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var(--outline-variant);background:var(--surface-container-low)}.chat-main{display:flex;flex-direction:column;position:relative;background:var(--surface)}.chat-container{display:flex;flex-direction:column;height:100%;position:relative;background:var(--surface);flex:1;min-width:0}.scroll-bottom-btn{position:absolute;bottom:120px;right:2rem;width:48px;height:48px;border-radius:50%;background:var(--surface-container-lowest);border:1px solid var(--outline-variant);box-shadow:var(--shadow-ambient);color:var(--on-surface);cursor:pointer;display:flex;align-items:center;justify-content:center;z-index:101;opacity:0;pointer-events:none;transform:translateY(10px) scale(.9);transition:all .3s cubic-bezier(.34,1.56,.64,1)}.scroll-bottom-btn.visible{opacity:1;pointer-events:auto;transform:translateY(0) scale(1)}.scroll-progress-ring{position:absolute;top:0;left:0;transform:rotate(-90deg)}.scroll-progress-bg{stroke:rgba(var(--primary-rgb),.03);stroke-width:2.5}.scroll-progress-indicator{stroke:var(--primary);stroke-width:2.5;transition:stroke-dashoffset .1s}.scroll-arrow-icon{position:relative;z-index:2;display:flex;align-items:center;justify-content:center;color:var(--on-surface-variant);transition:color .2s}.scroll-bottom-btn:hover .scroll-arrow-icon{color:var(--primary)}.premium-chat .chat-toolbar{position:relative;z-index:10;background:var(--surface);border-top:1px solid var(--outline-variant);margin-top:auto;padding-bottom:var(--space-md)}.toggle-view-btn{display:flex;align-items:center;gap:.5rem;padding:.4rem .75rem;background:var(--surface-container-highest);border:1px solid var(--outline);border-radius:var(--radius-md);color:var(--on-surface);cursor:pointer;transition:all var(--transition-base);margin-left:auto;margin-right:1.5rem;position:relative;overflow:hidden}.toggle-view-btn:hover{background:var(--surface-bright);border-color:var(--primary)}.toggle-view-btn .sigma-icon{font-family:var(--font-primary);font-weight:700;color:var(--primary);font-size:1rem}.toggle-view-btn .label-xs{font-size:var(--fs-caption);font-weight:700;opacity:.7}.toggle-view-btn.alt{background:rgba(var(--primary-rgb),.08);border-color:var(--outline-variant)}.toggle-view-btn.alt:hover{background:rgba(var(--primary-rgb),.15)}.chat-toolbar-inner{max-width:800px;margin:0 auto;width:100%}.chat-input-container{display:flex;flex-direction:column;gap:var(--space-sm)}.chat-input-bar{background:var(--surface-container-lowest);border:1px solid var(--outline);border-radius:32px;padding:8px 8px 8px 16px;display:flex;align-items:center;gap:var(--space-sm);transition:all .2s cubic-bezier(.4,0,.2,1)}.chat-input-bar:focus-within{border-color:var(--primary);box-shadow:var(--focus-ring)}.chat-input-bar input{flex:1;min-width:0;background:transparent;border:none;color:var(--on-surface);font-size:var(--fs-body);padding:10px 4px;outline:none;font-family:var(--font-primary)}.chat-input-bar input::placeholder{color:var(--on-surface-variant);opacity:.6}.chat-input-left-actions,.chat-input-right-actions{display:flex;align-items:center;gap:4px;flex-shrink:0}.btn-icon-pill{width:40px;height:40px;display:flex;align-items:center;justify-content:center;border-radius:50%;border:none;background:transparent;color:var(--on-surface-variant);cursor:pointer;transition:all .2s;opacity:.7}.btn-icon-pill:hover{background:rgba(var(--primary-rgb),.05);color:var(--primary);opacity:1}.chat-send-btn-modern{width:40px;height:40px;display:flex;align-items:center;justify-content:center;border-radius:50%;border:none;background:var(--marigold);color:var(--on-marigold);cursor:pointer;transition:all .2s}.chat-send-btn-modern:hover{filter:brightness(.94)}.chat-send-btn-modern:focus-visible{outline:none;box-shadow:var(--focus-ring)}.chat-send-btn-modern:active{transform:scale(.95)}.chat-send-btn-modern svg{transform:rotate(0)}.math-helpers-bar{display:flex;justify-content:center;overflow-x:auto;scrollbar-width:none;padding:4px 0;opacity:.6;transition:opacity .3s}.math-helpers-bar:hover{opacity:1}.math-helpers-row{display:flex;gap:8px}.math-helper-btn{background:rgba(var(--primary-rgb),.03);border:1px solid var(--outline-variant);color:var(--on-surface-dim);padding:4px 12px;border-radius:12px;font-family:var(--font-primary);font-size:var(--fs-caption);cursor:pointer;transition:all .2s;white-space:nowrap}.math-helper-btn:hover{background:rgba(var(--primary-rgb),.1);color:var(--primary);border-color:var(--primary-container)}.chat-messages{flex:1;min-width:0;overflow-y:auto;padding:var(--space-2xl) var(--space-2xl) 64px;display:flex;flex-direction:column;gap:var(--space-2xl);width:100%;box-sizing:border-box}.calc-modal-mount{position:fixed;top:0;left:0;width:100vw;height:100vh;z-index:2000;pointer-events:none}.calc-modal-mount>*{pointer-events:auto;animation:calcPop .3s cubic-bezier(.34,1.56,.64,1);box-shadow:var(--shadow-ambient);border:1px solid var(--outline-variant)}.calc-groups{display:flex;flex-direction:column;gap:8px;margin-bottom:var(--space-lg)}.calc-group{background:rgba(var(--primary-rgb),.03);border:1px solid var(--outline-variant);border-radius:var(--radius-md);overflow:hidden}.calc-group summary{padding:var(--space-sm) var(--space-md);font-size:var(--fs-caption);font-weight:600;color:var(--primary);cursor:pointer;list-style:none;display:flex;justify-content:space-between;align-items:center;-webkit-user-select:none;user-select:none;background:rgba(var(--primary-rgb),.05)}.calc-group summary::-webkit-details-marker{display:none}.calc-group summary:after{content:"+";font-family:var(--font-primary);font-size:var(--fs-body)}.calc-group[open] summary:after{content:"−"}.calc-group-content{padding:var(--space-sm);display:grid;grid-template-columns:repeat(4,1fr);gap:6px;max-height:250px;overflow-y:auto;animation:calcGroupIn .2s ease}.calc-group-content .calc-btn{height:38px!important;font-size:var(--fs-caption)!important;border-radius:8px!important}@keyframes calcGroupIn{0%{opacity:0;transform:translateY(-5px)}to{opacity:1;transform:translateY(0)}}.calc-row-main{grid-column:span 4;display:grid;grid-template-columns:repeat(4,1fr)!important;gap:8px;margin-bottom:var(--space-md)}.chat-welcome-area{text-align:center;padding:10rem 2rem 6rem;width:100%}.welcome-label{color:var(--on-surface-dim);margin-bottom:.75rem}.welcome-headline{color:var(--on-surface-variant);font-weight:400;margin-bottom:2.5rem}.welcome-subtext{color:var(--on-surface-dim);margin-top:4rem;max-width:320px;margin-left:auto;margin-right:auto;opacity:.7}.chat-msg{max-width:85%;padding:var(--space-lg) var(--space-xl);border-radius:var(--radius-lg);animation:fadeIn .4s cubic-bezier(.4,0,.2,1);will-change:transform,opacity}.msg-body{min-height:1.5em;transition:all var(--transition-base)}.msg-text,.step-item,.formula-chip,.msg-question-minimal{animation:slideUp .3s ease-out;animation-fill-mode:both}@keyframes slideUp{0%{opacity:0;transform:translateY(4px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.chat-msg.user{background:var(--surface-container-high);align-self:flex-end;border-bottom-right-radius:var(--radius-sm)}.chat-msg.assistant{background:var(--surface-container-low);align-self:flex-start;border-bottom-left-radius:var(--radius-sm)}.chat-msg .msg-label{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--on-surface-dim);margin-bottom:var(--space-sm)}.chat-msg.assistant .msg-label{color:var(--on-surface-variant)}.chat-msg .msg-content{font-size:var(--fs-body);line-height:1.7;color:var(--on-surface)}.chat-msg .msg-steps{margin-top:var(--space-lg);display:flex;flex-direction:column;gap:var(--space-md)}.chat-msg .step{padding:var(--space-md) var(--space-lg);background:var(--surface-container-lowest);border-radius:var(--radius-md);font-size:var(--fs-body-sm);line-height:1.6}.chat-msg .step-number{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--primary);font-weight:600;margin-bottom:var(--space-xs)}.chat-msg .msg-question{margin-top:var(--space-lg);padding:var(--space-md) var(--space-lg);background:var(--surface-container-low);border:1px solid var(--outline-variant);border-radius:var(--radius-md);color:var(--on-surface);font-weight:500;font-size:var(--fs-body)}.premium-chat .send-btn{background:var(--marigold);color:var(--on-marigold);border:none;border-radius:var(--radius-md);width:32px;height:32px;display:flex;align-items:center;justify-content:center;cursor:pointer;transition:all var(--transition-fast)}.premium-chat .send-btn:hover{filter:brightness(.94)}.quick-questions{display:flex;flex-wrap:wrap;gap:var(--space-md);justify-content:center;max-width:850px;margin:0 auto}.chip-action.quick-q-btn{background:var(--surface-container-lowest);border:1px solid var(--outline-variant);color:var(--on-surface-variant);padding:var(--space-md) var(--space-xl);border-radius:var(--radius-full);font-size:var(--fs-body);font-weight:500;cursor:pointer;transition:all var(--transition-fast);display:flex;align-items:center;gap:var(--space-sm);white-space:nowrap}.chip-action.quick-q-btn:hover{background:var(--primary-container);color:var(--on-primary-container);border-color:var(--outline)}.msg-header-minimal{display:flex;align-items:center;gap:var(--space-sm);margin-bottom:var(--space-md);opacity:.6}.ai-sparkle-small{color:var(--primary)}.ai-name{font-family:var(--font-primary);font-size:var(--fs-caption)}.msg-steps-clean{display:flex;flex-direction:column;gap:var(--space-md);margin-bottom:var(--space-xl);border-left:2px solid var(--outline-variant);padding-left:var(--space-xl)}.step-item{display:flex;gap:var(--space-md);align-items:flex-start}.step-bullet{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--primary);opacity:.5;width:20px;flex-shrink:0;padding-top:2px}.step-content{font-size:var(--fs-body);line-height:1.7}.formula-chip-container{display:flex;flex-wrap:wrap;gap:var(--space-sm);margin:var(--space-lg) 0}.formula-chip{background:var(--surface-container-high);border:1px solid var(--outline-variant);padding:var(--space-sm) var(--space-lg);border-radius:var(--radius-full);font-family:var(--font-primary);font-size:var(--fs-label);color:var(--on-surface)}.msg-question-minimal{display:flex;align-items:flex-start;gap:var(--space-md);padding:var(--space-lg);background:rgba(var(--primary-rgb),.05);border-radius:var(--radius-lg);margin-top:var(--space-xl);border:1px solid var(--outline-variant)}.question-icon{color:var(--primary);flex-shrink:0;padding-top:2px}.question-text{font-size:var(--fs-body);font-weight:500;color:var(--on-surface);line-height:1.5}.formulas-used{margin-top:var(--space-lg);padding:var(--space-md) var(--space-lg);background:var(--correct-wash);border-radius:var(--radius-lg);border:1px solid color-mix(in srgb,var(--correct) 12%,transparent)}.formulas-label{font-size:var(--fs-caption);font-weight:600;color:var(--on-surface-dim);margin-bottom:var(--space-sm)}.formula-item{font-family:var(--font-primary);font-size:var(--fs-body);padding:var(--space-xs) 0;color:var(--on-surface);line-height:1.6}.msg-hint{margin-top:var(--space-md);padding:var(--space-sm) var(--space-md);background:var(--ochre-wash);border-radius:var(--radius-md);border-left:3px solid color-mix(in srgb,var(--ochre) 30%,transparent);font-size:var(--fs-body);color:var(--on-surface-dim);display:flex;align-items:flex-start;gap:var(--space-sm)}.hint-icon{flex-shrink:0}.steps-container{margin-top:var(--space-md)}.msg-footer{margin-top:var(--space-xl);display:flex;justify-content:flex-end}.logic-dropdown-minimal{font-size:var(--fs-caption);color:var(--on-surface-dim)}.logic-dropdown-minimal summary{list-style:none;cursor:pointer;padding:var(--space-xs) var(--space-sm);border-radius:var(--radius-sm);border:1px solid transparent;transition:all var(--transition-fast)}.logic-dropdown-minimal summary:hover{background:var(--surface-container-high);border-color:var(--outline-variant)}.logic-dropdown-minimal[open] summary{background:var(--surface-container-high);margin-bottom:var(--space-sm)}.chip-action.quick-q-btn:active{transform:scale(.98)}.chat-input-actions{display:flex;gap:var(--space-xs);padding-left:var(--space-xs)}.gemini-style{background:none!important;max-width:100%!important;padding:0!important}.gemini-style .msg-header{display:flex;align-items:center;gap:var(--space-md);margin-bottom:var(--space-md)}.ai-sparkle{color:var(--primary)}.logic-dropdown{background:var(--surface-container-low);border-radius:var(--radius-md);padding:0;font-size:var(--fs-caption);color:var(--on-surface-dim);border:1px solid var(--outline-variant);cursor:pointer;overflow:hidden;transition:all var(--transition-base)}.logic-dropdown:hover{border-color:var(--primary);background:var(--surface-container-high)}.logic-dropdown summary{list-style:none;font-family:var(--font-primary);padding:var(--space-xs) var(--space-md);display:flex;align-items:center;gap:var(--space-sm)}.logic-dropdown summary:before{content:"→";transition:transform