/* ========================================
   Buttons Component
   共通のボタンスタイル - Modern & Stylish
   ======================================== */

/* ========== Base Button ========== */
.btn {
  /* Layout */
  display: inline-flex;
  align-items: center;
  justify-content: center;

  /* Spacing */
  padding: var(--spacing-sm) var(--spacing-md);
  gap: var(--spacing-xs);

  /* Typography */
  font-family: inherit;
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.2;
  text-decoration: none !important;
  white-space: nowrap;
  letter-spacing: 0.01em;

  /* Appearance */
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  min-height: var(--button-height-md);
  cursor: pointer;

  /* Transition */
  transition: all var(--duration-200) var(--ease-in-out);

  /* Interaction */
  user-select: none;
  -webkit-tap-highlight-color: transparent;

  /* Modern touch */
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0) 100%);
  opacity: 0;
  transition: opacity var(--duration-200) var(--ease-in-out);
  pointer-events: none;
}

.btn:hover::before {
  opacity: 1;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
  filter: grayscale(0.3);
}

.btn:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
  box-shadow: 0 0 0 4px rgba(var(--primary-rgb), 0.1);
}

/* ========== Size Variants ========== */
.btn--sm {
  min-height: var(--button-height-sm);
  padding: var(--spacing-xs) var(--spacing-md);
  font-size: 0.875rem;
}

.btn--lg {
  min-height: var(--button-height-lg);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1.125rem;
  font-weight: 600;
}

/* ========== Icon Buttons ========== */
.btn-icon {
  width: 36px;
  height: 36px;
  min-height: 36px;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-color);
  background: var(--bg-primary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  color: var(--text-secondary);
}

.btn-icon:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.btn-icon--sm {
  width: 32px;
  height: 32px;
  min-height: 32px;
}

.btn-icon.btn-info-icon {
  background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
  border-color: #93c5fd;
  color: #1e40af;
}

.btn-icon.btn-info-icon:hover {
  background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%);
  border-color: #60a5fa;
  color: #1e3a8a;
}

.btn-icon.btn-danger-icon {
  background: linear-gradient(135deg, #fef2f2 0%, #fee2e2 100%);
  border-color: #fca5a5;
  color: #991b1b;
}

.btn-icon.btn-danger-icon:hover {
  background: linear-gradient(135deg, #fee2e2 0%, #fecaca 100%);
  border-color: #f87171;
  color: #7f1d1d;
}

.btn-icon.btn-success-icon {
  background: linear-gradient(135deg, #ecfdf5 0%, #d1fae5 100%);
  border-color: #6ee7b7;
  color: #065f46;
}

.btn-icon.btn-success-icon:hover {
  background: linear-gradient(135deg, #d1fae5 0%, #a7f3d0 100%);
  border-color: #34d399;
  color: #064e3b;
}

/* ========== Color Variants ========== */

/* Primary */
.btn-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  border-color: var(--primary-color);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(var(--primary-rgb), 0.25);
}

.btn-primary:hover:not(:disabled) {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-color) 100%);
  border-color: var(--primary-dark);
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(var(--primary-rgb), 0.35);
}

.btn-primary:active:not(:disabled) {
  transform: translateY(0);
  box-shadow: 0 2px 8px rgba(var(--primary-rgb), 0.25);
}

/* Success */
.btn-success {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  border-color: var(--success-color);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(16, 185, 129, 0.25);
}

.btn-success:hover:not(:disabled) {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  border-color: #059669;
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(16, 185, 129, 0.35);
}

/* Danger */
.btn-danger {
  background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
  border-color: var(--danger-color);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(239, 68, 68, 0.25);
}

.btn-danger:hover:not(:disabled) {
  background: linear-gradient(135deg, #dc2626 0%, #b91c1c 100%);
  border-color: #dc2626;
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(239, 68, 68, 0.35);
}

/* Warning */
.btn-warning {
  background: #f1ba5d;
  border-color: var(--warning-color);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(245, 158, 11, 0.25);
}

