*{margin:0;padding:0;box-sizing:border-box}
body{font-family:-apple-system,BlinkMacSystemFont,'Apple SD Gothic Neo',sans-serif;background:#f0f2f5;color:#1a1a1a;min-height:100vh}
.hidden{display:none!important}
.login-page{display:flex;align-items:center;justify-content:center;min-height:100vh;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%)}
.login-box{background:#fff;border-radius:20px;padding:48px 40px;width:380px;max-width:90vw;box-shadow:0 20px 60px rgba(0,0,0,.3);text-align:center}
.login-box h1{font-size:28px;margin-bottom:8px}
.login-box p{color:#888;margin-bottom:28px;font-size:14px}
.login-box input{width:100%;padding:14px 16px;border:2px solid #e0e0e0;border-radius:12px;font-size:16px;margin-bottom:12px;outline:none;transition:border .2s}
.login-box input:focus{border-color:#667eea}
.login-box button{width:100%;padding:14px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:12px;font-size:16px;font-weight:600;cursor:pointer;margin-top:8px}
.login-box button:active{transform:scale(.98)}
.login-error{color:#e74c3c;font-size:13px;margin-top:12px;min-height:20px}
.app{display:flex;min-height:100vh}
.sidebar{width:240px;background:#fff;border-right:1px solid #e8e8e8;padding:20px 0;display:flex;flex-direction:column;position:fixed;top:0;left:0;bottom:0}
.sidebar-logo{padding:0 24px 20px;font-size:22px;font-weight:700;border-bottom:1px solid #f0f0f0;margin-bottom:12px}
.sidebar-nav{flex:1}
.sidebar-nav a{display:flex;align-items:center;gap:10px;padding:12px 24px;color:#555;text-decoration:none;font-size:15px;transition:all .15s;cursor:pointer}
.sidebar-nav a:hover{background:#f5f3ff;color:#667eea}
.sidebar-nav a.active{background:#f5f3ff;color:#667eea;font-weight:600}
.sidebar-nav a .icon{font-size:18px;width:24px;text-align:center}
.sidebar-user{padding:16px 24px;border-top:1px solid #f0f0f0;font-size:13px;color:#888}
.sidebar-user .name{font-weight:600;color:#333;font-size:14px}
.sidebar-user .logout{color:#667eea;cursor:pointer;margin-top:6px;display:block;font-size:12px}
.main{flex:1;margin-left:240px;padding:24px 32px;max-width:960px}
.page-title{font-size:24px;font-weight:700;margin-bottom:20px}
.card{background:#fff;border-radius:16px;padding:24px;margin-bottom:16px;box-shadow:0 1px 3px rgba(0,0,0,.06)}
.card h3{font-size:16px;margin-bottom:12px}
.subject-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:12px}
.subject-card{background:#fff;border-radius:16px;padding:20px;text-align:center;cursor:pointer;transition:all .2s;border:2px solid transparent;box-shadow:0 1px 3px rgba(0,0,0,.06)}
.subject-card:hover{border-color:#667eea;transform:translateY(-2px)}
.subject-card .emoji{font-size:32px;margin-bottom:8px}
.subject-card .name{font-size:14px;font-weight:600}
.subject-card .progress{font-size:12px;color:#888;margin-top:4px}
.unit-list{list-style:none}
.unit-list li{padding:14px 16px;border-bottom:1px solid #f0f0f0;cursor:pointer;display:flex;justify-content:space-between;align-items:center;transition:background .15s}
.unit-list li:hover{background:#f9f7ff}
.unit-list li:last-child{border-bottom:none}
.unit-list li .name{font-weight:500}
.unit-list li .count{font-size:12px;color:#888;background:#f0f0f0;padding:2px 10px;border-radius:20px}
.problem-area{background:#fff;border-radius:16px;padding:24px;margin-bottom:16px}
.problem-text{font-size:18px;line-height:1.8;margin-bottom:16px;white-space:pre-wrap}
.problem-meta{font-size:12px;color:#888;margin-bottom:12px}
.canvas-area{border:2px dashed #ddd;border-radius:12px;background:#fafafa;touch-action:none}
.canvas-area canvas{width:100%;display:block}
.btn-row{display:flex;gap:8px;margin-top:12px;flex-wrap:wrap}
.btn{padding:10px 20px;border-radius:10px;border:none;font-size:14px;font-weight:600;cursor:pointer;transition:all .15s}
.btn-primary{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff}
.btn-secondary{background:#f0f0f0;color:#555}
.btn-success{background:#34d399;color:#fff}
.btn:active{transform:scale(.97)}
.result-card{text-align:center;padding:32px}
.result-icon{font-size:64px;margin-bottom:16px}
.result-score{font-size:36px;font-weight:700;color:#667eea}
.result-feedback{font-size:16px;color:#555;margin:12px 0}
