:root{--teal: #4ECDC4;--teal-dark: #3BBBB3;--dark-navy: #0D1F2D;--dark-surface: #112233;--dark-card: #1A3040;--dark-header: #0A1A27;--text-primary: #FFFFFF;--text-secondary: rgba(255, 255, 255, .6);--border-color: rgba(255, 255, 255, .08);--shadow-card: 0 8px 32px rgba(0, 0, 0, .4);--font: "Lato", sans-serif;--radius: 20px}[data-theme=light]{--dark-navy: #F2F4F6;--dark-surface: #FFFFFF;--dark-card: #FFFFFF;--dark-header: #FFFFFF;--text-primary: #0D1F2D;--text-secondary: rgba(13, 31, 45, .55);--border-color: rgba(0, 0, 0, .08);--shadow-card: 0 8px 32px rgba(0, 0, 0, .1)}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}html,body{margin:0;padding:0;height:100%;width:100%;font-family:var(--font);background:var(--dark-navy);color:var(--text-primary);-webkit-font-smoothing:antialiased;overscroll-behavior:none}#app{height:100%;width:100%}.app-layout{display:flex;flex-direction:column;height:100%;background:var(--dark-navy)}.app-header{flex-shrink:0;height:60px;display:flex;align-items:center;padding:0 16px;background:var(--dark-header);border-bottom:1px solid var(--border-color);z-index:10;position:relative}#groupPickerContainer{position:absolute;left:50%;transform:translate(-50%)}.header-actions{display:flex;align-items:center;gap:4px;margin-left:auto}.member-counter{font-size:14px;font-weight:500;color:var(--text-secondary)}.icon-btn{background:none;border:none;font-size:18px;cursor:pointer;padding:8px;color:var(--text-secondary);border-radius:50%;transition:background .15s;display:flex;align-items:center;justify-content:center}.icon-btn:hover{background:var(--border-color)}.group-picker{position:relative}.group-picker-active{display:flex;align-items:center;gap:6px;cursor:pointer;-webkit-user-select:none;user-select:none;padding:4px 8px;border-radius:8px;transition:background .15s}.group-picker-active:hover{background:var(--border-color)}.group-name{font-size:17px;font-weight:700;color:var(--text-primary);max-width:65vw;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.group-chevron{font-size:10px;color:var(--text-secondary);transition:transform .2s}.group-picker-active.open .group-chevron{transform:rotate(180deg)}.group-dropdown{position:absolute;top:calc(100% + 8px);left:50%;transform:translate(-50%);background:var(--dark-surface);border:1px solid var(--border-color);border-radius:12px;box-shadow:0 12px 40px #0006;min-width:220px;max-width:90vw;max-height:60vh;overflow-y:auto;z-index:100;text-align:center}.group-dropdown.hidden{display:none}.group-option{padding:13px 16px;cursor:pointer;font-size:15px;font-weight:500;color:var(--text-primary);transition:background .15s}.group-option:hover{background:var(--border-color)}.group-option.selected{color:var(--teal)}.flashcards-main{flex:1;display:flex;min-height:0;position:relative}.scrubber-sidebar{width:44px;flex-shrink:0;display:flex;align-items:stretch;z-index:5}.carousel-area{flex:1;min-width:0;min-height:0;position:relative}.loading-state,.empty-state,.error-state{display:flex;flex-direction:column;align-items:center;justify-content:center;height:100%;gap:12px;color:var(--text-secondary);font-size:15px}.spinner{width:36px;height:36px;border:3px solid var(--border-color);border-top-color:var(--teal);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.login-page{display:flex;flex-direction:column;justify-content:space-between;min-height:100%;height:100dvh;box-sizing:border-box;padding:24px;padding-top:max(20px,env(safe-area-inset-top));padding-bottom:max(24px,env(safe-area-inset-bottom));background:var(--dark-navy);overflow-y:auto}.login-header{margin-top:4vh;text-align:center;flex-shrink:0}.login-logo-img{width:96px;height:96px;display:block;margin:0 auto 12px;border-radius:20px}.login-logo{font-size:32px;font-weight:900;color:var(--teal);letter-spacing:-.5px}.login-actions{margin-bottom:max(72px,calc(11vh + env(safe-area-inset-bottom)));width:100%;max-width:380px;margin-left:auto;margin-right:auto;flex-shrink:0}@media (min-width: 768px){.login-header{margin-top:10vh}.login-logo-img{width:120px;height:120px;margin:0 auto 16px;border-radius:24px}.login-logo{font-size:36px}.login-actions{margin-bottom:20vh}}.btn-primary{display:flex;align-items:center;justify-content:center;gap:10px;width:100%;padding:14px 24px;background:var(--teal);color:#0d1f2d;font-size:15px;font-weight:800;border:none;border-radius:12px;cursor:pointer;transition:background .2s,transform .1s;font-family:var(--font)}.btn-primary:hover{background:var(--teal-dark)}.btn-primary:active{transform:scale(.98)}.login-btn-large{font-size:22px;padding:16px 24px;border-radius:14px}.login-subtitle{margin:10px 0 0;font-size:14px;color:var(--text-secondary);line-height:1.5;text-align:center}.login-actions .login-subtitle{margin:0 0 16px}.login-subtitle