:root{--transition-fast:150ms cubic-bezier(0.4,0,0.2,1);--transition-normal:250ms cubic-bezier(0.4,0,0.2,1);--transition-slow:350ms cubic-bezier(0.4,0,0.2,1);--button-height-sm:32px;--button-height-md:40px;--button-height-lg:48px;--input-height-sm:32px;--input-height-md:40px;--input-height-lg:48px;--card-padding-sm:16px;--card-padding-md:24px;--card-padding-lg:32px}*{box-sizing:border-box}html{scroll-behavior:smooth}body{background:var(--bg-primary);color:var(--text-primary);transition:background-color var(--transition-normal),color var(--transition-normal)}:focus{outline:2px solid var(--color-primary-500);outline-offset:2px}:focus:not(:focus-visible){outline:none}::selection{background-color:rgb(168 85 247/.2);color:var(--text-primary)}.gradient-text{background:linear-gradient(135deg,var(--color-primary-500) 0,var(--color-secondary-500) 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}.gradient-bg-primary{background:var(--bg-gradient)}.gradient-bg-brand{background:linear-gradient(135deg,var(--color-primary-500) 0,var(--color-secondary-500) 100%)}.card-elevated{background:var(--bg-primary);border:1px solid var(--border-primary);box-shadow:var(--shadow-md);transition:all var(--transition-normal)}.card-elevated:hover{box-shadow:var(--shadow-lg);transform:translateY(-2px)}.interactive{cursor:pointer;transition:all var(--transition-fast)}.interactive:hover{transform:translateY(-1px)}.interactive:active{transform:translateY(0)}.glass{background:rgba(255,255,255,.1);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.2)}.math-accent{color:#8b5cf6}.ai-accent{color:#ec4899}.progress-accent{color:#10b981}.streak-accent{color:#f59e0b}.animate-fade-in{animation:fadeIn var(--transition-normal) ease-out}.animate-slide-up{animation:slideUp var(--transition-normal) ease-out}.animate-scale-in{animation:scaleIn var(--transition-normal) ease-out}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes scaleIn{0%{opacity:0;transform:scale(.95)}to{opacity:1;transform:scale(1)}}@media (max-width:640px){.hide-mobile{display:none}}@media (min-width:641px){.show-mobile{display:none}}@media (max-width:768px){.hide-tablet{display:none}}@media (min-width:769px){.show-tablet{display:none}}@media (prefers-reduced-motion:reduce){*{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}@media print{.no-print{display:none!important}}.dark .card-elevated{background:var(--bg-secondary);border-color:var(--border-primary)}.dark .glass{background:rgba(0,0,0,.3);border-color:rgba(255,255,255,.1)}.expert-feedback_fab__OCA19{position:fixed;z-index:40;right:max(16px,env(safe-area-inset-right));bottom:calc(16px + env(safe-area-inset-bottom));display:inline-flex;align-items:center;justify-content:center;gap:8px;min-width:48px;height:48px;padding:0;border:1px solid rgb(255 255 255/28%);border-radius:var(--agai-radius-pill,999px);background:linear-gradient(135deg,var(--agai-color-primary,#135ef2),var(--agai-color-gradient-end,#445cf7));box-shadow:0 10px 24px rgb(19 94 242/32%),0 2px 6px rgb(16 24 40/12%);color:#fff;font-family:var(--agai-font-primary,inherit);font-size:14px;font-weight:700;line-height:1;cursor:pointer;-webkit-tap-highlight-color:transparent;transition:transform var(--agai-motion-quick,.18s) var(--agai-ease-standard,ease),box-shadow var(--agai-motion-quick,.18s) var(--agai-ease-standard,ease);animation:expert-feedback_fab-in__4Jow2 .32s var(--agai-ease-standard,ease) both}.expert-feedback_fab__OCA19:hover{box-shadow:0 14px 30px rgb(19 94 242/38%),0 2px 8px rgb(16 24 40/14%);transform:translateY(-1px)}.expert-feedback_fab__OCA19:active{transform:scale(var(--agai-pressed-scale,.975))}.expert-feedback_fab__OCA19:focus-visible{outline:3px solid rgb(19 94 