@import url('https://fonts.googleapis.com/css2?family=Caveat:wght@400;700&family=Kalam:wght@400;700&family=Long+Cang&family=Zhi+Mang+Xing&family=Noto+Sans+SC:wght@300;400;700&display=swap');

:root {
  --mori-green-light: #eaf2e8;
  --mori-green-theme: #7fb086;
  --mori-green-dark: #4f7355;
  --mori-beige: #fdfaf2;
  --mori-brown: #8d7a68;
  --mori-brown-dark: #5c4d3f;
  --paper-cream: #faf7f2;
  --shadow-notebook: 0 20px 50px rgba(0, 0, 0, 0.25), 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-card: 0 10px 25px rgba(0, 0, 0, 0.1), 0 3px 10px rgba(0, 0, 0, 0.05);
  
  --font-hand: 'Kalam', 'Long Cang', 'Zhi Mang Xing', cursive;
  --font-sans: 'Noto Sans SC', sans-serif;
}

/* Reset and Core Setup */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body, html {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: var(--font-sans);
  color: var(--mori-brown-dark);
  background-color: #e2ede0;
  user-select: none;
}

/* Background Image and Glass Overlay */
body {
  background-image: url('cat_bg.png');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

/* Global Watercolor Paper Grain Overlay */
.paper-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.11;
  background-image: url("paper_texture.jpg");
  background-repeat: repeat;
  mix-blend-mode: multiply;
}

/* 1. Landing Cover */
#landing-cover {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1000;
  background-image: url('cat_bg.png');
  background-size: cover;
  background-position: center;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 1.2s cubic-bezier(0.76, 0, 0.24, 1);
  overflow: hidden;
}

#landing-cover::before {
  content: '';
  position: absolute;
  top: 0; left: 0; width: 100%; height: 100%;
  background: rgba(234, 242, 232, 0.25);
  backdrop-filter: blur(4px);
}

.cover-glass {
  position: relative;
  z-index: 10;
  background: rgba(253, 250, 242, 0.82);
  backdrop-filter: blur(10px);
  border: 2px dashed var(--mori-green-theme);
  padding: 40px 60px;
  border-radius: 24px;
  text-align: center;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
  max-width: 90%;
  filter: url(#handdrawn);
}

.cover-title {
  font-family: 'Caveat', cursive;
  font-size: 4rem;
  color: var(--mori-green-dark);
  margin-bottom: 5px;
  text-shadow: 1px 1px 0px #fff;
}

.cover-subtitle {
  font-family: var(--font-hand);
  font-size: 2rem;
  color: var(--mori-brown);
  margin-bottom: 35px;
}

.open-btn {
  font-family: var(--font-hand);
  font-size: 1.8rem;
  background: var(--paper-cream);
  border: 2px solid var(--mori-green-theme);
  color: var(--mori-brown-dark);
  padding: 10px 40px;
  border-radius: 40px;
  cursor: pointer;
  box-shadow: 0 6px 15px rgba(127, 176, 134, 0.25);
  transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  outline: none;
}

.open-btn:hover {
  transform: translateY(-3px) scale(1.03);
  background: #fff;
  box-shadow: 0 10px 20px rgba(127, 176, 134, 0.35);
  border-color: var(--mori-green-dark);
}

.cover-hint {
  font-size: 0.95rem;
  color: #7f8c8d;
  margin-top: 20px;
  letter-spacing: 1px;
}

/* 2. Main App Layout */
.app-container {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: rgba(234, 242, 232, 0.15);
  backdrop-filter: blur(2px);
  position: relative;
  z-index: 10;
  padding: 15px 0;
}

/* Top Navigation Bar */
.top-navbar {
  width: 100%;
  display: flex;
  justify-content: center;
  padding: 0 20px;
  z-index: 50;
}

.nav-links {
  background: rgba(253, 250, 242, 0.9);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(127, 176, 134, 0.3);
  padding: 6px 20px;
  border-radius: 30px;
  display: flex;
  gap: 15px;
  align-items: center;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.nav-item {
  background: transparent;
  border: none;
  padding: 8px 18px;
  border-radius: 20px;
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--mori-brown);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.25s ease;
}

