@import url("https://fonts.googleapis.com/css2?family=Dancing+Script:wght@400..700&display=swap");

:root {
  --envelope-x: clamp(230px, 80vw, 310px);
  --envelope-y: calc(var(--envelope-x) * 0.68);
  --envelope-bg: #fff5f8;
  --envelope-shadow: #f4b8c8;
  --ornament-size: 3.6rem;
  --heart-size: clamp(54px, 20vw, 80px);
  --flap-bottom: clamp(20px, 9vw, 34px);
  --letter-x: 210px;
  --letter-y: calc(210px - 1rem - 10px);
  --letter-bg: #fffafc;
  --letter-shadow: #f0c4d4;
  --letter-text: #5c2d42;
  --letter-font: "Dancing Script", serif;
  --letter-button-text: #d4567a;
  --heart-bg: #e84a7f;
  --heart-text: white;
}

@media (min-width: 768px) {
  :root {
    --envelope-x: clamp(380px, 58vw, 520px);
    --envelope-y: calc(var(--envelope-x) * 0.67);
    --ornament-size: 4.2rem;
    --heart-size: clamp(80px, 11vw, 108px);
    --flap-bottom: clamp(36px, 6vw, 60px);
  }
}

@media (min-width: 1200px) {
  :root {
    --envelope-x: clamp(400px, 36vw, 520px);
    --envelope-y: calc(var(--envelope-x) * 0.66);
    --ornament-size: 4.4rem;
    --heart-size: clamp(82px, 8vw, 112px);
    --flap-bottom: clamp(44px, 4.5vw, 68px);
  }
}
html {
  font-size: clamp(16px, 0.35vw + 14px, 20px);
}

#letter-birthday {
  position: fixed;
  inset: 0;
  z-index: 40;
  margin: 0;
  overflow: hidden;
  height: 100dvh;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.65s ease, visibility 0.65s ease;
}

#letter-birthday.is-active {
  z-index: 80;
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.cssletter {
  box-sizing: border-box;
  position: relative;
  width: 100%;
  height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  user-select: none;
  -webkit-user-select: none;
  margin: 0;
  overflow: hidden;
  padding: clamp(16px, 4vw, 36px);
}

.envelope {
  position: relative;
  width: var(--envelope-x);
  height: var(--envelope-y);
  background: var(--envelope-bg);
  box-shadow:
    inset 0 0 30px -5px var(--envelope-shadow),
    0 0 50vw 0 #f5c6d6;
  transition:
    background-color 0.55s ease,
    box-shadow 0.55s ease;
}

.envelope-flap {
  width: 100%;
  height: 71%;
  position: absolute;
  top: 0;
  z-index: 3;
  overflow: hidden;
  transition:
    transform 0.75s cubic-bezier(0.22, 0.8, 0.24, 1),
    opacity 0.45s ease;
  transform-origin: top;
  pointer-events: all;
}

.envelope-folds {
  width: 100%;
  height: 100%;
  overflow: hidden;
  z-index: 2;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  transition:
    opacity 0.45s ease,
    visibility 0s linear 0.45s;
}

.envelope-flap::before,
.envelope-left::before,
.envelope-right::before,
.envelope-bottom::before {
  content: "";
  transform: rotate(45deg);
  background: var(--envelope-bg);
  box-shadow: 0 0 30px -5px var(--envelope-shadow);
  width: 100%;
  aspect-ratio: 1;
  display: block;
  position: absolute;
  top: 60%;
}

.envelope-flap::before {
  border-radius: 5rem;
  bottom: var(--flap-bottom);
  border-radius: 5rem;
  top: auto;
}

