.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.625rem 1.25rem;font-family:var(--font-family-sans);font-size:var(--font-size-sm);font-weight:var(--font-weight-semibold);line-height:1.5;text-align:center;text-decoration:none;white-space:nowrap;border:1px solid transparent;border-radius:var(--radius-lg);background-color:transparent;cursor:pointer;-webkit-user-select:none;user-select:none;transition:all var(--transition-fast);appearance:none;-webkit-appearance:none;-moz-appearance:none}.btn::selection{background:transparent}.btn:focus{outline:none}.btn-primary{background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-primary-dark) 100%);color:#fff;border-color:transparent;box-shadow:0 4px 12px #6366f14d}.btn-primary:hover{background:linear-gradient(135deg,var(--color-primary-vivid) 0%,var(--color-primary) 100%);transform:translateY(-2px);box-shadow:0 6px 16px #6366f166}.btn-primary:active{transform:translateY(0);box-shadow:0 2px 8px #6366f14d}.btn-secondary{background-color:#fff;color:var(--color-text-primary);border:1px solid var(--color-border-primary);box-shadow:var(--shadow-sm)}.btn-secondary:hover{background-color:var(--color-gray-50);border-color:var(--color-border-secondary);box-shadow:var(--shadow-md)}.btn-secondary:active{background-color:var(--color-gray-100);box-shadow:var(--shadow-sm)}.btn-outline{background-color:transparent;color:var(--color-primary);border:2px solid var(--color-primary)}.btn-outline:hover{background-color:var(--color-soft-purple);border-color:var(--color-primary-dark);color:var(--color-primary-dark)}.btn-outline:active{background-color:var(--color-primary-100)}.btn-ghost{background-color:transparent;color:var(--color-text-primary);border-color:transparent}.btn-ghost:hover{background-color:var(--color-gray-100);color:var(--color-primary)}.btn-ghost:active{background-color:var(--color-gray-200)}.btn-danger{background:linear-gradient(135deg,var(--color-danger) 0%,var(--color-danger-600) 100%);color:#fff;border-color:transparent;box-shadow:0 4px 12px #ef44444d}.btn-danger:hover{background:linear-gradient(135deg,var(--color-danger-600) 0%,var(--color-danger-700) 100%);transform:translateY(-2px);box-shadow:0 6px 16px #ef444466}.btn-danger:active{transform:translateY(0);box-shadow:0 2px 8px #ef44444d}.btn-success{background:linear-gradient(135deg,var(--color-success) 0%,var(--color-success-600) 100%);color:#fff;border-color:transparent;box-shadow:0 4px 12px #10b9814d}.btn-success:hover{background:linear-gradient(135deg,var(--color-success-600) 0%,var(--color-success-700) 100%);transform:translateY(-2px);box-shadow:0 6px 16px #10b98166}.btn-success:active{transform:translateY(0);box-shadow:0 2px 8px #10b9814d}.btn-warning{background:linear-gradient(135deg,var(--color-warning) 0%,var(--color-warning-600) 100%);color:#fff;border-color:transparent;box-shadow:0 4px 12px #f59e0b4d}.btn-warning:hover{background:linear-gradient(135deg,var(--color-warning-600) 0%,var(--color-warning-700) 100%);transform:translateY(-2px);box-shadow:0 6px 16px #f59e0b66}.btn-warning:active{transform:translateY(0);box-shadow:0 2px 8px #f59e0b4d}.btn-xs{padding:.375rem .75rem;font-size:var(--font-size-xs);border-radius:var(--radius-md)}.btn-sm{padding:.5rem 1rem;font-size:var(--font-size-sm);border-radius:var(--radius-md)}.btn-md{padding:.625rem 1.25rem;font-size:var(--font-size-sm);border-radius:var(--radius-lg)}.btn-lg{padding:.75rem 1.5rem;font-size:var(--font-size-base);border-radius:var(--radius-xl)}.btn-xl{padding:1rem 2rem;font-size:var(--font-size-lg);border-radius:var(--radius-xl)}.btn:disabled,.btn.btn-disabled{opacity:.6;cursor:not-allowed;pointer-events:none}.btn.btn-loading{position:relative;color:transparent;pointer-events:none}.btn.btn-loading:after{content:"";position:absolute;top:50%;left:50%;width:16px;height:16px;margin-top:-8px;margin-left:-8px;border:2px