/* ===== Reset & base ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  height: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100%;
  font-family: Tahoma, "Segoe UI", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-deep);
  overflow-x: hidden;
  direction: rtl;
}

/* ===== Space background ===== */
#bg-canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

.nebula {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 80% 50% at 20% 30%, var(--nebula-1), transparent 60%),
    radial-gradient(ellipse 60% 40% at 80% 70%, var(--nebula-2), transparent 55%),
    radial-gradient(ellipse 50% 60% at 50% 50%, var(--nebula-3), transparent 50%);
  animation: nebula-drift 60s ease-in-out infinite alternate;
}

@keyframes nebula-drift {
  0% { opacity: 0.7; transform: scale(1) translate(0, 0); }
  50% { opacity: 1; transform: scale(1.05) translate(2%, -1%); }
  100% { opacity: 0.8; transform: scale(1.02) translate(-1%, 2%); }
}

/* ===== Glass utility ===== */
.glass {
  background: var(--bg-surface);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

/* ===== Top bar ===== */
.top-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.6rem 1rem;
  padding-top: max(0.6rem, env(safe-area-inset-top));
  border-bottom: 1px solid var(--border);
  border-radius: 0;
}

.novel-title {
  flex: 1;
  font-size: 1rem;
  font-weight: 600;
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border: none;
  border-radius: 0.5rem;
  background: transparent;
  color: var(--text-primary);
  font-size: 1.25rem;
  cursor: pointer;
  transition: background 0.15s ease;
  flex-shrink: 0;
}

.icon-btn:hover {
  background: var(--btn-hover);
}

.icon-btn:active {
  background: var(--btn-active);
}

.icon-btn:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}

/* ===== Drawers ===== */
.drawer {
  position: fixed;
  top: 0;
  bottom: 0;
  width: min(320px, 88vw);
  z-index: 200;
  display: flex;
  flex-direction: column;
  transform: translateX(100%);
  transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 0;
}

#toc-drawer {
  right: 0;
  border-left: 1px solid var(--border);
}

#settings-panel {
  left: 0;
  right: auto;
  transform: translateX(-100%);
  border-right: 1px solid var(--border);
}

#toc-drawer.open,
#settings-panel.open {
  transform: translateX(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1rem 0.75rem;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.drawer-header h2 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
}

.toc-list {
  flex: 1;
  overflow-y: auto;
  padding: 0.5rem 0;
  -webkit-overflow-scrolling: touch;
}

.toc-item {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  width: 100%;
  padding: 0.85rem 1.25rem;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.95rem;
  text-align: right;
  cursor: pointer;
  transition: background 0.12s ease, color 0.12s ease;
  border-right: 3px solid transparent;
}

.toc-item .toc-check {
  flex-shrink: 0;
  width: 1.4rem;
  height: 1.4rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: 1.5px solid var(--border-strong);
  background: transparent;
  font-size: 0.75rem;
  color: transparent;
  line-height: 1;
  padding: 0;
  cursor: pointer;
  font-family: inherit;
  transition: background 0.12s ease, border-color 0.12s ease, color 0.12s ease, transform 0.1s ease;
}

.toc-item .toc-check:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: scale(1.08);
}

.toc-item .toc-check:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}

.toc-item.read .toc-check {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 700;
}

.toc-item .toc-label {
  flex: 1;
  text-align: right;
  line-height: 1.4;
  border: none;
  background: transparent;
  color: inherit;
  font-family: inherit;
  font-size: inherit;
  font-weight: inherit;
  cursor: pointer;
  padding: 0;
}

.toc-item .toc-label:hover {
  color: var(--text-primary);
}

.toc-item:hover {
  background: var(--btn-hover);
  color: var(--text-primary);
}

.toc-item.active {
  background: var(--accent-soft);
  color: var(--accent);
  border-right-color: var(--accent);
  font-weight: 600;
}

.toc-item.active .toc-label {
  color: var(--accent);
}

.toc-item:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: -2px;
}

.overlay {
  position: fixed;
  inset: 0;
  z-index: 150;
  background: var(--overlay);
  opacity: 0;
  transition: opacity 0.25s ease;
  pointer-events: none;
}

.overlay.visible {
  opacity: 1;
  pointer-events: auto;
}

/* ===== Settings ===== */
.settings-body {
  flex: 1;
  overflow-y: auto;
  padding: 1rem 1.25rem 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.setting-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.setting-group label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.range-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.range-row input[type="range"] {
  flex: 1;
  height: 4px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--border-strong);
  border-radius: 2px;
  outline: none;
}

.range-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}

.range-row input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: none;
}

.range-btn {
  width: 2rem;
  height: 2rem;
  border: 1px solid var(--border);
  border-radius: 0.4rem;
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-size: 1.1rem;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.12s ease;
}

