/* =============================================
   SpikeRead — styles.css
   Mobile-first. Single file with section headers.
   Section order matches architecture.md §1.3.
============================================== */


/* ===== RESET & BASE ===== */

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.5;
  min-height: 100dvh;
  overflow-x: hidden;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input,
textarea,
select {
  font-family: inherit;
  font-size: inherit;
}

textarea {
  resize: vertical;
}

img,
svg {
  display: block;
  max-width: 100%;
}

/* Screen-reader-only utility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


/* ===== CSS VARIABLES ===== */

/* JR Light theme (default) — other themes defined in a later task */
:root {
  /* Colour palette */
  --bg-color:         #ffffff;
  --text-color:       #212121;
  --text-muted:       #666666;
  --accent-color:     #0E394F;
  --orp-color:        #9C1C29;
  --marker-color:     #77BDD9;
  --underline-color:  #0C6C9C;
  --surface-color:    #f5f5f5;
  --border-color:     #e0e0e0;
  --success-color:    #8F9E17;
  --link-color:       #0C6C9C;

  /* Typography */
  --font-family:      -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-base:   1rem;

  /* Spacing */
  --space-xs:   0.25rem;
  --space-sm:   0.5rem;
  --space-md:   1rem;
  --space-lg:   1.5rem;
  --space-xl:   2rem;
  --space-2xl:  3rem;

  /* Layout */
  --nav-height:       3.5rem;
  --max-content-width: 44rem;   /* comfortable reading column */

  /* Transitions */
  --transition-fast:  150ms ease;
  --transition-base:  250ms ease;
}


/* ===== THEME DEFINITIONS ===== */

[data-theme="jr-dark"] {
  /* JR Dark - Deep Teal on near-black */
  --bg-color: #212121;
  --text-color: #f5f5f5;
  --text-muted: #999999;
  --accent-color: #1EA4D9;
  --orp-color: #F22E62;
  --marker-color: #0E394F;
  --underline-color: #1EA4D9;
  --surface-color: #2d2d2d;
  --border-color: #404040;
  --success-color: #81B800;
  --link-color: #77BDD9;
}

[data-theme="jr-ocean"] {
  /* JR Ocean - Blue-focused reading theme */
  --bg-color: #0E394F;
  --text-color: #ffffff;
  --text-muted: #77BDD9;
  --accent-color: #1EA4D9;
  --orp-color: #F22E62;
  --marker-color: #1B80BF;
  --underline-color: #77BDD9;
  --surface-color: #0C6C9C;
  --border-color: #1B80BF;
  --success-color: #81B800;
  --link-color: #77BDD9;
}

[data-theme="sepia"] {
  /* Classic sepia for extended reading */
  --bg-color: #f4ecd8;
  --text-color: #5b4636;
  --text-muted: #8b7355;
  --accent-color: #8b7355;
  --orp-color: #9C1C29;
  --marker-color: #e6d5a8;
  --underline-color: #8b7355;
  --surface-color: #ebe3d0;
  --border-color: #d4c9b0;
  --success-color: #8F9E17;
  --link-color: #0C6C9C;
}

[data-theme="high-contrast"] {
  /* Pure black/white for maximum readability */
  --bg-color: #000000;
  --text-color: #ffffff;
  --text-muted: #cccccc;
  --accent-color: #ffffff;
  --orp-color: #F22E62;
  --marker-color: #0E394F;
  --underline-color: #1EA4D9;
  --surface-color: #1a1a1a;
  --border-color: #333333;
  --success-color: #81B800;
  --link-color: #2D9AFF;
}

[data-theme="charcoal"] {
  /* Soft dark theme, easier on eyes than pure black */
  --bg-color: #222224;
  --text-color: #e8e8e8;
  --text-muted: #888888;
  --accent-color: #0C6C9C;
  --orp-color: #BF2C47;
  --marker-color: #0E394F;
  --underline-color: #1B80BF;
  --surface-color: #2d2d30;
  --border-color: #404040;
  --success-color: #8F9E17;
  --link-color: #77BDD9;
}


