:root{--bg-color: #F9FAFC;--container-bg: #FFFFFF;--text-color: #212529;--display-bg: #F1F3F5;--display-border: #E9ECEF;--btn-bg: #FFFFFF;--btn-text: #212529;--btn-shadow: rgba(0, 0, 0, .05);--btn-action-bg: #E7F5FF;--btn-action-text: #1864AB;--accent-bg: #FF6B6B;--accent-text: #FFFFFF;--operator-bg: #FFF3BF;--operator-text: #D9480F;--sci-bg: #F3F0FF;--sci-text: #5F3DC4;--clear-bg: #FF6B6B;--clear-text: #FFFFFF;--shadow-color: rgba(0, 0, 0, .1)}.dark-mode{--bg-color: #121212;--container-bg: #1E1E1E;--text-color: #E0E0E0;--display-bg: #2D2D2D;--display-border: #404040;--btn-bg: #2D2D2D;--btn-text: #E0E0E0;--btn-shadow: rgba(0, 0, 0, .2);--btn-action-bg: #333A45;--btn-action-text: #74C0FC;--accent-bg: #FA5252;--accent-text: #FFFFFF;--operator-bg: #453A2D;--operator-text: #FFD43B;--sci-bg: #3A3045;--sci-text: #B197FC;--clear-bg: #FA5252;--clear-text: #FFFFFF;--shadow-color: rgba(0, 0, 0, .4)}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;background:var(--bg-color);color:var(--text-color);display:flex;justify-content:center;align-items:center;height:100vh;margin:0;transition:background .3s ease,color .3s ease;overflow-x:hidden}.container{background:var(--container-bg);padding:20px;width:360px;border-radius:14px;box-shadow:0 10px 30px var(--shadow-color);transition:background .3s ease,box-shadow .3s ease,width .3s ease;backdrop-filter:blur(15px);-webkit-backdrop-filter:blur(15px);border:1px solid var(--display-border);position:relative;overflow:hidden}body.dark-mode .container{background:#00000040;border:1px solid rgba(255,255,255,.1)}.container.scientific-mode,.container.graphing-mode{width:750px}.header{display:flex;justify-content:space-between;align-items:center;margin-bottom:6px;flex-wrap:nowrap}.header-left{display:flex;align-items:center;gap:10px;flex:1;min-width:0}h2{margin:0;font-weight:700;font-size:1.2rem;color:var(--text-color);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.toggles{display:flex;gap:10px;align-items:center;flex-shrink:0}.theme-switch{display:inline-flex;align-items:center;cursor:pointer}.theme-switch input{opacity:0;width:0;height:0}.slider{position:relative;width:2.5rem;height:1.4rem;background-color:#e8e8e8;border:2px solid var(--text-color);border-radius:1.5rem;transition:.4s}.slider:before{content:"🌙";position:absolute;width:1.1rem;height:1.1rem;left:2px;top:1px;background-color:var(--text-color);color:var(--bg-color);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:.75rem;transition:.4s}.mode-slider{background-color:var(--btn-action-bg)}.mode-slider:before{display:none}.toggle-text{position:absolute;width:100%;text-align:center;font-size:.7rem;font-weight:700;color:#fff;pointer-events:none;line-height:1.4rem}input:checked+.slider{background-color:#333;border-color:var(--text-color)}input:checked+.slider:before{transform:translate(1.1rem);content:"☀️"}input:not(:checked)+.mode-slider .toggle-text:after{content:"Std"}input:checked+.mode-slider .toggle-text:after{content:"Sci"}#display{width:100%;padding:15px 25px 15px 15px;font-size:24px;text-align:right;margin-bottom:10px;border-radius:8px;border:1px solid var(--display-border);box-sizing:border-box;background:var(--display-bg);color:var(--text-color)}#display[readonly]{font-weight:600}#display::placeholder{font-size:22px;color:#999}.voice-btn-container{display:flex;gap:10px;margin-bottom:15px}.voice-btn{flex:1;padding:12px;background:var(--accent-bg);color:var(--accent-text);font-size:18px;border:none;border-radius:8px;cursor:pointer;transition:transform .1s}.voice-btn:active{transform:scale(.95)}.sidebar{position:absolute;top:0;left:-280px;width:280px;height:100%;background:var(--bg-color);box-shadow:2px 0 10px #0003;z-index:2000;transition:left .3s ease;display:flex;flex-direction:column;padding:20px;box-sizing:border-box}.sidebar.open{left:0}.sidebar-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:30px;border-bottom:1px solid var(--display-border);padding-bottom:10px}.sidebar-header