/* ========================================
   鹿途AI - 极简编辑风设计系统
   灵感来源: MONO阅读 / 屋颜App
   核心: 白底黑字 · 细线分隔 · 微圆角 · 无渐变无毛玻璃
   ======================================== */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent}
:root{
  --bg:#ffffff;--bg-elevated:#fafafa;
  --surface-1:#f8f8f8;--surface-2:#f2f2f2;--surface-3:#ebebeb;
  --border-subtle:#f0f0f0;--border-default:#e5e5e5;--border-strong:#d5d5d5;
  --primary:#111111;--primary-bright:#333333;--primary-dim:#000000;
  --primary-glow:rgba(0,0,0,0.04);--primary-glow-strong:rgba(0,0,0,0.08);
  --accent:#111111;--accent-glow:rgba(0,0,0,0.04);
  --success:#111111;--success-glow:rgba(0,0,0,0.04);
  --error:#c0392b;--error-glow:rgba(192,57,43,0.06);
  --info:#111111;--info-glow:rgba(0,0,0,0.04);
  --text-1:#111111;--text-2:#666666;--text-3:#999999;
  --radius:2px;--radius-md:2px;--radius-lg:2px;--radius-sm:2px;--radius-xs:2px;
  --border:#e5e5e5;--card:#ffffff;--card2:#fafafa;
  --gold:#111;--green:#111;--red:#c0392b;
  --text2:#666666;--text3:#999999;
}
html,body{height:100%;width:100%;background:var(--bg);
  font-family:-apple-system,BlinkMacSystemFont,'SF Pro Display','SF Pro Text','Segoe UI',Roboto,'PingFang SC','Microsoft YaHei','Noto Sans SC',sans-serif;
  color:var(--text-1);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;line-height:1.6;font-size:15px}
a{color:var(--text-1);text-decoration:none;border-bottom:1px solid var(--border-default);transition:border-color .2s}
a:hover{border-color:var(--text-1)}
input,select,textarea,button{font-family:inherit;font-size:inherit;border:none;outline:none}

/* === BACKGROUND (removed aurora, pure white) === */
.aurora-bg{display:none}

/* === LOGIN === */
.login-wrap{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px;min-height:100vh;background:#fff;position:relative}
.login-wrap::before,.login-wrap::after{display:none}
.login-slogan{position:relative;z-index:1;text-align:center;margin-bottom:40px;flex-shrink:0;width:auto}
.login-slogan h2{font-size:28px;font-weight:700;color:#111;letter-spacing:4px;background:none;-webkit-background-clip:unset;-webkit-text-fill-color:#111}
.login-slogan p{color:#999;font-size:13px;margin-top:10px;letter-spacing:2px;font-weight:400}
.slogan-vertical{display:flex;gap:20px;justify-content:center;margin-top:12px}
.slogan-vertical span{writing-mode:vertical-rl;text-orientation:upright;font-size:14px;color:#999;letter-spacing:6px;font-weight:300;line-height:1.4}
.login-box{
  background:#fff;border:1px solid var(--border-default);border-radius:2px;
  padding:40px 32px;width:100%;max-width:380px;
  box-shadow:0 1px 3px rgba(0,0,0,0.06);
  animation:fadeUp .4s ease}
@keyframes fadeUp{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}
.login-logo{text-align:center;margin-bottom:28px}
.login-logo h1{font-size:22px;font-weight:700;color:#111;letter-spacing:2px;background:none;-webkit-background-clip:unset;-webkit-text-fill-color:#111}
.login-logo p{color:#999;font-size:13px;margin-top:8px;letter-spacing:1px}
.input-group{position:relative;margin-bottom:16px}
.input-group input,.inp{width:100%;background:#fff;border:1px solid var(--border-default);
  border-radius:2px;padding:14px 16px;color:var(--text-1);font-size:14px;
  transition:border-color .2s}
.input-group input:focus,.inp:focus{border-color:#111;box-shadow:none}
.input-group input::placeholder,.inp::placeholder{color:#bbb}
.btn-primary,.btn{width:100%;
  background:#111;color:#fff;border:none;border-radius:2px;padding:14px;font-size:15px;
  cursor:pointer;font-weight:500;letter-spacing:1px;
  transition:opacity .2s;box-shadow:none}
.btn-primary:hover,.btn:hover{opacity:0.85}
.btn-primary:active,.btn:active{opacity:0.7}
.btn-sm{padding:8px 18px;font-size:13px;width:auto;border-radius:2px}
.btn-full{width:100%;padding:14px;font-size:15px}
.btn-green{background:#111;box-shadow:none}
.btn-red{background:#c0392b;box-shadow:none}
.btn-gold{background:#111;box-shadow:none}
.btn-outline{background:#fff;border:1px solid var(--border-default);color:var(--text-2);box-shadow:none}
.btn-outline:hover{border-color:#111;color:#111}
.err{color:var(--error);font-size:13px;text-align:center;margin-top:12px;display:none}