solid currentColor;border-right-color:transparent;border-radius:50%;animation:spin .6s linear infinite}.btn-primary.btn-loading:after,.btn-danger.btn-loading:after,.btn-success.btn-loading:after,.btn-warning.btn-loading:after{border-color:#fff;border-right-color:transparent}.btn-secondary.btn-loading:after,.btn-outline.btn-loading:after,.btn-ghost.btn-loading:after{border-color:var(--color-primary);border-right-color:transparent}.btn:active:not(:disabled):not(.btn-disabled):not(.btn-loading){transform:scale(.98)}.btn-full-width,.btn-block{width:100%}.btn-icon{padding:.625rem;aspect-ratio:1}.btn-icon.btn-sm{padding:.5rem}.btn-icon.btn-lg{padding:.75rem}.btn-rounded{border-radius:var(--radius-full)}.btn-square{border-radius:0}.btn-group{display:inline-flex;gap:.5rem}.btn-group-vertical{display:inline-flex;flex-direction:column;gap:.5rem}.btn-group-connected{display:inline-flex;gap:0}.btn-group-connected .btn{border-radius:0;margin-left:-1px}.btn-group-connected .btn:first-child{border-top-left-radius:var(--radius-lg);border-bottom-left-radius:var(--radius-lg);margin-left:0}.btn-group-connected .btn:last-child{border-top-right-radius:var(--radius-lg);border-bottom-right-radius:var(--radius-lg)}.btn-group-connected .btn:hover{z-index:1}.btn-icon-left{flex-direction:row}.btn-icon-right{flex-direction:row-reverse}.btn svg,.btn .icon{width:1.25rem;height:1.25rem;flex-shrink:0}.btn-sm svg,.btn-sm .icon{width:1rem;height:1rem}.btn-lg svg,.btn-lg .icon{width:1.5rem;height:1.5rem}.btn-glass{background:#ffffffe6;backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border:1px solid rgba(255,255,255,.2);box-shadow:var(--shadow-md)}.btn-glass:hover{background:#fff;box-shadow:var(--shadow-lg)}.btn-gradient-border{position:relative;background:#fff;color:var(--color-primary);border:none;z-index:1}.btn-gradient-border:before{content:"";position:absolute;inset:-2px;border-radius:inherit;background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-accent-purple) 100%);z-index:-1}.btn-gradient-border:hover{transform:translateY(-2px)}.btn-fab{position:fixed;bottom:2rem;right:2rem;width:3.5rem;height:3.5rem;padding:0;border-radius:var(--radius-full);box-shadow:var(--shadow-xl);z-index:var(--z-index-fixed)}.btn-fab:hover{transform:translateY(-4px) scale(1.05);box-shadow:var(--shadow-2xl)}.btn-link{background:none;border:none;color:var(--color-primary);padding:0;font-weight:var(--font-weight-medium);text-decoration:underline;text-underline-offset:2px}.btn-link:hover{color:var(--color-primary-dark);text-decoration:underline;background:none;transform:none}.btn-link:active{transform:none}@media(max-width:640px){.btn{font-size:var(--font-size-sm)}.btn-lg{padding:.625rem 1.25rem;font-size:var(--font-size-base)}.btn-group-mobile-stack{flex-direction:column;width:100%}.btn-group-mobile-stack .btn{width:100%}.btn-fab{bottom:1rem;right:1rem}}body.theme-dark .btn-secondary{background-color:var(--color-gray-800);color:var(--color-gray-100);border-color:var(--color-gray-700)}body.theme-dark .btn-secondary:hover{background-color:var(--color-gray-700);border-color:var(--color-gray-600)}body.theme-dark .btn-ghost{color:var(--color-gray-100)}body.theme-dark .btn-ghost:hover{background-color:var(--color-gray-800)}body.theme-dark .btn-glass{background:#1f2937e6;border-color:#ffffff1a}body.theme-dark .btn-glass:hover{background:#1f2937}.btn:focus-visible{outline:2px solid var(--color-primary);outline-offset:2px}@media(prefers-contrast:high){.btn{border-width:2px}.btn-primary,.btn-danger,.btn-success,.btn-warning{border:2px solid currentColor}}@media(prefers-reduced-motion:reduce){.btn{transition:none}.btn:hover,.btn:active{transform:none}.btn.btn-loading:after{animation:none}}@media print{.btn{box-shadow:none;border:1px solid #000}.btn-fab{display:none}}