/* STYLE.CSS */
#app { position: relative; min-height: 100dvh; overflow: hidden; }

#loading-screen { position: fixed; inset: 0; background: #0d0d14; display: flex; flex-direction: column; align-items: center; justify-content: center; z-index: 9999; transition: opacity 0.8s, visibility 0.8s; }
#loading-screen.hidden { opacity: 0; visibility: hidden; pointer-events: none; }
.loading-heart { font-size: 3rem; animation: heartbeat 1.2s ease-in-out infinite; }
@keyframes heartbeat { 0%,100%{transform:scale(1)} 14%{transform:scale(1.2)} 28%{transform:scale(1)} 42%{transform:scale(1.1)} }
.loading-text { margin-top: 1rem; font-family: var(--font-display); font-size: 1.25rem; color: rgba(249,168,212,0.8); letter-spacing: 0.1em; font-style: italic; }

/* COVER */
#cover-page { position: fixed; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; z-index: 500; overflow: hidden; transition: opacity 1.2s cubic-bezier(0.16,1,0.3,1), transform 1.2s cubic-bezier(0.16,1,0.3,1); }
#cover-page.exit { opacity: 0; transform: scale(1.05); pointer-events: none; }
#flythrough-layer { position: absolute; inset: 0; overflow: hidden; pointer-events: none; }
.cover-bg-overlay { position: absolute; inset: 0; pointer-events: none; z-index: 3; background: radial-gradient(ellipse at 50% 30%, rgba(192,132,252,0.10) 0%, transparent 55%), radial-gradient(ellipse at 80% 80%, rgba(249,168,212,0.07) 0%, transparent 50%); }
.cover-content { position: relative; z-index: 10; text-align: center; padding: 2rem; max-width: 700px; background: radial-gradient(ellipse at 50% 50%, rgba(13,13,20,0.78) 0%, rgba(13,13,20,0.30) 65%, transparent 100%); border-radius: 50%; }
.cover-eyebrow { font-family: var(--font-body); font-size: 0.75rem; letter-spacing: 0.3em; text-transform: uppercase; color: rgba(249,168,212,0.6); margin-bottom: 1rem; opacity: 0; animation: fadeSlideUp 1s cubic-bezier(0.16,1,0.3,1) 0.3s forwards; }
.cover-title { font-family: var(--font-display); font-size: clamp(3rem,0.5rem + 7vw,7.5rem); font-weight: 300; letter-spacing: -0.02em; line-height: 1.05; background: linear-gradient(135deg, #f0e8ff 0%, #f9a8d4 40%, #c084fc 100%); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; margin-bottom: 1rem; opacity: 0; animation: fadeSlideUp 1s cubic-bezier(0.16,1,0.3,1) 0.5s forwards; }
.cover-subtitle { font-family: var(--font-display); font-size: clamp(1.125rem,1rem + 0.75vw,1.5rem); font-style: italic; font-weight: 300; color: rgba(240,232,255,0.65); margin-bottom: 3rem; opacity: 0; animation: fadeSlideUp 1s cubic-bezier(0.16,1,0.3,1) 0.7s forwards; }
.cover-btn { display: inline-flex; align-items: center; gap: 0.75rem; padding: 1rem 2rem; border-radius: 9999px; background: rgba(249,168,212,0.12); border: 1px solid rgba(249,168,212,0.3); font-family: var(--font-body); font-size: 0.875rem; letter-spacing: 0.06em; color: rgba(249,168,212,0.9); backdrop-filter: blur(16px); transition: all 0.4s cubic-bezier(0.16,1,0.3,1); cursor: pointer; opacity: 0; animation: fadeSlideUp 1s cubic-bezier(0.16,1,0.3,1) 0.9s forwards; }
.cover-btn:hover { background: rgba(249,168,212,0.22); border-color: rgba(249,168,212,0.65); transform: translateY(-2px); box-shadow: 0 8px 32px rgba(249,168,212,0.22); }
/* .floating-word { position: absolute; font-family: var(--font-display); font-style: italic; pointer-events: none; user-select: none; z-index: 4; animation: wordFloat linear infinite; } */