.btn-warning:hover:not(:disabled) {
  background: linear-gradient(135deg, #d97706 0%, #cf8043 100%);
  border-color: #d97706;
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(245, 158, 11, 0.35);
}

/* Info */
.btn-info {
  background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
  border-color: var(--info-color);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.25);
}

.btn-info:hover:not(:disabled) {
  background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
  border-color: #2563eb;
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.35);
}

/* Secondary */
.btn-secondary {
  background: linear-gradient(135deg, #6b7280 0%, #4b5563 100%);
  border-color: var(--gray-600);
  color: var(--text-inverse);
  box-shadow: 0 2px 8px rgba(107, 114, 128, 0.25);
}

.btn-secondary:hover:not(:disabled) {
  background: linear-gradient(135deg, #4b5563 0%, #374151 100%);
  border-color: var(--gray-700);
  color: var(--text-inverse);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(107, 114, 128, 0.35);
}

/* ========== Outline Variants ========== */
.btn-outline-primary {
  background-color: transparent;
  border-color: var(--primary-color);
  color: var(--primary-color);
  position: relative;
}

.btn-outline-primary::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--primary-color);
  opacity: 0;
  transition: opacity var(--duration-200) var(--ease-in-out);
  border-radius: inherit;
  z-index: -1;
}

.btn-outline-primary:hover:not(:disabled) {
  border-color: var(--primary-color);
  color: var(--text-inverse);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(var(--primary-rgb), 0.2);
}

.btn-outline-primary:hover:not(:disabled)::after {
  opacity: 1;
}

.btn-outline-danger {
  background-color: transparent;
  border-color: var(--danger-color);
  color: var(--danger-color);
  position: relative;
}

.btn-outline-danger::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--danger-color);
  opacity: 0;
  transition: opacity var(--duration-200) var(--ease-in-out);
  border-radius: inherit;
  z-index: -1;
}

.btn-outline-danger:hover:not(:disabled) {
  border-color: var(--danger-color);
  color: var(--text-inverse);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(239, 68, 68, 0.2);
}

.btn-outline-danger:hover:not(:disabled)::after {
  opacity: 1;
}

/* ========== Style Variants ========== */

/* Action Icon Button (Circular) */
.btn-action-icon {
  width: 40px;
  height: 40px;
  min-height: 40px;
  padding: 0;
  border-radius: 50%;
  background: linear-gradient(135deg, #ffffff 0%, #f9fafb 100%);
  border: 1px solid rgba(var(--primary-rgb), 0.15);
  color: var(--text-light);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-action-icon:hover:not(:disabled) {
  background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
  border-color: rgba(var(--primary-rgb), 0.3);
}

/* Floating Action Button */
.btn-floating {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 56px;
  height: 56px;
  min-height: 56px;
  padding: 0;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  box-shadow: 0 4px 16px rgba(var(--primary-rgb), 0.4);
  z-index: var(--z-sticky);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-floating:hover:not(:disabled) {
  transform: scale(1.1) rotate(90deg);
  box-shadow: 0 8px 24px rgba(var(--primary-rgb), 0.5);
}

/* ========== Loading State ========== */
.btn--loading {
  position: relative;
  color: transparent !important;
  pointer-events: none;
}

.btn--loading::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  border: 2.5px solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: btn-spin 0.6s linear infinite;
  color: var(--text-inverse);
}

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

/* ========== Button Groups ========== */
.btn-group {
  display: inline-flex;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
}

.btn-group--vertical {
  flex-direction: column;
}

.btn-group--stretch .btn {
  flex: 1;
}

.btn-group--connected {
  gap: 0;
}

.btn-group--connected .btn:not(:first-child) {
  border-top-left-radius: 0;
  border-bottom-left-radius: 0;
  margin-left: -1px;
}

.btn-group--connected .btn:not(:last-child) {
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