242/40%);outline-offset:3px}.expert-feedback_fabIcon__u1Yc3{flex-shrink:0}.expert-feedback_fabLabel__6tIfw{display:none;white-space:nowrap}@media (max-width:1023px){body.agai-has-mobile-bottom-nav .expert-feedback_fab__OCA19{bottom:calc(92px + env(safe-area-inset-bottom))}}@media (min-width:640px){.expert-feedback_fab__OCA19{right:24px;bottom:24px;height:52px;padding:0 20px 0 16px}.expert-feedback_fabLabel__6tIfw{display:inline}}.expert-feedback_overlay__cus7n{position:fixed;inset:0;z-index:70;background:rgb(15 23 42/48%);backdrop-filter:blur(2px);animation:expert-feedback_overlay-in__3yHz9 .18s ease-out both}.expert-feedback_overlay__cus7n[data-state=closed]{animation:expert-feedback_overlay-out__MYJ2U .15s ease-in both}.expert-feedback_content__t8xCT{position:fixed;z-index:71;right:0;bottom:0;left:0;display:flex;max-height:92dvh;flex-direction:column;overflow:hidden;border:1px solid rgb(255 255 255/80%);border-bottom:0;border-radius:24px 24px 0 0;background:var(--agai-glass-card-fill,rgb(255 255 255/96%));box-shadow:0 -18px 60px rgb(15 23 42/22%);color:var(--agai-color-ink,#111827);font-family:var(--agai-font-primary,inherit);backdrop-filter:blur(24px) saturate(145%);animation:expert-feedback_sheet-in__y5RPq .26s var(--agai-ease-standard,ease-out) both}.expert-feedback_content__t8xCT[data-state=closed]{animation:expert-feedback_sheet-out__3Pfo0 .2s ease-in both}.expert-feedback_scroll__GZP41{min-height:0;flex:1 1 auto;overflow-x:hidden;overflow-y:auto;overscroll-behavior:contain;padding:8px 16px calc(20px + env(safe-area-inset-bottom))}.expert-feedback_grabber__fIZfk{width:40px;height:4px;flex-shrink:0;margin:8px auto 0;border-radius:999px;background:var(--agai-color-border,#e4e8ef)}@media (min-width:640px){.expert-feedback_content__t8xCT{top:50%;right:auto;bottom:auto;left:50%;width:min(520px,calc(100vw - 32px));max-height:min(90dvh,780px);border-bottom:1px solid rgb(255 255 255/80%);border-radius:24px;box-shadow:0 32px 90px rgb(15 23 42/22%),0 8px 28px rgb(37 99 235/12%);transform:translate(-50%,-50%);animation:expert-feedback_dialog-in__JsWcx .2s var(--agai-ease-standard,ease-out) both}.expert-feedback_content__t8xCT[data-state=closed]{animation:expert-feedback_dialog-out__Rp1rb .15s ease-in both}.expert-feedback_scroll__GZP41{padding:28px}.expert-feedback_grabber__fIZfk{display:none}}@keyframes expert-feedback_fab-in__4Jow2{0%{opacity:0;transform:scale(.8)}to{opacity:1;transform:scale(1)}}@keyframes expert-feedback_overlay-in__3yHz9{0%{opacity:0}to{opacity:1}}@keyframes expert-feedback_overlay-out__MYJ2U{0%{opacity:1}to{opacity:0}}@keyframes expert-feedback_sheet-in__y5RPq{0%{transform:translateY(100%)}to{transform:translateY(0)}}@keyframes expert-feedback_sheet-out__3Pfo0{0%{transform:translateY(0)}to{transform:translateY(100%)}}@keyframes expert-feedback_dialog-in__JsWcx{0%{opacity:0;transform:translate(-50%,-48%) scale(.96)}to{opacity:1;transform:translate(-50%,-50%) scale(1)}}@keyframes expert-feedback_dialog-out__Rp1rb{0%{opacity:1;transform:translate(-50%,-50%) scale(1)}to{opacity:0;transform:translate(-50%,-48%) scale(.96)}}@media (prefers-reduced-motion:reduce){.expert-feedback_content__t8xCT,.expert-feedback_fab__OCA19,.expert-feedback_overlay__cus7n{animation:none!important;transition:none}}.mobile-app-promo-modal_modal__UmgNk{width:min(620px,calc(100vw - 24px))!important;max-width:620px!important;max-height:calc(100dvh - 24px);overflow:auto;gap:0!important;padding:0!important;border:1px solid rgba(255,255,255,.82)!important;border-radius:30px!important;background:rgba(255,255,255,.96)!important;color:#0f172a;box-shadow:0 32px 90px rgba(15,23,42,.22),0 8px 28px