/**
 * =====================================================
 * FLOATING ACTION BUTTON - STYLES
 * =====================================================
 * Apple-inspired expandable button with bounce physics
 * Matches iPhone 17 Pro "All Access Pass" animation
 *
 * @author Claude
 * @version 2.0.0
 */

/* ==================== ROOT VARIABLES ==================== */
:root {
  /* Positioning */
  --fab-offset: 2rem;
  --fab-z-index: 9999;

  /* Sizes */
  --fab-collapsed-size: 44px;
  --fab-expanded-height: 44px;
  --fab-expanded-min-width: 160px;
  --fab-border-radius: 22px;

  /* Dark Theme Colors (Default) */
  --fab-bg-color: rgba(0, 0, 0, 0.85);
  --fab-text-color: #ffffff;
  --fab-halo-color: 59, 130, 246; /* RGB format */
  --fab-hover-bg: rgba(0, 0, 0, 0.95);
  --fab-focus-ring: rgba(59, 130, 246, 0.6);

  /* Animation Durations */
  --fab-appear-duration: 0.5s;
  --fab-expand-duration: 0.4s;
  --fab-bounce-duration: 0.3s;

  /* Easing Functions */
  --fab-spring-easing: cubic-bezier(0.34, 1.45, 0.64, 1);
  --fab-smooth-easing: cubic-bezier(0.4, 0, 0.2, 1);
  --fab-bounce-easing: cubic-bezier(0.68, -0.25, 0.265, 1.25);
  --fab-text-easing: cubic-bezier(0.25, 0.46, 0.45, 0.94);

  /* Halo Effect */
  --fab-halo-opacity: 0.25;
  --fab-halo-blur: 20px;
  --fab-halo-scale: 1.8;

  /* Shadows */
  --fab-shadow: 0 4px 12px rgba(0, 0, 0, 0.15),
                0 2px 4px rgba(0, 0, 0, 0.1);
  --fab-shadow-hover: 0 8px 20px rgba(0, 0, 0, 0.2),
                      0 4px 8px rgba(0, 0, 0, 0.15);
}

/* Light Theme */
.fab-container[data-theme="light"] {
  --fab-bg-color: rgba(255, 255, 255, 0.95);
  --fab-text-color: #1d1d1f;
  --fab-hover-bg: rgba(255, 255, 255, 1);
  --fab-shadow: 0 4px 16px rgba(0, 0, 0, 0.08),
                0 2px 8px rgba(0, 0, 0, 0.04);
  --fab-shadow-hover: 0 8px 24px rgba(0, 0, 0, 0.12),
                      0 4px 12px rgba(0, 0, 0, 0.08);
}

/* ==================== CONTAINER ==================== */
.fab-container {
  position: fixed;
  z-index: var(--fab-z-index);
  pointer-events: none;
}

/* Position Variants */
/* Bottom Center (Default) */
.fab-container:not([data-position]),
.fab-container[data-position="bottom-center"] {
  bottom: var(--fab-offset);
  left: 50%;
  transform: translateX(-50%);
}

.fab-container[data-position="bottom-right"] {
  bottom: var(--fab-offset);
  right: var(--fab-offset);
}

.fab-container[data-position="bottom-left"] {
  bottom: var(--fab-offset);
  left: var(--fab-offset);
}

.fab-container[data-position="top-center"] {
  top: var(--fab-offset);
  left: 50%;
  transform: translateX(-50%);
}

.fab-container[data-position="top-right"] {
  top: var(--fab-offset);
  right: var(--fab-offset);
}

.fab-container[data-position="top-left"] {
  top: var(--fab-offset);
  left: var(--fab-offset);
}

/* ==================== FAB ELEMENT (Main Wrapper) ==================== */
.fab {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  pointer-events: auto;

  /* Collapsed state */
  width: var(--fab-collapsed-size);
  height: var(--fab-collapsed-size);
  min-width: var(--fab-collapsed-size);

  /* Initial hidden state */
  opacity: 0;
  transform: translateY(24px) scale(0.85);

  /* Default expansion from center */
  transform-origin: center center;

  /* Performance */
  will-change: transform, opacity, width;
  backface-visibility: hidden;
  -webkit-font-smoothing: antialiased;
  perspective: 1000px;
}

/* Expansion Direction via Transform Origin */
/* Right alignment: icon on right, expand LEFT */
.fab-container[data-align="right"] .fab {
  transform-origin: right center;
}

/* Left alignment: icon on left, expand RIGHT */
.fab-container[data-align="left"] .fab {
  transform-origin: left center;
}