/* ===== FONT FACE DECLARATIONS ===== */

@font-face {
  font-family: 'OpenDyslexic';
  src: url('../assets/fonts/OpenDyslexic-Regular.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'OpenDyslexic';
  src: url('../assets/fonts/OpenDyslexic-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}


/* ===== FONT FAMILY DEFINITIONS ===== */

[data-font="system"] {
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

[data-font="new-york"] {
  --font-family: 'New York', Georgia, 'Times New Roman', serif;
}

[data-font="opendyslexic"] {
  --font-family: 'OpenDyslexic', sans-serif;
}


/* ===== FONT SIZE DEFINITIONS ===== */

[data-font-size="small"] {
  --flash-font-size: clamp(1.2rem, 6vw, 2.5rem);
  --guide-font-size: clamp(0.875rem, 3.5vw, 1.1rem);
}

[data-font-size="default"] {
  --flash-font-size: clamp(1.5rem, 8vw, 3rem);
  --guide-font-size: clamp(1rem, 4vw, 1.25rem);
}

[data-font-size="large"] {
  --flash-font-size: clamp(2rem, 10vw, 4rem);
  --guide-font-size: clamp(1.25rem, 5vw, 1.5rem);
}


/* ===== TEXT ALIGNMENT DEFINITIONS ===== */

[data-text-align="left"] {
  --text-align: left;
}

[data-text-align="center"] {
  --text-align: center;
}

[data-text-align="justify"] {
  --text-align: justify;
}


/* ===== LAYOUT & NAVIGATION ===== */

/* App wrapper: fills the full viewport, reserves space for bottom nav */
.app {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
}

/* Main content area fills remaining space above nav */
.main-content {
  flex: 1;
  position: relative;
  overflow: hidden;
  /* Leave room at the bottom for the fixed nav bar */
  padding-bottom: var(--nav-height);
}

/* ----- View containers ----- */

/* All views are hidden by default */
.view {
  display: none;
  width: 100%;
  height: 100%;
}

/* Only the active view is visible */
.view--active {
  display: flex;
  flex-direction: column;
}

/* ----- Bottom navigation bar ----- */

.nav-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  display: flex;
  align-items: stretch;
  background-color: var(--surface-color);
  border-top: 1px solid var(--border-color);
  z-index: 100;
  /* Respect safe area insets on notched devices */
  padding-bottom: env(safe-area-inset-bottom, 0);
}

.nav-btn {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-sm);
  color: var(--text-muted);
  font-size: 0.75rem;
  line-height: 1.2;
  transition: color var(--transition-fast);
  -webkit-tap-highlight-color: transparent;
}

.nav-btn:hover,
.nav-btn:focus-visible {
  color: var(--accent-color);
  outline: 2px solid var(--accent-color);
  outline-offset: -2px;
}

.nav-btn--active {
  color: var(--accent-color);
  font-weight: 600;
}

.nav-btn__icon {
  font-size: 1rem;
  line-height: 1;
  letter-spacing: -0.05em;
}

.nav-btn__label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* ----- Toast notifications ----- */

.toast-container {
  position: fixed;
  bottom: calc(var(--nav-height) + var(--space-sm));
  left: var(--space-md);
  right: var(--space-md);
  z-index: 200;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  pointer-events: none;
}

.toast {
  background-color: var(--accent-color);
  color: #ffffff;
  padding: var(--space-sm) var(--space-md);
  border-radius: 0.375rem;
  font-size: 0.875rem;
  pointer-events: auto;
  animation: toast-in var(--transition-base) forwards;
}

.toast--error {
  background-color: var(--orp-color);
}

@keyframes toast-in {
  from { opacity: 0; transform: translateY(0.5rem); }
  to   { opacity: 1; transform: translateY(0); }
}


/* ===== INPUT VIEW ===== */

.input-view {
  align-items: center;
  justify-content: flex-start;
  padding: var(--space-xl) var(--space-md);
  overflow-y: auto;
}

.input-view__inner {
  width: 100%;
  max-width: var(--max-content-width);
  margin: 0 auto;
}

.input-view__title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent-color);
  margin-bottom: var(--space-sm);
  text-align: center;
}

