/**
 * Novel Theme - Header Styles
 * Header, controls, navigation, theme toggle
 */

/* Header */
.reader-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1rem;
  z-index: 100;
  transition: transform 0.3s ease, background-color 0.3s ease;
}

.reader-header.is-hidden {
  transform: translateY(-100%);
}

.reader-header.is-fixed {
  box-shadow: 0 2px 8px var(--shadow);
}

.header-left,
.header-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.back-to-dashboard {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.625rem;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 6px;
  transition: all 0.15s ease;
}

.back-to-dashboard:hover {
  color: var(--accent);
  background: var(--accent-bg);
}

.back-to-dashboard svg {
  flex-shrink: 0;
}

.header-divider {
  width: 1px;
  height: 20px;
  background: var(--border);
  margin: 0 0.25rem;
}

.header-center {
  flex: 1;
  text-align: center;
  overflow: hidden;
}

.doc-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.icon-btn {
  background: transparent;
  border: none;
  padding: 0.5rem;
  cursor: pointer;
  color: var(--text-secondary);
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}

.icon-btn:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

/* Back button (link styled as icon-btn) */
a.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  padding: 0.5rem;
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}

a.icon-btn.back-btn {
  color: var(--text-secondary);
}

a.icon-btn.back-btn:hover {
  color: var(--accent);
  background: var(--bg-tertiary);
}

/* Header Navigation (prev/next in header) */
.header-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin-left: 0.5rem;
  padding-left: 0.5rem;
  border-left: 1px solid var(--border);
}

.header-nav-btn {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.375rem 0.625rem;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.8125rem;
  font-weight: 500;
  border-radius: 6px;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.header-nav-btn:hover {
  color: var(--accent);
  background: var(--bg-tertiary);
  text-decoration: none;
}

.header-nav-btn svg {
  flex-shrink: 0;
}

.header-nav-btn.prev svg {
  margin-right: 0.125rem;
}

.header-nav-btn.next svg {
  margin-left: 0.125rem;
}

/* Theme toggle icons */
.sun-icon { display: block; }
.moon-icon { display: none; }
[data-theme="dark"] .sun-icon { display: none; }
[data-theme="dark"] .moon-icon { display: block; }

/* Font controls */
.font-controls {
  display: flex;
  gap: 2px;
  background: var(--bg-tertiary);
  border-radius: 6px;
  padding: 2px;
}

.font-btn {
  background: transparent;
  border: none;
  padding: 0.25rem 0.5rem;
  cursor: pointer;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 4px;
  transition: all 0.2s;
}

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

.font-btn.active {
  background: var(--bg-primary);
  color: var(--accent);
  box-shadow: 0 1px 2px var(--shadow);
}

/* Progress bar */
.progress-bar-container {
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  height: 3px;
  background: var(--bg-tertiary);
  z-index: 99;
  transition: top 0.3s ease;
}

.reader-header.is-hidden ~ .progress-bar-container {
  top: 0;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-hover));
  transition: width 0.1s ease-out;
}