/* Center/default: expand from CENTER */
.fab-container[data-align="center"] .fab,
.fab-container:not([data-align]) .fab {
  transform-origin: center center;
}

/* ==================== VISIBILITY STATES (SIMPLIFIED 3-STAGE) ==================== */

/* Stage 1: Hidden - Entire button invisible */
.fab-container[data-state="hidden"] .fab {
  opacity: 0;
  transform: translateY(20px) scale(0.8);
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

/* Stage 2: Icon Visible - Bounce in, show icon/circle + halo */
.fab-container[data-state="icon-visible"] .fab {
  opacity: 1;
  transform: translateY(0) scale(1);
  width: var(--fab-collapsed-size);
  min-width: var(--fab-collapsed-size);
  animation: fabBounceIn var(--fab-appear-duration) var(--fab-spring-easing);
  transition: none; /* Disable transition during bounce */
}

/* Stage 3: Fully Visible - Text appears, button expands naturally */
.fab-container[data-state="fully-visible"] .fab {
  opacity: 1;
  transform: translateY(0) scale(1);
  width: auto;
  min-width: auto;
  max-width: none;
  transition: width 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94),
              min-width 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94),
              max-width 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* Scroll bounce effect */
.fab-container[data-bouncing="true"] .fab {
  animation: fabScrollBounce var(--fab-bounce-duration) cubic-bezier(0.68, -0.25, 0.265, 1.25);
}

/* ==================== KEYFRAME ANIMATIONS ==================== */

@keyframes fabBounceIn {
  0% {
    opacity: 0;
    transform: translateY(24px) scale(0.85);
  }
  50% {
    opacity: 1;
    transform: translateY(-5px) scale(1.03);
  }
  75% {
    transform: translateY(2px) scale(0.99);
  }
  90% {
    transform: translateY(-1px) scale(1.005);
  }
  100% {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes fabBounceOut {
  0% {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
  30% {
    opacity: 0.7;
    transform: translateY(4px) scale(0.97);
  }
  100% {
    opacity: 0;
    transform: translateY(24px) scale(0.85);
  }
}

@keyframes fabScrollBounce {
  0%, 100% {
    transform: translateY(0) scale(1);
  }
  25% {
    transform: translateY(-5px) scale(1.015);
  }
  50% {
    transform: translateY(1px) scale(0.995);
  }
  75% {
    transform: translateY(-1px) scale(1.005);
  }
}

/* ==================== HALO EFFECT (Background) ==================== */
.fab__halo {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);

  /* Always circular */
  width: calc(var(--fab-collapsed-size) * var(--fab-halo-scale));
  height: calc(var(--fab-collapsed-size) * var(--fab-halo-scale));
  border-radius: 50%;

  /* Radiant glow effect */
  background: radial-gradient(
    circle at center,
    rgba(var(--fab-halo-color), var(--fab-halo-opacity)) 0%,
    rgba(var(--fab-halo-color), calc(var(--fab-halo-opacity) * 0.5)) 40%,
    rgba(var(--fab-halo-color), 0) 70%
  );
  filter: blur(var(--fab-halo-blur));

  /* Initial state */
  opacity: 0;
  transform: translate(-50%, -50%) scale(0.5);

  /* Performance */
  will-change: transform, opacity;
  pointer-events: none;
  z-index: 0;
}

/* Halo animations for 3-stage states */
.fab-container[data-state="hidden"] .fab__halo {
  opacity: 0;
  transform: translate(-50%, -50%) scale(0.5);
}

.fab-container[data-state="icon-visible"] .fab__halo,
.fab-container[data-state="fully-visible"] .fab__halo {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
  animation: haloAppear var(--fab-appear-duration) cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* Pulse effect when bouncing */
.fab-container[data-bouncing="true"] .fab__halo {
  animation: haloPulse var(--fab-bounce-duration) cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes haloAppear {
  0% {
    opacity: 0;
    transform: translate(-50%, -50%) scale(0.5);
  }
  60% {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.1);
  }
  100% {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
  }
}

@keyframes haloPulse {
  0%, 100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
  }
  50% {
    transform: translate(-50%, -50%) scale(1.15);
    opacity: 0.8;
  }
}

/* ==================== CONTENT WRAPPER ==================== */
.fab__content {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  z-index: 1;

  background: var(--fab-bg-color);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-radius: var(--fab-border-radius);
  box-shadow: var(--fab-shadow);

