:root{--green: #58CC02;--green-dark: #46a302;--blue: #1CB0F6;--blue-dark: #1899d6;--orange: #FF9600;--red: #FF4B4B;--red-soft: #FFF0F0;--purple: #CE82FF;--yellow: #FFC800;--bg: #FFFFFF;--bg-secondary: #F7F7F7;--text: #3C3C3C;--text-secondary: #777777;--text-light: #AFAFAF;--border: #E5E5E5;--shadow: rgba(0, 0, 0, .08);--radius-sm: 8px;--radius: 12px;--radius-lg: 16px;--radius-xl: 24px;--btn-height: 56px;--card-padding: 20px;--font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--font-mono: "SF Mono", "Fira Code", monospace;--ease: cubic-bezier(.4, 0, .2, 1);--duration: .2s}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;-webkit-text-size-adjust:100%;-webkit-tap-highlight-color:transparent}body{font-family:var(--font);color:var(--text);background:var(--bg);line-height:1.5;overflow-x:hidden;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}#app{height:100dvh;display:flex;flex-direction:column;overflow:hidden}button{font:inherit;cursor:pointer;border:none;background:none;-webkit-user-select:none;user-select:none}a{color:inherit;text-decoration:none}img,svg{display:block;max-width:100%}body{overscroll-behavior-y:contain}.screen{flex:1;display:flex;flex-direction:column;max-width:600px;margin:0 auto;width:100%;padding:16px;padding-top:env(safe-area-inset-top,16px);padding-bottom:0;min-height:0}.screen-header{display:flex;align-items:center;justify-content:space-between;padding:8px 0 16px;gap:12px}.screen-title{font-size:24px;font-weight:800;color:var(--text)}.screen-body{flex:1;display:flex;flex-direction:column;gap:16px;overflow-y:auto;min-height:0}.screen-footer{padding:16px 0;display:flex;flex-direction:column;gap:8px}.screen-footer-sticky{flex-shrink:0;display:flex;flex-direction:column;gap:8px;padding:10px 0;border-top:2px solid var(--border);background:var(--bg)}.nav-bar{flex-shrink:0;display:flex;justify-content:space-around;align-items:center;padding:8px 0;padding-bottom:max(8px,env(safe-area-inset-bottom));border-top:2px solid var(--border);background:var(--bg)}.nav-item{display:flex;flex-direction:column;align-items:center;gap:2px;padding:4px 16px;border-radius:var(--radius);transition:background var(--duration) var(--ease);font-size:11px;color:var(--text-secondary);font-weight:600}.nav-item.active{color:var(--blue)}.nav-item svg{width:28px;height:28px}.center{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:16px}@media(min-width:480px){.screen{padding:24px}}.btn{display:flex;align-items:center;justify-content:center;min-height:var(--btn-height);padding:12px 24px;border-radius:var(--radius-lg);font-size:16px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;transition:all var(--duration) var(--ease);position:relative}.btn-primary{background:var(--green);color:#fff;box-shadow:0 4px 0 var(--green-dark)}.btn-primary:active{transform:translateY(2px);box-shadow:0 2px 0 var(--green-dark)}.btn-secondary{background:#fff;color:var(--blue);border:2px solid var(--border);box-shadow:0 4px 0 var(--border)}.btn-secondary:active{transform:translateY(2px);box-shadow:0 2px 0 var(--border)}.btn-option{background:#fff;color:var(--text);border:2px solid var(--border);border-radius:var(--radius);min-height:48px;padding:12px 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.4s var(--ease);min-width:16px}.search-input{width:100%;padding:12px 16px;border:2px solid var(--border);border-radius:12px;font-size:16px;font-family:inherit;outline:none;margin:0 0 4px;box-sizing:border-box;background:var(--bg);color:var(--text)}.search-input:focus{border-color:var(--green)}.category-header{display:flex;align-items:center;gap:8px;font-size:16px;font-weight:800;color:var(--text);padding:8px 0 4px}.category-count{font-size:14px;background:var(--bg-secondary);padding:2px 8px;border-radius:10px;color:var(--text-secondary);font-weight:600}.xp-badge{display:inline-flex;align-items:center;justify-content:center;text-align:center;gap:4px;padding:4px 12px;background:var(--yellow);color:#8a6d00;font-weight:800;font-size:14px;border-radius:20px}.streak-badge{display:inline-flex;align-items:center;justify-content:center;text-align:center;gap:4px;padding:4px 12px;background:var(--orange);color:#fff;font-weight:800;font-size:14px;border-radius:20px}.skill-node{width:64px;height:64px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:800;font-size:14px;cursor:pointer;transition:all