strong{color:var(--text-primary)}.login-tab-row{display:flex;gap:8px;margin-bottom:16px;background:var(--dark-surface);border-radius:10px;padding:4px}.login-tab{flex:1;padding:9px;border:none;border-radius:8px;background:transparent;color:var(--text-secondary);font-size:14px;font-weight:600;font-family:var(--font);cursor:pointer;transition:background .15s,color .15s}.login-tab.active{background:var(--dark-card);color:var(--teal)}.login-input{width:100%;padding:14px 16px;margin-bottom:12px;background:var(--dark-surface);border:1px solid var(--border-color);border-radius:12px;color:var(--text-primary);font-size:16px;font-family:var(--font);outline:none;transition:border-color .2s;display:block}.login-input:focus{border-color:var(--teal)}.login-input::placeholder{color:var(--text-secondary)}.login-error{background:#e74c3c1f;border:1px solid rgba(231,76,60,.4);border-radius:10px;color:#e74c3c;font-size:13px;line-height:1.5;padding:10px 14px;margin-bottom:14px}.login-error.hidden{display:none}.otp-input-row{display:flex;gap:8px;justify-content:center;margin-bottom:20px;position:relative}.otp-digit{width:44px;height:56px;display:flex;align-items:center;justify-content:center;font-size:24px;font-weight:700;font-family:var(--font);color:var(--text-primary);background:var(--dark-surface);border:1.5px solid var(--border-color);border-radius:10px;transition:border-color .2s,box-shadow .2s;-webkit-user-select:none;user-select:none;cursor:text}.otp-digit--active{border-color:var(--teal);box-shadow:0 0 0 2px color-mix(in srgb,var(--teal) 25%,transparent)}.otp-digit--filled{border-color:var(--border-color)}.otp-resend-row{display:flex;justify-content:center;align-items:center;gap:10px;margin-top:14px}.otp-divider{color:var(--text-secondary);font-size:13px}.login-link{background:none;border:none;color:var(--teal);font-size:13px;font-family:var(--font);cursor:pointer;padding:0;transition:opacity .15s}.login-link:hover{opacity:.75}.login-link:disabled{color:var(--text-secondary);cursor:default}.profile-list{display:flex;flex-direction:column;gap:10px}.profile-option{display:flex;align-items:center;gap:14px;padding:14px 18px;background:var(--dark-surface);border:1px solid var(--border-color);border-radius:14px;color:var(--text-primary);font-size:16px;font-family:var(--font);font-weight:600;cursor:pointer;transition:border-color .2s,background .15s;text-align:left;width:100%}.profile-option:hover{border-color:var(--teal);background:var(--dark-card)}.profile-avatar{width:40px;height:40px;border-radius:50%;background:var(--dark-card);border:1.5px solid var(--teal);display:flex;align-items:center;justify-content:center;font-size:14px;font-weight:700;color:var(--teal);flex-shrink:0;text-transform:uppercase;letter-spacing:.5px}.profile-name{flex:1}.btn-spinner{display:inline-block;width:20px;height:20px;border:2.5px solid rgba(13,31,45,.35);border-top-color:#0d1f2d;border-radius:50%;animation:spin .7s linear infinite}.carousel-scroller{height:100%;overflow-y:scroll;scroll-snap-type:y mandatory;scroll-behavior:smooth;-webkit-overflow-scrolling:touch;scrollbar-width:none;display:flex;flex-direction:column;align-items:center;padding-top:15vh;padding-bottom:15vh}.carousel-scroller::-webkit-scrollbar{display:none}.card-wrapper{width:100%;height:75vh;display:flex;align-items:center;justify-content:center;scroll-snap-align:center;scroll-snap-stop:always;padding:32px 16px 32px 8px;transition:opacity .3s}.flashcard{width:100%;max-width:360px;background:var(--dark-card);border-radius:var(--radius);box-shadow:var(--shadow-card);overflow:hidden;border:2px solid transparent;transition:border-color .3s,transform .3s;cursor:pointer;-webkit-user-select:none;user-select:none}.card-photo-wrap{width:100%;aspect-ratio:1 / 1;overflow:hidden;background:var(--dark-surface);position:relative}.card-avatar{width:100%;height:100%;object-fit:cover;display:block}.card-avatar--deferred{width:100%;height:100%;display:block;background:var(--dark-surface)}.card-avatar-placeholder{width:100%;height:100%;display:flex;align-items:center;justify-content:center;font-size:72px;font-weight:900;color:var(--teal);background:linear-gradient(135deg,var(--dark-surface),var(--dark-card));letter-spacing:-2px}.card-info{padding:16px 16px 20px;text-align:center}.card-name{margin:0;font-size:20px;font-weight:700;color:var(--text-primary);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.scrubber-list{display:flex;flex-direction:column;align-items:center;justify-content:center;height:100%;width:100%;padding:10px 0;font-size:13px;font-weight:700;color:var(--text-secondary);background:#0000001a;border-right:1px solid var(--border-color)}.scrubber-letter{flex:1;display:flex;align-items:center;justify-content:center;width:100%;cursor:default;opacity:.3;transition:all .2s;-webkit-user-select:none;user-select:none}.scrubber-letter.has-members{opacity:.7;color:var(--text-primary);cursor:pointer}.scrubber-letter.has-members:hover{opacity:1}.scrubber-letter.is-active{color:var(--teal);opacity:1;font-size:16px;font-weight:900;transform:scale(1.2)}