:root{--ink: #102426;--ink-soft: #3a5456;--paper: #f3f0e8;--teal: #0f3d3e;--teal-bright: #1a6b6d;--ok: #1f7a4c;--ok-bg: #d8f0e3;--bad: #b42318;--bad-bg: #fde8e6;--warn: #9a6700;--warn-bg: #fff3d6;--line: rgba(16, 36, 38, .12);--nav-h: 56px;--action-h: 64px;--safe-t: env(safe-area-inset-top, 0px);--safe-b: env(safe-area-inset-bottom, 0px);--safe-l: env(safe-area-inset-left, 0px);--safe-r: env(safe-area-inset-right, 0px);--font: "DM Sans", system-ui, sans-serif;--display: "Fraunces", Georgia, serif;--tap: clamp(48px, 12vw, 56px);--fs-xs: clamp(.68rem, .62rem + .35vw, .78rem);--fs-sm: clamp(.78rem, .72rem + .4vw, .9rem);--fs-md: clamp(.92rem, .86rem + .45vw, 1.05rem);--fs-lg: clamp(1.02rem, .94rem + .55vw, 1.2rem);--fs-xl: clamp(1.15rem, 1rem + 1vw, 1.4rem);--fs-display: clamp(1.22rem, 1.05rem + 1.4vw, 1.65rem);--fs-stat: clamp(1.35rem, 1.15rem + 1.5vw, 1.85rem);color:var(--ink);background:var(--paper);font-family:var(--font);font-size:clamp(15px,.55rem + 2.1vw,18px);line-height:1.45;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-webkit-tap-highlight-color:transparent;text-size-adjust:100%}*,*:before,*:after{box-sizing:border-box}html,body,#root{height:100%;max-width:100%;overflow:hidden}body{margin:0;min-height:100dvh;min-height:100svh;overscroll-behavior:none;background:radial-gradient(900px 420px at 0% -5%,rgba(26,107,109,.16),transparent 55%),radial-gradient(700px 360px at 100% 0%,rgba(196,92,38,.1),transparent 50%),var(--paper);touch-action:manipulation}button,input,textarea,select{font:inherit;font-size:max(16px,1rem)}button{cursor:pointer;touch-action:manipulation;-webkit-user-select:none;user-select:none}.app{height:100dvh;height:100svh;width:100%;max-width:480px;margin:0 auto;display:grid;grid-template-rows:auto minmax(0,1fr) auto;padding-left:max(12px,var(--safe-l));padding-right:max(12px,var(--safe-r));padding-top:var(--safe-t)}.topbar{padding:10px 2px 8px;display:flex;align-items:baseline;justify-content:space-between;gap:12px;flex-shrink:0}.brand{font-family:var(--display);font-size:var(--fs-xl);font-weight:700;color:var(--teal);letter-spacing:-.02em;line-height:1.1}.brand-sub{color:var(--ink-soft);font-size:var(--fs-xs);white-space:nowrap}.main{min-height:0;overflow:auto;overscroll-behavior:contain;-webkit-overflow-scrolling:touch;padding:4px 2px 12px;display:flex;flex-direction:column;gap:12px;scrollbar-width:thin}.nav{flex-shrink:0;display:grid;grid-template-columns:repeat(4,1fr);gap:2px;margin:0 -12px;padding:6px 8px calc(6px + var(--safe-b));background:#f3f0e8f5;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-top:1px solid var(--line);z-index:20}.nav button{border:0;background:transparent;color:var(--ink-soft);border-radius:12px;padding:6px 2px 8px;font-size:var(--fs-xs);font-weight:650;min-height:var(--nav-h);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px;letter-spacing:.01em}.nav button .nav-icon{font-size:clamp(1rem,.9rem + .8vw,1.25rem);line-height:1}.nav button.active{background:#0f3d3e1a;color:var(--teal)}.study-shell{display:flex;flex-direction:column;gap:12px;min-height:100%}.study-body{display:flex;flex-direction:column;gap:12px;flex:1}.study-actions{position:sticky;bottom:0;margin:0 -2px;padding:10px 2px 4px;background:linear-gradient(to top,var(--paper) 55%,rgba(243,240,232,0));z-index:5}.enunciado{font-family:var(--display);font-size:var(--fs-display);line-height:1.28;letter-spacing:-.02em;margin:0}.meta-row{display:flex;flex-wrap:wrap;align-items:center;gap:8px;color:var(--ink-soft);font-size:var(--fs-sm)}.chip{display:inline-flex;align-items:center;max-width:100%;padding:5px 10px;border-radius:999px;background:#0f3d3e14;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.session-pill{margin-left:auto}.options{display:flex;flex-direction:column;gap:8px}.option{display:grid;grid-template-columns:40px 1fr;gap:12px;align-items:center;text-align:left;width:100%;border:1.5px solid var(--line);background:#ffffffb8;border-radius:14px;padding:12px;min-height:var(--tap);transition:border-color .15s