:root{--primary: #275441;--primary-dark: #1a3a2d;--primary-light: #3d7a5e;--background: #ded9d5;--background-light: #f5f3f1;--surface: #ffffff;--border: #c5c0bc;--border-light: #e5e2df;--text-primary: #1a1a1a;--text-secondary: #5a5a5a;--text-muted: #8a8a8a;--success: #3d8a5a;--error: #d94545;--warning: #c98a2e;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 16px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Inter,-apple-system,BlinkMacSystemFont,sans-serif;background:var(--background);color:var(--text-primary);min-height:100vh;line-height:1.6}.app{min-height:100vh;display:flex;flex-direction:column}.header{background:var(--primary);padding:0 48px;height:72px;display:flex;align-items:center;justify-content:space-between}.logo{display:flex;align-items:center;gap:12px}.logo-icon{width:28px;height:28px;color:#fff}.logo-text{color:#fff;font-size:22px;font-weight:600}.user-area{display:flex;align-items:center;gap:12px;color:#fff}.user-icon{width:32px;height:32px}.user-name{font-size:14px;font-weight:500}.main-content{flex:1;display:flex;gap:32px;padding:48px;max-width:1440px;margin:0 auto;width:100%}.form-panel{width:420px;flex-shrink:0;background:var(--surface);border-radius:var(--radius-lg);padding:32px;box-shadow:0 4px 20px #0000000f;height:fit-content}.output-panel{flex:1;background:var(--surface);border-radius:var(--radius-lg);padding:32px;box-shadow:0 4px 20px #0000000f;min-height:500px}.panel-title{font-size:24px;font-weight:600;color:var(--text-primary);margin-bottom:8px}.panel-subtitle{font-size:14px;color:var(--text-secondary);line-height:1.5;margin-bottom:24px}.form-field{margin-bottom:20px}.form-label{display:block;font-size:14px;font-weight:500;color:var(--text-primary);margin-bottom:8px}.form-hint{font-size:12px;color:var(--text-muted);margin-bottom:12px}.form-input,.form-select{width:100%;height:48px;padding:0 16px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--background-light);color:var(--text-primary);font-size:14px;transition:border-color .2s ease,box-shadow .2s ease}.form-input:focus,.form-select:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #2754411a}.form-select{cursor:pointer;-webkit-appearance:none;-moz-appearance:none;appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%235a5a5a' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 16px center;padding-right:40px}.lesson-type-options{display:flex;flex-direction:column;gap:10px}.lesson-type-option{display:flex;align-items:center;gap:12px;padding:14px 16px;background:var(--background-light);border:1px solid var(--border);border-radius:var(--radius-md);cursor:pointer;transition:all .2s ease}.lesson-type-option:hover{border-color:var(--primary-light)}.lesson-type-option.selected{border-color:var(--primary);background:#2754410d}.lesson-type-checkbox{width:20px;height:20px;border:2px solid var(--border);border-radius:4px;display:flex;align-items:center;justify-content:center;flex-shrink:0;transition:all .2s ease}.lesson-type-option.selected .lesson-type-checkbox{background:var(--primary);border-color:var(--primary)}.lesson-type-checkbox svg{width:14px;height:14px;color:#fff;opacity:0;transition:opacity .2s ease}.lesson-type-option.selected .lesson-type-checkbox svg{opacity:1}.lesson-type-label{font-size:14px;font-weight:500;color:var(--text-primary);text-transform:capitalize}.generate-btn{width:100%;height:52px;border:none;border-radius:var(--radius-md);background:var(--primary);color:#fff;font-size:16px;font-weight:600;cursor:pointer;display:flex;align-items:center;justify-content:center;gap:10px;transition:all .2s ease;margin-top:24px}.generate-btn:hover:not(:disabled){background:var(--primary-dark);transform:translateY(-1px);box-shadow:0 