/* ========== Responsive ========== */
@media (max-width: 767.98px) {
  .btn {
    font-size: 0.875rem;
  }

  /* モバイルではタッチ対象を大きく */
  .btn:not(.btn--sm) {
    min-height: var(--touch-target-min);
  }

  /* モバイル用全幅ボタン */
  .btn--mobile-full {
    width: 100%;
  }

  .btn-floating {
    bottom: 16px;
    right: 16px;
    width: 48px;
    height: 48px;
    min-height: 48px;
  }
}

/* ========== Touch Devices ========== */
@media (hover: none) {
  .btn:active:not(:disabled) {
    transform: scale(0.96);
  }

  /* タップ時の視覚的フィードバック */
  .btn:active:not(:disabled)::before {
    content: "";
    position: absolute;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.08);
    border-radius: inherit;
  }
}

/* ========== Accessibility ========== */
@media (prefers-reduced-motion: reduce) {
  .btn,
  .btn::before,
  .btn::after {
    transition: none;
    animation: none;
  }
}

/* ========== Dark Mode Support ========== */
@media (prefers-color-scheme: dark) {
  .btn-icon {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.1);
  }

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

  .btn-action-icon {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.05) 100%);
    border-color: rgba(255, 255, 255, 0.15);
  }
}

/* ========== Print ========== */
@media print {
  .btn {
    border: 1px solid var(--gray-800);
    box-shadow: none;
    background: white !important;
    color: black !important;
  }

  .btn:hover {
    transform: none;
  }

  .btn-floating {
    display: none;
  }
}

/* ========== Dark Mode Support ========== */
@media (prefers-color-scheme: dark) {
  .btn-icon {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.1);
  }

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

  .btn-action-icon {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.05) 100%);
    border-color: rgba(255, 255, 255, 0.15);
  }
}

/* ========== Dark Mode Support ========== */
@media (prefers-color-scheme: dark) {
  .btn-icon {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.1);
  }

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

  .btn-action-icon {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.05) 100%);
    border-color: rgba(255, 255, 255, 0.15);
  }
}

/* ========== Dark Mode Support ========== */
@media (prefers-color-scheme: dark) {
  .btn-icon {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.1);
  }

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

  .btn-action-icon {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.05) 100%);
    border-color: rgba(255, 255, 255, 0.15);
  }
}

/* ========== Dark Mode Class Support ========== */
.dark-mode .btn,
[data-theme="dark"] .btn {
  color: var(--dm-foreground);
}

.dark-mode .btn-primary,
[data-theme="dark"] .btn-primary {
  background: linear-gradient(135deg, var(--dm-primary), #2563eb);
  border-color: var(--dm-primary);
  color: white;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.dark-mode .btn-primary:hover:not(:disabled),
[data-theme="dark"] .btn-primary:hover:not(:disabled) {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  border-color: #2563eb;
  color: white;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.dark-mode .btn-success,
[data-theme="dark"] .btn-success {
  background: linear-gradient(135deg, var(--dm-success), #059669);
  border-color: var(--dm-success);
  box-shadow: 0 2px 8px rgba(16, 185, 129, 0.3);
}

.dark-mode .btn-success:hover:not(:disabled),
[data-theme="dark"] .btn-success:hover:not(:disabled) {
  background: linear-gradient(135deg, #059669, #047857);
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
}

.dark-mode .btn-danger,
[data-theme="dark"] .btn-danger {
  background: linear-gradient(135deg, var(--dm-destructive), #dc2626);
  border-color: var(--dm-destructive);
  box-shadow: 0 2px 8px rgba(239, 68, 68, 0.3);
}

.dark-mode .btn-danger:hover:not(:disabled),
[data-theme="dark"] .btn-danger:hover:not(:disabled) {
  background: linear-gradient(135deg, #dc2626, #b91c1c);
  box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
}