.envelope-left::before {
  top: 10%;
  left: -65%;
}

.envelope-right::before {
  top: 10%;
  right: -65%;
}

.envelope-bottom::before {
  top: 60%;
  border-radius: 5rem;
}

.heart {
  z-index: 4;
  position: relative;
  box-shadow: none;
  border: none;
  width: var(--heart-size);
  aspect-ratio: 1;
  background:
    radial-gradient(circle at 60% 65%, var(--heart-bg) 64%, #0000 65%) top
      left/50% 50%,
    radial-gradient(circle at 40% 65%, var(--heart-bg) 64%, #0000 65%) top
      right/50% 50%,
    conic-gradient(from -45deg at 50% 85.5%, var(--heart-bg) 90deg, #0000 0)
      bottom/100% 50%;
  background-repeat: no-repeat;
  left: 50%;
  top: 70%;
  transform: translate(-50%, -50%);
  cursor: pointer;
  transition:
    opacity 0.35s ease,
    visibility 0s linear 0.35s;
}

.heart::before {
  content: "";
  display: block;
  position: absolute;
  width: var(--heart-size);
  aspect-ratio: 1;
  background:
    radial-gradient(circle at 60% 65%, #ffffff26 64%, #0000 65%) top left/50%
      50%,
    radial-gradient(circle at 40% 65%, #ffffff26 64%, #0000 65%) top right/50%
      50%,
    conic-gradient(from -45deg at 50% 85.5%, #ffffff26 90deg, #0000 0)
      bottom/100% 50%;
  background-repeat: no-repeat;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%) scale(0);
  transition: 0.3s ease all;
  z-index: -1;
}

.heart:hover,
.heart:active,
.heart:focus {
  transform: translate(-50%, -50%);
  background-color: transparent;
  color: var(--heart-text);
}

.heart:hover::before,
.heart:active::before,
.heart:focus::before {
  transform: translate(-50%, -50%) scale(0.8);
}

.heart-text {
  transform: translateY(-10px);
  display: block;
  color: var(--heart-text);
  font-size: clamp(1rem, 0.9rem + 1vw, 1.5rem);
  font-family: var(--letter-font);
}

.envelope.active * {
  pointer-events: none;
}

.envelope.active .envelope-flap {
  transform: rotateX(-180deg) translateY(0);
  perspective: 10px;
}

.envelope.active .envelope-flap::before {
  box-shadow: inset 0 0 30px -5px var(--envelope-shadow);
}

.envelope.active .heart {
  display: none;
}

.reveal-letter {
  box-sizing: border-box;
  font-family: var(--letter-font);
  color: #5c2d42;
  background-color: var(--letter-bg);
  background-image: repeating-linear-gradient(
    to bottom,
    #0000 0,
    #0000 28px,
    #e8a0b01a 29px,
    #0000 30px
  );
  background-attachment: local;
  box-shadow:
    inset 0 0 36px #f0a8c022,
    0 16px 30px -18px #d4567a44;
  border: 0;
  border-radius: 0;
  width: min(94vw, calc(var(--envelope-x) * 0.94));
  min-height: clamp(160px, 40vw, 220px);
  max-height: min(68vh, 460px);
  padding: clamp(1.05rem, 2.4vw, 1.5rem) clamp(1rem, 3vw, 1.4rem);
  text-align: center;
  position: absolute;
  left: 50%;
  top: 82%;
  overflow-y: auto;
  overflow-x: hidden;
  opacity: 0;
  transform: translate(-50%, -100%) scale(0.96);
  transition:
    opacity 0.35s ease,
    top 0.75s cubic-bezier(0.22, 0.8, 0.24, 1),
    transform 0.85s cubic-bezier(0.22, 0.8, 0.24, 1);
  pointer-events: none;
  z-index: 1;
  will-change: transform, top, opacity;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.reveal-letter::-webkit-scrollbar {
  display: none;
}

.reveal-letter::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(120% 50% at 50% 0%, #e84a7f18 0%, #0000 70%),
    radial-gradient(55% 120% at 0% 40%, #f4a8b814 0%, #0000 70%),
    radial-gradient(55% 120% at 100% 40%, #f4a8b814 0%, #0000 70%);
  mix-blend-mode: multiply;
  opacity: 0.7;
}