.nav-item:hover, .nav-item.active {
  background: var(--mori-green-light);
  color: var(--mori-green-dark);
}

/* Disc rotation on hover/playing */
.disc-icon {
  display: inline-block;
  transition: transform 0.5s ease;
}
.nav-item:hover .disc-icon {
  transform: rotate(45deg);
}

/* Scrapbook Main Wrapper */
.scrapbook-wrapper {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 10px 20px;
  max-height: calc(100vh - 170px);
}

/* Scrapbook Container (holds notebook + decorations) */
.scrapbook-container {
  position: relative;
  width: 57.14vw; /* 4/7 of screen width */
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* Notebook corner decorations */
.deco-item {
  position: absolute;
  pointer-events: none;
  z-index: 15;
  filter: drop-shadow(2px 4px 8px rgba(0,0,0,0.12));
  animation: float-micro 6s ease-in-out infinite alternate;
}

@keyframes float-micro {
  0% { transform: translateY(0) rotate(0deg); }
  100% { transform: translateY(-8px) rotate(3deg); }
}

.flower-top-left { left: -60px; top: -50px; animation-delay: 0s; }
.leaf-top-right { right: -50px; top: -40px; animation-delay: 1s; }
.leaf-bottom-left { left: -50px; bottom: -40px; animation-delay: 2s; }
.flower-bottom-right { right: -60px; bottom: -50px; animation-delay: 1.5s; }
.small-flower-left { left: -70px; top: 50%; animation-delay: 0.5s; }
.small-leaf-right { right: -60px; top: 45%; animation-delay: 2.5s; }

/* Notebook Cover (Outer edge) */
.notebook-cover {
  width: 100%;
  max-width: 100%;
  height: 80vh;
  max-height: 700px;
  background: linear-gradient(135deg, #7fb086 0%, #6e9f75 100%);
  border: 5px solid #628e69;
  border-radius: 24px;
  box-shadow: var(--shadow-notebook);
  display: flex;
  position: relative;
  padding: 15px;
  transition: transform 0.5s ease;
}

/* Book Central Spine Binding */
.notebook-spine {
  width: 24px;
  height: 100%;
  position: absolute;
  left: 50%;
  top: 0;
  transform: translateX(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  align-items: center;
  pointer-events: none;
  background: linear-gradient(to right, 
    rgba(0,0,0,0.18) 0%, 
    rgba(0,0,0,0.06) 30%, 
    rgba(255,255,255,0.15) 50%, 
    rgba(0,0,0,0.06) 70%, 
    rgba(0,0,0,0.18) 100%);
}

.ring {
  width: 14px;
  height: 35px;
  background: linear-gradient(135deg, #d3c7b7 0%, #a89f92 100%);
  border: 1px solid #7a6e60;
  border-radius: 7px;
  box-shadow: 2px 2px 5px rgba(0,0,0,0.2);
}

/* Notebook Pages */
.notebook-page {
  flex: 0 0 50%;
  width: 50%;
  min-width: 50%;
  max-width: 50%;
  height: 100%;
  background-color: var(--mori-beige);
  background-image: radial-gradient(#dfd6c8 1.5px, transparent 1.5px);
  background-size: 20px 20px;
  position: relative;
  overflow: hidden;
  padding: 30px;
  display: flex;
  flex-direction: column;
}

.page-left {
  border-radius: 12px 0 0 12px;
  box-shadow: inset -15px 0 25px rgba(0,0,0,0.06);
  border-right: 1px solid rgba(0,0,0,0.1);
}

.page-right {
  border-radius: 0 12px 12px 0;
  box-shadow: inset 15px 0 25px rgba(0,0,0,0.06);
  border-left: 1px solid rgba(0,0,0,0.1);
}

/* Spread content tabs switching */
.spread-content {
  display: none;
  width: 100%;
  height: 100%;
  opacity: 0;
  transform: scale(0.98);
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.spread-content.active {
  display: flex;
  flex-direction: column;
  opacity: 1;
  transform: scale(1);
}

