/* Button Components */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    border: 1px solid transparent;
    border-radius: var(--border-radius);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
    line-height: 1.5;
    min-height: 2.5rem;
    white-space: nowrap;
}

.btn:focus {
    outline: 2px solid transparent;
    outline-offset: 2px;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

/* Button variants */
.btn-primary {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.btn-primary:hover {
    background-color: #1d4ed8;
    border-color: #1d4ed8;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.4);
    text-decoration: none;
    color: white;
}

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

.btn-secondary:hover {
    background-color: var(--bg-secondary);
    border-color: #d1d5db;
    transform: translateY(-1px);
    text-decoration: none;
    color: var(--text-primary);
}

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

.btn-success:hover {
    background-color: #059669;
    border-color: #059669;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
    text-decoration: none;
    color: white;
}

.btn-error {
    background-color: var(--error-color);
    color: white;
    border-color: var(--error-color);
}

.btn-error:hover {
    background-color: #dc2626;
    border-color: #dc2626;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
    text-decoration: none;
    color: white;
}

.btn-warning {
    background-color: var(--warning-color);
    color: white;
    border-color: var(--warning-color);
}

.btn-warning:hover {
    background-color: #d97706;
    border-color: #d97706;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(245, 158, 11, 0.4);
    text-decoration: none;
    color: white;
}

/* Button sizes */
.btn-sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: var(--font-size-sm);
    min-height: 2rem;
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-lg);
    min-height: 3rem;
}

.btn-xl {
    padding: var(--spacing-lg) 2rem;
    font-size: var(--font-size-xl);
    min-height: 3.5rem;
}

/* Button modifiers */
.btn-full {
    width: 100%;
}

.btn-outline {
    background-color: transparent;
}

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

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

.btn-outline.btn-secondary {
    color: var(--text-secondary);
    border-color: var(--border-color);
}

.btn-outline.btn-secondary:hover {
    background-color: var(--text-secondary);
    color: white;
    border-color: var(--text-secondary);
}

/* Button groups */
.btn-group {
    display: inline-flex;
    border-radius: var(--border-radius);
    overflow: hidden;
}

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

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

.btn-group .btn:last-child {
    border-top-right-radius: var(--border-radius);
    border-bottom-right-radius: var(--border-radius);
}

.btn-group .btn:hover {
    z-index: 1;
    transform: none;
}

/* Loading state */
.btn-loading {
    position: relative;
    pointer-events: none;
}

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

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

/* Responsive adjustments */
@media (max-width: 640px) {
    .btn {
        padding: var(--spacing-xs) var(--spacing-md);
        font-size: var(--font-size-sm);
        min-height: 2.25rem;
    }
    
    .btn-lg {
        padding: var(--spacing-sm) var(--spacing-lg);
        font-size: var(--font-size-base);
        min-height: 2.75rem;
    }
    
    .btn-group {
        flex-direction: column;
        width: 100%;
    }
    
    .btn-group .btn {
        border-radius: 0;
        margin-left: 0;
        margin-top: -1px;
    }
    
    .btn-group .btn:first-child {
        border-radius: var(--border-radius) var(--border-radius) 0 0;
        margin-top: 0;
    }
    
    .btn-group .btn:last-child {
        border-radius: 0 0 var(--border-radius) var(--border-radius);
    }
}