:root {
  --cloud-dancer: #F0EEE9;
  --cloud-dancer-dark: #E2E0DB;
  --slate: #2C3E50;
  --slate-light: #526D89;
  --amber: #E67E22;
  --amber-hover: #D67118;
  --white-glass: rgba(255, 255, 255, 0.65);
  --white-glass-hover: rgba(255, 255, 255, 0.85);
  --border-glass: rgba(255, 255, 255, 0.5);
  --shadow-sm: 0 4px 15px rgba(44, 62, 80, 0.05);
  --shadow-md: 0 10px 30px rgba(44, 62, 80, 0.1);
  --radius: 20px;
}

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

body {
  background-color: var(--cloud-dancer);
  color: var(--slate);
  font-family: 'Noto Sans KR', sans-serif;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem;
  background-image: 
    radial-gradient(at 0% 0%, rgba(255,255,255,0.8) 0px, transparent 50%),
    radial-gradient(at 100% 0%, rgba(230, 126, 34, 0.05) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(255,255,255,0.8) 0px, transparent 50%);
  background-attachment: fixed;
}

.container {
  width: 100%;
  max-width: 900px;
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

header {
  text-align: center;
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

header p {
  color: var(--slate-light);
  font-size: 1.1rem;
}

.dropzone {
  border: 2px dashed rgba(44, 62, 80, 0.2);
  border-radius: var(--radius);
  background: var(--white-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.dropzone.dragover {
  border-color: var(--amber);
  background: var(--white-glass-hover);
  transform: scale(1.02);
}

.dropzone-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem;
  text-align: center;
  pointer-events: none;
}

.dropzone-content svg {
  color: var(--slate-light);
  margin-bottom: 1rem;
  transition: color 0.3s ease;
}

.dropzone.dragover .dropzone-content svg {
  color: var(--amber);
}

.dropzone-content h2 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.dropzone-content p {
  color: var(--slate-light);
  font-size: 0.95rem;
}

.result-section {
  background: var(--white-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: relative;
  overflow: hidden;
}

.hidden {
  display: none !important;
}

.file-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid rgba(44, 62, 80, 0.1);
}

.file-name {
  font-weight: 600;
  font-size: 1.1rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 80%;
}

.badge {
  background: var(--cloud-dancer-dark);
  color: var(--slate);
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
}

.status-banner {
  padding: 1rem;
  background: rgba(230, 126, 34, 0.1);
  border-radius: 12px;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--slate);
  font-weight: 500;
}

.status-banner.success { background: rgba(46, 204, 113, 0.1); }
.status-banner.error { background: rgba(231, 76, 60, 0.1); }

.toc-container {
  background: rgba(255, 255, 255, 0.5);
  border-radius: 12px;
  padding: 1.5rem;
  max-height: 400px;
  overflow-y: auto;
}

.toc-container h3 {
  font-size: 1.1rem;
  margin-bottom: 1rem;
  color: var(--slate);
}

.toc-tree {
  list-style: none;
  font-size: 0.95rem;
}

.toc-tree li {
  padding: 0.5rem 0;
  border-bottom: 1px dashed rgba(44, 62, 80, 0.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.toc-tree li:last-child { border-bottom: none; }

.toc-label {
  display: flex;
  align-items: center;
  flex: 1;
  cursor: pointer;
  gap: 0.75rem;
  padding: 0.25rem 0;
}

.toc-checkbox {
  appearance: none;
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border: 2px solid var(--slate-light);
  border-radius: 6px;
  background-color: var(--cloud-dancer);
  cursor: pointer;
  position: relative;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  flex-shrink: 0;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.toc-checkbox:hover {
  border-color: var(--amber);
  transform: scale(1.05);
}

.toc-checkbox:checked {
  background-color: var(--amber);
  border-color: var(--amber);
}

.toc-checkbox:checked::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 6px;
  width: 4px;
  height: 9px;
  border: solid white;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

.toc-title { 
  flex: 1; 
  margin-right: 1rem; 
  font-weight: 500;
  transition: color 0.2s;
}

.toc-label:hover .toc-title {
  color: var(--amber);
}
.toc-page { font-variant-numeric: tabular-nums; font-weight: 600; color: var(--slate-light); }

.manual-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}

.guide-text {
  font-size: 0.9rem;
  color: var(--slate-light);
  margin-bottom: 1rem;
  line-height: 1.5;
}

.guide-text code {
  background: var(--cloud-dancer-dark);
  padding: 0.2em 0.4em;
  border-radius: 4px;
}

textarea {
  width: 100%;
  height: 150px;
  padding: 1rem;
  border: 1px solid var(--border-glass);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.8);
  font-family: 'Noto Sans KR', monospace;
  font-size: 0.95rem;
  resize: vertical;
  outline: none;
  transition: border-color 0.2s;
  color: var(--slate);
}
textarea:focus { border-color: var(--amber); }

.secondary-btn {
  margin-top: 1rem;
  background: var(--cloud-dancer-dark);
  color: var(--slate);
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  width: 100%;
}
.secondary-btn:hover { background: #d0ceca; }

.preview-box {
  margin-top: 1rem;
  background: #fff;
  border-radius: 8px;
  padding: 1rem;
  display: none;
}
.preview-box.show { display: block; }

.ai-prompt-help {
  position: relative;
  display: inline-block;
  cursor: help;
}
.help-icon {
  background: #fff;
  border-radius: 50%;
  width: 24px; height: 24px;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}
.tooltip {
  visibility: hidden;
  width: 280px;
  background-color: var(--slate);
  color: #fff;
  text-align: left;
  border-radius: 8px;
  padding: 1rem;
  position: absolute;
  z-index: 10;
  bottom: 125%;
  right: 0;
  opacity: 0;
  transition: opacity 0.3s;
  font-size: 0.85rem;
  line-height: 1.4;
  box-shadow: var(--shadow-md);
}
.ai-prompt-help:hover .tooltip {
  visibility: visible;
  opacity: 1;
}

.action-bar { margin-top: 0.5rem; }

.primary-btn {
  width: 100%;
  background: var(--amber);
  color: #fff;
  border: none;
  padding: 1.25rem;
  border-radius: 16px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 4px 15px rgba(230, 126, 34, 0.3);
}

.primary-btn:hover:not(:disabled) {
  background: var(--amber-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(230, 126, 34, 0.4);
}

.primary-btn:disabled {
  background: #bdc3c7;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.overlay {
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(4px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 20;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--cloud-dancer-dark);
  border-top-color: var(--amber);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: 1rem;
}

@keyframes spin { 100% { transform: rotate(360deg); } }

/* Custom Toggle Switch for ZIP vs Single */
.custom-toggle {
  display: flex;
  align-items: center;
  cursor: pointer;
  gap: 0.75rem;
  font-weight: 500;
  color: var(--slate);
  font-size: 0.95rem;
}

.custom-toggle input {
  display: none;
}

.toggle-slider {
  position: relative;
  width: 44px;
  height: 24px;
  background-color: var(--slate-light);
  border-radius: 20px;
  transition: all 0.3s;
}

.toggle-slider::after {
  content: '';
  position: absolute;
  top: 3px;
  left: 3px;
  width: 18px;
  height: 18px;
  background-color: white;
  border-radius: 50%;
  transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.custom-toggle input:checked + .toggle-slider {
  background-color: var(--amber);
}

.custom-toggle input:checked + .toggle-slider::after {
  transform: translateX(20px);
}