.floating-word {
  position: absolute;
  font-family: var(--font-display);
  font-style: italic;
  pointer-events: none;
  user-select: none;
  /* z-index 4 = above flythrough layer (z:2) but below cover-content (z:10) */
  z-index: 4;
  white-space: nowrap;
  /* Stagger the twinkle animation; opacity + slow drift upward */
  animation: wordFloat linear infinite;
  will-change: transform, opacity;
}

@keyframes wordFloat {
  0%   { transform: translateY(0)     rotate(var(--word-rot, 0deg)); opacity: 0; }
  8%   { opacity: var(--word-opacity, 0.22); }
  50%  { opacity: var(--word-opacity, 0.22); }
  /* Twinkle: dip to 40% of max opacity mid-animation */
  55%  { opacity: calc(var(--word-opacity, 0.22) * 0.4); }
  65%  { opacity: var(--word-opacity, 0.22); }
  92%  { opacity: var(--word-opacity, 0.22); }
  100% { transform: translateY(-140px) rotate(var(--word-rot, 0deg)); opacity: 0; }
}

@keyframes wordFloat { 0%{transform:translateY(0) rotate(var(--word-rot,0deg));opacity:0} 10%,90%{opacity:var(--word-opacity,0.07)} 100%{transform:translateY(-120px) rotate(var(--word-rot,0deg));opacity:0} }

/* NAV DOTS */
#chapter-nav { position: fixed; top: 50%; right: 1.5rem; transform: translateY(-50%); z-index: 200; display: flex; flex-direction: column; gap: 0.75rem; opacity: 0; transition: opacity 0.5s; }
#chapter-nav.visible { opacity: 1; }
.nav-dot { width: 10px; height: 10px; border-radius: 9999px; border: 1.5px solid rgba(255,255,255,0.35); background: transparent; cursor: pointer; transition: all 0.3s; position: relative; }
.nav-dot:hover,.nav-dot.active { background: rgba(255,255,255,0.8); border-color: rgba(255,255,255,0.8); transform: scale(1.3); }
.nav-dot::before { content: attr(data-label); position: absolute; right: calc(100% + 0.75rem); top: 50%; transform: translateY(-50%); white-space: nowrap; font-family: var(--font-body); font-size: 0.75rem; color: rgba(255,255,255,0.6); opacity: 0; pointer-events: none; transition: opacity 0.2s; letter-spacing: 0.04em; }
.nav-dot:hover::before { opacity: 1; }

/* MUSIC PLAYER */
#music-player { position: fixed; bottom: 1.5rem; left: 1.5rem; z-index: 200; display: flex; align-items: center; gap: 0.75rem; padding: 0.5rem 1rem; border-radius: 9999px; background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.1); backdrop-filter: blur(20px); opacity: 0; transition: all 0.3s; }
#music-player.visible { opacity: 1; }
#music-player:hover { background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.2); }
.music-btn { width: 32px; height: 32px; border-radius: 9999px; display: flex; align-items: center; justify-content: center; font-size: 14px; color: rgba(255,255,255,0.8); transition: all 0.2s; }
.music-btn:hover { color: #fff; transform: scale(1.1); }
.music-visualizer { display: flex; align-items: flex-end; gap: 2px; height: 16px; }
.music-bar { width: 3px; border-radius: 2px; background: rgba(249,168,212,0.7); animation: musicBar 1s ease-in-out infinite; transform-origin: bottom; }
.music-bar:nth-child(1){animation-delay:0s;height:8px}.music-bar:nth-child(2){animation-delay:.15s;height:14px}.music-bar:nth-child(3){animation-delay:.3s;height:6px}.music-bar:nth-child(4){animation-delay:.45s;height:12px}
@keyframes musicBar{0%,100%{transform:scaleY(0.4)}50%{transform:scaleY(1)}}
.music-visualizer.paused .music-bar{animation-play-state:paused}
#volume-slider{-webkit-appearance:none;appearance:none;width:60px;height:3px;border-radius:2px;background:rgba(255,255,255,0.2);outline:none;cursor:pointer}
#volume-slider::-webkit-slider-thumb{-webkit-appearance:none;width:10px;height:10px;border-radius:50%;background:rgba(249,168,212,0.9);cursor:pointer}