.dark-mode .btn-info,
[data-theme="dark"] .btn-info {
  background: linear-gradient(135deg, var(--dm-info), #2563eb);
  border-color: var(--dm-info);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.dark-mode .btn-info:hover:not(:disabled),
[data-theme="dark"] .btn-info:hover:not(:disabled) {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.dark-mode .btn-warning,
[data-theme="dark"] .btn-warning {
  background: linear-gradient(135deg, var(--dm-accent), #a79076);
  border-color: var(--dm-accent);
  box-shadow: 0 2px 8px rgba(245, 158, 11, 0.3);
}

.dark-mode .btn-warning:hover:not(:disabled),
[data-theme="dark"] .btn-warning:hover:not(:disabled) {
  background: linear-gradient(135deg, #d8892e, #c96e28);
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.4);
}

.dark-mode .btn-secondary,
[data-theme="dark"] .btn-secondary {
  background: linear-gradient(135deg, #6b7280 0%, #4b5563 100%);
  border-color: var(--dm-muted);
}

.dark-mode .btn-secondary:hover:not(:disabled),
[data-theme="dark"] .btn-secondary:hover:not(:disabled) {
  background: linear-gradient(135deg, #4b5563 0%, #374151 100%);
}

/* Outline variants */
.dark-mode .btn-outline-primary,
[data-theme="dark"] .btn-outline-primary {
  background-color: transparent;
  border-color: var(--dm-primary);
  color: var(--dm-primary);
}

.dark-mode .btn-outline-primary:hover:not(:disabled),
[data-theme="dark"] .btn-outline-primary:hover:not(:disabled) {
  background-color: rgba(59, 130, 246, 0.1);
  border-color: var(--dm-primary);
  color: var(--dm-primary);
}

.dark-mode .btn-outline-secondary,
[data-theme="dark"] .btn-outline-secondary {
  background-color: transparent;
  border-color: var(--dm-border);
  color: var(--dm-foreground);
}

.dark-mode .btn-outline-secondary:hover:not(:disabled),
[data-theme="dark"] .btn-outline-secondary:hover:not(:disabled) {
  background-color: rgba(71, 85, 105, 0.3);
  border-color: var(--dm-muted);
  color: var(--dm-foreground);
}

.dark-mode .btn-outline-danger,
[data-theme="dark"] .btn-outline-danger {
  background-color: transparent;
  border-color: var(--dm-destructive);
  color: var(--dm-destructive);
}

.dark-mode .btn-outline-danger:hover:not(:disabled),
[data-theme="dark"] .btn-outline-danger:hover:not(:disabled) {
  background-color: rgba(239, 68, 68, 0.1);
  border-color: var(--dm-destructive);
  color: var(--dm-destructive);
}

.dark-mode .btn-outline-success,
[data-theme="dark"] .btn-outline-success {
  background-color: transparent;
  border-color: var(--dm-success);
  color: var(--dm-success);
}

.dark-mode .btn-outline-success:hover:not(:disabled),
[data-theme="dark"] .btn-outline-success:hover:not(:disabled) {
  background-color: rgba(16, 185, 129, 0.1);
  border-color: var(--dm-success);
  color: var(--dm-success);
}

.dark-mode .btn-outline-warning,
[data-theme="dark"] .btn-outline-warning {
  background-color: transparent;
  border-color: var(--dm-accent);
  color: var(--dm-accent);
}

.dark-mode .btn-outline-warning:hover:not(:disabled),
[data-theme="dark"] .btn-outline-warning:hover:not(:disabled) {
  background-color: rgba(245, 158, 11, 0.1);
  border-color: var(--dm-accent);
  color: var(--dm-accent);
}

.dark-mode .btn-icon,
[data-theme="dark"] .btn-icon {
  background: rgba(71, 85, 105, 0.3);
  border-color: var(--dm-border);
  color: var(--dm-muted-foreground);
}

.dark-mode .btn-icon:hover,
[data-theme="dark"] .btn-icon:hover {
  background: rgba(71, 85, 105, 0.5);
  color: var(--dm-foreground);
}

/* ========== Print ========== */