/* === APP LAYOUT === */
.app{display:none;height:100vh;flex-direction:column}

/* === BOTTOM NAV === */
.sidebar{
  background:#fff;border-top:1px solid var(--border-default);
  display:flex;flex-direction:row;flex-shrink:0;
  padding:0 0 env(safe-area-inset-bottom,0px);overflow-x:auto;-webkit-overflow-scrolling:touch}
.sidebar::-webkit-scrollbar{display:none}
.logo{display:none}
.nav{display:flex;flex-direction:row;gap:0;padding:0;width:100%;justify-content:space-around}
.nav-group{display:none}
.nav-item{display:flex;flex-direction:column;align-items:center;gap:4px;padding:12px 16px;
  cursor:pointer;color:#999;font-size:11px;font-weight:500;
  transition:color .2s;position:relative;min-width:64px;text-align:center;border-top:2px solid transparent}
.nav-item:hover{color:#666}
.nav-item:active{color:#111}
.nav-item.active{color:#111;background:transparent;border-top:2px solid #111;border-radius:0;box-shadow:none}
.nav-item svg{width:20px;height:20px;flex-shrink:0;opacity:0.6}
.nav-item.active svg{opacity:1;stroke:#111}
.nav-item span{display:block}
.user-info{display:none}

/* === TOP BAR === */
.topbar{
  background:#fff;border-bottom:1px solid var(--border-default);
  padding:14px 24px;display:flex;align-items:center;justify-content:space-between;flex-shrink:0}
.topbar-left{display:flex;align-items:center;gap:12px}
.topbar-left h2{font-size:15px;font-weight:600;color:#111;letter-spacing:1px;background:none;-webkit-background-clip:unset;-webkit-text-fill-color:#111}
.topbar-left span{font-size:12px;color:#999}
.topbar-right{display:flex;align-items:center;gap:12px;font-size:13px}
.topbar-right .user-name{color:#111;font-weight:500}
.topbar-right .logout-btn{color:#999;cursor:pointer;transition:color .2s}
.topbar-right .logout-btn:hover{color:#111}

/* === MAIN CONTENT === */
.main{flex:1;overflow-y:auto;padding:24px;-webkit-overflow-scrolling:touch;scroll-behavior:smooth;background:#fff}
.main::-webkit-scrollbar{width:4px}
.main::-webkit-scrollbar-track{background:transparent}
.main::-webkit-scrollbar-thumb{background:#ddd;border-radius:2px}
.page{display:none;animation:pageFadeIn .3s ease}
.page.active{display:block}
@keyframes pageFadeIn{from{opacity:0}to{opacity:1}}
.page-title{font-size:20px;font-weight:600;margin-bottom:24px;display:flex;align-items:center;gap:10px;
  color:#111;letter-spacing:0.5px}
.page-title .icon{width:32px;height:32px;border-radius:2px;
  background:var(--surface-1);
  display:flex;align-items:center;justify-content:center;font-size:16px}

/* === STATS CARDS === */
.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;margin-bottom:24px}
.stat-card{
  background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:20px 22px;
  transition:border-color .2s;position:relative;overflow:hidden}
.stat-card::before{display:none}
.stat-card:hover{border-color:#111}
.stat-card .label{color:#999;font-size:12px;margin-bottom:8px;font-weight:500;letter-spacing:0.5px}
.stat-card .value{font-size:28px;font-weight:700;color:#111;background:none;-webkit-background-clip:unset;-webkit-text-fill-color:#111}
.stat-card.purple .value,.stat-card.gold .value,.stat-card.green .value{background:none;-webkit-background-clip:unset;-webkit-text-fill-color:#111}

/* === TOOLBAR === */
.toolbar{display:flex;gap:10px;margin-bottom:18px;flex-wrap:wrap;align-items:center}