rgba(37,99,235,.12)!important;backdrop-filter:blur(24px) saturate(145%)}.mobile-app-promo-modal_closeButton__q5bJT{position:absolute;z-index:3;top:18px;right:18px;display:grid;width:36px;height:36px;place-items:center;border:1px solid rgba(148,163,184,.2);border-radius:999px;background:rgba(255,255,255,.72);color:#475569;box-shadow:0 4px 18px rgba(15,23,42,.08);transition:transform .18s ease,background .18s ease,color .18s ease;backdrop-filter:blur(14px)}.mobile-app-promo-modal_closeButton__q5bJT:hover{transform:scale(1.05);background:#fff;color:#0f172a}.mobile-app-promo-modal_browserButton__l9Wof:focus-visible,.mobile-app-promo-modal_closeButton__q5bJT:focus-visible,.mobile-app-promo-modal_storeCard__AvO_2:focus-visible{outline:3px solid rgba(37,99,235,.28);outline-offset:3px}.mobile-app-promo-modal_hero__vRx21{position:relative;display:flex;min-height:190px;align-items:center;justify-content:center;overflow:hidden;padding:34px;background:radial-gradient(circle at 22% 20%,rgba(125,211,252,.34),transparent 35%),radial-gradient(circle at 82% 74%,rgba(129,140,248,.3),transparent 38%),linear-gradient(145deg,#f8fbff,#eef4ff 46%,#f7f4ff);border-bottom:1px solid rgba(148,163,184,.16)}.mobile-app-promo-modal_mathMark__W5Qei,.mobile-app-promo-modal_orb__6tNDp{position:absolute;pointer-events:none}.mobile-app-promo-modal_orb__6tNDp{width:170px;height:170px;border:1px solid rgba(59,130,246,.16);border-radius:999px}.mobile-app-promo-modal_orbOne___n5ph{top:-92px;left:-55px}.mobile-app-promo-modal_orbTwo__LjBSl{right:-65px;bottom:-112px;width:220px;height:220px}.mobile-app-promo-modal_mathMark__W5Qei{color:rgba(37,99,235,.18);font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:20px;font-weight:700}.mobile-app-promo-modal_markOne___zmRn{top:34px;left:72px;transform:rotate(-8deg)}.mobile-app-promo-modal_markTwo__hEA7_{right:70px;bottom:30px;transform:rotate(7deg)}.mobile-app-promo-modal_appIconWrap__C1Tbu{position:relative}.mobile-app-promo-modal_appIconGlow__ytF_B{position:absolute;inset:10px;border-radius:30px;background:rgba(37,99,235,.5);filter:blur(30px)}.mobile-app-promo-modal_appIcon__1ilZR{position:relative;display:grid;width:104px;height:104px;place-items:center;overflow:hidden;border:1px solid rgba(255,255,255,.7);border-radius:27px;background:linear-gradient(150deg,#17347f,#2764e8 54%,#3b8df5);box-shadow:inset 0 1px 0 rgba(255,255,255,.3),0 20px 42px rgba(37,99,235,.28);color:#fff;font-size:29px;font-weight:800;letter-spacing:-1.8px}.mobile-app-promo-modal_appIcon__1ilZR:after{position:absolute;right:20px;bottom:23px;width:25px;height:3px;border-radius:99px;background:linear-gradient(90deg,#fff,#a5dcff);content:""}.mobile-app-promo-modal_syncBadge__JUar8{position:absolute;right:-77px;bottom:3px;display:flex;align-items:center;gap:6px;white-space:nowrap;padding:7px 10px;border:1px solid rgba(255,255,255,.9);border-radius:999px;background:rgba(255,255,255,.84);color:#1e3a8a;box-shadow:0 8px 24px rgba(30,64,175,.12);font-size:11px;font-weight:700;backdrop-filter:blur(12px)}.mobile-app-promo-modal_syncBadge__JUar8 svg{width:13px;height:13px;stroke-width:3}.mobile-app-promo-modal_content__F7Yil{padding:29px 32px 26px}.mobile-app-promo-modal_eyebrow___9BK0{margin:0 0 9px;color:#2563eb;font-size:12px;font-weight:800;letter-spacing:.13em;text-align:center;text-transform:uppercase}.mobile-app-promo-modal_title__E_0L4{margin:0;color:#0f172a;font-size:clamp(27px,4.4vw,36px)!important;font-weight:760!important;letter-spacing:-.035em;line-height:1.08!important;text-align:center}.mobile-app-promo-modal_description__s0UTY{max-width:510px;margin:13px auto 0;color:#64748b!important;font-size:15px!important;line-height:1.55!important;text-align:center}.mobile-app-promo-modal_benefit__C5DKm{display:flex;width:fit-content;align-items:center;gap:7px;margin:18px