/*
 * Modern Button and Link Styles
 * Contemporary button and link designs with gradients, animations, and accessibility
 * Requirements: 3.2, 4.2, 4.3, 5.2
 */

/* ===== MODERN BUTTON STYLES ===== */

/* Base Button Styles */
.btn {
  /* Layout and Positioning */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  
  /* Typography */
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  line-height: var(--line-height-tight);
  text-decoration: none;
  text-align: center;
  white-space: nowrap;
  
  /* Spacing and Sizing */
  padding: var(--space-3) var(--space-6);
  min-height: 44px; /* Touch-friendly minimum size */
  min-width: 44px;
  
  /* Visual Design */
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  background: var(--color-primary-gradient);
  color: var(--color-white);
  box-shadow: var(--shadow-sm);
  
  /* Transitions and Animations */
  transition: all var(--duration-normal) var(--ease-out);
  cursor: pointer;
  user-select: none;
  
  /* Prevent text selection and improve touch */
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
}

/* Button Hover States */
.btn:hover {
  background: var(--color-primary-gradient-hover);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* Button Focus States - Accessibility */
.btn:focus {
  outline: none;
  box-shadow: var(--shadow-md), 0 0 0 3px rgba(108, 92, 231, 0.3);
  transform: translateY(-1px);
}

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

/* Button Active States */
.btn:active {
  transform: translateY(0);
  box-shadow: var(--shadow-sm);
}

/* Button Disabled States */
.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
  box-shadow: var(--shadow-xs);
  pointer-events: none;
}

/* ===== BUTTON VARIANTS ===== */

/* Primary Button (Default) */
.btn-primary {
  background: var(--color-primary-gradient);
  color: var(--color-white);
  border-color: transparent;
}

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

/* Secondary Button */
.btn-secondary {
  background: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-secondary-light) 100%);
  color: var(--color-white);
  border-color: transparent;
}

.btn-secondary:hover {
  background: linear-gradient(135deg, var(--color-secondary-dark) 0%, var(--color-secondary) 100%);
}

/* Outline Button */
.btn-outline {
  background: rgba(108, 92, 231, 0.1);
  color: var(--color-primary);
  border-color: var(--color-primary);
  border-width: 2px;
  backdrop-filter: var(--glass-backdrop-filter);
  font-weight: var(--font-weight-semibold);
  box-shadow: 0 4px 12px rgba(108, 92, 231, 0.15);
}

.btn-outline:hover {
  background: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
  box-shadow: 0 6px 16px rgba(108, 92, 231, 0.25);
  transform: translateY(-3px);
}

/* Ghost Button */
.btn-ghost {
  background: transparent;
  color: var(--color-text-primary);
  border-color: transparent;
  box-shadow: none;
}

.btn-ghost:hover {
  background: var(--glass-bg-light);
  color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

/* Accent Button */
.btn-accent {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-light) 100%);
  color: var(--color-white);
  border-color: transparent;
}

.btn-accent:hover {
  background: linear-gradient(135deg, var(--color-accent-dark) 0%, var(--color-accent) 100%);
}

/* ===== BUTTON SIZES ===== */

/* Small Button */
.btn-sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-sm);
  min-height: 36px;
  min-width: 36px;
}

/* Large Button */
.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--font-size-lg);
  min-height: 52px;
  min-width: 52px;
}

/* Extra Large Button */
.btn-xl {
  padding: var(--space-5) var(--space-10);
  font-size: var(--font-size-xl);
  min-height: 60px;
  min-width: 60px;
}

/* ===== BUTTON GROUPS ===== */

.btn-group {
  display: inline-flex;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.btn-group .btn {
  border-radius: 0;
  border-right: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-group .btn:first-child {
  border-top-left-radius: var(--radius-lg);
  border-bottom-left-radius: var(--radius-lg);
}

.btn-group .btn:last-child {
  border-top-right-radius: var(--radius-lg);
  border-bottom-right-radius: var(--radius-lg);
  border-right: none;
}