/* === TABLE === */
.tbl-wrap{
  background:#fff;border:1px solid var(--border-default);border-radius:2px;overflow:hidden;margin-bottom:18px}
table{width:100%;border-collapse:collapse}
th{background:var(--surface-1);padding:12px 16px;text-align:left;font-size:12px;
  color:#999;font-weight:500;border-bottom:1px solid var(--border-default);
  text-transform:uppercase;letter-spacing:0.5px}
td{padding:12px 16px;font-size:14px;border-bottom:1px solid var(--border-subtle);
  color:#111}
tr:last-child td{border-bottom:none}
tr{transition:background .15s}
tr:hover{background:var(--surface-1)}
tr:hover td:first-child{box-shadow:inset 3px 0 0 #111}

/* === BADGES === */
.badge{display:inline-flex;align-items:center;padding:3px 10px;border-radius:1px;
  font-size:11px;font-weight:500;letter-spacing:0.3px;border:1px solid var(--border-default)}
.badge-purple{background:var(--surface-1);color:#111;border-color:var(--border-strong)}
.badge-green{background:var(--surface-1);color:#111;border-color:var(--border-strong)}
.badge-gold{background:var(--surface-1);color:#111;border-color:var(--border-strong)}
.badge-red{background:var(--surface-1);color:var(--error);border-color:var(--error)}
.badge-blue{background:var(--surface-1);color:#111;border-color:var(--border-strong)}

/* === MODAL === */
.modal-bg{display:none;position:fixed;inset:0;background:rgba(0,0,0,0.3);z-index:100;
  align-items:center;justify-content:flex-end;padding-bottom:15vh}
.modal-bg.show{display:flex}
.modal{
  background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:28px;
  width:540px;max-width:92vw;max-height:85vh;overflow-y:auto;
  box-shadow:0 8px 32px rgba(0,0,0,0.1);animation:modalFadeIn .2s ease}
@keyframes modalFadeIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}
.modal h3{font-size:18px;margin-bottom:20px;font-weight:600;color:#111}
.form-group{margin-bottom:16px}
.form-group label{display:block;font-size:12px;color:#999;margin-bottom:6px;font-weight:500;letter-spacing:0.5px}
.form-group input,.form-group select,.form-group textarea{width:100%;background:#fff;
  border:1px solid var(--border-default);border-radius:2px;padding:10px 14px;
  color:#111;font-size:14px;transition:border-color .2s}
.form-group input:focus,.form-group select:focus,.form-group textarea:focus{
  border-color:#111;box-shadow:none}
.btn-row{display:flex;gap:10px;justify-content:flex-end;margin-top:20px}
.btn-cancel{background:#fff;color:#666;border:1px solid var(--border-default);
  border-radius:2px;padding:8px 20px;cursor:pointer;font-size:13px;font-weight:500;
  transition:border-color .2s}
.btn-cancel:hover{border-color:#111;color:#111}

/* === TOAST === */
.toast{position:fixed;top:24px;right:24px;
  background:#fff;border:1px solid var(--border-default);border-radius:2px;
  padding:14px 20px;font-size:14px;color:#111;z-index:2000;
  transform:translateX(120%);transition:transform .3s ease;
  box-shadow:0 4px 16px rgba(0,0,0,0.08)}
.toast.show{transform:translateX(0)}
.toast.success{border-color:#111}
.toast.error{border-color:var(--error)}

/* === UPLOAD AREA === */
.upload-zone{border:1px dashed var(--border-strong);border-radius:2px;padding:32px;
  text-align:center;cursor:pointer;transition:border-color .2s;margin-bottom:18px;
  background:#fff}
.upload-zone:hover{border-color:#111}
.upload-zone p{color:#999;margin-top:10px;font-size:13px}
.upload-zone .icon{font-size:32px;margin-bottom:8px;color:#999}
.file-tag{display:inline-flex;align-items:center;gap:6px;background:var(--surface-1);
  border:1px solid var(--border-default);border-radius:2px;padding:6px 12px;
  font-size:12px;margin:4px}
.file-tag .remove{color:var(--error);cursor:pointer;font-weight:700}
.progress-bar{height:4px;background:var(--surface-2);border-radius:2px;margin-top:10px;overflow:hidden}
.progress-bar .fill{height:100%;background:#111;border-radius:2px;transition:width .3s}

/* === COURSE GRID === */
.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:14px}
.course-card{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:22px;cursor:pointer;transition:border-color .2s;position:relative}
.course-card:hover{border-color:#111}
.course-card .stage{font-size:11px;color:#999;margin-bottom:6px;font-weight:500;letter-spacing:0.5px;text-transform:uppercase}
.course-card .title{font-size:16px;font-weight:600;margin-bottom:8px;line-height:1.4;color:#111}
.course-card .desc{font-size:13px;color:#666;margin-bottom:12px;line-height:1.6;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.course-card .meta{display:flex;gap:12px;font-size:12px;color:#999}

