/* ============================================
   ARTH Button Components
   ============================================ */

/* ===================
   Base Button
   =================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    font-family: var(--font-family-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    line-height: 1;
    text-decoration: none;
    border-radius: var(--radius-lg);
    border: 1px solid transparent;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: all var(--transition-fast) var(--ease-default);
    white-space: nowrap;
    user-select: none;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    pointer-events: none;
}

.btn svg {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

/* ===================
   Button Sizes
   =================== */

.btn-xs {
    padding: var(--space-1) var(--space-2);
    font-size: var(--font-size-xs);
    border-radius: var(--radius-md);
}

.btn-xs svg {
    width: 14px;
    height: 14px;
}

.btn-sm {
    padding: var(--space-2) var(--space-3);
    font-size: var(--font-size-sm);
}

.btn-sm svg {
    width: 16px;
    height: 16px;
}

.btn-lg {
    padding: var(--space-4) var(--space-6);
    font-size: var(--font-size-base);
}

.btn-lg svg {
    width: 20px;
    height: 20px;
}

.btn-xl {
    padding: var(--space-5) var(--space-8);
    font-size: var(--font-size-lg);
    border-radius: var(--radius-xl);
}

/* ===================
   Primary Button
   =================== */

.btn-primary {
    background: var(--gradient-primary);
    color: var(--color-text-inverse);
    border-color: transparent;
    box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
    box-shadow: var(--shadow-primary);
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
    box-shadow: var(--shadow-xs);
}

/* ===================
   Accent Button (Gold)
   =================== */

.btn-accent {
    background: var(--gradient-accent);
    color: var(--color-primary-900);
    border-color: transparent;
    box-shadow: var(--shadow-sm);
}

.btn-accent:hover {
    box-shadow: var(--shadow-accent);
    transform: translateY(-1px);
}

/* ===================
   Secondary Button
   =================== */

.btn-secondary {
    background: var(--color-surface-card);
    color: var(--color-text-primary);
    border-color: var(--color-border-medium);
}

.btn-secondary:hover {
    background: var(--color-surface-page);
    border-color: var(--color-border-dark);
}

/* ===================
   Ghost Button
   =================== */

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
    border-color: transparent;
}

.btn-ghost:hover {
    background: var(--color-surface-page);
    color: var(--color-text-primary);
}

/* ===================
   Outline Variants
   =================== */

.btn-outline-primary {
    background: transparent;
    color: var(--color-primary-600);
    border-color: var(--color-primary-600);
}

.btn-outline-primary:hover {
    background: var(--color-primary-600);
    color: var(--color-text-inverse);
}

.btn-outline-accent {
    background: transparent;
    color: var(--color-accent-500);
    border-color: var(--color-accent-500);
}

.btn-outline-accent:hover {
    background: var(--color-accent-500);
    color: var(--color-primary-900);
}

/* ===================
   Semantic Buttons
   =================== */

.btn-success {
    background: var(--gradient-success);
    color: white;
}

.btn-success:hover {
    box-shadow: var(--shadow-success);
    transform: translateY(-1px);
}

.btn-warning {
    background: var(--gradient-warning);
    color: var(--color-primary-900);
}

.btn-warning:hover {
    box-shadow: var(--shadow-warning);
    transform: translateY(-1px);
}

.btn-danger {
    background: var(--gradient-danger);
    color: white;
}

.btn-danger:hover {
    box-shadow: var(--shadow-danger);
    transform: translateY(-1px);
}

/* ===================
   Icon Button
   =================== */

.btn-icon {
    width: 40px;
    height: 40px;
    padding: 0;
    border-radius: var(--radius-lg);
}

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

.btn-icon.btn-lg {
    width: 48px;
    height: 48px;
}

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

/* ===================
   Full Width
   =================== */

.btn-block {
    width: 100%;
}

/* ===================
   Ripple Effect
   =================== */

.btn-ripple {
    position: relative;
    overflow: hidden;
}

.btn-ripple .ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: scale(0);
    animation: ripple 0.6s linear;
    pointer-events: none;
}

/* ===================
   Loading State
   =================== */

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

.btn-loading::after {
    content: '';
    position: absolute;
    width: 18px;
    height: 18px;
    top: 50%;
    left: 50%;
    margin: -9px 0 0 -9px;
    border: 2px solid currentColor;
    border-radius: 50%;
    border-right-color: transparent;
    animation: spin 0.6s linear infinite;
}

.btn-loading.btn-primary::after,
.btn-loading.btn-accent::after,
.btn-loading.btn-success::after,
.btn-loading.btn-danger::after {
    border-color: white;
    border-right-color: transparent;
}

/* ===================
   Button Group
   =================== */

.btn-group {
    display: inline-flex;
    vertical-align: middle;
}

.btn-group .btn {
    border-radius: 0;
    margin-left: -1px;
}

.btn-group .btn:first-child {
    margin-left: 0;
    border-radius: var(--radius-lg) 0 0 var(--radius-lg);
}

.btn-group .btn:last-child {
    border-radius: 0 var(--radius-lg) var(--radius-lg) 0;
}

.btn-group .btn:not(:first-child):not(:last-child) {
    border-radius: 0;
}

.btn-group .btn:hover,
.btn-group .btn:focus {
    z-index: 1;
}

/* ===================
   Toggle Button
   =================== */

.btn-toggle {
    position: relative;
}

.btn-toggle.active {
    background: var(--color-primary-600);
    color: var(--color-text-inverse);
    border-color: var(--color-primary-600);
}

/* ===================
   Link Button
   =================== */

.btn-link {
    background: transparent;
    border-color: transparent;
    color: var(--color-text-link);
    padding-left: 0;
    padding-right: 0;
}

.btn-link:hover {
    color: var(--color-text-link-hover);
    text-decoration: underline;
}