/* ===================================
   Unified Button System
   Consistent button styles across all components
   =================================== */

:root {
    /* Button Padding System */
    --button-padding-xs: 8px 16px;
    --button-padding-sm: 12px 24px;
    --button-padding-md: 16px 32px;
    --button-padding-lg: 20px 40px;
    --button-padding-xl: 24px 48px;
    
    /* Button Heights (including padding and border) */
    --button-height-xs: 32px;
    --button-height-sm: 36px;
    --button-height-md: 44px;
    --button-height-lg: 52px;
    --button-height-xl: 60px;
    
    /* Button Font Sizes */
    --button-font-xs: 0.875rem;
    --button-font-sm: 0.9375rem;
    --button-font-md: 1rem;
    --button-font-lg: 1.125rem;
    --button-font-xl: 1.25rem;
    
    /* Button Border Radius */
    --button-radius-sharp: 4px;
    --button-radius-default: 8px;
    --button-radius-rounded: 25px;
    --button-radius-pill: 50px;
    
    /* Transition */
    --button-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Base Button Reset */
.btn,
button,
[type="button"],
[type="submit"],
[type="reset"] {
    font-family: inherit;
    font-weight: 600;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: var(--button-transition);
    position: relative;
    overflow: hidden;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

/* Button Base Class */
.btn {
    padding: var(--button-padding-md);
    min-height: var(--button-height-md);
    font-size: var(--button-font-md);
    border-radius: var(--button-radius-default);
    gap: 0.5rem;
}

/* Button Sizes */
.btn--xs {
    padding: var(--button-padding-xs);
    min-height: var(--button-height-xs);
    font-size: var(--button-font-xs);
}

.btn--sm {
    padding: var(--button-padding-sm);
    min-height: var(--button-height-sm);
    font-size: var(--button-font-sm);
}

.btn--md {
    padding: var(--button-padding-md);
    min-height: var(--button-height-md);
    font-size: var(--button-font-md);
}

.btn--lg {
    padding: var(--button-padding-lg);
    min-height: var(--button-height-lg);
    font-size: var(--button-font-lg);
}

.btn--xl {
    padding: var(--button-padding-xl);
    min-height: var(--button-height-xl);
    font-size: var(--button-font-xl);
}

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

.btn--primary:hover {
    background: var(--accent-turquoise);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(3, 196, 235, 0.3);
}

.btn--primary:active {
    transform: translateY(0);
    box-shadow: 0 2px 8px rgba(3, 196, 235, 0.3);
}

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

.btn--secondary:hover {
    background: var(--gray-800);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 26, 46, 0.3);
}

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

.btn--success:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(40, 167, 69, 0.3);
}

.btn--warning {
    background: var(--warning-color, var(--color-warning));
    color: var(--gray-900);
}

.btn--warning:hover {
    background: #e0a800;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 193, 7, 0.3);
}

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

.btn--error:hover {
    background: #c82333;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(220, 53, 69, 0.3);
}

/* Outline Buttons */
.btn--outline {
    background: transparent;
    border: 2px solid currentColor;
}

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

.btn--outline-primary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(3, 196, 235, 0.2);
}

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

.btn--outline-secondary:hover {
    background: var(--secondary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 26, 46, 0.2);
}

/* Ghost Buttons */
.btn--ghost {
    background: transparent;
    color: var(--gray-700);
    border: none;
}

.btn--ghost:hover {
    background: var(--gray-100);
    color: var(--gray-900);
}

/* Button Shapes */
.btn--rounded {
    border-radius: var(--button-radius-rounded);
}

.btn--pill {
    border-radius: var(--button-radius-pill);
}

.btn--square {
    border-radius: var(--button-radius-sharp);
}

.btn--circle {
    border-radius: 50%;
    width: var(--button-height-md);
    height: var(--button-height-md);
    padding: 0;
}

/* Button States */
.btn:disabled,
.btn--disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

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

.btn--loading::after {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    top: 50%;
    left: 50%;
    margin-left: -10px;
    margin-top: -10px;
    border: 2px solid currentColor;
    border-radius: 50%;
    border-top-color: transparent;
    animation: btn-spinner 0.8s linear infinite;
}

/* Full Width Button */
.btn--block {
    width: 100%;
    display: flex;
}

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

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

.btn-group .btn:not(:last-child) {
    border-right: 1px solid rgba(255, 255, 255, 0.2);
}

/* Icon Buttons */
.btn--icon-left svg,
.btn--icon-left i {
    margin-right: 0.5rem;
}

.btn--icon-right svg,
.btn--icon-right i {
    margin-left: 0.5rem;
}

.btn--icon-only {
    padding: 0;
    width: var(--button-height-md);
    height: var(--button-height-md);
}

/* Ripple Effect */
.btn--ripple {
    position: relative;
    overflow: hidden;
}

.btn--ripple::before {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn--ripple:active::before {
    width: 300px;
    height: 300px;
}

/* Focus States */
.btn:focus-visible {
    outline: 3px solid var(--primary-color);
    outline-offset: 2px;
}

/* Animations */
@keyframes btn-spinner {
    to {
        transform: rotate(360deg);
    }
}

/* Responsive Adjustments */
@media screen and (max-width: 768px) {
    /* Adjust button sizes on mobile */
    .btn--md {
        padding: var(--button-padding-sm);
        min-height: var(--button-height-sm);
        font-size: var(--button-font-sm);
    }
    
    .btn--lg {
        padding: var(--button-padding-md);
        min-height: var(--button-height-md);
        font-size: var(--button-font-md);
    }
    
    /* Ensure minimum touch target size (44px) */
    .btn {
        min-height: 44px;
        min-width: 44px;
    }
}

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
    .btn--outline {
        border-color: var(--gray-600);
    }
    
    .btn--ghost:hover {
        background: var(--gray-800);
        color: var(--gray-100);
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    .btn {
        border: 2px solid currentColor;
    }
    
    .btn:hover {
        text-decoration: underline;
    }
}

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