/* === DETAIL === */
.detail-header{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:24px;margin-bottom:20px}
.detail-header h2{font-size:20px;margin-bottom:8px;font-weight:600;color:#111}
.detail-header .info{color:#666;font-size:14px;line-height:1.7}

/* === FILE SECTION === */
.file-section{margin-bottom:20px}
.file-section-title{font-size:16px;font-weight:600;margin-bottom:12px;display:flex;align-items:center;gap:8px;color:#111}
.file-section-title .icon{width:32px;height:32px;border-radius:2px;display:flex;align-items:center;justify-content:center;font-size:16px;background:var(--surface-1)}
.file-list-card{background:#fff;border:1px solid var(--border-default);border-radius:2px;overflow:hidden}
.file-item{display:flex;align-items:center;gap:12px;padding:12px 14px;transition:background .15s;cursor:pointer;border-bottom:1px solid var(--border-subtle)}
.file-item:last-child{border-bottom:none}
.file-item:hover{background:var(--surface-1)}
.file-icon{width:36px;height:36px;border-radius:2px;display:flex;align-items:center;justify-content:center;font-size:10px;font-weight:700;flex-shrink:0;border:1px solid var(--border-default)}
.file-icon.docx{background:var(--surface-1);color:#111}
.file-icon.pptx,.file-icon.ppt{background:var(--surface-1);color:#111}
.file-icon.pdf{background:var(--surface-1);color:#111}
.file-icon.other{background:var(--surface-1);color:#111}
.file-info{flex:1;min-width:0}
.file-name{font-size:14px;font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:#111}
.file-size{font-size:12px;color:#999;margin-top:2px}
.file-actions{display:flex;gap:8px;margin-left:auto;flex-shrink:0}
.present-btn{background:#111;color:#fff;border:none;border-radius:2px;padding:8px 16px;font-size:12px;cursor:pointer;display:flex;align-items:center;gap:5px;transition:opacity .2s;font-weight:500}
.present-btn:hover{opacity:0.85}
.present-btn:active{opacity:0.7}
.present-btn svg{width:14px;height:14px}
.no-course-hint{background:var(--surface-1);border:1px solid var(--border-default);border-radius:2px;padding:14px 18px;margin-bottom:18px;color:#666;font-size:13px;line-height:1.6}

/* === TRAINING OVERLAY === */
.training-overlay{display:none;position:fixed;inset:0;z-index:2000;background:#fff;flex-direction:column;overflow-y:auto}
.training-overlay.active{display:flex}
.training-header{background:#fff;border-bottom:1px solid var(--border-default);padding:20px 24px;position:sticky;top:0;z-index:10}
.training-header h2{font-size:18px;font-weight:600;color:#111}
.training-header p{font-size:13px;color:#999}
.training-progress{margin-top:12px;height:4px;background:var(--surface-2);border-radius:2px;overflow:hidden}
.training-progress-fill{height:100%;background:#111;border-radius:2px;transition:width .3s}
.training-body{flex:1;padding:24px;max-width:800px;margin:0 auto;width:100%}
.training-material{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:28px;margin-bottom:20px}
.training-material h3{font-size:20px;font-weight:600;margin-bottom:16px;color:#111}
.training-material .content{line-height:1.9;color:#444;font-size:15px}
.training-material .content h2{font-size:17px;font-weight:600;color:#111;margin:20px 0 10px}
.training-material .content h3{font-size:15px;font-weight:600;color:#111;margin:16px 0 8px}
.training-material .content p{margin:10px 0}
.training-material .content ul,.training-material .content ol{margin:10px 0;padding-left:24px}
.training-material .content li{margin:6px 0}
.training-material .content strong{color:#111}
.training-nav{display:flex;gap:10px;justify-content:center;margin-top:20px;padding-bottom:40px}
.training-nav .btn{min-width:120px}