4px 12px #2754414d}.generate-btn:disabled{opacity:.6;cursor:not-allowed}.generate-btn svg{width:20px;height:20px}.output-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}.output-title{font-size:24px;font-weight:600;color:var(--text-primary)}.output-actions{display:flex;gap:12px}.action-btn{width:36px;height:36px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--background-light);color:var(--text-secondary);cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s ease}.action-btn:hover{border-color:var(--primary);color:var(--primary)}.action-btn.save-btn{background:var(--primary);color:#fff;border-color:var(--primary)}.action-btn.save-btn:hover{background:#1e3d2f;border-color:#1e3d2f;color:#fff}.action-btn.cancel-btn{background:#d94545;color:#fff;border-color:#d94545}.action-btn.cancel-btn:hover{background:#b83939;border-color:#b83939;color:#fff}.output-divider{height:1px;background:var(--border-light);margin-bottom:16px}.lesson-meta{display:flex;gap:24px;margin-bottom:16px}.meta-item{display:flex;align-items:center;gap:8px;font-size:14px;color:var(--text-secondary)}.meta-item svg{width:16px;height:16px;color:var(--primary)}.usage-metrics{display:flex;gap:20px;padding:12px 16px;background:#2754410d;border-radius:8px;margin-bottom:24px;border:1px solid rgba(39,84,65,.1)}.metric-item{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--text-secondary);font-weight:500}.metric-item svg{width:16px;height:16px;color:var(--primary);opacity:.8}.metric-item span{font-family:SF Mono,Monaco,Inconsolata,Roboto Mono,monospace}.content-section{background:var(--background-light);border-radius:12px;padding:20px;margin-bottom:24px}.section-header{display:flex;align-items:center;gap:8px;margin-bottom:12px}.section-icon{width:20px;height:20px;color:var(--primary)}.section-title{font-size:16px;font-weight:600;color:var(--text-primary)}.section-content{font-size:14px;color:var(--text-secondary);line-height:1.7}.section-content ul,.section-content ol{margin-left:20px;margin-top:8px}.section-content li{margin-bottom:6px}.lesson-plan{font-size:14px;color:var(--text-secondary);line-height:1.7;transition:all .3s ease}.lesson-plan.editing{border:2px solid var(--primary);border-radius:8px;padding:16px;background:#fafafa;outline:none}.lesson-plan.editing:focus{border-color:var(--primary);box-shadow:0 0 0 3px #2754411a}.lesson-plan h2{font-size:18px;font-weight:600;color:var(--text-primary);margin:24px 0 12px;padding-bottom:8px;border-bottom:2px solid var(--primary)}.lesson-plan h2:first-child{margin-top:0}.lesson-plan h3{font-size:16px;font-weight:600;color:var(--text-primary);margin:16px 0 8px}.lesson-plan p{margin-bottom:12px}.lesson-plan ul,.lesson-plan ol{margin-left:24px;margin-bottom:12px}.lesson-plan li{margin-bottom:6px}.lesson-plan strong{color:var(--text-primary);font-weight:600}.teacher-resources-card{background:var(--background-light);border-radius:12px;margin-bottom:24px;overflow:hidden}.teacher-resources-header{display:flex;align-items:center;justify-content:space-between;padding:20px;cursor:pointer;-webkit-user-select:none;user-select:none}.teacher-resources-header:hover{background:#2754410d}.resource-badge{display:inline-block;padding:6px 12px;background:#2754411a;border-radius:6px}.resource-badge span{font-size:14px;font-weight:600;color:var(--primary)}.chevron-icon{transition:transform .3s ease;color:var(--primary);flex-shrink:0}.chevron-icon.expanded{transform:rotate(180deg)}.teacher-resources-content{display:flex;flex-direction:column;gap:16px;padding:0 20px 