/* Typography styles */
.handwritten-title {
  font-family: var(--font-hand);
  font-size: 2.1rem;
  color: var(--mori-green-dark);
  text-align: center;
  margin-bottom: 15px;
}

.handwritten-text {
  font-family: var(--font-hand);
  font-size: 1.35rem;
  line-height: 1.7;
  color: var(--mori-brown-dark);
}

/* 3. SPREAD 0: Cover / Instruction page styling */
.intro-card {
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.watercolor-illustration {
  width: 100%;
  height: 200px;
  display: flex;
  justify-content: center;
  margin: 15px 0;
}

.illustration-img {
  width: 260px;
  height: 100%;
  background-repeat: no-repeat;
  mix-blend-mode: multiply;
  opacity: 0.85;
}

.instructions-list {
  display: flex;
  flex-direction: column;
  gap: 15px;
  margin-top: 10px;
}

.instruction-step {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.step-num {
  width: 22px;
  height: 22px;
  background: var(--mori-green-theme);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 4px;
}

.instruction-step p {
  font-size: 1.15rem;
  line-height: 1.4;
  color: var(--mori-brown-dark);
}

/* 4. SPREAD 1: Collage Canvas */
.canvas-area {
  width: 100%;
  height: 100%;
  position: relative;
  overflow: hidden;
}

.canvas-hint {
  font-size: 0.75rem;
  color: #a39686;
  text-align: center;
  position: absolute;
  top: 5px;
  left: 0;
  width: 100%;
  pointer-events: none;
}

/* Polaroid Card */
.polaroid {
  width: 224px;
  background: #ffffff;
  padding: 12px 12px 24px 12px;
  box-shadow: var(--shadow-card);
  border-radius: 2px;
  border: 1px solid rgba(0,0,0,0.05);
  display: flex;
  flex-direction: column;
  align-items: center;
  z-index: 10;
  filter: url(#handdrawn);
}

.polaroid-img {
  width: 200px;
  height: 200px;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  border: 1px solid #e5d8c3;
  cursor: pointer;
  position: relative;
}

.polaroid-img::before {
  content: '📸 点击上传';
  position: absolute;
  top: 0; left: 0; width: 100%; height: 100%;
  background: rgba(255,255,255,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  color: var(--mori-brown);
  opacity: 0;
  transition: opacity 0.2s ease;
}

.polaroid-img:hover::before {
  opacity: 1;
}

.polaroid-caption {
  margin-top: 12px;
  font-size: 1.2rem;
  color: var(--mori-brown-dark);
  text-align: center;
  width: 100%;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  cursor: pointer;
}

/* Washi Tape styling */
.washi-tape {
  position: absolute;
  width: 90px;
  height: 25px;
  background: rgba(127, 176, 134, 0.45);
  border: 1px dashed rgba(255, 255, 255, 0.5);
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  z-index: 20;
  pointer-events: none;
}

.tape-top-left {
  left: -20px;
  top: -10px;
  transform: rotate(-30deg);
}

.tape-top-right {
  right: -20px;
  top: -10px;
  transform: rotate(30deg);
}

/* Paper notes */
.paper-note {
  width: 200px;
  padding: 15px;
  background-color: #faf3e0;
  border-left: 5px solid var(--mori-green-theme);
  box-shadow: var(--shadow-card);
  z-index: 8;
  filter: url(#handdrawn);
}

.note-pin {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 1.2rem;
}

.note-body {
  font-size: 1.15rem;
  line-height: 1.5;
  color: var(--mori-brown-dark);
  cursor: pointer;
}

/* 5. SPREAD 2: Postcards & Flipping letters */
.postcards-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
}

.letter-card {
  perspective: 1000px;
  width: 90%;
  height: 210px;
  margin: 10px 0;
  cursor: pointer;
}

.letter-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.8s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  transform-style: preserve-3d;
}

.letter-card.flipped .letter-inner {
  transform: rotateY(180deg);
}

.letter-front, .letter-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: 12px;
  box-shadow: var(--shadow-card);
  border: 1px solid rgba(127,176,134,0.2);
}