/* ===== MODERN LINK STYLES ===== */

/* Base Link Styles */
.link {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
  position: relative;
  transition: all var(--duration-normal) var(--ease-out);
  cursor: pointer;
}

/* Link Hover Effects */
.link:hover {
  color: var(--color-primary-dark);
}

/* Underline Animation */
.link-underline {
  position: relative;
}

.link-underline::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary-gradient);
  transition: width var(--duration-normal) var(--ease-out);
}

.link-underline:hover::after {
  width: 100%;
}

/* Gradient Link */
.link-gradient {
  background: var(--color-primary-gradient);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-size: 200% 100%;
  transition: background-position var(--duration-normal) var(--ease-out);
}

.link-gradient:hover {
  background-position: 100% 0;
}

/* External Link Indicator */
.link-external {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
}

.link-external::after {
  content: '↗';
  font-size: 0.8em;
  opacity: 0.7;
  transition: opacity var(--duration-fast) var(--ease-out);
}

.link-external:hover::after {
  opacity: 1;
}

/* Link Focus States - Accessibility */
.link:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.link:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* ===== ICON BUTTONS ===== */

.btn-icon {
  padding: var(--space-3);
  min-width: 44px;
  min-height: 44px;
  border-radius: var(--radius-full);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-icon-sm {
  padding: var(--space-2);
  min-width: 36px;
  min-height: 36px;
}

.btn-icon-lg {
  padding: var(--space-4);
  min-width: 52px;
  min-height: 52px;
}

/* ===== FLOATING ACTION BUTTON ===== */

.btn-fab {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  background: var(--color-primary-gradient);
  color: var(--color-white);
  border: none;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--duration-normal) var(--ease-out);
  z-index: var(--z-fixed);
}

.btn-fab:hover {
  transform: scale(1.1);
  box-shadow: var(--shadow-xl);
}

.btn-fab:active {
  transform: scale(0.95);
}

/* ===== LOADING STATES ===== */

.btn-loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}

.btn-loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 20px;
  height: 20px;
  margin: -10px 0 0 -10px;
  border: 2px solid transparent;
  border-top: 2px solid currentColor;
  border-radius: 50%;
  animation: btn-spin 1s linear infinite;
}

@keyframes btn-spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

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

@media (max-width: 768px) {
  .btn {
    padding: var(--space-3) var(--space-5);
    font-size: var(--font-size-sm);
  }
  
  .btn-lg {
    padding: var(--space-4) var(--space-6);
    font-size: var(--font-size-base);
  }
  
  .btn-fab {
    bottom: var(--space-4);
    right: var(--space-4);
    width: 48px;
    height: 48px;
  }
}



/* ===== ACCESSIBILITY ENHANCEMENTS ===== */

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
  .btn,
  .link,
  .btn-fab {
    transition: none;
    animation: none;
  }
  
  .btn:hover,
  .btn:focus {
    transform: none;
  }
  
  .btn-fab:hover {
    transform: none;
  }
  
  .link-underline::after {
    transition: none;
  }
  
  .btn-loading::after {
    animation: none;
  }
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
  .btn {
    border: 2px solid;
  }
  
  .btn-outline {
    border-width: 3px;
  }
  
  .link {
    text-decoration: underline;
  }
}

/* Print Styles */
@media print {
  .btn,
  .btn-fab {
    background: none !important;
    color: black !important;
    border: 1px solid black !important;
    box-shadow: none !important;
  }
  
  .link {
    color: black !important;
    text-decoration: underline !important;
  }
}

/* ===== UTILITY CLASSES ===== */

.btn-block {
  display: flex;
  width: 100%;
}

.btn-rounded {
  border-radius: var(--radius-full);
}

.btn-square {
  border-radius: 0;
}

.btn-no-shadow {
  box-shadow: none;
}

.btn-no-shadow:hover {
  box-shadow: none;
}

/* Link Utilities */
.link-muted {
  color: var(--color-text-secondary);
}

.link-muted:hover {
  color: var(--color-text-primary);
}

.link-no-underline {
  text-decoration: none;
}

.link-no-underline:hover {
  text-decoration: none;
}