var(--duration) var(--ease);border:3px solid;position:relative}.skill-node.locked{background:var(--bg-secondary);border-color:var(--border);color:var(--text-light);cursor:not-allowed;opacity:.6}.skill-node.available{background:#fff;border-color:var(--blue);color:var(--blue);box-shadow:0 4px 12px #1cb0f64d}.skill-node.available:active{transform:scale(.95)}.skill-node.mastered{background:var(--green);border-color:var(--green-dark);color:#fff}.skill-node.in-progress{background:#fff;border-color:var(--orange);color:var(--orange)}.skill-node.stage-review{border-style:dashed;box-shadow:0 4px 12px 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var(--border);border-radius:var(--radius);font-weight:600;cursor:grab;touch-action:none;-webkit-user-select:none;user-select:none;transition:box-shadow var(--duration) var(--ease)}.drag-item:active,.drag-item.dragging{cursor:grabbing;box-shadow:0 8px 24px var(--shadow);z-index:10}.drop-zone{min-height:48px;border:2px dashed var(--border);border-radius:var(--radius);display:flex;align-items:center;justify-content:center;padding:8px;transition:all var(--duration) var(--ease)}.drop-zone.active{border-color:var(--blue);background:#f0f9ff}.drop-zone.filled{border-style:solid;border-color:var(--green);background:#e8f8e0}.diagram-container{width:100%;aspect-ratio:4 / 3;background:var(--bg-secondary);border-radius:var(--radius-lg);border:2px solid var(--border);overflow:hidden;touch-action:none}.diagram-container svg{width:100%;height:100%}.kbd-hint{display:inline-flex;align-items:center;justify-content:center;min-width:22px;height:22px;padding:0 5px;background:var(--bg-secondary);border:1px solid var(--border);border-radius:4px;font-size:12px;font-weight:700;color:var(--text-light);font-family:var(--font-mono);line-height:1;flex-shrink:0;box-shadow:0 1px 0 var(--border);margin-right:8px;pointer-events:none}.btn-option .kbd-hint,.drag-item .kbd-hint{position:absolute;left:10px;top:50%;transform:translateY(-50%);margin-right:0}.btn-option:has(.kbd-hint),.drag-item:has(.kbd-hint){padding-left:40px;position:relative}.kbd-hint-inline{position:static!important;transform:none!important;margin-right:6px}.exercise-img-wrap{margin-bottom:12px;text-align:center}.exercise-img{max-width:100%;height:auto;border-radius:var(--radius);border:1px solid var(--border)}.exercise-chart-wrap{margin-bottom:12px;border-radius:var(--radius);border:1px solid var(--border);padding:8px;background:#fff}.exercise-area{flex:1;display:flex;flex-direction:column;overflow-y:auto;min-height:0}.exercise-area>:last-child .btn-primary:last-child,.exercise-area>.btn-primary:last-child{position:sticky;bottom:0;z-index:1}.exercise-icon-wrap{display:flex;justify-content:center;margin-bottom:8px}.exercise-icon{width:48px;height:48px;object-fit:contain;opacity:.7}@keyframes slideUp{0%{transform:translateY(100%);opacity:0}to{transform:translateY(0);opacity:1}}@keyframes slideInRight{0%{transform:translate(100%);opacity:0}to{transform:translate(0);opacity:1}}@keyframes slideOutLeft{0%{transform:translate(0);opacity:1}to{transform:translate(-100%);opacity:0}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes fadeOut{0%{opacity:1}to{opacity:0}}@keyframes bounceIn{0%{transform:scale(.5);opacity:0}60%{transform:scale(1.1)}to{transform:scale(1);opacity:1}}@keyframes shake{0%,to{transform:translate(0)}20%{transform:translate(-8px)}40%{transform:translate(8px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}@keyframes floatUp{0%{transform:translateY(0);opacity:1}to{transform:translateY(-60px);opacity:0}}@keyframes pulse{0%,to{box-shadow:0 0 #1cb0f666}50%{box-shadow:0 0 0 12px #1cb0f600}}@keyframes scalePop{0%{transform:scale(1)}50%{transform:scale(1.2)}to{transform:scale(1)}}@keyframes shine{0%{transform:translate(-100%)}to{transform:translate(200%)}}.anim-slide-up{animation:slideUp .3s var(--ease)}.anim-slide-in{animation:slideInRight .3s var(--ease)}.anim-fade-in{animation:fadeIn .2s var(--ease)}.anim-bounce-in{animation:bounceIn .4s var(--ease)}.anim-shake{animation:shake .4s var(--ease)}.anim-float-xp{animation:floatUp 1s var(--ease) forwards;position:absolute;font-weight:800;color:var(--yellow);font-size:20px;pointer-events:none}.skill-node.available{animation:pulse 2s infinite}.combo-pop{animation:scalePop .3s var(--ease)}