.letter-front {
  background-color: #f7ede2;
  background-image: radial-gradient(#d5cbb8 1px, transparent 1px);
  background-size: 15px 15px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.envelope-stamp {
  font-size: 2.2rem;
  margin-bottom: 10px;
}

.envelope-to {
  font-size: 1.4rem;
  color: var(--mori-brown-dark);
  margin-bottom: 15px;
}

.envelope-seal {
  background: var(--mori-green-theme);
  color: white;
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: bold;
}

.letter-back {
  background-color: #faf8f5;
  transform: rotateY(180deg);
  padding: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.letter-paper {
  font-size: 1.15rem;
  line-height: 1.6;
  color: var(--mori-brown-dark);
}

/* 6. SPREAD 3: Accordion Timeline & Tree Guestbook */
.section-intro {
  font-size: 0.85rem;
  color: #7f8c8d;
  margin-bottom: 12px;
}

.accordion-timeline {
  display: flex;
  flex-direction: column;
  gap: 10px;
  overflow-y: auto;
  flex: 1;
}

.fold-card {
  background: var(--paper-cream);
  border-left: 4px solid var(--mori-green-theme);
  border-radius: 4px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  cursor: pointer;
  overflow: hidden;
  transition: all 0.3s ease;
}

.fold-header {
  padding: 12px 15px;
  background: rgba(127,176,134,0.08);
}

.fold-tag {
  font-weight: 700;
  color: var(--mori-green-dark);
  font-size: 0.95rem;
}

.fold-content {
  padding: 0 15px;
  max-height: 0;
  opacity: 0;
  transition: all 0.35s cubic-bezier(0.19, 1, 0.22, 1);
  font-size: 1.15rem;
  line-height: 1.5;
  color: var(--mori-brown-dark);
}

.fold-card.active {
  box-shadow: var(--shadow-card);
}

.fold-card.active .fold-content {
  padding: 12px 15px;
  max-height: 150px;
  opacity: 1;
}

/* Stump Guestbook */
.guestbook-area {
  display: flex;
  flex-direction: column;
  height: 100%;
  justify-content: space-between;
}

.tree-stump-board {
  position: relative;
  flex: 1;
  background: radial-gradient(circle, #dfc0a2 10%, #ce9f72 40%, #b88657 70%, #996e47 100%);
  border: 8px solid #7a502c;
  border-radius: 50%;
  box-shadow: inset 0 0 30px rgba(0,0,0,0.3), 0 8px 15px rgba(0,0,0,0.15);
  margin-bottom: 15px;
  overflow: hidden;
  max-height: 260px;
}

.board-title {
  position: absolute;
  top: 10px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(253, 250, 242, 0.9);
  padding: 4px 14px;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--mori-brown-dark);
  border: 1px dashed var(--mori-brown);
  z-index: 5;
}

.leaf-note {
  position: absolute;
  padding: 6px 12px;
  background-color: #aed6f1; /* default color, can be random leaf colors */
  border-radius: 12px 2px 12px 2px; /* leaf shape */
  font-size: 1rem;
  color: var(--mori-brown-dark);
  box-shadow: 2px 2px 6px rgba(0,0,0,0.15);
  cursor: grab;
  z-index: 10;
  filter: url(#handdrawn);
}

.static-leaf {
  background-color: #d4efdf;
}

.guestbook-form {
  display: flex;
  gap: 10px;
  background: rgba(253, 250, 242, 0.85);
  padding: 8px;
  border-radius: 20px;
  border: 1px dashed var(--mori-green-theme);
}

#wish-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-size: 1.15rem;
  padding: 0 10px;
  color: var(--mori-brown-dark);
}

#wish-submit-btn {
  background: var(--mori-green-theme);
  color: white;
  border: none;
  outline: none;
  padding: 6px 18px;
  border-radius: 15px;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.2s;
}

#wish-submit-btn:hover {
  background: var(--mori-green-dark);
}

/* 7. Bottom page turn controls */
.bottom-footer {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 30px;
  margin-top: 10px;
}