var(--transition-base)}.logic-dropdown[open] summary:before{transform:rotate(90deg)}.logic-content{padding:var(--space-md);border-top:1px solid var(--outline-variant);line-height:1.6;border-left:2px solid var(--primary);margin:0;background:rgba(var(--primary-rgb),.02);color:var(--on-surface-dim);font-size:var(--fs-body-sm)}.logic-content strong{color:var(--on-surface-variant)}.msg-body{padding-left:34px}.msg-text{font-size:var(--fs-body);line-height:var(--lh-body);color:var(--on-surface);margin-bottom:var(--space-xl)}.msg-text strong,.step-txt strong{color:var(--primary);font-weight:600}.mono-inline{font-family:var(--font-primary);background:var(--surface-container-high);padding:.1em .3em;border-radius:var(--radius-sm);font-size:.9em;color:var(--secondary)}.katex-display{margin:1.5em 0!important;padding:1.25rem;background:var(--surface-container-lowest);border-radius:var(--radius-lg);border:1px solid var(--outline-variant);overflow-x:auto;overflow-y:hidden}.katex{font-size:1.25em!important;font-weight:500!important}.msg-steps-modern{display:grid;gap:var(--space-md);margin-bottom:var(--space-xl)}.step-card{display:flex;gap:var(--space-lg);background:var(--surface-container-lowest);padding:var(--space-lg);border-radius:var(--radius-lg);border:1px solid var(--outline-variant);transition:transform .2s ease}.step-card:hover{border-color:var(--primary)}.step-num{font-family:var(--font-primary);font-weight:700;color:var(--primary);opacity:.5;font-size:var(--fs-h3)}.step-txt{font-size:var(--fs-body);line-height:1.7}.formula-box{background:var(--surface-container-lowest);border:1px solid var(--outline-variant);padding:var(--space-2xl);border-radius:var(--radius-lg);margin:var(--space-xl) 0;text-align:center}.formula-label{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--on-surface-dim);margin-bottom:var(--space-md);font-weight:600}.formula-display{font-family:var(--font-primary);font-size:var(--fs-h3);color:var(--on-primary-container);text-align:center}.msg-question-prompt{display:flex;align-items:center;gap:var(--space-lg);background:var(--surface-container-low);padding:var(--space-lg) var(--space-xl);border-radius:var(--radius-lg);margin-top:var(--space-2xl);border:1px solid var(--outline-variant)}.prompt-icon{width:32px;height:32px;background:var(--marigold);color:var(--on-marigold);border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;font-weight:700}.prompt-text{font-size:var(--fs-body);color:var(--on-surface);font-weight:500}.history-overlay{position:absolute;top:0;left:0;right:0;bottom:0;background:#16223a66;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);z-index:1000;display:flex;align-items:flex-end;justify-content:center;padding-bottom:140px;opacity:0;pointer-events:none;transition:opacity .2s ease}.history-overlay.visible{opacity:1;pointer-events:all}.history-palette{width:90%;max-width:650px;background:var(--surface-container-lowest);border-radius:var(--radius-lg);box-shadow:var(--shadow-ambient);border:1px solid var(--outline-variant);overflow:hidden;transform:translateY(20px);transition:transform .3s cubic-bezier(.34,1.56,.64,1)}.history-overlay.visible .history-palette{transform:translateY(0)}.palette-header{padding:var(--space-md);border-bottom:1px solid var(--outline-variant)}.palette-search{width:100%;background:transparent;border:none;color:var(--on-surface);font-size:var(--fs-body);padding:var(--space-sm);outline:none}.palette-body{max-height:50vh;overflow-y:auto;padding:var(--space-sm)}.palette-group{margin-bottom:var(--space-md)}.palette-label{padding:var(--space-sm) var(--space-md);font-size:var(--fs-caption);font-weight:700;color:var(--primary)}.palette-item{display:flex;align-items:center;gap:var(--space-md);padding:var(--space-md);border-radius:var(--radius-md);cursor:pointer;transition:all .2s ease;color:var(--on-surface-variant)}.palette-item:hover{background:var(--surface-container-highest);color:var(--on-surface)}.palette-item.active{background:var(--marigold-wash);box-shadow:inset 3px 0 0 var(--marigold);color:var(--on-surface)}.item-icon{opacity:.5}.item-title{flex:1;min-width:0;font-size:var(--fs-body);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.item-meta{font-size:var(--fs-caption);opacity:.5;margin-right:var(--space-sm)}.delete-conv-btn{padding:var(--space-xs);border-radius:var(--radius-sm);color:var(--error);opacity:0;transition:opacity .2s ease;background:transparent;border:none;cursor:pointer}.palette-item:hover .delete-conv-btn{opacity:.6}.delete-conv-btn:hover{opacity:1!important;background:var(--not-quite-wash)}.palette-footer{padding:var(--space-sm) var(--space-md);background:var(--surface-container-low);border-top:1px solid var(--outline-variant)}.palette-hint{font-size:var(--fs-caption);color:var(--on-surface-dim);text-align:center;opacity:.6}.palette-empty{padding:var(--space-2xl);text-align:center;color:var(--on-surface-dim);font-style:italic;font-size:var(--fs-body-sm)}.calculator{background:var(--surface-container-lowest);border:1px solid var(--outline-variant);border-radius:var(--radius-lg);padding:var(--space-xl);max-width:360px}.calc-display{background:var(--surface-container-low);border-radius:var(--radius-lg);padding:var(--space-xl);margin-bottom:var(--space-lg);text-align:right;min-height:100px;display:flex;flex-direction:column;justify-content:flex-end}.calc-display .calc-previous{font-family:var(--font-primary);font-size:var(--fs-body-sm);color:var(--on-surface-dim);margin-bottom:var(--space-xs)}.calc-display .calc-current{font-family:var(--font-primary);font-size:var(--fs-h2);font-weight:500;color:var(--on-surface);word-break:break-all}.calc-display .calc-result{font-family:var(--font-primary);font-size:var(--fs-h3);color:var(--on-surface-variant);margin-top:var(--space-xs)}.calc-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-sm)}.calc-btn{height:52px;border:none;border-radius:var(--radius-md);font-family:var(--font-primary);font-size:var(--fs-body);font-weight:500;cursor:pointer;transition:all var(--transition-fast);display:flex;align-items:center;justify-content:center}.calc-btn.function{background:var(--surface-container-high);color:var(--on-surface-variant)}.calc-btn.number{background:var(--surface-container);color:var(--on-surface)}.calc-btn.operator{background:var(--primary-container);color:var(--primary)}.calc-btn.action{background:var(--secondary-container);color:var(--on-surface)}.calc-btn.equals{background:var(--primary);color:var(--on-primary);grid-column:span 