/* PAGES */
#pages-container { position: relative; width: 100%; }
.chapter-page { position: relative; min-height: 100dvh; width: 100%; overflow: hidden; display: none; }
.chapter-page.active { display: block; }
.page-bg { position: absolute; inset: 0; z-index: 0; }
.page-bg-image { position: absolute; inset: 0; background-size: cover; background-position: center; filter: brightness(0.4) saturate(0.8); }
.page-bg-overlay { position: absolute; inset: 0; background: radial-gradient(ellipse at 30% 20%, rgba(255,255,255,0.04) 0%, transparent 60%); }

/* CHAPTER HEADER */
.chapter-header { position: relative; z-index: 10; padding: 3rem 2rem 1.5rem; text-align: center; max-width: 1200px; margin: 0 auto; }
.chapter-eyebrow { display: inline-flex; align-items: center; gap: 0.5rem; font-family: var(--font-body); font-size: 0.75rem; letter-spacing: 0.3em; text-transform: uppercase; color: rgba(255,255,255,0.4); margin-bottom: 1rem; }
.chapter-eyebrow span { display: inline-block; width: 24px; height: 1px; background: rgba(255,255,255,0.3); }
.chapter-title { font-family: var(--font-display); font-size: clamp(2.5rem,1rem + 4vw,5rem); font-weight: 400; line-height: 1.1; margin-bottom: 0.75rem; letter-spacing: -0.02em; }
.chapter-subtitle { font-family: var(--font-display); font-size: clamp(1.125rem,1rem + 0.75vw,1.5rem); font-style: italic; font-weight: 300; color: rgba(255,255,255,0.55); }

/* CANVAS */
.chapter-canvas { position: relative; z-index: 5; width: 100%; min-height: 600px; padding: 2rem; }

/* PHOTO ELEMENTS */
.photo-element { position: absolute; cursor: pointer; transition: transform 0.4s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.4s; user-select: none; }
.photo-element:hover { z-index: 100 !important; }
.photo-element.style-polaroid .photo-frame { background: #f8f4ef; padding: 0.5rem 0.5rem 2rem 0.5rem; border-radius: 3px; box-shadow: 0 6px 24px rgba(0,0,0,0.4), 0 2px 8px rgba(0,0,0,0.25); }
.photo-element.style-polaroid img { width: 100%; aspect-ratio: 1/1; object-fit: cover; display: block; border-radius: 2px; }
.photo-element.style-polaroid .photo-caption { padding: 0.5rem 0.25rem 0.25rem; font-family: 'Segoe UI',cursive,sans-serif; font-size: 0.75rem; color: #4a4540; text-align: center; line-height: 1.3; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.photo-element.style-rounded .photo-frame { border-radius: 1rem; overflow: hidden; box-shadow: 0 12px 40px rgba(0,0,0,0.45); }
.photo-element.style-rounded img,.photo-element.style-raw img { width: 100%; object-fit: cover; display: block; }
.photo-element.style-rounded .photo-caption,.photo-element.style-raw .photo-caption { margin-top: 0.5rem; font-size: 0.75rem; color: rgba(255,255,255,0.5); text-align: center; font-style: italic; }
.photo-element.style-raw img { border-radius: 0.5rem; }
.photo-element.has-border .photo-frame { border: 2px solid rgba(255,255,255,0.12); }
.photo-element.hover-lift:hover { transform: translateY(-8px) scale(1.02) rotate(var(--photo-rotation,0deg)) !important; }
.photo-element.hover-tilt:hover { transform: rotate(calc(var(--photo-rotation,0deg) + 3deg)) scale(1.03) !important; }
.photo-element.hover-zoom:hover { transform: scale(1.06) rotate(var(--photo-rotation,0deg)) !important; }
@keyframes photoFloat{0%,100%{transform:translateY(0) rotate(var(--photo-rotation,0deg))}50%{transform:translateY(-8px) rotate(var(--photo-rotation,0deg))}}
@keyframes photoPulse{0%,100%{transform:scale(1) rotate(var(--photo-rotation,0deg))}50%{transform:scale(1.02) rotate(var(--photo-rotation,0deg))}}
.photo-element.anim-float{animation:photoFloat 6s ease-in-out infinite}
.photo-element.anim-pulse{animation:photoPulse 5s ease-in-out infinite}