.range-btn:hover {
  background: var(--btn-hover);
}

.setting-value {
  font-size: 0.8rem;
  color: var(--text-muted);
  text-align: center;
}

select {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%23a0aec0' d='M1 1l5 5 5-5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: left 0.75rem center;
  padding-left: 2rem;
}

select:focus {
  outline: 2px solid var(--focus-ring);
  outline-offset: 1px;
}

.theme-buttons {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.theme-btn {
  flex: 1;
  min-width: 4.5rem;
  padding: 0.55rem 0.5rem;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  background: var(--bg-elevated);
  color: var(--text-secondary);
  font-family: inherit;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.theme-btn:hover {
  background: var(--btn-hover);
  color: var(--text-primary);
}

.theme-btn.active {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
}

.theme-btn:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}

/* ===== Reader ===== */
.reader {
  position: relative;
  z-index: 10;
  min-height: 100vh;
  padding: 4.5rem 1rem 5.5rem;
  display: flex;
  justify-content: center;
  width: 100%;
}

.chapter-content {
  width: 100%;
  max-width: min(var(--content-width, 860px), calc(100vw - 1.5rem));
  padding: 2rem 1.75rem 3rem;
  border-radius: 1rem;
  min-height: 60vh;
}

.loading-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 4rem 1rem;
  color: var(--text-muted);
}

.spinner {
  width: 36px;
  height: 36px;
  border: 3px solid var(--border);
  border-top-color: var(--spinner);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.chapter-body {
  font-size: var(--font-size, 18px);
  line-height: var(--line-height, 1.8);
  font-family: var(--font-family, Tahoma, "Segoe UI", sans-serif);
  color: var(--text-primary);
  text-align: right;
}

.chapter-body .chapter-heading {
  font-size: 1.35em;
  font-weight: 700;
  margin-bottom: 1.75rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-primary);
  line-height: 1.4;
}

.chapter-body p {
  margin-bottom: 1.15em;
  text-align: justify;
  text-justify: inter-word;
  hyphens: auto;
  -webkit-hyphens: auto;
}

.chapter-body p:last-child {
  margin-bottom: 0;
}

.chapter-body .scene-header {
  margin: 2em 0 1em;
  font-size: 0.9em;
  color: var(--text-muted);
  font-style: italic;
  text-align: center;
  border: none;
  padding: 0;
}

/* ===== Bottom nav ===== */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.65rem 1rem;
  padding-bottom: max(0.65rem, env(safe-area-inset-bottom));
  border-top: 1px solid var(--border);
  border-radius: 0;
}

.nav-btn {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.5rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.12s ease, opacity 0.12s ease;
}

.nav-btn:hover:not(:disabled) {
  background: var(--btn-hover);
}

.nav-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.nav-btn:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}

.nav-arrow {
  font-size: 1rem;
  line-height: 1;
}

.chapter-indicator {
  flex: 1;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ===== Responsive ===== */
@media (max-width: 600px) {
  .reader {
    padding: 4rem 0.35rem 5rem;
  }

  .chapter-content {
    padding: 1.35rem 0.9rem 2.5rem;
    border-radius: 0.75rem;
    max-width: calc(100vw - 0.7rem);
  }

  .novel-title {
    font-size: 0.9rem;
  }

  .nav-label {
    display: none;
  }

  .nav-btn {
    padding: 0.55rem 0.9rem;
  }

  .nav-arrow {
    font-size: 1.2rem;
  }
}

@media (min-width: 768px) {
  .reader {
    padding: 4.75rem 1.5rem 5.75rem;
  }

  .chapter-content {
    padding: 2.5rem 2.75rem 3.5rem;
  }
}

@media (min-width: 1024px) {
  .drawer {
    width: 340px;
  }

  .reader {
    padding-left: 2rem;
    padding-right: 2rem;
  }

  .chapter-content {
    padding: 2.75rem 3.25rem 4rem;
  }
}

@media (min-width: 1280px) {
  .chapter-content {
    max-width: min(var(--content-width, 920px), calc(100vw - 3rem));
  }
}

/* Reduce motion */
@media (prefers-reduced-motion: reduce) {
  .nebula {
    animation: none;
  }

  .drawer,
  .overlay {
    transition: none;
  }

  .spinner {
    animation-duration: 1.5s;
  }
}

/* Print */
@media print {
  #bg-canvas,
  .nebula,
  .top-bar,
  .bottom-nav,
  .drawer,
  .overlay {
    display: none !important;
  }

  .reader {
    padding: 0;
  }

  .chapter-content {
    max-width: none;
    box-shadow: none;
    border: none;
    background: white;
    color: black;
  }
}