.reveal-letter .letter-title {
  margin: 0 0 clamp(0.45rem, 1.4vw, 0.75rem);
  padding: 0 0.15rem;
  font-size: clamp(1.4rem, 1.1rem + 1.4vw, 1.9rem);
  font-weight: 700;
  line-height: 1.25;
  color: #d4567a;
  text-wrap: balance;
  min-height: 1.25em;
}

.reveal-letter .letter-title[hidden] {
  display: none;
}

.reveal-letter .letter-body {
  margin: 0;
  padding: 0.25rem 0.15rem 0.65rem;
  font-size: clamp(1.08rem, 0.92rem + 0.85vw, 1.28rem);
  line-height: 1.55;
  letter-spacing: 0.01em;
  text-wrap: pretty;
  white-space: pre-wrap;
  text-align: justify;
}

.reveal-letter .letter-body:not(:empty)::first-letter {
  font-size: 1.8em;
  color: #d4567a;
  font-weight: 700;
}

.reveal-letter .letter-signature {
  display: block;
  margin-top: clamp(0.4rem, 1.2vw, 0.75rem);
  margin-left: auto;
  width: fit-content;
  max-width: 100%;
  font-size: clamp(1.18rem, 1rem + 0.9vw, 1.55rem);
  font-style: normal;
  color: #b84d6e;
  text-shadow: 0 1px 0 #fff5f8;
  text-align: right;
  min-height: 1.2em;
}

.reveal-letter .letter-signature[hidden] {
  display: none;
}

.reveal-letter .letter-continue {
  display: block;
  margin: clamp(0.85rem, 2vw, 1.25rem) auto 0;
  padding: 0.55rem 1.45rem;
  border: 1.5px solid #e84a7f;
  border-radius: 999px;
  background: linear-gradient(180deg, #ff7aa8 0%, #e84a7f 100%);
  color: #fff;
  font-family: var(--letter-font);
  font-size: clamp(1rem, 0.9rem + 0.45vw, 1.2rem);
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.55s ease,
    visibility 0s linear 0.55s,
    box-shadow 0.25s ease,
    filter 0.25s ease;
  box-shadow: 0 8px 18px -10px #e84a7f99;
  pointer-events: none;
}

.reveal-letter .letter-continue.is-visible {
  opacity: 1;
  visibility: visible;
  transition:
    opacity 0.55s ease,
    visibility 0s linear 0s,
    box-shadow 0.25s ease,
    filter 0.25s ease;
  pointer-events: auto;
}

.reveal-letter .letter-continue:hover,
.reveal-letter .letter-continue:focus-visible {
  filter: brightness(1.05);
  box-shadow: 0 10px 22px -10px #e84a7fcc;
  outline: none;
}

.reveal-letter .letter-continue:active {
  filter: brightness(0.97);
}

.reveal-letter .is-typing::after {
  content: "";
  display: inline-block;
  width: 0.08em;
  height: 1em;
  margin-left: 0.12em;
  vertical-align: -0.12em;
  background: #d4567a;
  animation: caret-blink 0.7s steps(1) infinite;
}

@keyframes caret-blink {
  0%,
  45% {
    opacity: 1;
  }
  50%,
  100% {
    opacity: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal-letter .is-typing::after {
    animation: none;
    opacity: 0;
  }
}

.envelope.active .reveal-letter {
  opacity: 1;
  z-index: 1;
}

.envelope.extracting .reveal-letter {
  transform: translate(-50%, -190%) scale(1);
}

.envelope.lowered {
  background: transparent;
  box-shadow: none;
}

.envelope.lowered .envelope-folds,
.envelope.lowered .heart {
  opacity: 0;
  visibility: hidden;
}