.chapter-title {
  font-size: 1.35rem;
  color: var(--mori-brown-dark);
  background: rgba(253, 250, 242, 0.75);
  padding: 4px 15px;
  border-radius: 15px;
}

.page-controls {
  display: flex;
  align-items: center;
  gap: 15px;
  background: rgba(253, 250, 242, 0.9);
  padding: 5px 15px;
  border-radius: 25px;
  border: 1px solid rgba(127,176,134,0.2);
  box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}

.control-btn {
  background: transparent;
  border: none;
  outline: none;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--mori-brown);
  cursor: pointer;
  transition: color 0.2s;
}

.control-btn:hover {
  color: var(--mori-green-dark);
}

.page-indicator {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--mori-brown);
}

/* 8. STICKER PREVIEWS & CROP */
.sticker-drawer-container {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%) translateY(calc(100% - 40px));
  width: 90%;
  max-width: 800px;
  background: rgba(253, 250, 242, 0.95);
  backdrop-filter: blur(10px);
  border: 2px solid var(--mori-green-theme);
  border-bottom: none;
  border-radius: 16px 16px 0 0;
  box-shadow: 0 -10px 30px rgba(0,0,0,0.1);
  z-index: 500;
  transition: transform 0.5s cubic-bezier(0.77, 0, 0.175, 1);
}

.sticker-drawer-container.open {
  transform: translateX(-50%) translateY(0);
}

.drawer-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 20px;
  border-bottom: 1px dashed rgba(127, 176, 134, 0.3);
  cursor: pointer;
}

.drawer-title {
  font-weight: 700;
  color: var(--mori-brown-dark);
  font-size: 0.9rem;
}

.toggle-drawer-btn {
  background: var(--mori-green-theme);
  color: white;
  border: none;
  outline: none;
  padding: 3px 12px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 700;
  cursor: pointer;
}

.stickers-grid {
  display: flex;
  gap: 20px;
  padding: 15px 25px;
  overflow-x: auto;
  align-items: center;
  height: 130px;
}

.sticker-item {
  flex-shrink: 0;
  cursor: grab;
  transition: transform 0.2s;
}

.sticker-item:hover {
  transform: scale(1.1);
}

/* Placed sticker on canvas styling */
.placed-sticker {
  position: absolute;
  z-index: 15;
  transform-origin: center center;
  cursor: grab;
}

/* Placed sticker active control outline */
.placed-sticker.selected, .draggable.selected {
  outline: 2px dashed var(--mori-green-theme);
}

/* Interactive control handles for placed stickers */
.sticker-control {
  position: absolute;
  width: 20px;
  height: 20px;
  background: white;
  border: 1.5px solid var(--mori-green-theme);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 9px;
  font-weight: bold;
  color: var(--mori-green-dark);
  cursor: pointer;
  z-index: 25;
  user-select: none;
  display: none; /* Hidden unless selected */
}

.placed-sticker.selected .sticker-control, .draggable.selected .sticker-control {
  display: flex;
}

.ctrl-delete {
  top: -10px;
  right: -10px;
  background: #fadbd8;
  border-color: #e74c3c;
  color: #c0392b;
}

.ctrl-rotate {
  bottom: -10px;
  left: -10px;
  cursor: ew-resize;
}

.ctrl-scale {
  bottom: -10px;
  right: -10px;
  cursor: nwse-resize;
}

/* Actual Preview/Placed backgrounds matching crop coordinates on stickers.jpg */
.sticker-preview {
  background-image: url('stickers.jpg');
  background-repeat: no-repeat;
  mix-blend-mode: multiply;
  transform-origin: center center;
  pointer-events: none;
}

.sticker-bear {
  width: 90px; height: 90px;
  background-size: 531px auto; /* Scale coordinates proportionally */
  background-position: -380px -415px;
}

.sticker-squirrel {
  width: 83px; height: 90px;
  background-size: 531px auto;
  background-position: -69px -415px;
}

.sticker-rabbit {
  width: 69px; height: 90px;
  background-size: 531px auto;
  background-position: -166px -415px;
}

.sticker-hedgehog {
  width: 97px; height: 90px;
  background-size: 531px auto;
  background-position: -242px -415px;
}