/* === PASSWORD CHANGE === */
.pwd-change-overlay{display:none;position:fixed;inset:0;z-index:3000;background:rgba(0,0,0,0.3);align-items:center;justify-content:center}
.pwd-change-overlay.active{display:flex}
.pwd-change-box{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:32px;max-width:400px;width:90%;text-align:center}
.pwd-change-box h2{font-size:18px;font-weight:600;margin-bottom:8px;color:#111}
.pwd-change-box p{font-size:13px;color:#999;margin-bottom:20px}
.pwd-change-box .form-group{text-align:left;margin-bottom:14px}
.pwd-change-box .form-group label{display:block;font-size:12px;color:#999;margin-bottom:4px}
.pwd-change-box .form-group input{width:100%;background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:10px 12px;color:#111;font-size:14px}
.pwd-change-box .err{color:var(--error);font-size:13px;margin-top:8px;display:none}

/* === EXAM === */
.exam-overlay{display:none;position:fixed;inset:0;z-index:2000;background:#fff;flex-direction:column;overflow-y:auto}
.exam-overlay.active{display:flex}
.exam-header{background:#fff;border-bottom:1px solid var(--border-default);padding:20px 24px;position:sticky;top:0;z-index:10;display:flex;align-items:center;justify-content:space-between}
.exam-header h2{font-size:18px;font-weight:600;color:#111}
.exam-timer{font-size:14px;color:#111;font-weight:600}
.exam-body{flex:1;padding:24px;max-width:800px;margin:0 auto;width:100%}
.exam-question{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:22px;margin-bottom:16px}
.exam-question .q-num{font-size:12px;color:#999;font-weight:500;margin-bottom:6px}
.exam-question .q-text{font-size:15px;font-weight:600;margin-bottom:14px;line-height:1.5;color:#111}
.exam-question .q-type{font-size:11px;color:#999;margin-bottom:6px}
.exam-options{display:flex;flex-direction:column;gap:8px}
.exam-option{display:flex;align-items:center;gap:10px;padding:12px 14px;background:#fff;border:1px solid var(--border-default);border-radius:2px;cursor:pointer;transition:border-color .2s}
.exam-option:hover{border-color:#111}
.exam-option.selected{border-color:#111;background:var(--surface-1)}
.exam-option .opt-label{width:26px;height:26px;border-radius:50%;background:var(--surface-1);border:1px solid var(--border-default);display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:600;color:#666;flex-shrink:0;transition:all .2s}
.exam-option.selected .opt-label{background:#111;border-color:#111;color:#fff}
.exam-option .opt-text{font-size:14px;color:#111}
.exam-result{display:none;position:fixed;inset:0;z-index:2500;background:rgba(0,0,0,0.3);align-items:center;justify-content:center}
.exam-result.active{display:flex}
.exam-result-box{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:40px 32px;max-width:420px;width:90%;text-align:center}
.exam-result-box .score{font-size:56px;font-weight:800;margin:16px 0;color:#111}
.exam-result-box .score.pass{color:#111}
.exam-result-box .score.fail{color:var(--error)}
.exam-result-box h3{font-size:18px;font-weight:600;margin-bottom:8px;color:#111}
.exam-result-box p{font-size:14px;color:#666;margin-bottom:20px;line-height:1.6}
.exam-result-box .btns{display:flex;gap:10px;justify-content:center}

/* === PRESENTER (Teacher) === */
.presenter{display:none;position:fixed;inset:0;z-index:1000;background:#000;flex-direction:column}
.presenter.active{display:flex}
.presenter-main{flex:1;display:flex;align-items:center;justify-content:center;position:relative;overflow:hidden}
.presenter-main img{max-width:90%;max-height:85%;object-fit:contain;border-radius:2px}
.presenter-controls{background:#fff;border-top:1px solid var(--border-default);padding:14px 24px;display:flex;align-items:center;gap:14px}
.presenter-title{font-size:14px;font-weight:500;color:#111;flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.presenter-nav{display:flex;align-items:center;gap:10px}
.presenter-nav button{width:36px;height:36px;border-radius:50%;background:#fff;border:1px solid var(--border-default);color:#111;cursor:pointer;transition:border-color .2s;display:flex;align-items:center;justify-content:center;font-size:16px}
.presenter-nav button:hover{border-color:#111}
.presenter-nav button:active{background:var(--surface-1)}
.presenter-page{font-size:13px;color:#999;min-width:50px;text-align:center}
.progress-bar{flex:1;height:3px;background:var(--surface-2);border-radius:2px;cursor:pointer;position:relative}
.progress-fill{height:100%;background:#111;border-radius:2px;transition:width .2s;position:relative}
.progress-fill::after{content:'';position:absolute;right:-5px;top:-3px;width:9px;height:9px;border-radius:50%;background:#111}
.thumb-strip{display:flex;gap:6px;overflow-x:auto;padding:10px 24px;background:#fff;border-top:1px solid var(--border-default)}
.thumb-strip::-webkit-scrollbar{height:3px}
.thumb-strip::-webkit-scrollbar-thumb{background:#ddd;border-radius:2px}
.thumb-item{width:72px;height:45px;border-radius:2px;overflow:hidden;cursor:pointer;border:2px solid transparent;transition:all .2s;flex-shrink:0;opacity:0.5}
.thumb-item:hover{opacity:0.8}
.thumb-item.active{border-color:#111;opacity:1}
.thumb-item img{width:100%;height:100%;object-fit:cover}
.presenter-loading{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;background:rgba(0,0,0,0.8);z-index:10}
.presenter-loading .spinner{width:36px;height:36px;border:2px solid var(--surface-2);border-top-color:#111;border-radius:50%;animation:spin 1s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.presenter-loading p{color:#999;margin-top:14px;font-size:14px}