h3{margin:0;color:var(--text-color)}.sidebar-content{flex:1;overflow-y:auto;-ms-overflow-style:none;scrollbar-width:none}.sidebar-content::-webkit-scrollbar{display:none}.menu-item{background:none;border:none;width:100%;text-align:left;padding:15px;font-size:1.1rem;color:var(--text-color);cursor:pointer;border-radius:8px;transition:background .2s}.menu-item:hover{background:var(--btn-action-bg);color:var(--btn-action-text)}.overlay{position:absolute;top:0;left:0;width:100%;height:100%;background:#00000080;z-index:1500;display:none;opacity:0;transition:opacity .3s}.overlay.visible{display:block;opacity:1}.icon-btn{background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text-color);padding:5px;border-radius:50%;transition:background .3s;display:flex;align-items:center;justify-content:center}.icon-btn:hover{background:#0000001a}.keys-container{display:flex;gap:20px;margin-top:6px;justify-content:center}.std-keys{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;flex:1}.sci-keys{display:none;grid-template-columns:repeat(3,1fr);gap:10px;flex:.8}.sci-keys.visible{display:grid}.btn{padding:14px;background:var(--btn-bg);color:var(--btn-text);border:1px solid transparent;font-size:18px;border-radius:10px;cursor:pointer;transition:transform .08s ease,box-shadow .08s ease,background .3s}.btn:hover{transform:translateY(-3px);box-shadow:0 6px 16px #0000001a}.btn.pressed{transform:scale(.95) translateY(0);box-shadow:none}.btn[data-action]{background:var(--btn-action-bg);color:var(--btn-action-text)}.btn.sci{background:var(--sci-bg);color:var(--sci-text);font-size:15px;font-weight:600}.operator{background:var(--operator-bg);color:var(--operator-text)}.equal{background:var(--accent-bg);color:var(--accent-text)}.clear{background:var(--clear-bg);color:var(--clear-text)}#ceBtn{background:var(--btn-action-bg);color:var(--btn-action-text);font-weight:700}.btn.hidden{display:none}#status{text-align:center;margin-top:10px;font-size:13px;color:var(--text-color);opacity:.8}@media(max-width:850px){body{padding:10px;align-items:flex-start;height:auto;min-height:100vh}.container{width:100%;max-width:400px;padding:16px;margin:20px 0}.container.scientific-mode{width:100%;max-width:400px}.keys-container{flex-direction:column-reverse;gap:15px}.sci-keys{display:none;grid-template-columns:repeat(4,1fr);flex:none;width:100%}.sci-keys.visible{display:grid}.std-keys{width:100%;flex:none}.btn{padding:15px;font-size:18px}.btn.sci{font-size:14px;padding:12px}}@media(max-width:480px){.btn{padding:12px;font-size:16px}}#bg-container{position:fixed;top:0;left:0;width:100%;height:100%;z-index:-1;overflow:hidden;background:linear-gradient(120deg,#e0c3fc,#8ec5fc)}body.dark-mode #bg-container{background:linear-gradient(to top,#09203f,#537895)}#bg-container video,#bg-container img{width:100%;height:100%;object-fit:cover}#changeBgBtn{position:static;display:block;width:100%;padding:15px 20px;background:transparent;color:var(--text-color);border:none;border-radius:0;cursor:pointer;text-align:left;font-size:16px;font-family:inherit;transition:background .2s;margin:0}#changeBgBtn:hover{background:#0000000d}body.dark-mode #changeBgBtn:hover{background:#ffffff1a}.view-transition{transition:transform .32s ease-in-out,opacity .32s ease-in-out;transform:translate(0) scale(1);opacity:1;width:100%}.view-exit{transform:translate(-100%) scale(.98);opacity:0;pointer-events:none}.view-enter-init{transform:translate(100%) scale(.98);opacity:0;pointer-events:none}#date-calculator.hidden{display:none}#closeDateCalcBtn{width:24px;height:24px;font-size:20px;padding:0;display:flex;align-items:center;justify-content:center;margin-left:auto;background:transparent;border:none;color:var(--text-color);cursor:pointer;line-height:1}.date-inputs{display:flex;gap:15px;margin-bottom:20px}.date-group{flex:1;display:flex;flex-direction:column;gap:5px}.date-group label{font-size:.9rem;color:var(--text-color);font-weight:600}.date-group input{padding:10px;border-radius:8px;border:1px solid var(--display-border);background:var(--display-bg);color:var(--text-color);font-size:1.1rem;font-family:inherit;text-align:center;letter-spacing:1px;width:100%;box-sizing:border-box}.date-group