1}.calc-btn:hover{filter:brightness(1.15)}.calc-btn:active{transform:translateY(0);filter:brightness(.95)}.quiz-card{background:var(--surface-container-lowest);border-radius:var(--radius-lg);padding:var(--space-3xl);max-width:600px}.quiz-header{margin-bottom:var(--space-2xl)}.quiz-chapter{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--primary);margin-bottom:var(--space-sm)}.quiz-title{font-family:var(--font-heading);font-size:var(--fs-h2);font-weight:700;color:var(--on-surface);line-height:1.3}.quiz-problem{background:var(--surface-container-lowest);border-radius:var(--radius-lg);padding:var(--space-2xl);margin-bottom:var(--space-2xl);position:relative}.quiz-problem .problem-label{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--on-surface-dim);margin-bottom:var(--space-lg)}.quiz-problem .problem-sigma{position:absolute;top:var(--space-lg);right:var(--space-xl);font-size:var(--fs-h1);color:var(--on-surface-dim);opacity:.3}.quiz-problem .problem-text{font-size:var(--fs-h3);line-height:1.6;color:var(--on-surface);margin-bottom:var(--space-lg)}.quiz-problem .problem-formula{background:var(--surface-container);border-radius:var(--radius-md);padding:var(--space-lg) var(--space-xl);font-family:var(--font-primary);font-size:var(--fs-h3);color:var(--on-surface);text-align:center}.quiz-meta{display:flex;align-items:center;gap:var(--space-lg);margin-bottom:var(--space-2xl)}.quiz-meta-item{display:flex;align-items:center;gap:var(--space-xs);font-family:var(--font-primary);font-size:var(--fs-caption)}.quiz-meta-item.hint{color:var(--tertiary);cursor:pointer}.quiz-meta-item.difficulty{color:var(--on-surface-dim)}.quiz-meta-item.xp{color:var(--primary)}.quiz-options-label{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--on-surface-dim);margin-bottom:var(--space-md)}.quiz-options{display:flex;flex-direction:column;gap:var(--space-sm)}.quiz-option{display:flex;align-items:center;justify-content:space-between;padding:var(--space-lg) var(--space-xl);background:var(--surface-container-lowest);border-radius:var(--radius-lg);cursor:pointer;transition:all var(--transition-fast);border:1px solid 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992px){.active-quiz-container{max-width:1100px!important}.quiz-card{max-width:100%!important;width:100%!important}.quiz-two-column-layout{display:grid!important;grid-template-columns:1.15fr .85fr!important;gap:1.5rem!important;align-items:start!important;padding:1.5rem!important;background:var(--surface-container-lowest)!important;box-shadow:none!important;border:1px solid var(--outline-variant)!important}.quiz-left-panel{display:flex!important;flex-direction:column!important;gap:.75rem!important;min-width:0}.quiz-right-panel{display:flex!important;flex-direction:column!important;gap:.75rem!important;background:var(--surface-container-low)!important;border:1px solid var(--outline-variant)!important;border-radius:var(--radius-lg)!important;padding:1.25rem!important}.quiz-problem{padding:1rem 1.25rem!important;border:1px solid var(--outline-variant)!important;box-shadow:none!important}.quiz-timer-widget{background:rgba(var(--primary-rgb),.12)!important;border:1px solid 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768px){.app-layout{display:flex;flex-direction:column;margin-left:0!important;padding-left:0!important}.main-content{margin-left:0!important;padding-left:0!important;height:100dvh!important;padding-bottom:calc(64px + env(safe-area-inset-bottom,0px))!important;display:flex;flex-direction:column}.bottom-nav{position:fixed;bottom:0;left:0;right:0;height:calc(60px + env(safe-area-inset-bottom,0px));padding-bottom:env(safe-area-inset-bottom,0px);background:var(--surface-container-lowest);border-top:1px solid var(--outline-variant);display:flex!important;justify-content:space-around;align-items:center;z-index:999;transform:none;width:auto;max-width:none;border-radius:0;box-shadow:none;padding-left:0;padding-right:0}.chat-container{display:flex;flex-direction:column;height:calc(100dvh - 60px)!important;min-height:0;position:relative;overflow:hidden}.chat-messages{flex:1;min-height:0;overflow-y:auto;padding-bottom:2rem!important}.premium-chat 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var(--primary))}.calc-dropdown-chevron{color:var(--ink-2);transition:transform .2s cubic-bezier(.4,0,.2,1)}.calc-dropdown-trigger.active .calc-dropdown-chevron{transform:rotate(180deg);color:var(--primary, var(--ink))}.calc-dropdown-menu{position:absolute;top:calc(100% + 6px);left:0;width:100%;background:var(--surface-container-lowest);border:1px solid var(--outline-variant);border-radius:12px;padding:6px;list-style:none;display:none;flex-direction:column;gap:4px;z-index:100;box-shadow:var(--shadow-ambient);animation:calcDropdownIn .2s cubic-bezier(.16,1,.3,1)}.calc-dropdown-menu.open{display:flex}@keyframes calcDropdownIn{0%{opacity:0;transform:translateY(-8px) scale(.98)}to{opacity:1;transform:translateY(0) scale(1)}}.calc-dropdown-item{padding:10px 14px;border-radius:8px;font-size:var(--fs-caption);font-weight:500;color:var(--ink-2);cursor:pointer;transition:all .15s 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.calc-btn:hover{background:rgba(var(--primary-rgb),.08)!important;border-color:var(--primary)!important;color:var(--on-surface)!important}#main-content{min-height:0!important;overflow-y:auto}.main-content.chat-mode-active #main-content{overflow-y:hidden!important}.dropdown-item{transition:background var(--transition-fast),color var(--transition-fast);outline:none}.dropdown-item:hover,.dropdown-item:focus{background:var(--surface-container-high)!important;color:var(--primary)!important}.dropdown-item#top-logout-btn:hover,.dropdown-item#top-logout-btn:focus{background:var(--error-container)!important;color:var(--error)!important}.chapter-view-container{height:100%;min-height:0;display:flex;flex-direction:column}.chapter-view-container>.page-header{display:flex!important;margin-bottom:0!important;padding:8px 16px!important;min-height:48px!important;background:var(--surface-container-low);border-bottom:1px solid var(--outline-variant);border-top-left-radius:16px;border-top-right-radius:16px;align-items:center;justify-content:space-between}.chapter-view-container>.page-header .headline-lg{font-size:var(--fs-body)!important;font-weight:700!important;margin:0!important}.chapter-view-container>.page-header .page-header-left{gap:var(--space-md)!important}.chapter-view-container>.page-header .status-bar{display:none!important}.chapter-view-container>.page-header .pill-tabs-wrapper{margin-top:0!important}.chapter-view-container .chapter-content-area{display:flex;flex-direction:column;flex:1;min-height:0;height:100%!important;box-sizing:border-box}.chapter-view-container .tab-container{min-height:0;height:100%!important;box-sizing:border-box}.chapter-view-container #study-tab-container,.chapter-view-container #constructions-tab-container,.chapter-view-container #cases-tab-container,.chapter-view-container #loader-tab-container{overflow-y:auto;padding:1.5rem 0}.chapter-view-container #chat-tab-container{display:flex;flex-direction:column;flex:1;overflow:hidden!important}.main-content.chat-mode-active{padding:0!important;overflow:hidden}.chatbot-page{position:relative;width:100%;max-width:100%;margin:0 auto;background:var(--surface);border-left:1px solid var(--outline-variant);border-right:1px solid var(--outline-variant);display:flex;flex-direction:column;flex:1;min-height:0;height:100%}.chatbot-page .chat-messages{width:100%;max-width:100%!important;margin:0 auto;padding:.75rem 1.25rem!important;gap:.75rem!important}.chatbot-page .chat-msg{padding:8px 12px!important;margin-bottom:.5rem!important;max-width:80%!important}.chatbot-page .chat-msg .msg-body{padding:8px 12px!important;border-radius:12px!important}.chatbot-page .chat-welcome-area{padding:1rem 1rem .5rem!important;display:flex;flex-direction:column;align-items:center;text-align:center}.chatbot-page .welcome-label{font-size:var(--fs-caption)!important}.chatbot-page .welcome-headline{margin-top:.25rem!important;margin-bottom:.75rem!important;font-size:var(--fs-h3)!important}.chatbot-page .quick-questions{margin-top:.25rem!important;margin-bottom:.75rem!important;display:flex;flex-wrap:wrap;justify-content:center;gap:.4rem}.chatbot-page .quick-q-btn{padding:6px 12px!important;font-size:var(--fs-caption)!important}.chatbot-page .welcome-subtext{max-width:500px;margin:.75rem auto 0!important;font-size:var(--fs-caption)!important;line-height:1.4!important}.chatbot-page .chat-toolbar{position:relative!important;bottom:auto!important;z-index:20;padding:.5rem 1rem!important;background:var(--surface-container-low)}.chatbot-page .chat-toolbar-inner{max-width:100%!important}.chatbot-page .chat-input-bar{min-height:64px!important;border-radius:20px!important;padding:10px 14px!important;border:1px solid var(--outline)!important;background:var(--surface-container-lowest)!important;transition:border-color .2s,box-shadow 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rgba(var(--primary-rgb),.15)!important;color:var(--primary)!important;font-size:var(--fs-caption)!important;font-weight:600!important;cursor:pointer;font-family:var(--font-primary)!important;transition:all .2s}.chatbot-page .mode-select-pill:hover{background:rgba(var(--primary-rgb),.15)!important;border-color:rgba(var(--primary-rgb),.3)!important}.chatbot-page .mode-dropdown-menu{background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:12px!important;box-shadow:var(--shadow-ambient)!important;min-width:220px;z-index:1000;flex-direction:column;padding:6px!important;gap:2px!important}.chatbot-page .mode-dropdown-item{text-align:left;padding:8px 12px!important;background:none!important;border:none!important;border-radius:8px!important;color:var(--on-surface)!important;font-size:var(--fs-caption)!important;cursor:pointer;display:flex;flex-direction:column;gap:2px;transition:background .2s;width:100%}.chatbot-page .mode-dropdown-item:hover{background:rgba(var(--primary-rgb),.05)!important}.chatbot-page .mode-dropdown-item.active{background:var(--marigold-wash)!important;color:var(--on-surface)!important}.chatbot-page .symbols-popover{background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:12px!important;box-shadow:var(--shadow-ambient)!important;width:280px;z-index:1000;padding:12px!important}.chatbot-page .symbols-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:6px!important}.chatbot-page .symbols-grid .math-helper-btn{padding:6px!important;font-size:var(--fs-caption)!important;border-radius:6px!important;background:var(--surface-container-low)!important;border:1px solid var(--outline-variant)!important;color:var(--on-surface)!important;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:background .2s,border-color .2s}.chatbot-page .symbols-grid .math-helper-btn:hover{background:rgba(var(--primary-rgb),.1)!important;border-color:var(--primary)!important;color:var(--primary)!important}.history-drawer{display:flex;width:380px!important;flex-shrink:0;border-left:1px solid var(--outline-variant);background:var(--surface-container-low);flex-direction:column;transition:all .3s ease;height:100%}@media (max-width: 768px){.history-drawer{position:absolute!important;top:0;right:0;width:100%!important;height:100%;z-index:50;border-left:none;box-shadow:var(--shadow-ambient)}}.chatbot-page .calc-modal-mount{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;z-index:30;overflow:hidden;pointer-events:none}.chatbot-page .calc-overlay{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;background:transparent;pointer-events:none;display:flex;align-items:flex-start;justify-content:flex-end;padding:1.5rem;box-sizing:border-box}.chatbot-page .calc-modal{width:270px!important;background:var(--surface-container-lowest);border:1px solid var(--outline-variant);border-radius:16px!important;padding:.75rem!important;box-shadow:var(--shadow-ambient);pointer-events:auto;-webkit-user-select:none;user-select:none;touch-action:none;z-index:41}.chatbot-page .calc-header{margin-bottom:.75rem!important}.chatbot-page .calc-brand{font-size:var(--fs-body-sm)!important}.chatbot-page .calc-display{padding:.75rem!important;margin-bottom:.75rem!important;min-height:70px!important}.chatbot-page .calc-expression{font-size:var(--fs-body)!important}.chatbot-page .calc-result{font-size:var(--fs-h2)!important}.chatbot-page .calc-grid,.chatbot-page .calc-row-main{gap:.4rem!important}.chatbot-page .calc-btn{height:36px!important;border-radius:8px!important;font-size:var(--fs-caption)!important}.chatbot-page .calc-dropdown-container{margin-bottom:.4rem!important}.chatbot-page .calc-dropdown-trigger{padding:6px 10px!important;font-size:var(--fs-caption)!important}.chatbot-page .calc-functions-panel .calc-btn{font-size:var(--fs-caption)!important}.chatbot-page .scroll-bottom-btn{position:absolute;right:1.5rem;bottom:7rem}@media (max-width: 900px){.chatbot-page{border-left:0;border-right:0}.chatbot-page .chat-messages{padding:.5rem .75rem 1rem!important}.chatbot-page .chat-toolbar{padding:.5rem .75rem .75rem!important}}@media (max-width: 768px){.chatbot-page .chat-input-bar{min-height:56px!important;padding:8px 12px!important;border-radius:20px!important}.chatbot-page .calc-overlay{position:fixed!important;top:0;left:0;width:100vw!important;height:100vh!important;background:#16223a66!important;pointer-events:auto!important;display:flex!important;align-items:flex-end!important;justify-content:center!important;padding:0!important;z-index:1000!important}.chatbot-page .calc-modal{width:100%!important;max-width:500px!important;border-radius:24px 24px 0 0!important;border-bottom:none!important;padding:1.25rem 1.25rem 2rem!important;margin-bottom:0!important;transform:none!important;box-shadow:var(--shadow-ambient)!important}}.quiz-spinner{display:inline-block;width:14px;height:14px;border:2px solid var(--outline);border-radius:50%;border-top-color:var(--on-surface);animation:quiz-spin .6s linear infinite;margin-right:8px;vertical-align:middle}@keyframes quiz-spin{to{transform:rotate(360deg)}}#route-loading-progress{position:fixed;top:0;left:0;width:0%;height:3px;background:var(--primary);z-index:99999;transition:width .4s ease,opacity .3s ease;pointer-events:none;opacity:0}.skeleton-pulse{background:var(--surface-container);animation:skeletonPulse 1.5s ease-in-out infinite;border-radius:6px}.timeline-container{position:relative;max-width:700px;margin-top:1.5rem;margin-bottom:2rem}.timeline-line{position:absolute;left:20px;top:8px;bottom:8px;width:2px;background:rgba(var(--primary-rgb),.1);z-index:1}.timeline-group{margin-bottom:2rem;position:relative;z-index:2}.timeline-group-header{font-family:var(--font-primary);font-size:var(--fs-caption);font-weight:600;color:var(--primary);margin-bottom:1rem;background:var(--surface);display:inline-block;padding-right:1rem}.timeline-item{display:flex;gap:1.5rem;margin-bottom:1.25rem;position:relative}.timeline-node{width:40px;height:40px;border-radius:50%;background:var(--surface-container-lowest);border:2px solid var(--outline-variant);display:flex;align-items:center;justify-content:center;flex-shrink:0;z-index:2;color:var(--on-surface-variant);transition:all .2s ease}.timeline-item:hover .timeline-node{border-color:var(--primary);color:var(--primary)}.timeline-node svg{width:18px;height:18px;stroke-width:2.25}.timeline-card-wrapper{flex:1;min-width:0;text-decoration:none;display:block}.timeline-card{background:var(--surface-container-lowest);border:1px solid var(--outline-variant);border-radius:var(--radius-lg);padding:1.25rem;transition:all .2s cubic-bezier(.4,0,.2,1);cursor:pointer}.timeline-card-wrapper:hover .timeline-card{border-color:var(--outline);background:var(--surface-container-low)}.timeline-card-header{display:flex;justify-content:space-between;align-items:flex-start;gap:.5rem;margin-bottom:.5rem}.timeline-card-title{font-size:var(--fs-body);font-weight:600;color:var(--on-surface)}.timeline-card-meta{font-family:var(--font-primary);font-size:var(--fs-caption);color:var(--on-surface-dim)}.timeline-card-details{display:flex;flex-wrap:wrap;gap:1rem;margin-top:.5rem;padding-top:.5rem;border-top:1px solid var(--outline-variant)}.timeline-detail-item{display:flex;align-items:center;gap:.25rem;font-size:var(--fs-caption);color:var(--on-surface-variant)}.timeline-detail-item strong{color:var(--on-surface)}.timeline-badge{font-family:var(--font-primary);font-size:var(--fs-caption);font-weight:700;padding:.2rem .5rem;border-radius:4px}.timeline-badge.quiz_completed{background:var(--correct-wash);color:var(--correct)}.timeline-badge.quiz_attempted{background:var(--ochre-wash);color:var(--ochre)}.timeline-badge.chat_started{background:rgba(var(--primary-rgb),.1);color:var(--primary)}.timeline-badge.chat_resumed{background:rgba(var(--primary-rgb),.1);color:var(--ink)}.load-more-container{display:flex;justify-content:center;margin-top:2rem;max-width:700px;padding-bottom:4rem}.btn-load-more{background:var(--surface-container-lowest);color:var(--on-surface);border:1px solid var(--outline-variant);padding:.75rem 2rem;border-radius:var(--radius-full);font-family:inherit;font-size:var(--fs-label);font-weight:500;cursor:pointer;transition:all .2s;display:flex;align-items:center;gap:.5rem}.btn-load-more:hover{background:var(--surface-container-low);border-color:var(--primary)}.btn-load-more:disabled{opacity:.5;cursor:not-allowed}.btn-spinner{display:inline-block;width:14px;height:14px;border:2px solid var(--outline-variant);border-radius:50%;border-top-color:var(--on-surface);animation:btn-spin .6s linear infinite}@keyframes btn-spin{to{transform:rotate(360deg)}}@media (max-width: 768px){.timeline-item{gap:1rem}.timeline-node{width:32px;height:32px;border-width:1.5px}.timeline-node svg{width:14px;height:14px}.timeline-line{left:16px}}.chat-input-accessory-bar{display:flex;align-items:center;justify-content:space-between;width:100%;padding:4px 8px;background:transparent;box-sizing:border-box}.chat-input-accessory-bar .btn-icon-pill{width:36px;height:36px;border-radius:50%;border:none;background:transparent;color:var(--on-surface-variant);opacity:.75;transition:all .2s ease;display:flex;align-items:center;justify-content:center;cursor:pointer}.chat-input-accessory-bar .btn-icon-pill:hover{background:rgba(var(--primary-rgb),.06);opacity:1;color:var(--primary)}.chat-input-accessory-bar .btn-icon-pill.active{background:rgba(var(--primary-rgb),.1);opacity:1;color:var(--primary)}.chat-input-accessory-bar .mode-select-pill{display:flex;align-items:center;gap:4px;padding:6px 12px;border-radius:12px;background:rgba(var(--primary-rgb),.08);border:1px solid rgba(var(--primary-rgb),.18);color:var(--primary);font-size:var(--fs-caption);font-weight:600;cursor:pointer;font-family:var(--font-primary);transition:all .2s ease}.chat-input-accessory-bar .mode-select-pill:hover{background:rgba(var(--primary-rgb),.15);border-color:rgba(var(--primary-rgb),.3)}.history-drawer{display:flex!important;width:0px!important;opacity:0;overflow:hidden;flex-shrink:0;border-left:none;background:var(--surface-container-low);flex-direction:column;transition:width .3s cubic-bezier(.4,0,.2,1),opacity .3s ease;height:100%}.history-drawer.open{width:380px!important;opacity:1;border-left:1px solid var(--outline-variant)}body:has(.chapter-chat-active) .bottom-nav{display:none!important}body:has(.chapter-chat-active) .chat-container{height:100dvh!important}@media (max-width: 768px){.chapter-chat-active .premium-header{padding:6px 12px!important;min-height:44px!important}.chapter-chat-active .back-link span{display:none!important}.chapter-chat-active .headline-lg{font-size:var(--fs-body)!important;white-space:nowrap;text-overflow:ellipsis;overflow:hidden;max-width:140px}.chapter-chat-active .pill-tabs-wrapper{margin-top:4px!important}.chapter-chat-active .pill-tab{padding:4px 8px!important;font-size:var(--fs-caption)!important}.history-drawer{position:absolute!important;top:0;right:0;width:100%!important;height:100%;transform:translate(100%);opacity:1!important;z-index:5000!important;border-left:none;box-shadow:var(--shadow-ambient);transition:transform .3s cubic-bezier(.4,0,.2,1)!important}.history-drawer.open{transform:translate(0)!important}.chatbot-page .calc-drag-handle-container{display:flex!important}.chatbot-page .calc-modal{width:100%!important;max-width:500px!important;border-radius:20px 20px 0 0!important;padding:8px 12px 24px!important;background:var(--surface-container-lowest)!important}.premium-chat .chat-toolbar{padding:6px 10px calc(6px + env(safe-area-inset-bottom,0px)) 10px!important}.chat-input-bar{min-height:42px!important;padding:6px 8px 6px 12px!important;border-radius:20px!important}}@media (min-width: 769px){.app-header{display:flex!important;position:sticky!important;top:0!important;width:100%!important;height:64px!important;background:var(--surface)!important;border-bottom:1px solid var(--outline-variant)!important;z-index:1500!important;pointer-events:auto!important;padding-right:var(--space-xl)!important}.app-header #sidebar-burger,.app-header .logo-container{display:none!important}.app-header .header-actions{pointer-events:auto!important}.premium-header{height:64px!important;padding:0 var(--space-xl)!important;display:flex!important;align-items:center!important;justify-content:space-between!important;box-sizing:border-box!important}.premium-header .header-content{flex:1!important;display:flex!important;align-items:center!important;justify-content:space-between!important;flex-wrap:nowrap!important;gap:1.5rem!important}.premium-header .pill-tabs-wrapper{margin-top:0!important}}@media (max-width: 768px){body:has(#main-content.chapter-view-active) .app-header{display:none!important}.chapter-view-container{padding-top:0!important}.chapter-view-container .premium-header{min-height:52px!important;padding:8px 12px!important;display:flex!important;flex-direction:column!important;justify-content:center!important;box-sizing:border-box!important}.chapter-view-container .premium-header .header-content{display:flex!important;align-items:center!important;justify-content:space-between!important;width:100%!important;gap:8px!important}.premium-header .pill-tabs-wrapper{overflow-x:auto!important;scrollbar-width:none!important;-ms-overflow-style:none!important;width:100%!important;margin-top:6px!important}.premium-header .pill-tabs-wrapper::-webkit-scrollbar{display:none!important}.premium-header .pill-tabs{display:flex!important;flex-wrap:nowrap!important;gap:6px!important;width:max-content!important;padding-bottom:2px!important}.premium-header .pill-tab{padding:4px 10px!important;font-size:var(--fs-caption)!important;white-space:nowrap!important}}@media (min-width: 769px){.chat-body{max-width:900px!important;margin:0 auto!important;width:100%!important;box-sizing:border-box!important}.chat-toolbar-inner{max-width:800px!important;margin:0 auto!important;padding:.75rem 0!important}.chat-toolbar{background:transparent!important;border-top:none!important}.chat-input-container{background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:24px!important;padding:10px 16px!important;box-shadow:none!important}}@media (max-width: 768px){.premium-chat .chat-toolbar{position:fixed!important;bottom:0!important;left:0!important;right:0!important;width:100%!important;background:var(--surface)!important;border-top:1px solid var(--outline-variant)!important;padding:8px 12px calc(8px + env(safe-area-inset-bottom,0px)) 12px!important;z-index:1000!important;box-sizing:border-box!important;transition:transform .1s ease-out!important}.premium-chat .chat-messages{padding-bottom:140px!important}}.chat-welcome-area{display:flex!important;flex-direction:column!important;align-items:center!important;justify-content:center!important;max-width:600px!important;margin:3rem auto auto!important;padding:2.5rem 2rem!important;background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:var(--radius-lg)!important;text-align:center!important}.chatbot-page .quick-questions{display:flex!important;flex-direction:column!important;gap:10px!important;width:100%!important;margin-top:1.5rem!important;margin-bottom:1.5rem!important}.chatbot-page .quick-q-btn{width:100%!important;padding:12px 16px!important;font-size:var(--fs-label)!important;font-weight:500!important;background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:var(--radius-md)!important;color:var(--on-surface)!important;text-align:left!important;display:flex!important;align-items:center!important;gap:10px!important;cursor:pointer!important;transition:all .25s cubic-bezier(.4,0,.2,1)!important}.chatbot-page .quick-q-btn:hover{background:var(--surface-container-low)!important;border-color:var(--outline)!important}@media (max-width: 768px){.chat-input-accessory-bar{display:flex!important;align-items:center!important;gap:6px!important;padding:4px 0!important;overflow-x:auto!important;scrollbar-width:none!important;width:100%!important}.chat-input-accessory-bar::-webkit-scrollbar{display:none!important}.chat-input-accessory-bar .btn-icon-pill,.chat-input-accessory-bar label.btn-icon-pill{width:38px!important;height:38px!important;flex-shrink:0!important}.chat-input-accessory-bar .mode-select-pill{flex-shrink:0!important;height:36px!important;display:flex!important;align-items:center!important}}@media (max-width: 768px){.chatbot-page .symbols-popover{position:absolute!important;bottom:100%!important;left:16px!important;right:16px!important;width:auto!important;border-radius:12px!important;border:1px solid var(--outline-variant)!important;background:var(--surface-container-lowest)!important;padding:12px!important;z-index:2000!important;transform:none!important;transition:none!important;box-shadow:var(--shadow-ambient)!important;box-sizing:border-box!important;margin-bottom:8px!important}}.chat-math-preview-wrapper{position:absolute!important;bottom:calc(100% + 