:root{--bg-deep: #0a0b16;--bg-mid: #12142a;--bg-rise: #181a34;--glass-bg: rgba(255, 255, 255, .045);--glass-bg-strong: rgba(255, 255, 255, .07);--glass-border: rgba(255, 255, 255, .1);--glass-border-soft: rgba(255, 255, 255, .06);--violet: #8b7cff;--violet-dim: #5b4fc7;--cyan: #52e0e6;--coral: #ff8b7b;--coral-dim: #c65f52;--success: #4ade94;--danger: #ff6b7a;--text-hi: #f3f4fb;--text-mid: #b7bbd4;--text-dim: #7d8199;--radius-lg: 22px;--radius-md: 16px;--radius-sm: 10px;--shadow-float: 0 20px 60px -20px rgba(0, 0, 0, .6);--shadow-lift: 0 10px 30px -8px rgba(0, 0, 0, .5);--font-display: "Space Grotesk", "Inter", sans-serif;--font-body: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;--font-mono: "IBM Plex Mono", monospace;--ease-out: cubic-bezier(.16, 1, .3, 1)}*{box-sizing:border-box}html{-webkit-tap-highlight-color:transparent}body{margin:0;min-height:100vh;background:radial-gradient(1100px 600px at 12% -10%,rgba(139,124,255,.16),transparent 60%),radial-gradient(900px 500px at 88% 0%,rgba(82,224,230,.12),transparent 55%),radial-gradient(1200px 800px at 50% 110%,rgba(139,124,255,.08),transparent 60%),linear-gradient(180deg,var(--bg-deep) 0%,var(--bg-mid) 55%,var(--bg-deep) 100%);background-attachment:fixed;color:var(--text-hi);font-family:var(--font-body);overflow-x:hidden}button{font-family:inherit}button:focus-visible,a:focus-visible,textarea:focus-visible,[tabindex]:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:6px}.sf-glass{background:linear-gradient(160deg,var(--glass-bg-strong),var(--glass-bg));border:1px solid var(--glass-border);border-radius:var(--radius-lg);backdrop-filter:blur(18px);-webkit-backdrop-filter:blur(18px);box-shadow:var(--shadow-float)}.sf-eyebrow{font-family:var(--font-mono);font-size:.72rem;letter-spacing:.14em;text-transform:uppercase;color:var(--text-dim)}.sf-app{position:relative;min-height:100vh;padding:0 20px 72px}.sf-decor{position:fixed;top:0;right:0;bottom:0;left:0;overflow:hidden;pointer-events:none;z-index:0}.sf-decor-shape{position:absolute;border-radius:28px;border:1px solid rgba(255,255,255,.08);background:linear-gradient(140deg,#8b7cff24,#52e0e60f);-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);transform-style:preserve-3d;will-change:transform}.sf-decor-shape.s1{width:150px;height:190px;top:8%;left:6%;transform:perspective(800px) rotateX(18deg) rotateY(-22deg) rotate(-6deg);animation:sf-float-a 16s ease-in-out infinite}.sf-decor-shape.s2{width:110px;height:110px;border-radius:50%;top:62%;left:3%;background:linear-gradient(140deg,#52e0e629,#8b7cff0a);animation:sf-float-b 20s ease-in-out infinite}.sf-decor-shape.s3{width:130px;height:160px;top:14%;right:7%;transform:perspective(800px) rotateX(-14deg) rotateY(20deg) rotate(8deg);animation:sf-float-c 18s ease-in-out infinite}.sf-decor-shape.s4{width:90px;height:90px;bottom:10%;right:10%;border-radius:20px;background:linear-gradient(140deg,#ff8b7b1f,#8b7cff0f);animation:sf-float-a 22s ease-in-out infinite reverse}@keyframes sf-float-a{0%,to{transform:perspective(800px) rotateX(18deg) rotateY(-22deg) rotate(-6deg) translateY(0)}50%{transform:perspective(800px) rotateX(10deg) rotateY(-14deg) rotate(-2deg) translateY(-24px)}}@keyframes sf-float-b{0%,to{transform:translateY(0) translate(0)}50%{transform:translateY(-30px) translate(14px)}}@keyframes