20px}.resource-item-card{background:#fff;border-radius:8px;overflow:hidden}.resource-item-header{display:flex;align-items:center;justify-content:space-between;padding:12px;cursor:pointer;-webkit-user-select:none;user-select:none}.resource-item-header:hover{background:#2754410d}.resource-item-header-left{display:flex;align-items:center;gap:8px;font-size:14px;font-weight:500;color:var(--text-primary);flex:1}.resource-item-header-left svg{width:16px;height:16px;color:var(--primary);flex-shrink:0}.resource-chevron{transition:transform .3s ease;color:var(--primary);flex-shrink:0}.resource-chevron.expanded{transform:rotate(180deg)}.track-badge{display:inline-block;padding:4px 8px;background:#2754411a;border-radius:4px;font-size:12px;font-weight:600;color:var(--primary);margin-left:auto}.video-container{position:relative;width:100%;padding-bottom:56.25%;background:#000;border-radius:0 0 8px 8px;overflow:hidden;border-top:1px solid #e5e5e5}.video-container iframe{position:absolute;top:0;left:0;width:100%;height:100%;border:none}.audio-player-container{padding:12px;border-top:1px solid #e5e5e5;border-radius:0 0 8px 8px;background:#fff}.audio-player{width:100%;height:48px}.resource-error{padding:16px;background:#d945450d;border:1px solid #d94545;border-radius:8px}.resource-error p{font-size:14px;font-weight:500;margin-bottom:4px}.resource-error span{font-size:12px;color:#d94545}.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;height:100%;min-height:400px;color:var(--text-muted);text-align:center}.empty-state svg{width:64px;height:64px;margin-bottom:16px;opacity:.5}.empty-state p{font-size:16px;margin-bottom:8px}.empty-state span{font-size:14px}.status{padding:12px 16px;border-radius:var(--radius-md);margin-top:16px;display:flex;align-items:center;gap:10px;font-size:14px}.status.success{background:#3d8a5a1a;border:1px solid var(--success);color:var(--success)}.status.error{background:#d945451a;border:1px solid var(--error);color:var(--error)}.status.loading{background:#2754411a;border:1px solid var(--primary);color:var(--primary)}.spinner{width:18px;height:18px;border:2px solid var(--primary);border-top-color:transparent;border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.secondary-nav{display:flex;gap:8px;margin-bottom:24px}.nav-btn{padding:10px 20px;border:1px solid var(--border);border-radius:var(--radius-md);background:var(--background-light);color:var(--text-secondary);font-size:14px;font-weight:500;cursor:pointer;transition:all .2s ease}.nav-btn:hover{border-color:var(--primary-light);color:var(--text-primary)}.nav-btn.active{background:var(--primary);border-color:var(--primary);color:#fff}.file-upload{border:2px dashed var(--border);border-radius:12px;padding:40px;text-align:center;cursor:pointer;transition:all .2s ease;background:var(--background-light);margin-bottom:24px}.file-upload:hover{border-color:var(--primary);background:#27544105}.file-upload.has-file{border-color:var(--success);background:#3d8a5a0d}.file-upload-icon{font-size:48px;margin-bottom:16px}.file-upload p{color:var(--text-secondary);margin-bottom:8px}.file-upload span{color:var(--primary);font-weight:500}.form-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}.books-list{display:grid;gap:12px}.book-item{display:flex;justify-content:space-between;align-items:center;padding:16px 20px;background:var(--background-light);border-radius:var(--radius-md);border:1px solid var(--border-light)}.book-info h3{font-size:15px;font-weight:600;color:var(--text-primary);margin-bottom:4px}.book-info p{font-size:13px;color:var(--text-muted)}.book-badges{display:flex;gap:8px}.book-badge{padding:4px 12px;background:#2754411a;color:var(--primary);border-radius:20px;font-size:12px;font-weight:500}@media (max-width: 1024px){.main-content{flex-direction:column;padding:24px}.form-panel{width:100%}}@media (max-width: 