12px)!important;left:0!important;right:0!important;background:var(--surface-container-lowest)!important;border:1px solid var(--outline-variant)!important;border-radius:16px!important;padding:12px 16px!important;box-shadow:var(--shadow-ambient)!important;z-index:105!important;box-sizing:border-box!important;animation:floatFadeIn .2s cubic-bezier(.4,0,.2,1)!important}.chat-math-preview{color:var(--primary)!important;font-size:var(--fs-body)!important;overflow-x:auto!important;text-align:left!important;scrollbar-width:thin!important}@keyframes floatFadeIn{0%{opacity:0;transform:translateY(6px) scale(.98)}to{opacity:1;transform:translateY(0) scale(1)}}@media (max-width: 768px){.history-drawer{position:fixed!important;top:0!important;left:0!important;right:0!important;width:100%!important;height:100dvh!important;transform:translate(100%)!important;z-index:5000!important;background:var(--surface-container-low)!important;box-sizing:border-box!important;box-shadow:none!important;transition:transform .3s cubic-bezier(.4,0,.2,1)!important}.history-drawer.open{transform:translate(0)!important}}.sidebar-footer{margin-top:auto!important;border-top:1px solid var(--outline-variant)!important;padding:12px!important;transition:all .3s ease!important}@media (min-width: 769px){.sidebar.collapsed .sidebar-footer{padding:12px 0!important;border-top:none!important}.sidebar.collapsed .profile-text{display:none!important}.sidebar.collapsed .sidebar-profile-btn{justify-content:center!important;padding:8px 0!important}}.sidebar-profile-btn:hover{background:rgba(var(--primary-rgb),.04)!important}@media (max-width: 768px){.chatbot-page .mode-dropdown-menu{position:fixed!important;bottom:calc(72px + env(safe-area-inset-bottom,0px))!important;left:12px!important;right:12px!important;width:auto!important;min-width:0!important;z-index:3000!important;margin-bottom:0!important;box-shadow:var(--shadow-ambient)!important}body:has(.calc-overlay) .chat-toolbar{display:none!important}.chatbot-page .calc-overlay{position:fixed!important;top:0!important;left:0!important;right:0!important;bottom:0!important;height:auto!important;width:100%!important;z-index:2500!important}.premium-chat .chat-toolbar{transition:transform .3s cubic-bezier(.4,0,.2,1)!important}.chat-input-bar textarea::placeholder{white-space:nowrap!important;overflow:hidden!important;text-overflow:ellipsis!important}.chat-input-bar textarea::-webkit-input-placeholder{white-space:nowrap!important;overflow:hidden!important;text-overflow:ellipsis!important}}@media (min-width: 769px){.chapter-view-container .premium-header{display:none!important}.app-header.workspace-active{position:sticky!important;top:0!important;left:0!important;width:100%!important;height:64px!important;background:var(--surface)!important;border-bottom:1px solid var(--outline-variant)!important;z-index:2000!important;pointer-events:auto!important;padding:0 var(--space-xl)!important;display:flex!important;align-items:center!important;justify-content:space-between!important}.app-header.workspace-active #sidebar-burger,.app-header.workspace-active .logo-container{display:none!important}.app-header.workspace-active #app-header-workspace-left{display:flex!important;align-items:center;gap:12px}.app-header.workspace-active #app-header-workspace-center{display:flex!important;align-items:center;justify-content:center;flex:1}}@media (min-width: 769px){.chat-main-layout{overflow-y:auto!important}.chat-body{max-width:900px!important;margin:0 auto!important;width:100%!important;overflow:visible!important;height:auto!important}.chat-messages{max-width:100%!important;width:100%!important;overflow:visible!important;height:auto!important}.chat-toolbar{position:sticky!important;bottom:0!important;z-index:20!important}.history-drawer{position:sticky!important;top:0!important;height:calc(100vh - 64px)!important}}.math-symbols-ribbon{display:none!important;gap:8px!important;overflow-x:auto!important;scrollbar-width:none!important;padding:6px 0!important;margin-bottom:2px!important;width:100%!important;border-bottom:1px solid 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var(--ruling-strong);border-radius:var(--radius-full);background:var(--sheet);color:var(--ink);font-family:var(--font-primary);font-size:var(--fs-caption);font-weight:600;font-variant-numeric:tabular-nums;cursor:pointer;white-space:nowrap}.bl-pill:hover{background:var(--surface-container-low)}.bl-pill.is-low{border-color:var(--ochre);color:var(--ochre)}.bl-pill.is-empty{border-color:var(--not-quite);color:var(--not-quite)}.bl-page{max-width:760px;margin:0 auto;padding:var(--space-2xl) var(--space-lg) var(--space-4xl)}.bl-page h1{font-family:var(--font-heading);font-size:var(--fs-h1);line-height:var(--lh-h1);font-stretch:87.5%;margin:0 0 var(--space-xs)}.bl-page h2{font-family:var(--font-heading);font-size:var(--fs-h3);line-height:var(--lh-h3);margin:var(--space-2xl) 0 var(--space-md)}.bl-card{background:var(--sheet);border:1px solid var(--ruling);border-radius:var(--radius-lg);padding:var(--space-xl)}.bl-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:var(--space-lg);margin-bottom:var(--space-lg)}.bl-stat-label{font-size:var(--fs-caption);color:var(--ink-3)}.bl-stat-value{font-size:var(--fs-h2);line-height:var(--lh-h2);font-weight:700;font-variant-numeric:tabular-nums}.bl-actions{display:flex;flex-wrap:wrap;gap:var(--space-md)}.bl-table{width:100%;border-collapse:collapse;font-size:var(--fs-body-sm);font-variant-numeric:tabular-nums}.bl-table th{text-align:left;font-weight:500;font-size:var(--fs-caption);color:var(--ink-3);padding:var(--space-sm) var(--space-md);border-bottom:1px solid var(--ruling-strong)}.bl-table td{padding:var(--space-md);border-bottom:1px solid var(--ruling)}.bl-link{background:none;border:none;padding:0;color:var(--ink);text-decoration:underline;font:inherit;cursor:pointer}.bl-receipt dl{display:grid;grid-template-columns:max-content 1fr;gap:var(--space-sm) var(--space-lg);margin:var(--space-lg) 0;font-size:var(--fs-body-sm)}.bl-receipt dt{color:var(--ink-3)}.bl-receipt dd{margin:0;font-variant-numeric:tabular-nums}@media (max-width: 520px){.bl-packs{grid-template-columns:1fr}.bl-table th:nth-child(3),.bl-table td:nth-child(3){display:none}}@media print{body>*:not(#mathemate-dialogs-root){display:none!important}.bl-overlay{position:static;background:none;padding:0}.bl-modal{box-shadow:none;border:none;max-height:none}.bl-close,.bl-no-print{display:none!important}}