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a{color:var(--primary-light);text-decoration:none;font-size:.9375rem;transition:all .3s ease;font-weight:500}.footer a:hover{color:#fff;text-decoration:underline}.footer-section .footer-links a{color:hsla(0,0%,100%,.75);font-size:.9375rem;position:relative;padding-left:0;transition:all .3s cubic-bezier(.4,0,.2,1);display:inline-block}.footer-section .footer-links a:before{content:"→";position:absolute;left:-1rem;opacity:0;transform:translateX(-5px);transition:all .3s ease;color:var(--primary-color)}.footer-section .footer-links a:hover{color:#fff;padding-left:1rem;text-decoration:none}.footer-section .footer-links a:hover:before{opacity:1;transform:translateX(0)}.footer-bottom{text-align:center;padding-top:1.5rem;border-top:1px solid hsla(0,0%,100%,.1);position:relative}.footer-bottom:before{content:"";position:absolute;top:0;left:50%;transform:translateX(-50%);width:100px;height:1px;background:var(--primary-gradient)}.footer-bottom p{margin:0;color:hsla(0,0%,100%,.7);font-size:.9375rem;font-weight:400}.footer-bottom a{color:var(--primary-light);font-weight:600;transition:all .3s ease}.footer-bottom a:hover{color:#fff;text-decoration:none}@media (max-width:768px){.nav:not(.nav-open){display:none}.hero{padding:4rem 0}.hero h1{font-size:2.25rem}.hero-subtitle{font-size:1.125rem}h2{font-size:2rem}.features-grid,.topics-grid,.use-cases-grid{grid-template-columns:1fr}.step{flex-direction:column;text-align:center}.step-number{margin:0 auto}section{padding:3.5rem 0}.footer{padding:2.5rem 0 1.5rem}.footer-main{grid-template-columns:repeat(3,1fr);gap:2rem}}@media (max-width:640px){.footer-main{grid-template-columns:1fr;gap:2rem}.footer-section{text-align:left}.footer-section h3{font-size:1.125rem}.footer-section .footer-links{align-items:flex-start}.footer-section .footer-links a:hover{padding-left:.75rem}}@media (max-width:480px){.container{padding:0 20px}.hero{padding:3rem 0}.hero 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1;background:var(--surface-color);color:var(--text-secondary);border:1px solid var(--border-color);font-size:.875rem;padding:.75rem;min-height:auto}.keypad-btn-word:hover{background:rgba(99,102,241,.1);color:var(--primary-color);border-color:var(--primary-light)}@media (max-width:968px){.calculator-layout{grid-template-columns:1fr;gap:1.5rem}.keypad-container{position:static}}@media (max-width:768px){.calculator-section{padding:3.5rem 0}.calculator-container{padding:1.5rem;border-radius:16px}.input-group{flex-direction:column}.calculate-btn{width:100%;padding:1rem}.operation-buttons{justify-content:center}.result-value{font-size:1.5rem}.result-main,.result-steps{padding:1.25rem 1.5rem}.keypad-btn{padding:.875rem .25rem;font-size:1rem;min-height:48px}.keypad-container{padding:1rem}}@media (max-width:480px){.calculator-container{padding:1.25rem}.calculator-input{font-size:1rem;padding:.875rem 1rem}.operation-btn{padding:.5rem 1rem;font-size:.875rem}.example-btn{font-size:.75rem;padding:.375rem .75rem}.step-item{font-size:.875rem;padding-left:2rem}.step-item:before{width:1.25rem;height:1.25rem;font-size:.625rem}.keypad-btn{padding:.75rem .125rem;font-size:.9rem;min-height:44px;border-radius:8px}.keypad,.keypad-row{gap:.375rem}.keypad-extra{flex-wrap:wrap}.keypad-btn-word{font-size:.75rem;padding:.625rem}}