.sticker-fox {
  width: 138px; height: 90px;
  background-size: 531px auto;
  background-position: -173px -325px;
}

.sticker-cabin {
  width: 104px; height: 90px;
  background-size: 531px auto;
  background-position: -332px -325px;
}

.sticker-basket {
  width: 83px; height: 90px;
  background-size: 531px auto;
  background-position: -69px -325px;
}

.sticker-large-squirrel {
  width: 100px; height: 118px;
  background-size: 320px auto;
  background-position: 0px -231px;
}

/* 9. Live editing popup input */
.live-editor-textarea {
  font-family: var(--font-hand);
  font-size: 1.25rem;
  line-height: 1.6;
  color: var(--mori-brown-dark);
  background: #faf4e8;
  border: 1px dashed var(--mori-green-theme);
  width: 100%;
  height: 100%;
  resize: none;
  outline: none;
  box-sizing: border-box;
}

/* 10. Add Timeline Event Button */
.add-fold-btn {
  display: block;
  width: 100%;
  margin-top: 8px;
  padding: 8px 0;
  background: transparent;
  border: 2px dashed var(--mori-green-theme);
  border-radius: 8px;
  font-family: var(--font-hand);
  font-size: 1.2rem;
  color: var(--mori-green-theme);
  cursor: pointer;
  transition: all 0.25s ease;
  outline: none;
}

.add-fold-btn:hover {
  background: var(--mori-green-light);
  color: var(--mori-green-dark);
  border-color: var(--mori-green-dark);
}

/* 11. Responsive Mobile adjustments */
@media (max-width: 768px) {

  /* === Overall Layout: 20vh / 60vh / 20vh === */
  .app-container {
    padding: 0;
    height: 100vh;
    height: 100dvh;
  }

  .top-navbar {
    height: 18vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 5px;
  }

  .nav-links {
    gap: 8px;
    padding: 6px 12px;
    border-radius: 25px;
  }

  .nav-item {
    padding: 6px;
    font-size: 1.1rem;
  }

  .nav-item .nav-text {
    display: none; /* Hide text, only show icons on mobile */
  }

  /* === Scrapbook Area: Middle 60vh === */
  .scrapbook-wrapper {
    flex: none;
    height: 60vh;
    height: 60dvh;
    max-height: 60vh;
    padding: 0 2px;
    overflow: hidden;
  }

  /* === Notebook: Left-Right Layout, Full Width === */
  .notebook-cover {
    flex-direction: row; /* Keep left-right dual pages! */
    width: 100%;
    height: 100%;
    max-height: none;
    padding: 6px;
    border-radius: 8px;
    border-left: 3px solid #628e69;
    border-right: 3px solid #628e69;
  }

  .scrapbook-container {
    width: 100%;
  }

  /* Hide side decorations on mobile */
  .deco-item {
    display: none;
  }

  /* Spine stays vertical on mobile */
  .notebook-spine {
    width: 16px;
    height: 100%;
    left: 50%;
    top: 0;
    transform: translateX(-50%);
    flex-direction: column;
  }

  .ring {
    width: 10px;
    height: 22px;
  }

  /* Pages: Each 50% width, full height */
  .notebook-page {
    flex: 0 0 50%;
    width: 50%;
    min-width: 50%;
    max-width: 50%;
    height: 100%;
    padding: 10px;
    overflow-y: auto;
  }

  .page-left {
    border-radius: 6px 0 0 6px;
    border-right: 1px solid rgba(0,0,0,0.08);
    border-bottom: none;
    padding-bottom: 10px;
  }

  .page-right {
    border-radius: 0 6px 6px 0;
    border-left: 1px solid rgba(0,0,0,0.08);
    border-top: none;
    padding-top: 10px;
  }

  /* === Footer: Bottom 20vh === */
  .bottom-footer {
    height: 18vh;
    display: flex;
    align-items: center;
    padding: 0 10px;
    margin-top: 0;
  }

