:root{--bg: #f4f6f9;--card: #ffffff;--primary: #6d5efc;--primary-dark: #5b4ee0;--accent: #a855f7;--grad: linear-gradient(135deg, #6d5efc 0%, #a855f7 100%);--text: #1e2330;--muted: #6b7280;--border: #e7e9f0;--danger: #ef4456}*{box-sizing:border-box}body{margin:0;background:linear-gradient(180deg,#f7f8fc,#eef0f8);background-attachment:fixed;color:var(--text);font-family:Noto Sans JP,system-ui,-apple-system,Hiragino Kaku Gothic ProN,Meiryo,sans-serif;line-height:1.65;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}.container{max-width:720px;margin:0 auto;padding:16px 14px 64px}.app-header{padding:8px 0 16px}.app-header h1{font-size:1.4rem;margin:0 0 8px}.student .app-header{margin:4px 0 18px;padding:22px 22px 20px;background:var(--grad);border-radius:20px;color:#fff;box-shadow:0 12px 30px -10px #6d5efc8c;position:relative;overflow:hidden}.student .app-header:after{content:"";position:absolute;top:-40px;right:-30px;width:160px;height:160px;background:#ffffff24;border-radius:50%}.student .app-header h1{font-size:1.5rem;font-weight:800;letter-spacing:.02em;margin:0;position:relative}.student .session-title{display:inline-block;margin:12px 0 0;padding:5px 14px;background:#ffffff38;border-radius:999px;color:#fff;font-weight:600;font-size:.92rem;position:relative;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px)}.app-header.admin{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:8px}.admin-bar{display:flex;align-items:center;gap:10px}.role-badge{font-size:.78rem;background:#eef2ff;color:var(--primary-dark);padding:3px 10px;border-radius:999px}.session-title{margin:4px 0 0;color:var(--muted);font-weight:600}.session-select{width:100%;padding:8px;border-radius:8px;border:1px solid var(--border);margin-bottom:6px}.card{background:var(--card);border:1px solid var(--border);border-radius:14px;padding:16px;margin-bottom:12px;box-shadow:0 2px 10px -4px #1e233014}.form textarea,.form input,.toolbar select{width:100%;padding:10px;border:1px solid var(--border);border-radius:8px;font-size:1rem;font-family:inherit}.form textarea{resize:vertical;margin-bottom:10px}.form-row{display:flex;gap:8px;margin-top:8px}.form-row input{flex:1}.form-message{margin:10px 0 0;font-size:.9rem;color:var(--primary-dark)}button{cursor:pointer;border:none;background:var(--primary);color:#fff;padding:10px 16px;border-radius:10px;font-size:.95rem;font-family:inherit;font-weight:600;white-space:nowrap;transition:background .15s,transform .08s,box-shadow .15s}button:hover{background:var(--primary-dark)}button:active{transform:translateY(1px)}button:focus-visible{outline:2px solid var(--primary);outline-offset:2px}button:disabled{background:#9ca3af;cursor:not-allowed}button.danger{background:var(--danger)}button.danger:hover{background:#b91c1c}.link-btn{background:transparent;color:var(--muted);padding:4px 6px}.link-btn:hover{background:transparent;color:var(--text)}.list-header{display:flex;align-items:center;justify-content:space-between;margin:14px 2px 8px;font-weight:700}.sort-toggle{display:flex;gap:4px}.sort-toggle button{background:#fff;color:var(--muted);border:1px solid var(--border);padding:5px 12px;font-size:.85rem}.sort-toggle button{border-radius:999px;transition:all .15s}.sort-toggle button.active{background:var(--primary);color:#fff;border-color:var(--primary)}.container.student{padding-bottom:250px}.container.student.tech{padding-bottom:40px}.tech-card h2{font-size:1.15rem;margin:0 0 4px}.tech-card h3{font-size:.95rem;margin:16px 0 6px;color:var(--primary-dark)}.tech-lead{color:var(--muted);font-size:.9rem;margin:0 0 8px}.tech-list{margin:0;padding-left:1.2em}.tech-list li{margin:5px 0;font-size:.92rem}.tech-card code{background:#f3f4f6;padding:1px 5px;border-radius:4px;font-size:.85em}.tech-diagram{background:#0f172a;color:#e2e8f0;padding:12px 14px;border-radius:10px;font-size:.8rem;line-height:1.5;overflow-x:auto;white-space:pre;margin:0}.composer{position:fixed;left:0;right:0;bottom:0;margin:0 auto;max-width:720px;padding:10px 14px calc(10px + env(safe-area-inset-bottom,0px));background:#fffffff5;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);border-top:1px solid var(--border);box-shadow:0 -4px 20px #00000014;z-index:20}.composer-nick{width:100%;padding:7px 10px;border:1px solid var(--border);border-radius:8px;font-size:.85rem;margin-bottom:8px;font-family:inherit}.composer-row{display:flex;gap:8px;align-items:flex-end}.composer-nick:focus,.composer-row textarea:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #6d5efc26}.composer-row textarea{flex:1;padding:12px;border:1px solid var(--border);border-radius:12px;font-size:1rem;font-family:inherit;resize:vertical;min-height:72px;max-height:240px;line-height:1.5;transition:border-color .15s,box-shadow .15s}.composer-row button{border-radius:12px;padding:12px 20px;align-self:stretch;background:var(--grad);box-shadow:0 6px 16px -6px #6d5efc99}.composer-row button:hover{filter:brightness(1.05)}.composer-row button:disabled{background:#c4c8d4;box-shadow:none;filter:none}.composer .form-message{margin:8px 2px 0}.composer-note{margin:4px 