.input-view__tagline {
  color: var(--text-muted);
  font-size: 0.9375rem;
  text-align: center;
  margin-bottom: var(--space-xl);
}

.input-view__actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.input-view__action-btn {
  display: block;
  width: 100%;
  padding: var(--space-md) var(--space-lg);
  background-color: var(--accent-color);
  color: #ffffff;
  border-radius: 0.375rem;
  font-size: 1rem;
  font-weight: 600;
  text-align: center;
  transition: opacity var(--transition-fast);
}

.input-view__action-btn:hover,
.input-view__action-btn:focus-visible {
  opacity: 0.88;
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

.input-view__action-btn--disabled {
  background-color: var(--border-color);
  color: var(--text-muted);
  cursor: not-allowed;
}

.input-view__coming-soon {
  font-size: 0.8em;
  font-weight: 400;
}

.input-view__file-input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

/* Textarea wrapper: hidden until Paste or Add Text is triggered */
.input-view__textarea-wrap {
  display: none;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.input-view__textarea-wrap--visible {
  display: flex;
}

.input-view__textarea {
  width: 100%;
  padding: var(--space-md);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  background-color: var(--surface-color);
  color: var(--text-color);
  font-size: 0.9375rem;
  line-height: 1.6;
  min-height: 12rem;
}

.input-view__textarea:focus {
  outline: 2px solid var(--accent-color);
  outline-offset: 0;
}

.input-view__textarea-actions {
  display: flex;
  gap: var(--space-sm);
}

.input-view__submit-btn {
  flex: 1;
  padding: var(--space-sm) var(--space-md);
  background-color: var(--accent-color);
  color: #ffffff;
  border-radius: 0.375rem;
  font-size: 0.9375rem;
  font-weight: 600;
  transition: opacity var(--transition-fast);
}

.input-view__submit-btn:hover,
.input-view__submit-btn:focus-visible {
  opacity: 0.88;
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

.input-view__cancel-btn {
  padding: var(--space-sm) var(--space-md);
  color: var(--text-muted);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.9375rem;
  transition: color var(--transition-fast);
}

.input-view__cancel-btn:hover,
.input-view__cancel-btn:focus-visible {
  color: var(--text-color);
  outline: 2px solid var(--border-color);
  outline-offset: 2px;
}

/* URL input wrap */
.input-view__url-wrap {
  display: none;
  flex-direction: column;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.input-view__url-wrap--visible {
  display: flex;
}

.input-view__url-input {
  width: 100%;
  padding: var(--space-md);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  background-color: var(--surface-color);
  color: var(--text-color);
  font-size: 0.9375rem;
}

.input-view__url-input:focus {
  outline: 2px solid var(--accent-color);
  outline-offset: 0;
}

.input-view__url-actions {
  display: flex;
  gap: var(--space-sm);
}

/* Drag-and-drop zone */
.input-view__drop-zone {
  border: 2px dashed var(--border-color);
  border-radius: 0.5rem;
  padding: var(--space-xl) var(--space-md);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
  transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.input-view__drop-zone--over {
  border-color: var(--accent-color);
  background-color: var(--surface-color);
  color: var(--accent-color);
}


/* ===== FLASH MODE ===== */

.flash-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 2rem;
}

.flash-word {
  display: flex;
  align-items: baseline;
  flex-wrap: nowrap;
  white-space: nowrap;
  font-size: var(--flash-font-size, clamp(1.5rem, 8vw, 3rem));
  font-family: var(--font-family);
  line-height: 1.4;
}

.flash-word--center {
  justify-content: center;
}

.flash-word--edge {
  justify-content: flex-start;
  padding-left: 10%;
}

.flash-word__before {
  text-align: right;
  flex: 1 1 0;
}

.flash-word__orp {
  color: var(--orp-color, #e53935);
  font-weight: 600;
  flex: 0 0 auto;
}

.flash-word__after {
  text-align: left;
  flex: 1 1 0;
}


/* ===== GUIDE MODE ===== */

.guide-container {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  max-width: 65ch;
  margin: 0 auto;
  font-size: var(--guide-font-size, clamp(1rem, 4vw, 1.25rem));
  font-family: var(--font-family);
  line-height: 1.8;
}