/* STICKERS */
.sticker-element{position:absolute;pointer-events:none;user-select:none;display:flex;align-items:center;justify-content:center;z-index:8}
@keyframes stickerFloat{0%,100%{transform:translateY(0) rotate(var(--sticker-rotation,0deg))}50%{transform:translateY(-10px) rotate(var(--sticker-rotation,0deg))}}
@keyframes stickerPulse{0%,100%{transform:scale(1) rotate(var(--sticker-rotation,0deg))}50%{transform:scale(1.12) rotate(var(--sticker-rotation,0deg))}}
@keyframes stickerWiggle{0%,100%{transform:rotate(var(--sticker-rotation,0deg))}25%{transform:rotate(calc(var(--sticker-rotation,0deg) + 8deg))}75%{transform:rotate(calc(var(--sticker-rotation,0deg) - 8deg))}}
@keyframes stickerBounce{0%,100%{transform:translateY(0) rotate(var(--sticker-rotation,0deg))}30%{transform:translateY(-14px) rotate(var(--sticker-rotation,0deg))}60%{transform:translateY(-7px) rotate(var(--sticker-rotation,0deg))}}
.sticker-element.anim-float{animation:stickerFloat 5s ease-in-out infinite}
.sticker-element.anim-pulse{animation:stickerPulse 4s ease-in-out infinite}
.sticker-element.anim-wiggle{animation:stickerWiggle 3s ease-in-out infinite}
.sticker-element.anim-bounce{animation:stickerBounce 2.5s ease-in-out infinite}

/* DECORATIONS */
.decoration-element{position:absolute;pointer-events:none;z-index:3}
.sparkle-cluster{position:relative;display:flex;align-items:center;justify-content:center}
.sparkle-star{position:absolute;animation:sparkleTwinkle ease-in-out infinite}
@keyframes sparkleTwinkle{0%,100%{opacity:0;transform:scale(0) rotate(0deg)}50%{opacity:1;transform:scale(1) rotate(180deg)}}

/* CHAPTER CONTENT */
.chapter-content{position:relative;z-index:10;max-width:640px;margin:0 auto;padding:2rem 2rem 1rem}
.chapter-note{background:rgba(255,255,255,0.04);border:1px solid rgba(255,255,255,0.08);border-radius:1.5rem;padding:2rem;backdrop-filter:blur(20px);margin-bottom:1.5rem;position:relative;overflow:hidden}
.chapter-note::before{content:'"';position:absolute;top:-20px;left:1.5rem;font-family:var(--font-display);font-size:8rem;color:rgba(192,132,252,0.12);line-height:1;pointer-events:none}
.chapter-note-text{font-family:var(--font-body);font-size:1rem;line-height:1.9;color:rgba(240,232,255,0.8);white-space:pre-line;position:relative;z-index:1}
.chapter-quote{text-align:center;padding:1.5rem 2rem;margin-bottom:1.5rem}
.chapter-quote-text{font-family:var(--font-display);font-size:clamp(1.5rem,1.2rem + 1.25vw,2.25rem);font-style:italic;font-weight:300;color:rgba(240,232,255,0.7);line-height:1.5;margin-bottom:0.75rem}
.chapter-quote-author{font-family:var(--font-body);font-size:0.875rem;color:rgba(255,255,255,0.35);letter-spacing:0.06em}

