:root{--bg-android-blue: #9cbdfc;--bg-sidebar-blue: #5587e0;--bg-tools-blue: #4679d6;--bg-drawer-blue: #366ac7;--bg-chalkboard: #2a6a39}*{margin:0;padding:0;box-sizing:border-box;user-select:none;-webkit-user-select:none;touch-action:none}html,body{width:100vw;height:100vh;overflow:hidden;background-color:#000;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Arial,sans-serif}#app{width:100vw;height:100vh;position:relative;overflow:hidden;background:var(--bg-android-blue)}.home-screen{width:100%;height:100%;position:relative;background-image:url(/assets/drawable/notebook_1_by_marii85.jpg);background-size:cover;background-position:center;overflow:hidden}.home-top-bar{position:absolute;top:14px;right:18px;display:flex;gap:10px;z-index:100}.home-settings-btn{background:#ffffffe6;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border:1.5px solid rgba(0,0,0,.15);border-radius:20px;padding:8px 16px;font-size:1rem;font-weight:600;color:#1a3b70;cursor:pointer;display:flex;align-items:center;gap:8px;box-shadow:0 4px 12px #00000026;transition:transform .15s ease,background .15s ease,box-shadow .15s ease}.home-settings-btn:hover{transform:scale(1.05);background:#fff;box-shadow:0 6px 16px #00000038}.home-cover-canvas-container{position:absolute;top:2%;left:2%;width:46%;height:52%;pointer-events:none;display:flex;align-items:center;justify-content:flex-start}#home-cover-canvas{width:100%;height:100%;object-fit:contain}.home-bottom-left{position:absolute;bottom:24px;left:24px;display:flex;flex-direction:row;align-items:center;gap:24px;z-index:50}.home-parent-btn{background:none;border:none;cursor:pointer;padding:0;outline:none;transition:transform .15s ease}.home-parent-btn:hover{transform:scale(1.12)}.home-parent-btn img{height:48px;width:auto;display:block}.home-copyright{display:block;text-decoration:none;cursor:pointer;transition:transform .2s ease,opacity .2s ease}.home-copyright:hover{transform:scale(1.06);opacity:.9}.home-copyright img{height:36px;width:auto;display:block}.home-puzzle-wheel-container{position:absolute;top:50%;right:6%;transform:translateY(-50%);width:min(520px,76vh);height:min(520px,76vh);display:flex;align-items:center;justify-content:center;cursor:pointer}.puzzle-wheel-disc-bg{position:absolute;top:6%;left:6%;width:88%;height:88%;border-radius:50%;background:radial-gradient(circle at center,#fff,#fff 70%,#f4f4f4);box-shadow:0 10px 30px #0003;pointer-events:none}.puzzle-piece{position:absolute;top:0;left:0;width:100%;height:100%;pointer-events:none;transform-origin:center center;transition:transform .2s cubic-bezier(.2,.9,.3,1.1),opacity .2s ease,filter .2s ease}.puzzle-piece.active{transform:scale(1.06);z-index:10;opacity:1!important;filter:brightness(1.1) drop-shadow(0 8px 20px rgba(0,0,0,.25))}.puzzle-piece.dimmed{opacity:.88;filter:brightness(.98);transform:scale(1)}.puzzle-piece img{width:100%;height:100%;object-fit:contain;display:block}.make-choice-screen{width:100%;height:100%;display:flex;background-color:var(--bg-android-blue);overflow:hidden}.mc-sidebar{display:flex;height:100%;background:#6495ed;border-right:2px solid rgba(0,0,0,.2);z-index:50;box-shadow:3px 0 10px #00000026;position:relative}.mc-col-thumbs{width:72px;height:100%;overflow-y:auto;overflow-x:hidden;background:var(--bg-sidebar-blue);display:flex;flex-direction:column;align-items:center;padding:4px 0;gap:4px}.mc-col-thumbs::-webkit-scrollbar{width:4px}.mc-col-thumbs::-webkit-scrollbar-thumb{background:#fff6}.mc-thumb-item{width:64px;height:64px;background:var(--bg-chalkboard);border:1.5px solid rgba(255,255,255,.6);border-radius:4px;display:flex;align-items:center;justify-content:center;cursor:pointer;overflow:hidden;flex-shrink:0;transition:transform .1s ease,border-color .1s ease}.mc-thumb-item:hover{transform:scale(1.06);border-color:gold}.mc-thumb-item.active{border-color:#f33;box-shadow:0 0 8px #ff3232cc}.mc-thumb-item img{width:100%;height:100%;object-fit:cover}.mc-col-tools{width:56px;height:100%;background:var(--bg-tools-blue);display:flex;flex-direction:column;align-items:center;padding:4px 0;gap:6px;overflow-y:auto}.mc-tool-btn{width:44px;height:44px;background:none;border:none;border-radius:4px;cursor:pointer;padding:2px;display:flex;align-items:center;justify-content:center;flex-shrink:0;transition:transform .1s ease,background .1s ease}.mc-tool-btn:hover{transform:scale(1.12);background:#fff3}.mc-tool-btn.active{background:#fc0;box-shadow:0 0 8px #ffcc00e6}.mc-tool-btn img{max-width:100%;max-height:100%;object-fit:contain}.mc-drawer{position:absolute;top:0;left:128px;width:60px;height:100%;background:var(--bg-drawer-blue);border-right:2px solid rgba(0,0,0,.25);box-shadow:4px 0 12px #0003;display:flex;flex-direction:column;align-items:center;padding:6px 0;gap:6px;overflow-y:auto;z-index:55;animation:slideDrawer .15s ease-out}@keyframes