/* ==========================================================================
   LETTER — message in a bottle reveal
   ========================================================================== */

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

.letter__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
}

.letter__bottle-stage {
  position: relative;
  width: 220px;
  height: 280px;
  margin: var(--sp-6) auto 0;
  cursor: pointer;
}

.letter__bottle-glow {
  position: absolute;
  inset: -20%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(62, 198, 224, 0.22), transparent 70%);
  filter: blur(20px);
  animation: bottleGlowPulse 3.6s var(--ease-in-out) infinite;
  pointer-events: none;
}

@keyframes bottleGlowPulse {
  0%, 100% { opacity: 0.55; transform: scale(0.94); }
  50% { opacity: 1; transform: scale(1.04); }
}

.bottle {
  position: relative;
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 10px 35px rgba(62,198,224,0.25));
  animation: bottleBob 4.5s var(--ease-in-out) infinite;
  transition: filter 0.4s var(--ease-out);
}

@keyframes bottleBob {
  0%, 100% { transform: translateY(0) rotate(-2deg); }
  50% { transform: translateY(-14px) rotate(2deg); }
}

.letter__bottle-stage:hover .bottle,
.letter__bottle-stage:focus-visible .bottle {
  filter: drop-shadow(0 16px 48px rgba(62,198,224,0.5));
}
.letter__bottle-stage:focus-visible { outline: none; }

.letter__hint {
  margin-top: var(--sp-4);
  font-family: var(--font-mono);
  font-size: var(--fs-caption);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--c-foam-faint);
  display: flex;
  align-items: center;
  justify-content: center;
  white-space: nowrap;
  gap: var(--sp-2);
}

.letter__hint svg {
  flex-shrink: 0;
  width: 14px;
  height: 14px;
  animation: hintBounce 1.8s var(--ease-in-out) infinite;
}

@keyframes hintBounce {
  0%, 100% { transform: translateY(0); opacity: 0.7; }
  50% { transform: translateY(3px); opacity: 1; }
}

.letter__bottle-stage.is-opened { display: none; }

/* Envelope / unrolled letter panel */
.letter__panel {
  width: 100%;
  margin-top: var(--sp-6);
  background: linear-gradient(160deg, rgba(244,249,255,0.05), var(--c-panel));
  border: 1px solid var(--c-panel-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-6) var(--sp-6);
  backdrop-filter: var(--panel-blur);
  -webkit-backdrop-filter: var(--panel-blur);
  box-shadow: var(--shadow-panel);
  opacity: 0;
  max-height: 0;
  overflow: hidden;
  transform: translateY(20px);
  transition: opacity 1s var(--ease-out), transform 1s var(--ease-out),
              max-height 1s var(--ease-out), padding 1s var(--ease-out), margin 1s var(--ease-out);
}

.letter__panel.is-open {
  opacity: 1;
  max-height: 30000px;
  transform: translateY(0);
}

.letter__salutation {
  font-family: var(--font-display);
  font-size: var(--fs-display-md);
  color: var(--c-bio-gold);
  font-style: italic;
  letter-spacing: -0.01em;
}

.letter__body {
  margin-top: var(--sp-4);
  text-align: left;
  font-size: var(--fs-body-lg);
  line-height: var(--lh-relaxed);
  color: var(--c-foam-dim);
  overflow-wrap: break-word;
  word-wrap: break-word;
  word-break: break-word;
}

.letter__body p { margin-bottom: var(--sp-4); }
.letter__body p:last-child { margin-bottom: 0; }

/* Typewriter caret */
.letter__caret {
  display: inline-block;
  width: 2px;
  height: 1.1em;
  background: var(--c-bio-cyan);
  vertical-align: text-bottom;
  margin-left: 2px;
  animation: caretBlink 1s steps(1) infinite;
}

@keyframes caretBlink { 50% { opacity: 0; } }

.letter__signature {
  margin-top: var(--sp-5);
  padding-top: var(--sp-4);
  border-top: 1px solid var(--c-line);
  text-align: right;
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.25rem;
  color: var(--c-foam);
}

@media (max-width: 600px) {
  .letter__panel { padding: var(--sp-5) var(--sp-4); }
  .letter__bottle-stage { width: 170px; height: 220px; }
}