sf-float-c{0%,to{transform:perspective(800px) rotateX(-14deg) rotateY(20deg) rotate(8deg) translateY(0)}50%{transform:perspective(800px) rotateX(-8deg) rotateY(12deg) rotate(4deg) translateY(20px)}}.sf-main{position:relative;z-index:1;max-width:760px;margin:0 auto}.sf-topbar{display:flex;align-items:center;justify-content:space-between;padding:28px 0 8px}.sf-brand{display:flex;align-items:center;gap:10px}.sf-brand-mark{width:30px;height:30px;border-radius:9px;background:linear-gradient(135deg,var(--violet),var(--cyan));position:relative;box-shadow:0 6px 18px -4px #8b7cff8c;transform:perspective(200px) rotateY(-18deg) rotateX(8deg)}.sf-brand-mark:after{content:"";position:absolute;top:6px;right:6px;bottom:6px;left:6px;border-radius:5px;background:#0a0b168c}.sf-brand-name{font-family:var(--font-display);font-weight:700;font-size:1.08rem;letter-spacing:-.01em}.sf-reset-btn{background:transparent;border:1px solid var(--glass-border);color:var(--text-mid);border-radius:999px;padding:8px 16px;font-size:.82rem;cursor:pointer;transition:border-color .2s var(--ease-out),color .2s var(--ease-out)}.sf-reset-btn:hover{border-color:var(--violet);color:var(--text-hi)}.sf-hero{text-align:center;padding:40px 0 8px}.sf-hero h1{font-family:var(--font-display);font-weight:700;font-size:clamp(1.9rem,5vw,2.7rem);line-height:1.15;letter-spacing:-.02em;margin:18px 0 14px;background:linear-gradient(120deg,#ffffff 30%,var(--cyan) 75%,var(--violet) 100%);-webkit-background-clip:text;background-clip:text;color:transparent}.sf-hero p{color:var(--text-mid);font-size:1.02rem;max-width:480px;margin:0 auto;line-height:1.55}.sf-hero-badge{display:inline-flex;align-items:center;gap:8px;padding:6px 14px;border-radius:999px;font-size:.75rem;color:var(--text-mid)}.sf-hero-badge .dot{width:6px;height:6px;border-radius:50%;background:var(--success);box-shadow:0 0 8px var(--success)}.sf-input-card{margin-top:34px;padding:22px;transition:box-shadow .3s var(--ease-out),border-color .3s var(--ease-out)}.sf-input-card:focus-within{border-color:#8b7cff80;box-shadow:var(--shadow-float),0 0 0 4px #8b7cff1f}.sf-textarea{width:100%;background:transparent;border:none;color:var(--text-hi);font-size:1.02rem;font-family:inherit;line-height:1.6;resize:vertical;min-height:120px}.sf-textarea::placeholder{color:var(--text-dim)}.sf-textarea:focus{outline:none}.sf-input-footer{display:flex;align-items:center;justify-content:flex-end;margin-top:14px;padding-top:14px;border-top:1px solid var(--glass-border-soft)}.sf-generate-btn{position:relative;display:inline-flex;align-items:center;gap:10px;border:none;border-radius:999px;padding:13px 26px;font-size:.96rem;font-weight:600;color:#0a0b16;background:linear-gradient(120deg,var(--cyan),var(--violet));cursor:pointer;box-shadow:0 12px 30px -10px #8b7cff8c;transition:transform .18s var(--ease-out),box-shadow .18s var(--ease-out)}.sf-generate-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 16px 36px -8px #8b7cffa6}.sf-generate-btn:active:not(:disabled){transform:translateY(0)}.sf-generate-btn:disabled{opacity:.45;cursor:not-allowed;box-shadow:none}.sf-generate-btn svg{width:16px;height:16px}.sf-examples{margin-top:22px}.sf-examples-label{text-align:center;margin-bottom:12px}.sf-chip-row{display:flex;flex-wrap:wrap;gap:9px;justify-content:center}.sf-chip{background:var(--glass-bg);border:1px