  .chapter-title {
    font-size: 0.9rem;
    padding: 3px 8px;
  }

  .page-controls {
    padding: 4px 10px;
    gap: 8px;
  }

  .control-btn {
    font-size: 0.75rem;
  }

  .page-indicator {
    font-size: 0.75rem;
  }

  /* === Content Scaling for Small Pages === */
  .intro-card {
    height: auto;
    justify-content: flex-start;
  }

  .watercolor-illustration {
    height: 60px;
    margin: 3px 0;
  }

  .illustration-img {
    width: 80px;
    height: 100%;
  }

  .handwritten-title {
    font-size: 1rem;
    margin-bottom: 5px;
  }

  .handwritten-text {
    font-size: 0.75rem;
    line-height: 1.4;
  }

  .handwritten {
    font-size: 0.75rem;
  }

  .instructions-list {
    gap: 5px;
    margin-top: 3px;
  }

  .instruction-step p {
    font-size: 0.65rem;
    line-height: 1.3;
  }

  .step-num {
    width: 14px;
    height: 14px;
    font-size: 0.55rem;
    margin-top: 1px;
  }

  .open-btn {
    font-size: 0.9rem;
    padding: 4px 15px;
    margin: 8px auto 0 auto !important;
  }

  .canvas-hint {
    font-size: 0.55rem;
  }

  /* Polaroid & Notes: Smaller for half-width pages */
  .polaroid {
    width: 90px;
    padding: 4px 4px 8px 4px;
  }

  .polaroid-img {
    width: 80px;
    height: 80px;
  }

  .polaroid-caption {
    font-size: 0.6rem;
    margin-top: 3px;
  }

  .washi-tape {
    width: 50px;
    height: 14px;
  }

  .paper-note {
    width: 100px;
    padding: 6px;
  }

  .note-body {
    font-size: 0.65rem;
    line-height: 1.3;
  }

  .note-pin {
    font-size: 0.8rem;
    top: -8px;
  }

  /* Letters: Smaller */
  .letter-card {
    height: 140px;
  }

  .envelope-stamp {
    font-size: 1.4rem;
    margin-bottom: 4px;
  }

  .envelope-to {
    font-size: 0.85rem;
    margin-bottom: 6px;
  }

  .envelope-seal {
    font-size: 0.6rem;
    padding: 3px 10px;
  }

  .letter-paper {
    font-size: 0.65rem;
    line-height: 1.3;
  }

  /* Timeline Folds: Compact */
  .fold-header {
    padding: 6px 8px;
  }

  .fold-tag {
    font-size: 0.7rem;
  }

  .fold-content {
    font-size: 0.7rem;
    line-height: 1.3;
  }

  .fold-card.active .fold-content {
    padding: 6px 8px;
    max-height: 100px;
  }

  .add-fold-btn {
    font-size: 0.8rem;
    padding: 4px 0;
    margin-top: 4px;
  }

  /* Guestbook: Compact */
  .tree-stump-board {
    max-height: 130px;
    border-width: 4px;
    margin-bottom: 5px;
  }

  .board-title {
    font-size: 0.6rem;
    padding: 2px 8px;
    top: 4px;
  }

  .leaf-note {
    font-size: 0.6rem;
    padding: 3px 6px;
  }

  .guestbook-form {
    padding: 4px;
    gap: 4px;
  }

  #wish-input {
    font-size: 0.75rem;
    padding: 0 5px;
  }

  #wish-submit-btn {
    font-size: 0.6rem;
    padding: 3px 8px;
  }

  .section-intro {
    font-size: 0.6rem;
    margin-bottom: 4px;
  }

  /* Sticker Drawer: Compact */
  .sticker-drawer-container {
    width: 95%;
  }

  .stickers-grid {
    height: 80px;
    padding: 6px 10px;
    gap: 10px;
  }

  .drawer-title {
    font-size: 0.65rem;
  }

  .sticker-control {
    width: 14px;
    height: 14px;
    font-size: 7px;
  }

  .ctrl-delete { top: -7px; right: -7px; }
  .ctrl-rotate { bottom: -7px; left: -7px; }
  .ctrl-scale { bottom: -7px; right: -7px; }
}