/* === DOC VIEWER === */
.doc-viewer{display:none;position:fixed;inset:0;z-index:900;background:#fff;flex-direction:column}
.doc-viewer.active{display:flex}
.doc-viewer-header{background:#fff;border-bottom:1px solid var(--border-default);padding:14px 24px;display:flex;align-items:center;gap:14px}
.doc-viewer-header h3{flex:1;font-size:15px;font-weight:600;color:#111}
.doc-viewer-close{width:32px;height:32px;border-radius:50%;background:#fff;border:1px solid var(--border-default);color:#111;cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:16px;transition:border-color .2s}
.doc-viewer-close:hover{border-color:#111}
.doc-viewer-body{flex:1;overflow-y:auto;padding:28px;max-width:900px;margin:0 auto;width:100%}
.doc-viewer-body h1,.doc-viewer-body h2,.doc-viewer-body h3{margin:20px 0 10px;color:#111}
.doc-viewer-body p{margin:10px 0;line-height:1.8;color:#444}
.note-area{background:#fff;border:1px solid var(--border-default);border-radius:2px;padding:16px;color:#111;font-size:14px;min-height:200px;width:100%;resize:vertical;transition:border-color .2s}
.note-area:focus{border-color:#111;box-shadow:none}

/* === WATERMARK === */
.watermark{position:fixed;top:50%;left:50%;transform:translate(-50%,-50%) rotate(-45deg);font-size:48px;color:rgba(0,0,0,0.03);pointer-events:none;z-index:9999;white-space:nowrap;font-weight:700;letter-spacing:8px;user-select:none}

/* === Splash (disabled) === */
.splash-screen{display:none !important}

/* === RESPONSIVE === */
@media(max-width:768px){
  .nav-item{padding:10px 10px;font-size:10px;min-width:56px}
  .nav-item svg{width:18px;height:18px}
  .main{padding:16px}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .modal{padding:20px}
  .course-grid{grid-template-columns:1fr}
  .course-card{padding:16px}
  .training-body,.exam-body{padding:16px}
  .training-material{padding:18px}
  .exam-question{padding:16px}
  .pwd-change-box{padding:24px 18px}
}
@media(max-width:400px){
  .course-card .title{font-size:15px}
  .training-material .content{font-size:14px}
  .exam-question .q-text{font-size:14px}
}

/* === EDITORIAL DETAILS === */
/* 登录页竖线装饰 */
.login-title-bar{display:inline-block;width:3px;height:28px;background:#111;margin-right:10px;vertical-align:middle;border-radius:1px}
.login-slogan .en-subtitle{font-size:11px;color:#ccc;letter-spacing:6px;text-transform:uppercase;margin-top:6px;font-weight:300}

/* Topbar竖线 */
.topbar-bar{display:inline-block;width:2px;height:14px;background:#111;margin-right:8px;vertical-align:middle;border-radius:1px}

/* 页面标题英文标注 */
.page-title-wrap{margin-bottom:24px}
.page-title-wrap .page-en{font-size:11px;color:#ccc;letter-spacing:4px;text-transform:uppercase;font-weight:400;margin-bottom:2px}
.page-title-wrap .page-title{margin-bottom:0}

/* 卡片编号 */
.stat-card .card-num{position:absolute;top:8px;right:10px;font-size:10px;color:#ddd;font-weight:600;letter-spacing:1px}

/* 底部版本 */
.page-footer{text-align:center;padding:24px 0 12px;font-size:10px;color:#ddd;letter-spacing:2px}