:root{--primary: #7B1FA2;--accent: #9C27B0;--bg: #F3E5F5;--soft1: #F8EAFB;--soft2: #FCE4EC;--dark: #2E2E2E;--card-bg: #ffffff;--text-main: #1f2937;--solution-bg: #f8f5ff;--quick-nav-bg: #faf7ff;--quick-nav-border: #e9d5ff;--btn-prev-bg: #eee;--btn-prev-text: #555;--btn-prev-hover-bg: #e0e0e0;--glass-bg: rgba(255, 255, 255, .95);--glass-border: rgba(255, 255, 255, .2);--shadow-lg: 0 10px 30px -5px rgba(0, 0, 0, .1)}body.dark-mode-mode{--bg: #121212;--card-bg: #1e1e1e;--text-main: #e0e0e0;--soft1: #3e2744;--soft2: #422833;--solution-bg: #252525;--quick-nav-bg: #1e1e1e;--quick-nav-border: #333;--btn-prev-bg: #333;--btn-prev-text: #ddd;--btn-prev-hover-bg: #444;--glass-bg: rgba(30, 30, 30, .95);--glass-border: rgba(255, 255, 255, .05);--shadow-lg: 0 10px 30px -5px rgba(0, 0, 0, .5)}*{margin:0;padding:0;box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:80px}body{font-family:Segoe 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rgba(142,68,173,.1);position:relative;min-height:auto!important;height:auto!important;display:flex!important;flex-direction:column!important;justify-content:flex-start!important;align-items:center!important;gap:.5rem!important}body[data-exercise] .hero>*{position:relative!important;z-index:2;width:100%;max-width:800px;margin:0 auto!important;transform:none!important;grid-area:auto!important}body[data-exercise] .hero .breadcrumb{margin-bottom:.5rem!important}.hero-buttons{display:flex;justify-content:center;gap:15px;margin-top:1.5rem;flex-wrap:wrap}body[data-exercise] .hero-buttons .btn,.hero-buttons .btn{display:inline-flex!important;width:auto!important;min-width:120px;max-width:200px;padding:10px 24px!important;margin:0!important;font-size:.95rem!important;line-height:1.5!important;height:auto!important;border-radius:50px!important;text-transform:none!important;letter-spacing:normal!important;align-items:center;justify-content:center}@media(max-width:768px){.hero,body[data-exercise] 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.nav-btn{flex:1}.btn-prev{background:var(--quick-nav-bg);color:var(--text-main);border:2px solid var(--quick-nav-border)}.btn-next{background:var(--primary);color:#fff;box-shadow:0 4px 15px #7b1fa24d}.btn-prev:hover{background:var(--btn-prev-hover-bg)}.btn-next:hover{transform:translateY(-2px)}.nav-btn:focus-visible{outline:3px solid var(--primary);outline-offset:2px}.floating-controls{position:fixed;bottom:90px;left:20px;z-index:990;display:flex;flex-direction:column;align-items:flex-start;gap:10px;padding:8px 12px;background:var(--glass-bg);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border:1px solid var(--glass-border);border-radius:50px;box-shadow:var(--shadow-lg);transition:all .3s ease}@media(max-width:480px){.back-btn-floating span{display:none}.back-btn-floating i{font-size:1.2rem;margin:0}.back-btn-floating{padding:10px;border-radius:50%;width:40px;height:40px;justify-content:center}}.back-btn-floating{background:#fff;color:var(--primary);width:50px;height:50px;border-radius:50%;text-decoration:none;font-weight:600;display:flex;align-items:center;justify-content:center;transition:all .2s;box-shadow:0 4px 15px #00000026}.back-btn-floating i{font-size:1.2rem}.back-btn-floating