50%;
  background:var(--deep);
  border:3px solid #fff;
}

.cover-sticker{position:absolute;z-index:3;color:var(--deep);font-size:22px;animation:bob 4.5s ease-in-out infinite}
.cover-sticker.one{top:26%;right:13%;color:var(--rose)}
.cover-sticker.two{bottom:17%;left:13%;font-size:18px;color:var(--deep);animation-delay:1.2s}

.cover-subtitle{
  position:relative;z-index:2;
  display:inline-block;
  background:#fff;
  color:var(--berry);
  font-family:'Cormorant Garamond',serif;font-weight:700;font-size:13px;letter-spacing:3px;text-transform:uppercase;
  padding:6px 14px;border-radius:999px;
  box-shadow:0 2px 0 var(--pink);
}
.cover-title{
  position:relative;z-index:2;
  font-family:'Pinyon Script',cursive;font-weight:400;
  font-size:clamp(52px,6.2vw,80px);line-height:1;
  color:var(--deep);
  margin:16px 0 8px;
  text-shadow:0 3px 0 #fff,0 6px 0 rgba(212,96,124,.35);
}

/* cute wax seal sticker */
.wax{
  position:relative;z-index:3;
  width:108px;height:108px;border-radius:50%;
  background:radial-gradient(circle at 35% 30%,#e0476a,#b8264a 55%,#7e1230);
  box-shadow:0 10px 16px -4px rgba(90,10,30,.5),0 0 0 4px #fff,0 0 0 6px var(--pink);
  display:grid;place-items:center;
  color:#f9c3cf;
  --petal-line:#8a1a38;
  margin:16px 0 22px;
  animation:bob 3.6s ease-in-out infinite;
}
.wax .ico{font-size:50px;filter:drop-shadow(0 2px 0 rgba(126,18,48,.4))}

.open-btn{
  z-index:5;
  padding:12px 28px;
  font-size:15px;
}
.open-btn .ico{font-size:19px}

.cover-back{
  transform:rotateY(180deg);
  background-color:#fbdbe2;
  background-image:radial-gradient(circle,rgba(255,255,255,.7) 2px,transparent 2.5px);
  background-size:20px 20px;
  border:3px solid #fff;
  display:grid;place-items:center;
  color:var(--deep);
}
.cover-back .ico{font-size:70px;filter:drop-shadow(0 4px 0 rgba(255,255,255,.7))}

/* ---------- INSTRUCTION ---------- */
.instruction{
  position:absolute;
  bottom:-44px;left:50%;width:50%;
  text-align:center;
  font-weight:800;font-size:11px;color:#fff;letter-spacing:2px;
  text-shadow:0 2px 0 rgba(126,18,48,.35);
  transition:opacity .5s;
  animation:breathe 2.6s ease-in-out infinite;
}
.book.open .instruction{opacity:0;animation:none}
@keyframes breathe{
  0%,100%{opacity:.75}
  50%{opacity:1}
}

/* ---------- HEART BURSTS ---------- */
.burst{
  position:fixed;
  z-index:30;
  pointer-events:none;
  color:var(--deep);
  filter:drop-shadow(0 2px 0 rgba(255,255,255,.7));
  animation:rise2 1.4s var(--ease-bounce) forwards;
}
@keyframes rise2{
  0%{opacity:0;transform:translate(-50%,-50%) scale(.4)}
  15%{opacity:1}
  100%{opacity:0;transform:translate(calc(-50% + var(--dx)),calc(-50% + var(--dy))) scale(1.1) rotate(var(--r))}
}

/* ---------- FINAL HEART ---------- */
.final-heart{
  position:fixed;inset:0;z-index:20;
  display:none;align-items:center;justify-content:center;
  pointer-events:none;
}
.final-heart.active{display:flex}
.final-heart .ico{
  font-size:120px;color:var(--deep);
  filter:drop-shadow(0 6px 0 #fff);
  animation:pop 1.3s var(--ease-bounce) forwards;
}
@keyframes pop{
  0%{transform:scale(0);opacity:0}
  50%{transform:scale(1.25);opacity:1}
  100%{transform:scale(1);opacity:0}
}

/* ============ TABLET & SMALL DESKTOP ============ */
@media (max-width:900px){
  .scene{padding:28px 14px}
  .book{width:min(900px,96vw);height:clamp(470px,76svh,620px)}
  .page{padding:clamp(24px,4vw,44px) clamp(16px,3.8vw,36px)}
  .letter-heading{font-size:clamp(30px,4vw,40px)}
  .paragraph{font-size:clamp(19px,2.7vw,26px)}
  .sticker{width:32px;height:32px;padding:7px}
}