solid var(--glass-border-soft);color:var(--text-mid);border-radius:999px;padding:9px 16px;font-size:.85rem;cursor:pointer;transition:border-color .2s var(--ease-out),color .2s var(--ease-out),transform .15s var(--ease-out)}.sf-chip:hover{border-color:var(--cyan);color:var(--text-hi);transform:translateY(-1px)}.sf-state-card{margin-top:36px;padding:46px 28px;text-align:center}.sf-state-icon{width:52px;height:52px;margin:0 auto 18px;border-radius:16px;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#8b7cff2e,#52e0e61a);border:1px solid var(--glass-border)}.sf-state-card h3{font-family:var(--font-display);font-size:1.15rem;margin:0 0 8px}.sf-state-card p{color:var(--text-mid);font-size:.94rem;max-width:340px;margin:0 auto;line-height:1.5}.sf-loading-orbit{position:relative;width:64px;height:64px;margin:0 auto 22px}.sf-loading-orbit .core{position:absolute;top:22px;right:22px;bottom:22px;left:22px;border-radius:50%;background:radial-gradient(circle,var(--cyan),var(--violet));filter:blur(1px);animation:sf-pulse 1.8s ease-in-out infinite}.sf-loading-orbit .ring{position:absolute;top:0;right:0;bottom:0;left:0;border-radius:50%;border:1.5px dashed rgba(139,124,255,.35);animation:sf-spin-slow 6s linear infinite}.sf-loading-orbit .particle{position:absolute;width:8px;height:8px;border-radius:50%;background:var(--cyan);top:-4px;left:50%;margin-left:-4px;box-shadow:0 0 10px var(--cyan);animation:sf-spin-slow 2.4s linear infinite}@keyframes sf-pulse{0%,to{transform:scale(.85);opacity:.7}50%{transform:scale(1.05);opacity:1}}@keyframes sf-spin-slow{0%{transform:rotate(0) translateY(0)}to{transform:rotate(360deg) translateY(0)}}.sf-loading-caption{font-family:var(--font-display);font-size:1.05rem;font-weight:600;margin-bottom:6px}.sf-state-card.is-error{border-color:#ff6b7a59}.sf-state-card.is-error .sf-state-icon{background:linear-gradient(135deg,#ff6b7a33,#ff8b7b14)}.sf-retry-btn{margin-top:20px;border:none;border-radius:999px;padding:11px 24px;font-weight:600;font-size:.9rem;color:var(--text-hi);background:var(--glass-bg-strong);border:1px solid var(--glass-border);cursor:pointer;transition:border-color .2s,transform .15s var(--ease-out)}.sf-retry-btn:hover{border-color:var(--danger);transform:translateY(-1px)}.sf-error-details{margin-top:14px;font-size:.75rem}.sf-error-details summary{cursor:pointer;color:var(--text-dim)}.sf-error-details pre{text-align:left;white-space:pre-wrap;word-break:break-word;color:var(--text-dim);background:#00000040;border-radius:var(--radius-sm);padding:10px;margin-top:8px;font-family:var(--font-mono);font-size:.72rem}.sf-dash-header{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin:30px 0 18px;flex-wrap:wrap}.sf-dash-topic{font-family:var(--font-display);font-size:1.4rem;font-weight:700;letter-spacing:-.01em}.sf-tabs{display:inline-flex;gap:4px;padding:4px;border-radius:999px;background:var(--glass-bg);border:1px solid var(--glass-border-soft);margin-bottom:26px}.sf-tab{border:none;background:transparent;color:var(--text-mid);border-radius:999px;padding:9px 20px;font-size:.88rem;font-weight:600;cursor:pointer;transition:color .2s var(--ease-out)}.sf-tab.active{color:#0a0b16;background:linear-gradient(120deg,var(--cyan),var(--violet))}.sf-deck{padding:28px 