.guide-paragraph {
  margin-bottom: 1.5em;
  text-align: var(--text-align, left);
}

.guide-chunk {
  transition: opacity 0.15s ease, background-color 0.15s ease;
  border-radius: 2px;
  padding: 0 2px;
}

/* Dimmer style — default dim for all chunks, active gets full opacity */
.guide-container[data-style="dimmer"] .guide-chunk {
  opacity: 0.5;
}

.guide-container[data-style="dimmer"] .guide-chunk--active {
  opacity: 1 !important;
  font-weight: 500;
}

.guide-container[data-style="dimmer"] .guide-chunk--past {
  opacity: 1;
}

/* Marker style */
.guide-container[data-style="marker"] .guide-chunk--active {
  background-color: var(--marker-color, #fff59d);
}

.guide-container[data-style="marker"] .guide-chunk--past {
  background-color: var(--marker-color-past, #fff9c4);
}

/* Underline style */
.guide-container[data-style="underline"] .guide-chunk--active {
  text-decoration: underline;
  text-decoration-color: var(--underline-color, #4caf50);
  text-decoration-thickness: 3px;
  text-underline-offset: 4px;
}

.guide-container[data-style="underline"] .guide-chunk--past {
  text-decoration: underline;
  text-decoration-color: var(--underline-color-past, #c8e6c9);
  text-decoration-thickness: 2px;
}


/* ===== CONTROLS ===== */

.controls {
  flex-shrink: 0;
  position: sticky;
  bottom: 0;
  z-index: 10;
  padding: var(--space-md);
  background-color: var(--surface-color);
  border-top: 1px solid var(--border-color);
}

.controls__progress-row {
  margin-bottom: var(--space-sm);
}

.controls__progress-bar {
  width: 100%;
  height: 4px;
  background-color: var(--border-color);
  border-radius: 2px;
  overflow: hidden;
  cursor: pointer;
}

.controls__progress-fill {
  height: 100%;
  background-color: var(--success-color);
  border-radius: 2px;
  transition: width 100ms linear;
  width: 0%;
}

.controls__info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8125rem;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
}

.controls__speed-row {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.controls__speed-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  min-width: 3rem;
}

.controls__speed-slider {
  flex: 1;
  height: 4px;
  accent-color: var(--accent-color);
}

.controls__transport {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-lg);
}

.controls__btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  color: var(--text-color);
  font-size: 0.875rem;
  font-weight: 600;
  transition: background-color var(--transition-fast);
}

.controls__btn:hover,
.controls__btn:focus-visible {
  background-color: var(--border-color);
}

.controls__btn--play-pause {
  width: 3.5rem;
  height: 3.5rem;
  background-color: var(--accent-color);
  color: #ffffff;
  font-size: 1rem;
}

.controls__btn--play-pause:hover,
.controls__btn--play-pause:focus-visible {
  opacity: 0.88;
}


/* ===== SETTINGS PANEL ===== */

.settings-panel {
  position: fixed;
  inset: 0;
  z-index: 150;
  background-color: var(--bg-color);
  overflow-y: auto;
  padding-bottom: var(--nav-height);
}

.settings-panel__inner {
  max-width: 480px;
  margin: 0 auto;
  padding: var(--space-md);
}

.settings-panel__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-md) 0;
  margin-bottom: var(--space-md);
  border-bottom: 1px solid var(--border-color);
}

.settings-panel__title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-color);
}

.settings-panel__close {
  width: 2.5rem;
  height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: var(--text-muted);
  border-radius: 50%;
  transition: background-color var(--transition-fast);
}

.settings-panel__close:hover,
.settings-panel__close:focus-visible {
  background-color: var(--surface-color);
  color: var(--text-color);
}

.settings-section {
  margin-bottom: var(--space-lg);
}

.settings-section__title {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
}

.setting-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-sm) 0;
  min-height: 2.75rem;
}