/* CHALLENGE */
.chapter-challenge{position:relative;z-index:20;padding:2rem 2rem 3rem}
.challenge-card{max-width:540px;margin:0 auto;background:rgba(15,10,30,0.7);border:1px solid rgba(192,132,252,0.2);border-radius:1.5rem;padding:2rem;backdrop-filter:blur(30px);box-shadow:0 20px 60px rgba(0,0,0,0.5),0 0 60px rgba(192,132,252,0.1)}
.challenge-icon{font-size:2.5rem;text-align:center;margin-bottom:1rem;animation:stickerPulse 3s ease-in-out infinite}
.challenge-title{font-family:var(--font-display);font-size:clamp(1.5rem,1.2rem + 1.25vw,2.25rem);font-style:italic;font-weight:400;color:rgba(240,232,255,0.9);text-align:center;margin-bottom:0.5rem}
.challenge-question{font-family:var(--font-body);font-size:1rem;color:rgba(255,255,255,0.6);text-align:center;line-height:1.7;margin-bottom:1.5rem}
.challenge-input-wrap{position:relative;margin-bottom:1rem}
.challenge-input{width:100%;padding:1rem 1.25rem;border-radius:9999px;border:1.5px solid rgba(192,132,252,0.25);background:rgba(255,255,255,0.05);color:rgba(240,232,255,0.9);font-family:var(--font-body);font-size:1rem;transition:all 0.3s;outline:none;text-align:center}
.challenge-input:focus{border-color:rgba(192,132,252,0.6);background:rgba(255,255,255,0.08);box-shadow:0 0 0 4px rgba(192,132,252,0.1)}
.challenge-input::placeholder{color:rgba(255,255,255,0.25)}
.challenge-options{display:flex;flex-direction:column;gap:0.5rem;margin-bottom:1rem}
.challenge-option{padding:0.75rem 1.25rem;border-radius:9999px;border:1.5px solid rgba(192,132,252,0.2);background:rgba(255,255,255,0.04);color:rgba(240,232,255,0.75);font-family:var(--font-body);font-size:0.875rem;transition:all 0.25s;cursor:pointer;text-align:center}
.challenge-option:hover{border-color:rgba(192,132,252,0.5);background:rgba(192,132,252,0.1);color:rgba(240,232,255,0.95);transform:translateY(-1px)}
.challenge-option.selected{border-color:rgba(249,168,212,0.6);background:rgba(249,168,212,0.12);color:rgba(249,168,212,0.95)}
.fill-blank-display{font-family:var(--font-display);font-size:clamp(1.5rem,1.2rem + 1.25vw,2.25rem);font-style:italic;color:rgba(240,232,255,0.8);text-align:center;margin-bottom:1rem;line-height:1.6}
.fill-blank-display .blank{display:inline-block;min-width:120px;border-bottom:2px solid rgba(192,132,252,0.5);padding:0 0.5rem;color:rgba(249,168,212,0.9);font-style:normal}
.yes-no-buttons{display:flex;gap:1rem;justify-content:center;margin-bottom:1rem}
.yn-btn{flex:1;max-width:140px;padding:1rem 1.5rem;border-radius:9999px;border:1.5px solid;font-family:var(--font-display);font-size:1.25rem;font-style:italic;cursor:pointer;transition:all 0.3s cubic-bezier(0.34,1.56,0.64,1)}
.yn-btn.yes{border-color:rgba(110,231,183,0.4);color:rgba(110,231,183,0.85);background:transparent}
.yn-btn.no{border-color:rgba(249,168,212,0.4);color:rgba(249,168,212,0.85);background:transparent}
.yn-btn:hover{transform:scale(1.05)}
.order-items{display:flex;flex-direction:column;gap:0.5rem;margin-bottom:1rem}
.order-item{display:flex;align-items:center;gap:0.75rem;padding:0.75rem 1rem;border-radius:0.75rem;border:1.5px solid rgba(255,255,255,0.1);background:rgba(255,255,255,0.04);cursor:grab;transition:all 0.2s;font-family:var(--font-body);font-size:0.875rem;color:rgba(240,232,255,0.8)}