ease,background .15s ease,transform .1s ease}.option:active{transform:scale(.985)}.option.selected{border-color:var(--teal-bright);background:#1a6b6d1a;box-shadow:inset 0 0 0 1px #1a6b6d33}.option-letter{width:clamp(36px,10vw,44px);height:clamp(36px,10vw,44px);border-radius:12px;display:grid;place-items:center;font-weight:700;font-size:var(--fs-lg);background:#0f3d3e14;color:var(--teal);flex-shrink:0}.option-text{font-size:var(--fs-md);line-height:1.35}.primary,.secondary,.danger{border:0;border-radius:14px;min-height:var(--tap);padding:14px 16px;font-weight:650;width:100%}.primary{background:var(--teal);color:#f7f4ec;font-size:var(--fs-lg)}.primary:disabled{opacity:.4}.secondary{background:#ffffff8c;border:1.5px solid var(--line);color:var(--ink)}.danger{background:var(--bad-bg);color:var(--bad)}.banner{border-radius:14px;padding:14px 16px;font-weight:750;font-size:var(--fs-xl);text-align:center;animation:rise .28s ease both}.banner.ok{background:var(--ok-bg);color:var(--ok)}.banner.bad{background:var(--bad-bg);color:var(--bad)}@keyframes rise{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.review-list{display:flex;flex-direction:column;gap:8px}.review-item{border-radius:14px;padding:12px;border:1.5px solid var(--line);background:#ffffffa6;animation:rise .3s ease both}.review-item.correct{background:var(--ok-bg);border-color:#1f7a4c59}.review-item.chosen-wrong{background:var(--bad-bg);border-color:#b4231859}.review-item.other-wrong{background:var(--warn-bg);border-color:#9a670047}.review-head{display:flex;flex-direction:column;gap:2px;margin-bottom:6px;font-weight:700;font-size:var(--fs-md)}.review-label{font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:.04em;opacity:.85}.review-body{margin:0;color:var(--ink);font-size:var(--fs-md);line-height:1.35}.review-why{margin:8px 0 0;color:var(--ink-soft);font-size:var(--fs-sm);line-height:1.4}.stats-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px}.stat{padding:14px 12px;border-radius:14px;background:#fff9;border:1px solid var(--line);min-height:76px}.stat-value{font-family:var(--display);font-size:var(--fs-stat);color:var(--teal);line-height:1}.stat-label{margin-top:6px;font-size:var(--fs-sm);color:var(--ink-soft)}.section-title{font-family:var(--display);font-size:var(--fs-xl);margin:4px 0 0}.form{display:flex;flex-direction:column;gap:12px;padding-bottom:8px}.field{display:flex;flex-direction:column;gap:6px}.field label{font-size:var(--fs-sm);font-weight:650;color:var(--ink-soft)}.field input,.field textarea,.field select{width:100%;border:1.5px solid var(--line);border-radius:12px;padding:14px 12px;min-height:var(--tap);background:#ffffffc7;color:var(--ink);appearance:none}.field textarea{min-height:88px;resize:vertical}.muted{color:var(--ink-soft);font-size:var(--fs-sm);margin:0}.empty{padding:40px 12px;text-align:center;color:var(--ink-soft)}.stack{display:flex;flex-direction:column;gap:10px}.list-item{display:flex;flex-direction:column;gap:8px;padding:12px 0;border-bottom:1px solid var(--line)}.row-actions{display:grid;grid-template-columns:1fr;gap:8px}@media(min-width:380px){.row-actions{grid-template-columns:repeat(3,1fr)}}.toast{position:fixed;left:50%;bottom:calc(var(--nav-h) + var(--safe-b) + 18px);transform:translate(-50%);background:var(--ink);color:#f7f4ec;padding:12px 16px;border-radius:999px;font-size:var(--fs-sm);z-index:30;animation:rise .2s ease both;width:min(420px,calc(100% - 24px));text-align:center;pointer-events:none}.lock-screen{height:100dvh;height:100svh;width:100%;max-width:480px;margin:0 auto;display:flex;align-items:center;padding:max(16px,var(--safe-t)) max(16px,var(--safe-r)) max(16px,var(--safe-b)) max(16px,var(--safe-l))}.lock-card{width:100%;display:flex;flex-direction:column;gap:14px}.lock-error{margin:0;color:var(--bad);font-size:var(--fs-sm);font-weight:650}@media(min-width:481px){body{display:flex;justify-content:center}.app{border-inline:1px solid var(--line);box-shadow:0 0 0 12px #10242608}.nav{margin:0;border-radius:16px 16px 0 0}}