22px 24px}.sf-deck-meta{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.sf-progress-track{flex:1;height:4px;border-radius:4px;background:var(--glass-border-soft);margin:0 16px;overflow:hidden}.sf-progress-fill{height:100%;border-radius:4px;background:linear-gradient(90deg,var(--cyan),var(--violet));transition:width .35s var(--ease-out)}.sf-flip-stage{perspective:1600px;width:100%}.sf-flip-card{position:relative;width:100%;min-height:240px;cursor:pointer;transform-style:preserve-3d;transition:transform .6s var(--ease-out)}.sf-flip-card.flipped{transform:rotateY(180deg)}.sf-flip-card:hover:not(.flipped){transform:rotateY(-4deg) rotateX(2deg)}.sf-flip-face{position:absolute;top:0;right:0;bottom:0;left:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;border-radius:var(--radius-md);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:14px;padding:32px 26px;text-align:center;border:1px solid var(--glass-border);box-shadow:var(--shadow-lift)}.sf-flip-face.front{background:linear-gradient(155deg,rgba(139,124,255,.16),var(--bg-rise) 65%)}.sf-flip-face.back{background:linear-gradient(155deg,rgba(82,224,230,.14),var(--bg-rise) 65%);transform:rotateY(180deg)}.sf-flip-face .sf-eyebrow{color:var(--violet)}.sf-flip-face.back .sf-eyebrow{color:var(--cyan)}.sf-flip-text{font-family:var(--font-display);font-size:1.2rem;font-weight:600;line-height:1.5}.sf-flip-hint{color:var(--text-dim);font-size:.78rem}.sf-deck-controls{display:flex;align-items:center;justify-content:center;gap:14px;margin-top:22px}.sf-ctrl-btn{display:inline-flex;align-items:center;gap:6px;background:var(--glass-bg);border:1px solid var(--glass-border);color:var(--text-hi);border-radius:999px;padding:10px 20px;font-size:.88rem;font-weight:600;cursor:pointer;transition:border-color .2s,transform .15s var(--ease-out)}.sf-ctrl-btn:hover{border-color:var(--cyan);transform:translateY(-1px)}.sf-ctrl-btn.primary{background:linear-gradient(120deg,var(--cyan),var(--violet));color:#0a0b16;border:none}.sf-keyboard-hint{text-align:center;margin-top:14px;color:var(--text-dim);font-size:.74rem}.sf-keyboard-hint kbd{font-family:var(--font-mono);background:var(--glass-bg-strong);border:1px solid var(--glass-border);border-radius:4px;padding:1px 6px;margin:0 2px}.sf-quiz{padding:28px 22px 26px}.sf-quiz-question{font-family:var(--font-display);font-size:1.15rem;font-weight:600;line-height:1.5;margin:4px 0 22px}.sf-quiz-options{display:flex;flex-direction:column;gap:11px}.sf-quiz-option{display:flex;align-items:center;gap:12px;text-align:left;background:var(--glass-bg);border:1px solid var(--glass-border);color:var(--text-hi);border-radius:var(--radius-sm);padding:14px 16px;font-size:.94rem;cursor:pointer;transition:border-color .18s var(--ease-out),background .18s var(--ease-out),transform .12s var(--ease-out)}.sf-quiz-option:hover:not(:disabled){border-color:#8b7cff80;transform:translate(2px)}.sf-quiz-option .letter{width:26px;height:26px;flex-shrink:0;border-radius:8px;background:var(--glass-bg-strong);display:flex;align-items:center;justify-content:center;font-family:var(--font-mono);font-size:.74rem;color:var(--text-dim)}.sf-quiz-option.selected{border-color:var(--violet);background:#8b7cff1f}.sf-quiz-option.correct{border-color:var(--success);background:#4ade941f}.sf-quiz-option.correct .letter{background:var(--success);color:#0a0b16}.sf-quiz-option.incorrect{border-color:var(--danger);background:#ff6b7a1a}.sf-quiz-option.incorrect .letter{background:var(--danger);color:#0a0b16}.sf-quiz-option:disabled{cursor:default}.sf-quiz-feedback{margin-top:20px;padding-top:18px;border-top:1px solid var(--glass-border-soft);animation:sf-rise-in .3s var(--ease-out)}@keyframes sf-rise-in{0%{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}.sf-feedback-tag{display:inline-flex;align-items:center;gap:6px;font-weight:700;font-size:.92rem;margin-bottom:8px}.sf-feedback-tag.good{color:var(--success)}.sf-feedback-tag.bad{color:var(--danger)}.sf-quiz-explanation{color:var(--text-mid);font-size:.9rem;line-height:1.55;margin:0 0 18px}.sf-quiz-result{text-align:center;padding:12px 0 4px}.sf-score-ring{width:148px;height:148px;margin:6px auto 20px;border-radius:50%;display:flex;align-items:center;justify-content:center;position:relative}.sf-score-ring .fill{position:absolute;top:0;right:0;bottom:0;left:0;border-radius:50%;background:conic-gradient(var(--cyan) calc(var(--pct) * 1%),var(--glass-border) 0);-webkit-mask:radial-gradient(farthest-side,transparent calc(100% - 12px),#000 calc(100% - 11px));mask:radial-gradient(farthest-side,transparent calc(100% - 12px),#000 calc(100% - 11px))}.sf-score-ring .num{font-family:var(--font-display);font-size:1.9rem;font-weight:700;position:relative;z-index:1}.sf-score-ring .denom{font-size:.9rem;color:var(--text-dim);font-weight:500}.sf-score-breakdown{display:flex;justify-content:center;gap:22px;margin-bottom:22px;font-size:.88rem}.sf-score-breakdown .item{display:flex;align-items:center;gap:6px;color:var(--text-mid)}.sf-score-breakdown .swatch{width:8px;height:8px;border-radius:50%}.sf-score-breakdown .swatch.good{background:var(--success)}.sf-score-breakdown .swatch.bad{background:var(--danger)}.sf-retest-panel{margin-top:6px;padding:18px;border-radius:var(--radius-md);background:linear-gradient(155deg,rgba(255,139,123,.12),var(--glass-bg));border:1px solid rgba(255,139,123,.28)}.sf-retest-panel p{margin:0 0 14px;color:var(--text-mid);font-size:.9rem}.sf-retest-btn{border:none;border-radius:999px;padding:12px 24px;font-weight:700;font-size:.92rem;color:#0a0b16;background:linear-gradient(120deg,var(--coral),var(--violet));cursor:pointer;box-shadow:0 10px 26px -10px #ff8b7b80;transition:transform .15s var(--ease-out)}.sf-retest-btn:hover{transform:translateY(-1px)}.sf-perfect-tag{color:var(--success);font-weight:700;margin:4px 0 20px}@media (max-width: 640px){.sf-app{padding:0 14px 56px}.sf-hero{padding-top:20px}.sf-input-card{padding:16px}.sf-dash-header{flex-direction:column;align-items:flex-start}.sf-flip-face{padding:24px 18px}.sf-flip-text{font-size:1.05rem}.sf-decor-shape.s1,.sf-decor-shape.s3{opacity:.5;transform:scale(.7)!important}.sf-score-ring{width:128px;height:128px}}@media (max-width: 380px){.sf-generate-btn{width:100%;justify-content:center}.sf-input-footer{justify-content:stretch}.sf-deck-controls{flex-wrap:wrap}.sf-ctrl-btn{flex:1;justify-content:center}}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important;scroll-behavior:auto!important}.sf-flip-card{transition:none}.sf-decor-shape{animation:none!important}}