.envelope.lowered .envelope-flap {
  opacity: 0;
  visibility: hidden;
}

.envelope.lowered .reveal-letter {
  top: 50%;
  transform: translate(-50%, -50%) scale(1);
  opacity: 1;
  z-index: 6;
  pointer-events: auto;
}

.envelope.active .envelope-flap {
  z-index: 0;
}

@media (min-width: 768px) {
  .reveal-letter {
    width: min(92vw, calc(var(--envelope-x) * 0.94));
    min-height: clamp(280px, 36vw, 420px);
    max-height: min(78vh, 720px);
    padding: clamp(1.25rem, 2.4vw, 1.75rem) clamp(1.2rem, 3vw, 1.8rem);
  }

  .reveal-letter .letter-title {
    font-size: clamp(1.75rem, 1.35rem + 1.1vw, 2.25rem);
  }

  .reveal-letter .letter-body {
    font-size: clamp(1.28rem, 1.1rem + 0.7vw, 1.55rem);
    line-height: 1.6;
  }

  .reveal-letter .letter-signature {
    font-size: clamp(1.35rem, 1.15rem + 0.7vw, 1.7rem);
  }

  .reveal-letter .letter-continue {
    margin-top: clamp(1rem, 2.2vw, 1.4rem);
    padding: 0.65rem 1.7rem;
    font-size: clamp(1.1rem, 0.95rem + 0.5vw, 1.35rem);
  }
}

@media (min-width: 768px) and (max-width: 1199px) {
  .reveal-letter {
    min-height: clamp(300px, 40vh, 460px);
    max-height: min(80vh, 740px);
  }
}

.letter {
  box-sizing: border-box;
  font-family: var(--letter-font);
  font-size: 0.9rem;
  line-height: 1.1;
  background-color: var(--letter-bg);
  color: var(--letter-text);
  width: var(--letter-x);
  height: var(--letter-y);
  user-select: none;
  box-shadow: inset 0 0 20px -5px var(--letter-shadow);
  padding: 2.4rem 0.9rem 0.9rem;
  margin: 0;
  cursor: grab;
  position: absolute;
  top: 1rem;
  overflow: auto;
  text-align: center;
  border: 0;
}

.letter:active {
  cursor: grabbing;
}

.letter.center {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
}

.letter cite {
  font-size: 1.25rem;
  color: var(--letter-text);
  margin-top: 1rem;
}

.letter cite::before {
  content: none;
}

.letter:nth-child(even) {
  transform: skew(-2deg) translateY(-4px);
}

.letter:nth-child(odd) {
  transform: skew(2deg) translateY(4px);
}

@media (min-width: 650px) {
  .letter {
    font-size: 1.1rem;
  }
}

.closeLetter {
  font-size: 0 !important;
  position: absolute;
  top: 1rem;
  left: 50%;
  transform: translateX(-50%);
  background: none;
  box-shadow: none;
  padding: 0;
  border: 0;
}

.closeLetter::before {
  content: "˚ʚ❤︎ɞ˚";
  font-size: 1.5rem !important;
  font-family: var(--letter-font);
  color: var(--letter-button-text);
  text-align: center;
}

.closeLetter:hover,
.closeLetter:active,
.closeLetter:focus {
  background-color: transparent;
  color: var(--letter-text);
  transform: translateX(-50%);
  padding: 0;
  margin: 0;
}

.closeLetter:hover::before,
.closeLetter:active::before,
.closeLetter:focus::before {
  content: "xXx";
}

/* Attribution */
@import url("https://frills.dev/css/abstracts/_variables.css");
@import url("https://frills.dev/css/components/_logo.css");

:root {
  --bodybg: #fce4ec;
}

footer {
  position: fixed;
  bottom: 1rem;
  right: 1rem;
  z-index: 10000000;
}

footer svg {
  width: 100px;
}

@media (prefers-reduced-motion: reduce) {
  #letter-birthday,
  #image-birthday {
    transition: none;
  }
}