.setting-row__label {
  font-size: 0.9375rem;
  color: var(--text-color);
}

.setting-row__value {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Mode selector buttons */
.mode-selector {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.mode-btn {
  flex: 1;
  padding: var(--space-md);
  border: 2px solid var(--border-color);
  border-radius: 0.5rem;
  background-color: var(--surface-color);
  text-align: center;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-color);
  transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.mode-btn:hover {
  border-color: var(--accent-color);
}

.mode-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}

/* Style selector (dimmer/marker/underline) */
.style-selector {
  display: flex;
  gap: var(--space-xs);
}

.style-btn {
  flex: 1;
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-color);
  background-color: var(--surface-color);
  text-align: center;
  transition: all var(--transition-fast);
}

.style-btn:hover {
  border-color: var(--accent-color);
}

.style-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}

/* Theme selector */
.theme-selector {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.theme-btn {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  border: 2px solid var(--border-color);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.theme-btn:hover {
  transform: scale(1.1);
}

.theme-btn--active {
  border-color: var(--accent-color);
  border-width: 3px;
}

.theme-btn--light { background-color: #ffffff; }
.theme-btn--jr-dark { background-color: #212121; }
.theme-btn--jr-ocean { background-color: #0E394F; }
.theme-btn--sepia { background-color: #f4ecd8; }
.theme-btn--high-contrast { background-color: #000000; }
.theme-btn--charcoal { background-color: #222224; }

/* Font size buttons */
.font-size-control {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.font-size-btn {
  width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  color: var(--text-color);
  transition: background-color var(--transition-fast);
}

.font-size-btn:hover {
  background-color: var(--surface-color);
}

.font-size-btn--small { font-size: 0.75rem; }
.font-size-btn--large { font-size: 1.25rem; font-weight: 600; }

/* Toggle switch */
.toggle-switch {
  position: relative;
  width: 3rem;
  height: 1.5rem;
}

.toggle-switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-switch label {
  position: absolute;
  inset: 0;
  cursor: pointer;
  background-color: var(--border-color);
  border-radius: 1rem;
  transition: background-color var(--transition-fast);
}

.toggle-switch label::after {
  content: '';
  position: absolute;
  width: 1.125rem;
  height: 1.125rem;
  left: 0.1875rem;
  bottom: 0.1875rem;
  background-color: #ffffff;
  border-radius: 50%;
  transition: transform var(--transition-fast);
}

.toggle-switch input:checked + label {
  background-color: var(--accent-color);
}

.toggle-switch input:checked + label::after {
  transform: translateX(1.5rem);
}

/* Speed control in settings */
.speed-control {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.speed-btn {
  width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-color);
  transition: background-color var(--transition-fast);
}

.speed-btn:hover {
  background-color: var(--surface-color);
}

.speed-control input[type="range"] {
  flex: 1;
  accent-color: var(--accent-color);
}

/* Text align selector */
.align-selector {
  display: flex;
  gap: var(--space-xs);
}

.align-btn {
  flex: 1;
  padding: var(--space-sm);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.8125rem;
  text-align: center;
  color: var(--text-color);
  background-color: var(--surface-color);
  transition: all var(--transition-fast);
}

.align-btn:hover {
  border-color: var(--accent-color);
}

.align-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}

/* Font selector */
.font-selector {
  display: flex;
  gap: var(--space-xs);
  flex-wrap: wrap;
}

.font-btn {
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.8125rem;
  color: var(--text-color);
  background-color: var(--surface-color);
  transition: all var(--transition-fast);
}

.font-btn:hover {
  border-color: var(--accent-color);
}

.font-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}


/* ===== ADVANCED PREFERENCES ===== */

/* Sub-panel container */
.advanced-panel {
  /* No extra styles needed at container level; children handle layout */
}

/* Header row: back button + panel title */
.advanced-panel__header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

/* Back button — styled as an accent-coloured text link */
.advanced-panel__back {
  border: none;
  background: none;
  color: var(--accent-color);
  font-size: 0.9375rem;
  cursor: pointer;
  padding: var(--space-xs) var(--space-sm);
  transition: opacity var(--transition-fast);
}

.advanced-panel__back:hover,
.advanced-panel__back:focus-visible {
  opacity: 0.75;
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