  /* Transitions */
  transition:
    background-color 0.2s cubic-bezier(0.4, 0, 0.2, 1),
    box-shadow 0.2s cubic-bezier(0.4, 0, 0.2, 1),
    transform 0.15s cubic-bezier(0.4, 0, 0.2, 1);

  overflow: hidden;
}

/* Hover States */
.fab__content:hover {
  background: var(--fab-hover-bg);
  box-shadow: var(--fab-shadow-hover);
}

.fab__content:active {
  transform: scale(0.97);
}

/* ==================== BUTTON ELEMENT ==================== */
.fab__button,
.fab__link {
  all: unset;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;

  width: 100%;
  height: 100%;

  color: var(--fab-text-color);
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.01em;
  text-decoration: none;
  white-space: nowrap;

  cursor: pointer;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

/* Focus States */
.fab__button:focus-visible,
.fab__link:focus-visible {
  outline: 2px solid var(--fab-focus-ring);
  outline-offset: 2px;
  border-radius: var(--fab-border-radius);
}

/* ==================== ICON ==================== */
.fab__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;

  width: 20px;
  height: 20px;

  /* Always relative - use order to control visual centering */
  position: relative;

  /* Smooth transitions */
  transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.fab__icon svg {
  width: 100%;
  height: 100%;
  display: block;
}

/* Icon animation on hover (only when fully expanded) */
.fab-container[data-state="fully-visible"] .fab__button:hover .fab__icon,
.fab-container[data-state="fully-visible"] .fab__link:hover .fab__icon {
  transform: scale(1.08);
}

/* ==================== TEXT ==================== */
.fab__text {
  /* Hidden by default */
  opacity: 0;
  width: 0;
  max-width: 0;
  overflow: hidden;
  margin: 0;
  padding: 0;
  white-space: nowrap;
  flex-shrink: 0;
}

/* Stage 2 (icon-visible): Text still hidden */
.fab-container[data-state="icon-visible"] .fab__text {
  opacity: 0;
  width: 0;
  max-width: 0;
}

/* Stage 3 (fully-visible): Text appears and expands button */
.fab-container[data-state="fully-visible"] .fab__text {
  opacity: 1;
  width: auto;
  max-width: 15ch;
  transition:
    opacity 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94),
    width 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94),
    max-width 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* ==================== LAYOUT & ALIGNMENT (SIMPLIFIED) ==================== */

/* Base state: No padding for collapsed circular state */
.fab__button,
.fab__link {
  flex-direction: row;
  gap: 0;
  padding: 0;
  justify-content: center;
  transition: gap 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94),
              padding 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* Expanded state: Add padding for text */
.fab-container[data-state="fully-visible"] .fab__button,
.fab-container[data-state="fully-visible"] .fab__link {
  gap: 0.5rem;
  padding: 16px 32px;
}

/* Right alignment: Icon on right, text on left */
.fab-container[data-align="right"] .fab__button,
.fab-container[data-align="right"] .fab__link {
  flex-direction: row-reverse;
}

.fab-container[data-align="right"][data-state="fully-visible"] .fab__button,
.fab-container[data-align="right"][data-state="fully-visible"] .fab__link {
  padding: 16px 32px;
}

/* Left alignment: Icon on left, text on right */
.fab-container[data-align="left"] .fab__button,
.fab-container[data-align="left"] .fab__link {
  flex-direction: row;
}

.fab-container[data-align="left"][data-state="fully-visible"] .fab__button,
.fab-container[data-align="left"][data-state="fully-visible"] .fab__link {
  padding: 16px 32px;
}

/* Center alignment (default) */
.fab-container[data-align="center"][data-state="fully-visible"] .fab__button,
.fab-container[data-align="center"][data-state="fully-visible"] .fab__link,
.fab-container:not([data-align])[data-state="fully-visible"] .fab__button,
.fab-container:not([data-align])[data-state="fully-visible"] .fab__link {
  padding: 16px 32px;
}

/* ==================== TEXT-ONLY VARIANT ==================== */
/* Text-only buttons: No icon, just text that appears */
.fab__button:not(:has(.fab__icon)),
.fab__link:not(:has(.fab__icon)) {
  padding: 16px 32px;
}

.fab-container[data-state="icon-visible"] .fab__button:not(:has(.fab__icon)) .fab__text,
.fab-container[data-state="icon-visible"] .fab__link:not(:has(.fab__icon)) .fab__text {
  opacity: 0;
  width: 0;
}

.fab-container[data-state="fully-visible"] .fab__button:not(:has(.fab__icon)) .fab__text,
.fab-container[data-state="fully-visible"] .fab__link:not(:has(.fab__icon)) .fab__text {
  opacity: 1;
  width: auto;
}