slideDrawer{0%{transform:translate(-20px);opacity:0}to{transform:translate(0);opacity:1}}.mc-drawer-item{width:46px;height:46px;background:#ffffff26;border:1.5px solid rgba(255,255,255,.4);border-radius:6px;cursor:pointer;display:flex;align-items:center;justify-content:center;padding:2px;transition:transform .1s ease,border-color .1s ease;flex-shrink:0}.mc-drawer-item:hover{transform:scale(1.12);border-color:gold}.mc-drawer-item.active{border-color:#f33;background:#fff6;box-shadow:0 0 6px #fffc}.mc-drawer-item 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img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;display:block}.app-top-header{position:absolute;top:10px;left:154px;right:14px;height:48px;display:flex;align-items:center;justify-content:space-between;z-index:60;pointer-events:none}.app-top-header>*{pointer-events:auto}.header-left-group,.header-right-group{display:flex;align-items:center;gap:8px}.app-nav-btn{height:40px;background:#ffffffe6;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);color:#1a4d2b;border:1.5px solid rgba(26,77,43,.25);border-radius:20px;padding:0 14px;font-family:inherit;font-weight:700;font-size:.95rem;cursor:pointer;display:flex;align-items:center;gap:6px;box-shadow:0 4px 10px #00000026;transition:transform .15s ease,background .15s ease,box-shadow .15s ease}.app-nav-btn:hover{transform:translateY(-2px);background:#fff;box-shadow:0 6px 14px #00000038;border-color:#2a6a39}.app-nav-btn:active{transform:translateY(1px)}.app-nav-btn .nav-icon{font-size:1.15rem;display:flex;align-items:center}.app-category-badge{background:#1a4d2bd9;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);color:#fff;border:1.5px solid rgba(255,255,255,.4);border-radius:20px;padding:6px 18px;font-weight:800;font-size:1.05rem;box-shadow:0 4px 12px #0003;display:flex;align-items:center;gap:8px}.exercise-pagination{background:#ffffffeb;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border:1.5px solid rgba(26,77,43,.3);border-radius:22px;padding:3px 8px;display:flex;align-items:center;gap:10px;box-shadow:0 4px 12px #0000002e}.pagination-arrow{width:34px;height:34px;border-radius:50%;border:none;background:#2a6a39;color:#fff;font-size:.9rem;font-weight:700;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:transform .15s ease,background .15s ease}.pagination-arrow:hover:not(:disabled){transform:scale(1.15);background:#1a4d2b}.pagination-arrow:disabled{opacity:.3;cursor:not-allowed}.pagination-label{font-weight:800;font-size:1.1rem;color:#1a4d2b;min-width:40px;text-align:center}.mc-top-back-btn{display:none}.challenge-workspace{width:100%;height:100%;display:flex;position:relative;background:var(--bg-android-blue);overflow:hidden}.challenge-canvas-container{flex:1;height:100%;position:relative;display:flex;align-items:center;justify-content:center;padding:58px 16px 14px;box-sizing:border-box}#active-challenge-canvas{max-width:100%;max-height:100%;width:100%;height:100%;display:block}.challenge-top-actions{display:none}.challenge-action-btn{width:44px;height:44px;background:#00000059;border:none;border-radius:6px;cursor:pointer;display:flex;align-items:center;justify-content:center;padding:4px;transition:background .15s ease,transform .1s 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ease}.dialog-close-btn:hover{background:#1449aa}.lang-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;margin-bottom:1.5rem}.lang-option-btn{background:#f0f4fc;border:2px solid #ccd7ee;border-radius:8px;padding:10px 14px;font-size:1rem;font-weight:600;color:#1a3b70;cursor:pointer;display:flex;align-items:center;gap:8px;transition:all .15s ease}.lang-option-btn:hover{background:#dbe7fc;border-color:#6495ed;transform:translateY(-2px)}.lang-option-btn.active{background:#2a6a39;border-color:#1a4d2b;color:#fff}.settings-section-title{font-size:1.05rem;font-weight:700;color:#222;margin:1rem 0 .6rem}.settings-checkbox-card{display:flex;align-items:flex-start;gap:12px;background:#f7f9fc;border:1.5px solid #dce4f2;padding:12px 16px;border-radius:8px;margin-bottom:1.5rem;cursor:pointer}.settings-checkbox-card input[type=checkbox]{width:20px;height:20px;margin-top:2px;accent-color:#2a6a39;cursor:pointer}.settings-checkbox-info{display:flex;flex-direction:column;gap:2px}.settings-checkbox-title{font-weight:600;color:#1a3b70;font-size:.95rem}.settings-checkbox-desc{font-size:.85rem;color:#666}.sw-update-toast{position:fixed;bottom:20px;left:50%;transform:translate(-50%);background:#1a3b70;color:#fff;padding:12px 24px;border-radius:30px;box-shadow:0 10px 25px #0006;display:flex;align-items:center;gap:16px;z-index:300;animation:slideUp .3s ease-out;border:1.5px solid rgba(255,255,255,.3)}@keyframes slideUp{0%{transform:translate(-50%,40px);opacity:0}to{transform:translate(-50%);opacity:1}}.sw-update-btn{background:#fc0;color:#000;border:none;font-weight:700;padding:6px 14px;border-radius:20px;cursor:pointer;transition:transform .15s ease}.sw-update-btn:hover{transform:scale(1.08)}