.explanation{background:#f9f7ff;border-radius:12px;padding:16px;text-align:left;margin:16px 0;font-size:14px;line-height:1.8;white-space:pre-wrap}
.alternatives{background:#fff8e6;border-radius:12px;padding:16px;text-align:left;margin:12px 0;font-size:13px;line-height:1.8}
select{padding:8px 12px;border:2px solid #e0e0e0;border-radius:10px;font-size:14px;outline:none;background:#fff}
select:focus{border-color:#667eea}
.breadcrumb{font-size:13px;color:#888;margin-bottom:16px}
.breadcrumb a{color:#667eea;text-decoration:none;cursor:pointer}
.breadcrumb a:hover{text-decoration:underline}
.loading{text-align:center;padding:40px;color:#888}
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,.4);display:flex;align-items:center;justify-content:center;z-index:100}
.modal{background:#fff;border-radius:20px;padding:32px;width:600px;max-width:90vw;max-height:80vh;overflow-y:auto}
.modal h2{margin-bottom:16px}
.modal-close{float:right;background:none;border:none;font-size:24px;cursor:pointer;color:#888}
.chart-bar{display:flex;align-items:end;gap:8px;height:120px;padding:12px 0}
.chart-bar .bar{flex:1;background:linear-gradient(180deg,#667eea,#764ba2);border-radius:6px 6px 0 0;min-width:30px;position:relative;transition:height .3s}
.chart-bar .bar-label{position:absolute;bottom:-20px;left:50%;transform:translateX(-50%);font-size:10px;color:#888;white-space:nowrap}
.chart-bar .bar-value{position:absolute;top:-18px;left:50%;transform:translateX(-50%);font-size:10px;font-weight:600;color:#667eea}
.generate-form{display:flex;flex-direction:column;gap:12px;max-width:400px}
.generate-form label{font-size:13px;font-weight:600;color:#555}
.generate-form select,.generate-form input{padding:10px;border:2px solid #e0e0e0;border-radius:10px;font-size:14px}
.history-item{padding:16px;border-bottom:1px solid #f0f0f0;display:flex;gap:16px;align-items:center;cursor:pointer;transition:background .15s}
.history-item:hover{background:#f9f7ff}
.history-item:last-child{border-bottom:none}
.history-badge{width:44px;height:44px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:18px;flex-shrink:0}
.history-badge.correct{background:#d1fae5}
.history-badge.wrong{background:#fee2e2}
.history-info{flex:1}
.history-info .q{font-size:14px;font-weight:500;margin-bottom:4px}
.history-info .meta{font-size:12px;color:#888}
.history-score{font-size:14px;font-weight:600}
.toolbar{display:flex;gap:8px;align-items:center;margin-bottom:16px;flex-wrap:wrap}
/* Form Groups */
.form-group{display:flex;flex-direction:column;gap:6px}
.form-group label{font-size:13px;font-weight:600;color:#555}
.form-group input,.form-group select{padding:10px;border:2px solid #e0e0e0;border-radius:10px;font-size:14px;outline:none}
.form-group input:focus,.form-group select:focus{border-color:#667eea}
/* Model Select */
.model-select{display:flex;gap:10px;flex-wrap:wrap}
.model-option{display:flex;align-items:center;gap:6px;padding:10px 16px;border:2px solid #e0e0e0;border-radius:12px;cursor:pointer;transition:all .2s;font-size:14px}
.model-option.selected{border-color:#667eea;background:#f5f3ff}
.model-option input{display:none}
.model-badge{font-size:18px}
/* Review Page */
.review-stats{padding:20px}
.stat-row{display:flex;gap:16px;justify-content:space-around;margin-bottom:16px}
.stat-item{text-align:center}
.stat-value{font-size:32px;font-weight:700;color:#667eea}
.stat-label{font-size:12px;color:#888;margin-top:4px}
.subject-breakdown{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}
.subject-tag{background:#f0f2f5;padding:4px 12px;border-radius:20px;font-size:12px;color:#555}
.review-list{margin-top:12px}
.review-item{padding:16px;border-bottom:1px solid #f0f0f0;cursor:pointer;transition:background .15s}
.review-item:hover{background:#f9f7ff}
.review-item:last-child{border-bottom:none}
.review-subject{font-size:12px;font-weight:600;color:#667eea;margin-bottom:4px}
.review-question{font-size:14px;font-weight:500;margin-bottom:4px}
.review-meta{font-size:11px;color:#888}
/* Empty State */
.empty-state{text-align:center;padding:32px 16px}
.empty-icon{font-size:48px;margin-bottom:12px}
.empty-text{font-size:16px;font-weight:600;color:#333;margin-bottom:8px}
.empty-sub{font-size:13px;color:#888;margin-bottom:16px}