2px;text-align:center;color:var(--muted);font-size:.9rem}.composer-warn{margin:6px 2px 0;font-size:.72rem;color:#9aa0ac;line-height:1.4}.notice-card{text-align:center;color:var(--muted);margin-top:24px;line-height:1.8}.qr-caption{font-size:.75rem;color:var(--muted);margin-top:6px}.celebrate{position:fixed;top:0;right:0;bottom:0;left:0;z-index:100;pointer-events:none;overflow:hidden}.celebrate-banner{position:absolute;top:36%;left:50%;transform:translate(-50%,-50%);background:linear-gradient(135deg,#f59e0b,#ef4444,#8b5cf6);color:#fff;font-weight:800;font-size:1.5rem;padding:16px 28px;border-radius:16px;box-shadow:0 12px 44px #0000004d;text-align:center;white-space:nowrap;animation:celebratePop 2.6s ease forwards}@keyframes celebratePop{0%{transform:translate(-50%,-50%) scale(.3) rotate(-6deg);opacity:0}15%{transform:translate(-50%,-50%) scale(1.12) rotate(3deg);opacity:1}28%{transform:translate(-50%,-50%) scale(1) rotate(0)}80%{opacity:1}to{opacity:0;transform:translate(-50%,-68%) scale(1)}}.confetti{position:absolute;top:-48px;will-change:transform;animation-name:confettiFall;animation-timing-function:linear;animation-iteration-count:1}@keyframes confettiFall{0%{transform:translateY(-48px) rotate(0);opacity:1}to{transform:translateY(106vh) rotate(600deg);opacity:1}}.question-list,.session-list{list-style:none;padding:0;margin:0}.empty{text-align:center;color:var(--muted);padding:44px 20px;background:#fff;border:1px dashed var(--border);border-radius:14px;line-height:1.9}.student .question{animation:cardIn .28s ease both;transition:transform .12s,box-shadow .2s}.student .question:hover{transform:translateY(-2px);box-shadow:0 8px 22px -10px #1e233038}@keyframes cardIn{0%{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}.question-body{margin:0 0 12px;font-size:1.02rem;white-space:pre-wrap;word-break:break-word}.question-meta{display:flex;align-items:center;flex-wrap:wrap;gap:8px 12px;font-size:.85rem;color:var(--muted)}.device-info{margin-top:4px;font-size:.68rem;color:#aeb2bd;word-break:break-all;line-height:1.4}.question-meta .device-info{margin-top:0}.student .question-meta{flex-wrap:nowrap;gap:8px}.student .question-meta .nickname{flex-shrink:0;max-width:8em;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.student .question-meta .time{flex-shrink:0;margin-left:0;white-space:nowrap}.student .question-meta .device-info{flex:1 1 auto;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;word-break:normal}.student .question-meta .like-btn{flex-shrink:0;margin-left:auto}.question-meta .nickname{font-weight:600;color:var(--text)}.question-meta .time{margin-left:auto;font-size:.78rem}.like-btn{background:#fff;color:var(--danger);border:1px solid var(--border);border-radius:999px;padding:5px 14px;margin-left:auto;font-weight:700;transition:all .15s}.like-btn:not(.liked):hover{background:#fff1f3;border-color:#ffd2da}.like-btn.liked{background:#ffe4e9;border-color:#ffc4cf;animation:likePop .35s ease}@keyframes likePop{0%{transform:scale(1)}40%{transform:scale(1.18)}to{transform:scale(1)}}.banner,.tag{background:#fef3c7;color:#92400e}.banner{padding:10px 14px;border-radius:8px;margin-bottom:12px;font-size:.9rem}.tag{font-size:.72rem;padding:2px 8px;border-radius:999px}.tabs{display:flex;gap:4px;margin-bottom:16px;padding:4px;background:#eceef6;border-radius:12px}.tabs button{flex:1;background:transparent;color:var(--muted);border:none;border-radius:9px;font-weight:600;padding:9px 12px}.tabs button:hover{background:#fff9;color:var(--text)}.tabs button.active{background:#fff;color:var(--primary-dark);box-shadow:0 2px 6px -2px #1e23302e}.toolbar{display:flex;flex-wrap:wrap;gap:8px;align-items:center}.toolbar select{flex:1;min-width:140px}.export-btn{display:inline-block;background:#059669;color:#fff;padding:9px 14px;border-radius:8px;text-decoration:none;font-size:.9rem}.export-btn:hover{background:#047857}.question.admin.hidden-q{opacity:.6}.admin-actions{display:flex;gap:8px;margin-top:10px}.admin-actions button{background:#fff;color:var(--text);border:1px solid var(--border);padding:6px 12px;font-size:.85rem}.admin-actions button.danger{background:#fff;color:var(--danger);border-color:#fecaca}.session-card{display:flex;gap:14px;align-items:flex-start;justify-content:space-between}.session-info{flex:1;min-width:0}.session-name{font-weight:700;display:flex;align-items:center;gap:8px}.status{font-size:.72rem;padding:2px 8px;border-radius:999px}.status.open{background:#dcfce7;color:#166534}.status.closed{background:#f3f4f6;color:var(--muted)}.session-sub{font-size:.85rem;color:var(--muted)}.qr-url{font-size:.75rem;word-break:break-all;margin:6px 0}.poll-count{font-size:.85rem;margin:4px 0 2px}.poll-count strong{font-size:1rem}.poll-note{display:block;font-size:.7rem;color:var(--muted)}.session-actions{display:flex;gap:8px;margin-top:8px}.session-actions button{background:#fff;color:var(--text);border:1px solid var(--border);padding:6px 12px;font-size:.85rem}.session-actions button.danger{color:var(--danger);border-color:#fecaca}.qr{width:110px;height:110px;border-radius:8px;border:1px solid var(--border)}