@media (min-width:601px) and (max-width:900px){
  .cover-title{font-size:clamp(48px,7.6vw,66px)}
  .wax{width:112px;height:112px}
  .wax .ico{font-size:54px}
  .open-btn{font-size:15px;padding:12px 28px}
  .open-btn .ico{font-size:19px}
  .cover-subtitle{font-size:13px}
  .cover-sticker{font-size:30px}
  .bow{transform:scale(1.25);transform-origin:top left}
  .instruction{font-size:13px}
  .float.f1{font-size:44px}.float.f2{font-size:34px}.float.f3{font-size:38px}.float.f4{font-size:46px}
}

/* ============ PHONES: one page at a time ============ */
@media (max-width:600px){
  .scene{padding:36px 10px 72px;min-height:100svh}

  .book,
  .book.open{
    transform:none;
    width:90vw;
    height:clamp(440px,calc(100svh - 150px),660px);
    min-height:0;
  }

  .pages{border-radius:24px}
  .left,
  .fold,
  .sticker.tr{display:none}

  .right{width:100%;border-radius:24px;padding:24px 16px}
  .right::before{inset:10px;border-radius:16px}

  .cover{left:0;width:100%;transform-origin:left center}
  .book.open .cover{
    transform:rotateY(-180deg);
    transition:transform 1.4s var(--ease-open),visibility 0s linear 1.4s;
  }
  .cover-front{padding:clamp(64px,11svh,78px) 18px 44px}
  .cover-front::before{inset:12px}
  .cover-tape.a{width:86px;height:24px;top:10px;left:-14px}
  .cover-tape.b{width:86px;height:24px;bottom:12px;right:-16px}
  .bow{top:26px;left:50%;transform:translateX(-50%) scale(1.15);transform-origin:top center}
  .cover-subtitle{font-size:12px;letter-spacing:2.5px;padding:7px 14px}
  .cover-title{font-size:clamp(40px,min(15vw,9svh),64px);margin:clamp(8px,2svh,14px) 0 8px}
  .wax{width:clamp(84px,min(33vw,17svh),124px);height:clamp(84px,min(33vw,17svh),124px);margin:clamp(12px,3svh,20px) 0 clamp(16px,4svh,28px)}
  .wax .ico{font-size:clamp(42px,min(16.5vw,8.5svh),62px)}
  .open-btn{padding:12px 28px;font-size:15px;margin-top:4px}
  .open-btn .ico{font-size:19px}
  .cover-sticker{font-size:30px}
  .cover-sticker.one{top:10%;right:11%}
  .cover-sticker.two{bottom:12%;left:11%}
  .float.f1{font-size:46px}.float.f2{font-size:34px}.float.f3{font-size:38px}.float.f4{font-size:48px}

  .instruction{left:0;width:100%;bottom:-34px;font-size:12px;letter-spacing:1.5px}

  .letter-heading{font-size:clamp(30px,8.5vw,38px);margin:0 0 8px}
  .paragraph-area{min-height:0;padding:8px 4px}
  .paragraph{font-size:clamp(20px,5.4vw,24px);line-height:1.6;overflow-wrap:anywhere}
  .navigation{margin-top:14px;gap:8px;flex-wrap:wrap}
  .nav-btn{padding:10px 15px;font-size:12px}
  .progress{margin-top:10px;font-size:10px;padding:5px 12px}
  .page-number{margin-top:10px;font-size:9px}
}

/* ============ VERY SMALL PHONES ============ */
@media (max-width:380px){
  .right{padding:20px 12px}
  .letter-heading{font-size:28px}
  .paragraph{font-size:18px}
  .nav-btn{padding:9px 11px;font-size:11px}
}

/* ============ SHORT SCREENS ============ */
@media (max-height:620px) and (min-width:601px){
  .scene{padding:18px}
  .book{height:88svh;min-height:390px}
  .page{padding-top:26px;padding-bottom:26px}
  .paragraph{font-size:clamp(19px,2.1vw,24px);line-height:1.5}
  .letter-heading{font-size:clamp(30px,3.4vw,38px);margin-bottom:4px}
  .navigation{margin-top:8px}
  .progress{margin-top:8px}
  .page-number{margin-top:6px}
}
@media (max-height:520px) and (max-width:600px){
  .book{height:460px;min-height:460px}
  .paragraph-area{min-height:140px}
}

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.01ms!important;
    animation-iteration-count:1!important;
    transition-duration:.01ms!important;
  }
}