.order-item:hover{background:rgba(255,255,255,0.07);border-color:rgba(255,255,255,0.2)}
.order-item.dragging{opacity:0.5;cursor:grabbing}
.find-heart-area{width:100%;height:200px;border-radius:1rem;background:rgba(255,255,255,0.03);border:1px solid rgba(255,255,255,0.08);position:relative;overflow:hidden;margin-bottom:1rem;cursor:crosshair}
.hidden-heart{position:absolute;font-size:1.5rem;opacity:0;pointer-events:all;cursor:pointer;transition:opacity 0.2s}
.find-heart-area:hover .hidden-heart{opacity:0.08}
.hidden-heart:hover{opacity:1 !important}
.challenge-submit{width:100%;padding:1rem 1.5rem;border-radius:9999px;background:linear-gradient(135deg,rgba(192,132,252,0.3),rgba(249,168,212,0.2));border:1.5px solid rgba(192,132,252,0.4);color:rgba(240,232,255,0.9);font-family:var(--font-body);font-size:0.875rem;letter-spacing:0.06em;transition:all 0.3s cubic-bezier(0.34,1.56,0.64,1);cursor:pointer}
.challenge-submit:hover{background:linear-gradient(135deg,rgba(192,132,252,0.5),rgba(249,168,212,0.35));border-color:rgba(192,132,252,0.7);transform:translateY(-2px);box-shadow:0 8px 24px rgba(192,132,252,0.25)}
.challenge-hint{margin-top:0.75rem;font-size:0.75rem;color:rgba(255,255,255,0.3);text-align:center;font-style:italic;cursor:pointer;transition:color 0.2s}
.challenge-hint:hover{color:rgba(255,255,255,0.55)}
.challenge-feedback{margin-top:1rem;padding:1rem 1.25rem;border-radius:1rem;text-align:center;font-family:var(--font-display);font-style:italic;font-size:1.25rem;display:none}
.challenge-feedback.success{display:block;color:rgba(110,231,183,0.9);background:rgba(110,231,183,0.08);border:1px solid rgba(110,231,183,0.2);animation:feedbackPop 0.5s cubic-bezier(0.34,1.56,0.64,1) forwards}
.challenge-feedback.fail{display:block;color:rgba(249,168,212,0.9);background:rgba(249,168,212,0.08);border:1px solid rgba(249,168,212,0.2);animation:feedbackPop 0.4s cubic-bezier(0.34,1.56,0.64,1) forwards}
@keyframes feedbackPop{0%{transform:scale(0.9);opacity:0}100%{transform:scale(1);opacity:1}}
.btn-next-chapter{width:100%;margin-top:1.25rem;padding:1rem 1.5rem;border-radius:9999px;background:linear-gradient(135deg,rgba(249,168,212,0.25),rgba(192,132,252,0.2));border:1.5px solid rgba(249,168,212,0.4);color:rgba(249,168,212,0.9);font-family:var(--font-display);font-size:1.25rem;font-style:italic;font-weight:400;letter-spacing:0.04em;cursor:pointer;transition:all 0.4s cubic-bezier(0.34,1.56,0.64,1);text-align:center;display:none}
.btn-next-chapter.visible{display:block;animation:fadeSlideUp 0.6s cubic-bezier(0.16,1,0.3,1) forwards}
.btn-next-chapter:hover{background:linear-gradient(135deg,rgba(249,168,212,0.4),rgba(192,132,252,0.3));border-color:rgba(249,168,212,0.7);transform:translateY(-2px);box-shadow:0 8px 30px rgba(249,168,212,0.25)}
.birthday-banner{text-align:center;padding:1.5rem 2rem;position:relative;z-index:15}
.birthday-banner-text{font-family:var(--font-display);font-size:clamp(2rem,1.2rem + 2.5vw,3.5rem);font-weight:300;letter-spacing:0.05em;background:linear-gradient(135deg,#f9a8d4,#c084fc,#f9a8d4);background-size:200% auto;-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;animation:textShimmer 3s linear infinite}
@keyframes textShimmer{0%{background-position:0% center}100%{background-position:200% center}}

