.bottom-nav{position:fixed;z-index:20;bottom:0;left:50%;transform:translateX(-50%);width:min(760px,100%);display:grid;grid-template-columns:repeat(4,1fr);background:rgba(255,255,255,.94);border-top:1px solid var(--line);backdrop-filter:blur(18px);padding:10px 10px max(10px,env(safe-area-inset-bottom));box-shadow:0 -12px 35px rgba(33,49,92,.08)}.nav-item{display:flex;flex-direction:column;align-items:center;gap:2px;color:#8c94a7;font-weight:700}.nav-item span{font-size:1.35rem}.nav-item small{font-size:.67rem;color:inherit}.nav-item.is-active{color:var(--primary)}.brand-row,.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:22px}.brand{font-weight:900;font-size:2rem;color:#1f55d5;letter-spacing:-.05em}.brand span{color:#6f47ec}.icon-button{width:44px;height:44px;border-radius:14px;border:0;background:#fff;box-shadow:0 8px 24px rgba(40,59,113,.1);font-size:1.2rem}.topbar>div{text-align:center}.topbar h1{font-size:1.25rem}.section-heading{display:flex;align-items:end;justify-content:space-between;margin:28px 0 14px}.section-heading>a,.section-heading>span{font-size:.82rem;color:var(--primary);font-weight:800}.stats-grid{display:grid;gap:10px}.stats-grid--three{grid-template-columns:repeat(3,1fr)}.stat{background:#fff;border:1px solid var(--line);border-radius:18px;padding:16px 8px;text-align:center;box-shadow:0 8px 22px rgba(48,64,110,.06)}.stat span{display:block;font-size:1.25rem}.stat strong{display:block;font-size:1.35rem;margin:4px 0}.stat small{font-size:.68rem}.mastery-bar,.mini-progress{height:7px;background:#edf0f7;border-radius:99px;overflow:hidden}.mastery-bar span,.mini-progress span{height:100%;display:block;background:linear-gradient(90deg,#36c86b,#68d5a0);border-radius:inherit}.progress-ring{--value:0;width:96px;height:96px;border-radius:50%;background:conic-gradient(#43c778 calc(var(--value)*1%),#ebeff6 0);display:grid;place-items:center;flex:none}.progress-ring:before{content:"";position:absolute;width:74px;height:74px;border-radius:50%;background:#fff}.progress-ring>div{position:relative;text-align:center;z-index:1}.progress-ring strong{display:block;font-size:1.2rem}.progress-ring span{font-size:.62rem;color:var(--muted)}.toast{position:fixed;z-index:100;top:18px;left:50%;transform:translate(-50%,-16px);opacity:0;background:#1d2a47;color:#fff;border-radius:14px;padding:12px 18px;box-shadow:var(--shadow);transition:.2s;max-width:90%;text-align:center}.toast.is-visible{transform:translate(-50%,0);opacity:1}.toast--success{background:#198947}.toast--warning{background:#a76307}