input::placeholder{color:#999;opacity:.7}.date-results{display:flex;flex-direction:column;gap:10px}.result-item{display:flex;justify-content:space-between;align-items:center;padding:12px;background:var(--btn-bg);border-radius:8px;box-shadow:0 2px 5px var(--shadow-color)}.result-item .label{font-size:.9rem;color:var(--text-color);opacity:.8}.result-item .value{font-weight:700;color:var(--text-color)}.date-action-container{display:flex;justify-content:center;margin-bottom:20px}.fab-btn{width:56px;height:56px;border-radius:50%;background:var(--accent-bg);color:var(--accent-text);border:none;font-size:24px;cursor:pointer;box-shadow:0 4px 10px #0003;display:flex;align-items:center;justify-content:center;transition:transform .2s,box-shadow .2s,background .3s}.fab-btn:hover{transform:translateY(-2px) scale(1.05);box-shadow:0 6px 14px #00000040}.fab-btn:active{transform:scale(.95);box-shadow:0 2px 5px #0003}.result-item{flex-wrap:wrap}.result-item .label{flex-shrink:0;margin-right:10px}.result-item .value{text-align:right;flex:1;min-width:100px;color:var(--text-color)!important}.input-wrapper{display:flex;align-items:center;gap:8px;position:relative}.calendar-btn{background:none;border:none;font-size:1.5rem;cursor:pointer;padding:0;line-height:1;transition:transform .2s;color:var(--text-color)}.calendar-btn:hover{transform:scale(1.1)}.history-item{background:var(--btn-bg);padding:12px;border-radius:8px;box-shadow:0 2px 5px var(--shadow-color);cursor:pointer;display:flex;flex-direction:column;align-items:flex-end;gap:4px;transition:background .2s ease,transform .1s ease}.history-item:hover{background:var(--btn-action-bg);transform:translateY(-2px)}.currency-converter-container{width:100%;height:100%;padding:10px;box-sizing:border-box;display:flex;flex-direction:column}.currency-card{background:var(--btn-bg);border-radius:16px;padding:24px;box-shadow:0 4px 20px var(--shadow-color);display:flex;flex-direction:column;gap:20px;border:1px solid var(--display-border);transition:background .3s,border-color .3s}body.dark-mode .currency-card{background:#25262b;border-color:#373a40}.currency-input-group label{display:block;margin-bottom:8px;color:var(--text-color);font-size:.9rem;font-weight:600;opacity:.9}.currency-input,.currency-select{width:100%;padding:14px;border-radius:12px;border:1px solid var(--display-border);background:var(--display-bg);color:var(--text-color);font-size:1.1rem;font-weight:500;box-sizing:border-box;transition:border-color .2s,background .2s;outline:none}.currency-input:focus,.currency-select:focus{border-color:var(--btn-action-text)}body.dark-mode .currency-input,body.dark-mode .currency-select{background:#1a1b1e;border-color:#373a40}body.dark-mode .currency-input:focus,body.dark-mode .currency-select:focus{border-color:var(--btn-action-text);background:#141517}.currency-row{display:flex;align-items:center;gap:12px}.currency-swap-btn{margin-top:24px;background:var(--btn-action-bg);border:1px solid var(--display-border);border-radius:50%;width:44px;height:44px;cursor:pointer;color:var(--btn-action-text);font-size:1.3rem;display:flex;align-items:center;justify-content:center;transition:all .2s ease;flex-shrink:0}.currency-swap-btn:hover{background:var(--btn-text);color:var(--bg-color);transform:rotate(180deg)}body.dark-mode .currency-swap-btn{background:#373a40;border-color:#5c5f66;color:#4dabf7}body.dark-mode .currency-swap-btn:hover{background:#4dabf7;color:#fff}.currency-result-area{margin-top:10px;padding:20px;background:var(--display-bg);border-radius:12px;text-align:center;min-height:110px;display:flex;flex-direction:column;justify-content:center;border:1px solid var(--display-border)}body.dark-mode .currency-result-area{background:#1a1b1e;border-color:#373a40}.currency-result-from{font-size:.95rem;color:var(--text-color);opacity:.6;margin-bottom:6px}.currency-result-to{font-size:2.2rem;font-weight:700;color:var(--text-color);letter-spacing:-.5px}.currency-result-to span{font-size:1.1rem;font-weight:500;margin-left:4px;opacity:.8}.currency-rate-info{font-size:.75rem;color:var(--text-color);opacity:.4;margin-top:12px}