auto 0;padding:8px 12px;border:1px solid rgba(37,99,235,.12);border-radius:999px;background:#f6f9ff;color:#36527f;font-size:12px;font-weight:650}.mobile-app-promo-modal_benefit__C5DKm svg{width:14px;height:14px;color:#2563eb;stroke-width:3}.mobile-app-promo-modal_storeGrid__ekBpt{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:22px}.mobile-app-promo-modal_storeCard__AvO_2{display:flex;min-height:88px;align-items:center;gap:12px;padding:15px;border-radius:20px;text-decoration:none;transition:transform .19s cubic-bezier(.22,1,.36,1),box-shadow .19s ease,border-color .19s ease}.mobile-app-promo-modal_storeCard__AvO_2:hover{transform:translateY(-2px)}.mobile-app-promo-modal_appleCard__NAhLm{border:1px solid #111827;background:#111318;color:#fff;box-shadow:0 12px 28px rgba(15,23,42,.13)}.mobile-app-promo-modal_appleCard__NAhLm:hover{box-shadow:0 16px 34px rgba(15,23,42,.2)}.mobile-app-promo-modal_playCard__CvDaY{border:1px solid #dfe7f3;background:#fff;color:#0f172a;box-shadow:0 10px 26px rgba(37,99,235,.07)}.mobile-app-promo-modal_playCard__CvDaY:hover{border-color:#bfdbfe;box-shadow:0 15px 32px rgba(37,99,235,.12)}.mobile-app-promo-modal_storeIcon__9p2EX{display:grid;width:43px;height:43px;flex:0 0 43px;place-items:center;border-radius:13px}.mobile-app-promo-modal_storeIcon__9p2EX svg{width:23px;height:23px}.mobile-app-promo-modal_appleCard__NAhLm .mobile-app-promo-modal_storeIcon__9p2EX{background:rgba(255,255,255,.1)}.mobile-app-promo-modal_playCard__CvDaY .mobile-app-promo-modal_storeIcon__9p2EX{background:linear-gradient(145deg,#e7f0ff,#eefcfb);color:#2563eb}.mobile-app-promo-modal_storeText__ZwUJe{min-width:0;flex:1}.mobile-app-promo-modal_storeStatus__sRtsu{display:block;margin-bottom:3px;opacity:.68;font-size:10px;font-weight:750;letter-spacing:.08em;text-transform:uppercase}.mobile-app-promo-modal_storeAction__1U4uG{display:block;font-size:14px;font-weight:750;letter-spacing:-.01em;line-height:1.25}.mobile-app-promo-modal_storeArrow__3s9lZ{width:16px;height:16px;flex:0 0 16px;opacity:.55}.mobile-app-promo-modal_androidNote__BVw0h{margin:12px 2px 0;color:#64748b;font-size:12px;line-height:1.45;text-align:center}.mobile-app-promo-modal_browserButton__l9Wof{display:block;margin:17px auto 0;padding:7px 10px;border-radius:10px;color:#64748b;font-size:13px;font-weight:650;text-decoration:underline;text-decoration-color:rgba(100,116,139,.34);text-underline-offset:4px;transition:color .16s ease}.mobile-app-promo-modal_browserButton__l9Wof:hover{color:#1e293b}@media (max-width:639px){.mobile-app-promo-modal_modal__UmgNk{--tw-translate-x:0px!important;--tw-translate-y:0px!important;right:12px!important;left:12px!important;width:auto!important;top:auto!important;bottom:max(12px,env(safe-area-inset-bottom))!important;transform:none!important;translate:none!important;border-radius:28px!important}.mobile-app-promo-modal_hero__vRx21{min-height:154px;padding:28px}.mobile-app-promo-modal_appIcon__1ilZR{width:88px;height:88px;border-radius:23px;font-size:25px}.mobile-app-promo-modal_appIcon__1ilZR:after{right:16px;bottom:20px;width:23px}.mobile-app-promo-modal_syncBadge__JUar8{right:-70px;bottom:-2px}.mobile-app-promo-modal_markOne___zmRn{left:32px}.mobile-app-promo-modal_markTwo__hEA7_{right:32px}.mobile-app-promo-modal_content__F7Yil{padding:24px 18px 20px}.mobile-app-promo-modal_storeGrid__ekBpt{grid-template-columns:1fr}.mobile-app-promo-modal_storeCard__AvO_2{min-height:76px;padding:13px 14px}.mobile-app-promo-modal_androidNote__BVw0h{padding-inline:8px}}@media (prefers-reduced-motion:reduce){.mobile-app-promo-modal_closeButton__q5bJT,.mobile-app-promo-modal_storeCard__AvO_2{transition:none}}