/* Members */
.members-list{display:flex;flex-direction:column;gap:12px}
.member-card{display:flex;align-items:center;gap:16px;padding:16px;border:1px solid #eee;border-radius:12px;transition:all .2s}
.member-card:hover{box-shadow:0 2px 8px rgba(0,0,0,.08)}
.member-avatar{font-size:32px;flex-shrink:0}
.member-info{flex:1}
.member-name{font-size:15px;font-weight:600;margin-bottom:2px}
.member-meta{font-size:12px;color:#888}
.member-actions{display:flex;gap:6px}
.btn-sm{padding:6px 14px;border-radius:8px;border:none;font-size:12px;font-weight:600;cursor:pointer}
.btn-danger{background:#fee2e2;color:#e74c3c}
.btn-success{background:#d1fae5;color:#059669}
/* Generate Result */
.gen-result{border:2px solid #d1fae5}
.gen-model-badge{display:inline-block;padding:4px 12px;background:#f0f2f5;border-radius:20px;font-size:12px;margin:8px 0}
.gen-item{padding:10px 0;border-bottom:1px solid #f0f0f0;font-size:14px}
.gen-item:last-child{border-bottom:none}
.gen-error{border:2px solid #fee2e2;color:#e74c3c}
/* Modal */
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,.4);display:flex;align-items:center;justify-content:center;z-index:100}
.modal{background:#fff;border-radius:20px;padding:32px;width:480px;max-width:90vw;max-height:80vh;overflow-y:auto}
.modal h2{margin-bottom:20px;font-size:20px}
.modal-close{float:right;background:none;border:none;font-size:24px;cursor:pointer;color:#888}
/* Result with review context */
.result-review-badge{display:inline-block;padding:4px 12px;background:#fef3c7;color:#d97706;border-radius:20px;font-size:12px;font-weight:600;margin-bottom:8px}
@media(max-width:768px){
  .sidebar{display:none}
  .main{margin-left:0;padding:16px}
  .mobile-nav{display:flex!important}
  .stat-row{flex-direction:column;gap:8px}
  .model-select{flex-direction:column}
  .member-card{flex-direction:column;align-items:flex-start}
  .member-actions{width:100%}
}
.mobile-nav{display:none;position:fixed;bottom:0;left:0;right:0;background:#fff;border-top:1px solid #e8e8e8;justify-content:space-around;padding:8px 0;z-index:50;padding-bottom:env(safe-area-inset-bottom)}
.mobile-nav a{display:flex;flex-direction:column;align-items:center;font-size:9px;color:#888;text-decoration:none;padding:4px;cursor:pointer}
.mobile-nav a.active{color:#667eea}
.mobile-nav a .icon{font-size:20px}
/* Mode Toggle (Keyboard/Pencil) */
.mode-toggle{display:flex;gap:12px;margin-bottom:16px}
.radio-btn{display:flex;align-items:center;gap:6px;padding:10px 20px;border:2px solid #e0e0e0;border-radius:12px;cursor:pointer;font-size:14px;transition:all .2s;user-select:none}
.radio-btn:has(input:checked){border-color:#667eea;background:#f5f3ff;color:#667eea;font-weight:600}
.radio-btn input[type="radio"]{display:none}
/* Answer Textarea */
.answer-textarea{width:100%;min-height:120px;padding:16px;border:2px solid #e0e0e0;border-radius:12px;font-size:16px;line-height:1.6;resize:vertical;outline:none;font-family:inherit}
.answer-textarea:focus{border-color:#667eea}
/* My Answer Display */
.my-answer{padding:16px;background:#f9f7ff;border-radius:12px;min-height:60px}
.my-answer .answer-text{font-size:16px;line-height:1.6;white-space:pre-wrap}
.correct-answer{padding:16px;background:#d1fae5;border-radius:12px;font-size:16px;font-weight:600;line-height:1.6}
/* Choice Options (객관식 라디오박스) */
.choice-area{display:flex;flex-direction:column;gap:10px;margin-bottom:8px}
.choice-option{display:flex;align-items:center;gap:12px;padding:14px 18px;border:2px solid #e0e0e0;border-radius:12px;cursor:pointer;font-size:16px;transition:all .2s;user-select:none}
.choice-option:hover{border-color:#a5b4fc;background:#faf9ff}
.choice-option:has(input:checked){border-color:#667eea;background:#f5f3ff;font-weight:600}
.choice-option input[type="radio"]{width:20px;height:20px;accent-color:#667eea;flex-shrink:0}
/* Hint text */
.hint-text{font-size:13px;color:#888}
/* AI extra explanation */
.explanation.ai-extra{background:#fffbeb;border:1px solid #fde68a}
.ai-badge{display:inline-block;font-size:12px;font-weight:700;color:#d97706;background:#fef3c7;padding:4px 12px;border-radius:20px;margin-bottom:10px}
/* Selected subject card */
.subject-card.selected{border-color:#667eea;background:#f5f3ff}