.introduction-section p{margin-bottom:1.2em;font-size:1.05em}.introduction-section strong{font-weight:600;color:var(--body-text)}.introduction-section .steps-list{counter-reset:step-counter;list-style:none;padding-left:0;margin:1.5rem 0}.introduction-section .steps-list>li{counter-increment:step-counter;position:relative;padding-left:3.5rem;margin-bottom:2rem}.introduction-section .steps-list>li:last-child{margin-bottom:1rem}.introduction-section .steps-list>li:before{content:counter(step-counter);position:absolute;left:0;top:0;display:flex;align-items:center;justify-content:center;width:2.5rem;height:2.5rem;background:linear-gradient(135deg,#1d8aff,#0097e9);color:var(--header-text);border-radius:50%;font-weight:700;font-size:1.125rem;box-shadow:0 4px 8px #0000001a;transition:scale .25s cubic-bezier(.68,-.55,.265,1.55)}.introduction-section .steps-list>li:not(:last-child):after{content:"";position:absolute;left:1.25rem;top:2.5rem;width:2px;height:calc(100% - 1.5rem);background:linear-gradient(180deg,#1d8aff66,#0097e91a)}.introduction-section .steps-list>li:hover:before{scale:1.1}.introduction-section .steps-list>li ul{margin-top:.75rem;margin-left:1.5rem}.introduction-section .steps-list>li ul li{margin-bottom:.5rem}.introduction-section .steps-list>li ul li::marker{color:#1d8aff}.categories-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(500px,100%),1fr));gap:1.5rem}.categories-grid .category-card{background-color:var(--card-bg);border-radius:1rem;padding:1.5rem;display:flex;flex-direction:column;gap:1rem;box-shadow:0 4px 8px #0000001a;border:1px solid var(--card-border);position:relative;isolation:isolate;overflow:hidden}.categories-grid .category-card:before{content:"";position:absolute;inset:0;background:linear-gradient(135deg,#1d8aff08,#0097e903);border-radius:inherit;opacity:1;z-index:-1}.categories-grid .category-card{opacity:0;animation:fadeIn .5s cubic-bezier(0,0,.2,1) forwards}.categories-grid .category-card:nth-child(10n-9){animation-delay:.1s}.categories-grid .category-card:nth-child(10n-8){animation-delay:.2s}.categories-grid .category-card:nth-child(10n-7){animation-delay:.3s}.categories-grid .category-card:nth-child(10n-6){animation-delay:.4s}.categories-grid .category-card:nth-child(10n-5){animation-delay:.5s}.categories-grid .category-card:nth-child(10n-4){animation-delay:.6s}.categories-grid .category-card:nth-child(10n-3){animation-delay:.7s}.categories-grid .category-card:nth-child(10n-2){animation-delay:.8s}.categories-grid .category-card:nth-child(10n-1){animation-delay:.9s}.categories-grid .category-card:nth-child(10n-0){animation-delay:1s}.categories-grid .category-card{transition:translate .25s cubic-bezier(0,0,.2,1),box-shadow .25s cubic-bezier(0,0,.2,1)}.categories-grid .category-card:hover{translate:0 -2px;box-shadow:0 8px 16px #0000001f}.categories-grid .category-card .category-title{line-height:1.25;font-weight:600;color:var(--section-title);width:fit-content;position:relative;display:inline-block}.categories-grid .category-card .category-title:after{content:"";position:absolute;bottom:calc(-.25rem - 1.5px);left:0;width:100%;height:3px;background:linear-gradient(90deg,#1d8aff,#0097e9);border-radius:9999px}.categories-grid .category-card .category-description{color:var(--body-text);line-height:1.625;opacity:.9}.categories-grid .category-card .modes-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(200px,100%),1fr));gap:1rem}.categories-grid .category-card .modes-grid .mode-card{background-color:var(--card-bg);padding:1rem;border-radius:.75rem;box-shadow:0 2px 4px #00000014;border:1px solid var(--card-border);text-decoration:none;color:inherit;transition:scale .25s cubic-bezier(0,0,.2,1),box-shadow .25s cubic-bezier(0,0,.2,1),translate .25s cubic-bezier(0,0,.2,1)}.categories-grid .category-card .modes-grid .mode-card:hover{scale:1.05;translate:0 -4px;box-shadow:0 8px 16px #0000001f}.categories-grid .category-card .modes-grid .mode-card:hover .material-symbols-outlined{scale:1.15}.categories-grid .category-card .modes-grid .mode-card:active{scale:1.02;translate:0 -2px}.categories-grid .category-card .modes-grid .mode-card .material-symbols-outlined{transition:scale .35s cubic-bezier(.68,-.55,.265,1.55)}@keyframes gradient-shift{0%,to{background-position:0% 50%}50%{background-position:100% 50%}}.step-by-step{--bor: var(--card-border);--bdr: 2rem;--pad: 1rem;box-sizing:border-box;background-color:var(--card-bg);padding:1rem;border:solid 1px var(--card-border);border-radius:2rem;display:flex;flex-direction:column;gap:var(--pad)}.step-by-step .divider{border:none;height:1px;background-color:var(--bor)}.step-by-step .step{box-sizing:border-box;background-color:var(--card-bg)}.step-by-step .step .correct-explanation{box-sizing:border-box;margin-top:var(--pad);padding:var(--pad);background-color:rgba(from var(--card-bg) h s calc(l - 3%));border-radius:calc(var(--bdr) / 8);position:relative;overflow:hidden}.step-by-step .step .correct-explanation:before{content:"";position:absolute;inset:0;width:calc(var(--bdr) / 8);height:100%;background-color:#2d2}.step-by-step .step .step-question-choices{display:flex;flex-direction:column;gap:1rem;padding:1rem;border:solid 1px var(--card-border);border-radius:1rem}.step-by-step .step .step-question-choices .step-question-choice{position:relative;background-color:var(--card-bg);cursor:pointer;border-radius:100dvw;padding-inline:1ex;transition:background-color .2s ease,transform .1s ease}.step-by-step .step .step-question-choices .step-question-choice:hover:not([data-state]){background-color:rgba(from lightblue r g b/.3)}.step-by-step .step .step-question-choices .step-question-choice:active{transform:scale(.98)}.step-by-step .step .step-question-choices .step-question-choice[data-state=selected-correct]{background-color:#91ee91}.step-by-step .step .step-question-choices .step-question-choice[data-state=hint-correct]{background-color:#91ee9180}.step-by-step .step .step-question-choices .step-question-choice[data-state=selected-incorrect]{background-color:#f99}.step-by-step .step .step-question-choices .step-question-choice[data-state=hint-incorrect]{background-color:#ff999980}.step-by-step .step .step-question-choices .step-question-choice .step-question-radio{visibility:hidden;position:absolute;width:0;height:0;top:-1px;left:-1px}