span{display:none}.back-btn-floating:hover{background:var(--primary);color:#fff;transform:scale(1.1)}.theme-toggle-btn{width:40px;height:40px;border-radius:50%;background:var(--primary);color:#fff;border:none;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:.3s;font-size:1.2rem}.theme-toggle-btn:hover{transform:scale(1.1);box-shadow:0 4px 15px #7b1fa266}.theme-toggle-btn:focus-visible{outline:2px solid rgba(123,31,162,.5);outline-offset:2px}body.dark-mode-mode .back-btn-floating{color:#e0e0e0}body.dark-mode-mode 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2px!important}.breadcrumb a,.breadcrumb span,.exercise-breadcrumb a{display:inline-block!important;white-space:normal!important}}.q-table-container{overflow-x:auto;margin:1.5rem 0;border-radius:12px;box-shadow:0 4px 15px #0000000d;border:1px solid rgba(0,0,0,.05)}.q-table{width:100%;border-collapse:collapse;font-size:.95rem;background:var(--card-bg);min-width:max-content}.q-table th,.q-table td{padding:12px 16px;border:1px solid rgba(0,0,0,.08);text-align:center}.q-table th{background:var(--soft1);color:var(--primary);font-weight:600}.q-table tr:nth-child(2n){background:#00000005}body.dark-mode-mode .q-table-container{border-color:#ffffff1a;box-shadow:0 4px 15px #0003}body.dark-mode-mode .q-table{background:#1e1e1e}body.dark-mode-mode .q-table th,body.dark-mode-mode .q-table td{border-color:#ffffff1a}body.dark-mode-mode .q-table th{background:#333;color:#ddd}body.dark-mode-mode .q-table tr:nth-child(2n){background:#ffffff0d}.quick-nav{display:flex;gap:10px;overflow-x:auto;padding:10px 5px 20px;margin-bottom:2rem;scrollbar-width:thin;scrollbar-color:var(--primary) transparent}.quick-nav a{padding:8px 16px;background:var(--card-bg);border:1px solid rgba(0,0,0,.1);border-radius:50px;text-decoration:none;color:var(--text-main);font-weight:600;font-size:.9rem;white-space:nowrap;box-shadow:0 2px 4px #0000000d;transition:all .2s}.quick-nav a:hover{background:var(--primary);color:#fff;border-color:var(--primary);transform:translateY(-2px)}body.dark-mode-mode .quick-nav a{background:var(--soft1);border-color:#ffffff1a}.section-title{display:flex;align-items:center;gap:12px;color:var(--text-main);margin:2rem 0 1.5rem;font-size:1.5rem;font-weight:700;padding-bottom:10px;border-bottom:2px solid rgba(142,68,173,.2)}.section-title i{color:var(--primary)}.question-card{background:var(--card-bg);border-radius:12px;margin-bottom:1.5rem;box-shadow:0 4px 15px #0000000d;border:1px solid rgba(0,0,0,.08);overflow:hidden;transition:transform .2s}.question-card:hover{transform:translateY(-2px)}body.dark-mode-mode .question-card{border-color:#ffffff1a;box-shadow:0 4px 15px #0003}.question-header{padding:1.5rem}.q-badge{display:inline-block;background:var(--soft2);color:var(--primary);font-size:.75rem;font-weight:800;padding:4px 10px;border-radius:4px;margin-bottom:10px;text-transform:uppercase;letter-spacing:.5px}body.dark-mode-mode .q-badge{background:#9c27b033;color:#e0e0e0}.question-text{font-weight:600;font-size:1.1rem;color:var(--text-main);line-height:1.6}details{border-top:1px solid rgba(0,0,0,.08)}body.dark-mode-mode details{border-color:#ffffff1a}summary{padding:1rem 1.5rem;cursor:pointer;font-weight:600;color:var(--primary);background:var(--soft1);display:flex;align-items:center;justify-content:space-between;list-style:none;transition:background .2s}summary:hover{background:#8e44ad1a}summary::-webkit-details-marker{display:none}summary:after{content:"\f078";font-family:"Font Awesome 6 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