/* Sub-panel title */
.advanced-panel__title {
  font-size: 1.125rem;
  font-weight: 600;
  margin: 0;
  color: var(--text-color);
}

/* Clickable setting row — navigates to a sub-panel */
.setting-row--clickable {
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  transition: background-color var(--transition-fast);
  border-radius: 0.375rem;
  padding: var(--space-sm) var(--space-xs);
  margin: 0 calc(var(--space-xs) * -1);
}

.setting-row--clickable:hover {
  background-color: var(--surface-color);
}

/* Chevron arrow on clickable rows */
.setting-row__chevron {
  color: var(--text-muted-color, #999);
  font-size: 1.25rem;
  line-height: 1;
  flex-shrink: 0;
}

/* Horizontal group of toggle buttons (e.g. ORP position, metronome sounds) */
.toggle-group {
  display: flex;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
}

/* Individual toggle button within a group */
.toggle-btn {
  flex: 1;
  padding: var(--space-sm);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.8125rem;
  text-align: center;
  color: var(--text-color);
  background: var(--surface-color);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.toggle-btn:hover {
  border-color: var(--accent-color);
}

/* Active toggle button */
.toggle-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}

/* Pause level button group (None / Short / Med / Long) */
.pause-level-group {
  display: flex;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
}

/* Individual pause level button — matches .toggle-btn styling */
.pause-btn {
  flex: 1;
  padding: var(--space-sm);
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  font-size: 0.8125rem;
  text-align: center;
  color: var(--text-color);
  background: var(--surface-color);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.pause-btn:hover {
  border-color: var(--accent-color);
}

/* Active pause level button */
.pause-btn--active {
  border-color: var(--accent-color);
  background-color: var(--accent-color);
  color: #ffffff;
}

/* iOS-style toggle switch — slider variant used in advanced panels */
/* Note: the existing .toggle-switch in SETTINGS PANEL uses a <label> element.
   This variant uses a .toggle-switch__slider sibling span for new panels. */
.toggle-switch__slider {
  position: absolute;
  inset: 0;
  background-color: var(--border-color);
  border-radius: 12px;
  transition: background-color 0.2s ease;
  cursor: pointer;
}

.toggle-switch__slider::before {
  content: '';
  position: absolute;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background-color: #ffffff;
  bottom: 3px;
  left: 3px;
  transition: transform 0.2s ease;
}

.toggle-switch input:checked + .toggle-switch__slider {
  background-color: var(--accent-color);
}

.toggle-switch input:checked + .toggle-switch__slider::before {
  transform: translateX(20px);
}


/* ===== LIBRARY VIEW ===== */

.library-view {
  display: flex;
  flex-direction: column;
  flex: 1;
  height: 100%;
  overflow: hidden;
}

.library-view__inner {
  display: flex;
  flex-direction: column;
  flex: 1;
  padding: var(--space-lg) var(--space-md);
  overflow-y: auto;
  gap: var(--space-md);
}

.library-view__title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-color);
  flex-shrink: 0;
}

/* Filter pill tabs */
.library-view__filters {
  display: flex;
  gap: var(--space-sm);
  flex-shrink: 0;
  flex-wrap: wrap;
}

.library-view__filter {
  padding: var(--space-xs) var(--space-md);
  border-radius: 1rem;
  border: 1px solid var(--border-color);
  background-color: var(--surface-color);
  color: var(--text-muted);
  font-size: 0.875rem;
  font-weight: 500;
  transition: background-color var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.library-view__filter:hover,
.library-view__filter:focus-visible {
  border-color: var(--accent-color);
  color: var(--accent-color);
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

.library-view__filter--active {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
  color: #ffffff;
}

.library-view__filter--active:hover,
.library-view__filter--active:focus-visible {
  color: #ffffff;
  opacity: 0.88;
}

/* Card list */
.library-view__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

/* Empty state */
.library-view__empty {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-2xl) var(--space-md);
  color: var(--text-muted);
  font-size: 0.9375rem;
  text-align: center;
}