768px){.header{padding:0 20px;height:60px}.logo-text{font-size:18px}.user-name{display:none}.main-content{padding:20px;gap:20px}.form-panel,.output-panel{padding:20px}.panel-title{font-size:20px}.form-grid{grid-template-columns:1fr}.lesson-meta{flex-wrap:wrap;gap:16px}.teacher-resources-header{padding:16px}.teacher-resources-content{padding:0 16px 16px}.video-container{border-radius:0 0 6px 6px}}.auth-container{display:flex;min-height:100vh;width:100%}.auth-brand-panel{width:50%;background:var(--primary);display:flex;align-items:center;justify-content:center;padding:48px}.auth-brand-panel-narrow{width:40%}.auth-brand-content{display:flex;flex-direction:column;align-items:center;gap:24px;text-align:center}.auth-brand-icon{color:#fff}.auth-brand-icon svg{width:64px;height:64px}.auth-brand-title{font-size:36px;font-weight:600;color:#fff;margin:0}.auth-brand-subtitle{font-size:16px;font-weight:400;color:#fff;opacity:.8;max-width:400px;line-height:1.5;margin:0}.auth-form-panel{flex:1;background:var(--surface);display:flex;align-items:center;justify-content:center;padding:48px}.auth-form-container{width:100%;max-width:360px}.auth-form-container-wide{max-width:480px}.auth-form-header{margin-bottom:24px}.auth-form-title{font-size:28px;font-weight:600;color:var(--text-primary);margin:0 0 8px}.auth-form-subtitle{font-size:14px;font-weight:400;color:var(--text-secondary);margin:0}.auth-form{display:flex;flex-direction:column;gap:20px}.form-row{display:flex;gap:16px}.form-row .form-field{flex:1;margin-bottom:0}.password-input-wrapper{position:relative;display:flex;align-items:center}.password-input-wrapper .form-input{padding-right:48px}.password-toggle{position:absolute;right:16px;background:none;border:none;padding:0;cursor:pointer;color:var(--text-muted);display:flex;align-items:center;justify-content:center;transition:color .2s ease}.password-toggle:hover{color:var(--text-secondary)}.select-wrapper{position:relative}.auth-submit-btn{width:100%;height:48px;border:none;border-radius:var(--radius-md);background:var(--primary);color:#fff;font-size:16px;font-weight:600;cursor:pointer;display:flex;align-items:center;justify-content:center;gap:10px;transition:all .2s ease;margin-top:4px}.auth-submit-btn:hover:not(:disabled){background:var(--primary-dark);transform:translateY(-1px);box-shadow:0 4px 12px #2754414d}.auth-submit-btn:disabled{opacity:.6;cursor:not-allowed}.auth-submit-btn .spinner{border-color:#fff;border-top-color:transparent}.auth-switch-prompt{text-align:center;font-size:14px;color:var(--text-secondary)}.auth-switch-link{background:none;border:none;color:var(--primary);font-weight:600;cursor:pointer;padding:0;font-size:14px;transition:color .2s ease}.auth-switch-link:hover{color:var(--primary-dark);text-decoration:underline}@media (max-width: 1024px){.auth-brand-panel,.auth-brand-panel-narrow{width:45%}.auth-brand-title{font-size:28px}.auth-brand-subtitle{font-size:14px}}@media (max-width: 768px){.auth-container{flex-direction:column}.auth-brand-panel,.auth-brand-panel-narrow{width:100%;padding:40px 24px 32px}.auth-brand-icon svg{width:48px;height:48px}.auth-brand-title{font-size:22px}.auth-brand-subtitle{font-size:14px}.auth-brand-content{gap:16px}.auth-form-panel{padding:24px;border-radius:24px 24px 0 0;margin-top:-24px;position:relative;z-index:1}.auth-form-container,.auth-form-container-wide{max-width:100%}.auth-form-title{font-size:24px}.auth-form-header{margin-bottom:20px}.auth-form{gap:16px}.form-row{gap:12px}.form-field{margin-bottom:0}.form-label{font-size:13px;margin-bottom:6px}.form-input,.form-select{height:44px;font-size:13px}.auth-submit-btn{height:48px;font-size:15px}.auth-switch-prompt{font-size:13px}}