/* TRANSITIONS */
#transition-overlay{position:fixed;inset:0;z-index:1000;pointer-events:none;display:flex;align-items:center;justify-content:center;overflow:hidden}
.transition-curtain{position:absolute;inset:0;background:radial-gradient(circle at center,#1a0533 0%,#0d0d14 100%);transform:scaleY(0);transform-origin:bottom}
.transition-center{position:relative;z-index:2;opacity:0;font-family:var(--font-display);font-size:1.25rem;font-style:italic;color:rgba(240,232,255,0.6);letter-spacing:0.1em}

/* PARTICLES / CONFETTI */
#particle-canvas{position:fixed;inset:0;pointer-events:none;z-index:1}
#confetti-canvas{position:fixed;inset:0;pointer-events:none;z-index:999}

/* LIGHTBOX */
#lightbox{position:fixed;inset:0;z-index:900;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,0.92);backdrop-filter:blur(20px);opacity:0;visibility:hidden;transition:opacity 0.4s,visibility 0.4s;cursor:pointer}
#lightbox.open{opacity:1;visibility:visible}
#lightbox img{max-width:90vw;max-height:90dvh;object-fit:contain;border-radius:0.75rem;box-shadow:0 12px 40px rgba(0,0,0,0.45);animation:lightboxIn 0.4s cubic-bezier(0.16,1,0.3,1);cursor:default}
@keyframes lightboxIn{from{transform:scale(0.9);opacity:0}to{transform:scale(1);opacity:1}}
.lightbox-caption{position:absolute;bottom:2rem;left:50%;transform:translateX(-50%);font-family:var(--font-display);font-style:italic;font-size:1.25rem;color:rgba(255,255,255,0.7);white-space:nowrap;pointer-events:none}
.lightbox-close{position:absolute;top:1.5rem;right:1.5rem;width:44px;height:44px;display:flex;align-items:center;justify-content:center;border-radius:9999px;background:rgba(255,255,255,0.1);border:1px solid rgba(255,255,255,0.15);color:rgba(255,255,255,0.7);font-size:1.25rem;cursor:pointer;transition:all 0.2s}
.lightbox-close:hover{background:rgba(255,255,255,0.18);color:#fff}

/* SCROLL INDICATOR */
.scroll-indicator{position:absolute;bottom:2rem;left:50%;transform:translateX(-50%);z-index:20;display:flex;flex-direction:column;align-items:center;gap:0.5rem;opacity:0.4;animation:scrollBounce 2s ease-in-out infinite}
@keyframes scrollBounce{0%,100%{transform:translateX(-50%) translateY(0);opacity:0.4}50%{transform:translateX(-50%) translateY(8px);opacity:0.7}}
.scroll-indicator span{font-size:0.75rem;letter-spacing:0.15em;text-transform:uppercase;color:rgba(255,255,255,0.5)}

/* SHARED */
@keyframes fadeSlideUp{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}
@keyframes fadeIn{from{opacity:0}to{opacity:1}}

/* RESPONSIVE */
@media(max-width:768px){
  .chapter-header{padding:2rem 1rem 1rem}
  .chapter-canvas{min-height:480px;padding:1rem}
  .chapter-content{padding:1rem 1rem}
  .chapter-challenge{padding:1rem 1rem 2rem}
  .photo-element{max-width:190px !important}
  #chapter-nav{right:0.75rem}
  #music-player{bottom:1rem;left:1rem}
  .challenge-card{padding:1.25rem}
  .cover-content{padding:1.25rem}
}
@media(max-width:480px){
  .photo-element{max-width:150px !important}
  .chapter-note{padding:1.25rem}
  .challenge-card{padding:1rem}
}