/* Library card */
.library-card {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: var(--space-md);
  padding: 0.75rem 1rem;
  background-color: var(--surface-color);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: background-color var(--transition-fast), border-color var(--transition-fast);
}

.library-card:hover {
  background-color: var(--bg-color);
  border-color: var(--accent-color);
}

/* Card content: title + meta, takes up remaining space */
.library-card__content {
  flex: 1;
  min-width: 0; /* allows text-overflow: ellipsis to work in flex children */
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.library-card__title {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.library-card__meta {
  font-size: 0.8125rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Right column: progress + delete */
.library-card__right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: var(--space-xs);
  flex-shrink: 0;
}

/* Progress block: bar + percentage label */
.library-card__progress {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 2px;
}

.library-card__progress-bar {
  width: 3rem;
  height: 4px;
  background-color: var(--border-color);
  border-radius: 2px;
  overflow: hidden;
}

.library-card__progress-fill {
  height: 100%;
  background-color: var(--accent-color);
  border-radius: 2px;
  transition: width var(--transition-base);
}

.library-card__status {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1;
}

/* Delete button */
.library-card__delete {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 0.25rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.library-card__delete:hover,
.library-card__delete:focus-visible {
  background-color: var(--border-color);
  color: var(--text-color);
  outline: 2px solid var(--border-color);
  outline-offset: 1px;
}

.library-card__badge {
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-color);
  background-color: color-mix(in srgb, var(--accent-color) 12%, transparent);
  padding: 0.125rem 0.5rem;
  border-radius: 1rem;
}

.library-upload {
  margin-bottom: var(--space-sm);
}

.library-upload__btn {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  border: 2px dashed var(--border-color);
  border-radius: 0.5rem;
  color: var(--text-muted);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.library-upload__btn:hover,
.library-upload__btn:focus-visible {
  border-color: var(--accent-color);
  color: var(--accent-color);
}

.library-upload__input {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
}


/* ===== RESPONSIVE ===== */

/* Tablet — 768px and up */
@media (min-width: 768px) {

  /* Main content gets breathing room on the sides */
  .main-content {
    padding-left: 1.5rem;
    padding-right: 1.5rem;
  }

  /* Input view: constrain and centre the form column */
  .input-view__inner {
    max-width: 600px;
  }

  /* Action buttons sit side-by-side on tablet */
  .input-view__actions {
    flex-direction: row;
  }

  .input-view__actions .input-view__action-btn {
    flex: 1;
  }

  /* Flash display: larger word at tablet widths */
  .flash-word {
    --flash-font-size: clamp(2rem, 6vw, 3.5rem);
  }

  /* Guide container: horizontal padding + capped width */
  .guide-container {
    padding-left: 2rem;
    padding-right: 2rem;
    max-width: 700px;
  }

  /* Controls: constrain and centre */
  .controls {
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
  }

  /* Settings panel inner: slightly wider cap */
  .settings-panel__inner {
    max-width: 500px;
  }

  /* Nav buttons: a touch more padding on tablet */
  .nav-btn {
    padding: var(--space-sm) var(--space-md);
    font-size: 0.8125rem;
  }
}


/* Desktop — 1024px and up */
@media (min-width: 1024px) {

  /* More generous side padding at desktop */
  .main-content {
    padding-left: 2.5rem;
    padding-right: 2.5rem;
  }

  /* Input view: wider comfortable column */
  .input-view__inner {
    max-width: 700px;
  }

  /* Flash word: comfortable large size for desktop reading */
  .flash-word {
    --flash-font-size: clamp(2.5rem, 4vw, 4rem);
  }

  /* Guide container: desktop reading column */
  .guide-container {
    max-width: 800px;
    line-height: 1.9;
  }

  /* Controls: wider cap on desktop */
  .controls {
    max-width: 650px;
  }

  /* Settings panel: final desktop width */
  .settings-panel__inner {
    max-width: 550px;
  }

  /* Nav bar: don't stretch to full desktop width */
  .nav-bar {
    max-width: 400px;
    left: 50%;
    right: auto;
    transform: translateX(-50%);
    border-radius: 0.75rem 0.75rem 0 0;
  }
}