/* ==================== PAGINATION VARIANT ==================== */
.fab__pagination {
  gap: 0.75rem;
  padding: 0 1rem;
}

.fab__page-btn {
  all: unset;
  display: inline-flex;
  align-items: center;
  justify-content: center;

  width: 32px;
  height: 32px;
  border-radius: 50%;

  cursor: pointer;
  transition: background-color 0.2s ease;
}

.fab__page-btn:hover {
  background: rgba(255, 255, 255, 0.1);
}

.fab__page-btn:focus-visible {
  outline: 2px solid var(--fab-focus-ring);
  outline-offset: 1px;
}

.fab__page-number {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--fab-text-color);
  min-width: 40px;
  text-align: center;
}

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

/* Tablet */
@media (max-width: 1024px) {
  :root {
    --fab-offset: 1.5rem;
  }
}

/* Mobile */
@media (max-width: 768px) {
  :root {
    --fab-offset: 1.25rem;
    --fab-collapsed-size: 40px;
    --fab-expanded-min-width: 120px;
    --fab-border-radius: 20px;
    /* Faster, smoother animations on mobile */
    --fab-appear-duration: 0.4s;
    --fab-expand-duration: 0.3s;
    --fab-bounce-duration: 0.2s;
  }

  /* Full-width variant on mobile */
  .fab-container[data-mobile="full-width"][data-state="fully-visible"] .fab {
    width: calc(100vw - 2 * var(--fab-offset)) !important;
    max-width: calc(100vw - 2 * var(--fab-offset)) !important;
  }

  .fab-container[data-mobile="full-width"] {
    left: var(--fab-offset);
    right: var(--fab-offset);
    transform: none;
  }

  .fab__button,
  .fab__link {
    font-size: 0.875rem;
  }

  .fab__icon {
    width: 18px;
    height: 18px;
  }

  /* Mobile expanded state - add gap and padding */
  .fab-container[data-state="fully-visible"] .fab__button,
  .fab-container[data-state="fully-visible"] .fab__link {
    gap: 0.4rem;
    padding: 12px 24px;
  }


  /* Mobile text transitions - slightly faster than desktop */
  .fab-container[data-state="fully-visible"] .fab__text {
    transition:
      opacity 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94),
      width 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94),
      max-width 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  }

  /* GPU acceleration for smoother mobile */
  .fab,
  .fab__halo,
  .fab__content {
    transform: translateZ(0);
    will-change: transform, opacity;
  }
}

/* Small mobile */
@media (max-width: 480px) {
  :root {
    --fab-offset: 1rem;
    --fab-collapsed-size: 38px;
    --fab-expanded-min-width: 100px;
    --fab-border-radius: 19px;
  }

  .fab__button,
  .fab__link {
    font-size: 0.8125rem;
  }

  .fab__icon {
    width: 16px;
    height: 16px;
  }

  .fab__text {
    max-width: 12ch;
  }

  .fab-container[data-state="fully-visible"] .fab__button,
  .fab-container[data-state="fully-visible"] .fab__link {
    gap: 0.4rem;
    padding: 10px 20px;
  }
}

/* ==================== REDUCED MOTION ==================== */
@media (prefers-reduced-motion: reduce) {
  :root {
    --fab-appear-duration: 0.2s;
    --fab-expand-duration: 0.2s;
    --fab-bounce-duration: 0.1s;
  }

  /* Disable bounce animations */
  .fab-container[data-state="icon-visible"] .fab,
  .fab-container[data-bouncing="true"] .fab {
    animation: none !important;
  }

  .fab-container[data-state="icon-visible"] .fab,
  .fab-container[data-state="fully-visible"] .fab {
    opacity: 1;
    transform: none;
  }

  .fab-container[data-state="hidden"] .fab {
    opacity: 0;
    transform: none;
  }

  .fab__halo {
    animation: none !important;
  }
}

/* ==================== DARK MODE SUPPORT ==================== */
@media (prefers-color-scheme: dark) {
  :root {
    --fab-bg-color: #1f1f1f;
    --fab-hover-bg: #2a2a2a;
  }
}

/* ==================== HIGH CONTRAST MODE ==================== */
@media (prefers-contrast: high) {
  .fab__content {
    border: 2px solid var(--fab-text-color);
  }

  .fab__button:focus-visible,
  .fab__link:focus-visible {
    outline-width: 3px;
  }
}

/* ==================== PRINT STYLES ==================== */
@media print {
  .fab-container {
    display: none !important;
  }
}