:root{
  --bg:#F5F4F3;
  --surface:#FFFFFF;
  --surface2:#EFEEEC;
  --ink:#23201E;
  --ink2:#625B57;
  --ink3:#A09A96;
  --line:#EBEBE9;
  --line2:#DFDFDD;
  --accent:#4E1717;
  --accent-ink:#4E1717;
  --accent-deep:#3A0F0F;
  --accent-soft:#EDE3E1;
  --accent-line:rgba(78,23,23,.28);
  --green:#174C38;
  --green-soft:#DFEBE6;
  --red:#C6453C;
  --red-soft:rgba(198,69,60,.1);
  --shadow:0 1px 2px rgba(35,32,30,.04),0 10px 28px -14px rgba(35,32,30,.10);
  --radius:18px;
  --sans:'Pretendard Variable',Pretendard,-apple-system,'Apple SD Gothic Neo','Noto Sans KR',sans-serif;
  --serif:'Noto Serif KR','Noto Serif CJK KR','Apple SD Gothic Neo',ui-serif,serif;
}

*{box-sizing:border-box}
html{min-height:100%;background:var(--bg);scroll-behavior:smooth}
body{min-height:100vh;margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:15px;line-height:1.5;word-break:keep-all;-webkit-font-smoothing:antialiased}
button,input,select{font:inherit}
button{color:inherit}
[hidden]{display:none!important}
.ambient{display:none}
.site-shell{width:min(960px,calc(100% - 36px));margin:0 auto;padding:0 0 52px}

.brand{display:inline-flex;align-items:center;gap:11px;color:inherit;text-decoration:none}
.brand-mark{display:grid;place-items:center;width:42px;height:42px;flex:none;border-radius:14px;background:var(--ink);color:var(--bg);box-shadow:var(--shadow)}
.brand-mark span{font:900 17px/1 var(--serif)}
.brand-copy{display:flex;flex-direction:column;line-height:1}
.brand-copy b{font:900 18px/1 var(--serif);letter-spacing:.12em}
.brand-copy small{margin-top:5px;color:var(--ink3);font-size:8px;font-weight:800;letter-spacing:.18em}

.loading-view,.error-view{width:min(520px,100%);min-height:100vh;margin:auto;padding:30px 18px;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center}
.loading-brand{width:58px;height:58px;border-radius:18px}
.loading-brand span{font-size:23px}
.eyebrow{margin:20px 0 8px;color:var(--accent-ink);font-size:10.5px;font-weight:800;letter-spacing:.16em;text-transform:uppercase}
.loading-view h1,.error-view h1{margin:0;font:800 clamp(24px,5vw,34px)/1.4 var(--serif);letter-spacing:-.02em}
.loading-view .subtle{max-width:380px;margin:14px 0 0;color:var(--ink3);font-size:13px}
.loading-line{width:210px;height:4px;margin-top:24px;overflow:hidden;border-radius:999px;background:var(--surface2)}
.loading-line i{display:block;width:42%;height:100%;border-radius:inherit;background:var(--accent);animation:loading 1.35s ease-in-out infinite}
@keyframes loading{0%{transform:translateX(-120%)}100%{transform:translateX(360%)}}
.error-icon{display:grid;place-items:center;width:58px;height:58px;border-radius:18px;background:var(--red-soft);color:var(--red)}
.error-icon svg{width:29px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round}
.error-view>p:not(.eyebrow){max-width:420px;margin:12px 0 22px;color:var(--ink2);font-size:13px}

.report-header{position:sticky;top:0;z-index:20;display:flex;align-items:center;justify-content:space-between;gap:12px;margin:0 -2px 14px;padding:14px 2px 12px;background:var(--bg);border-bottom:1px solid var(--line)}
.header-actions{display:flex;align-items:center}
.live-dot{width:7px;height:7px;border-radius:50%;background:var(--green)}
.refresh-button{display:grid;place-items:center;width:38px;height:38px;padding:0;border:1px solid var(--line);border-radius:12px;background:var(--surface);cursor:pointer;box-shadow:var(--shadow);transition:transform .12s,color .15s}
.refresh-button:active{transform:scale(.94)}
.refresh-button:hover{color:var(--accent-ink)}
.refresh-button svg{width:18px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.refresh-button.loading svg{animation:spin .8s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}

.hero-card{display:block;overflow:hidden;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow)}
.hero-copy{padding:25px 27px 26px;text-align:center}
.hero-kicker{margin:0 0 7px;color:var(--ink3);font-size:10.5px;font-weight:800;letter-spacing:.16em;text-transform:uppercase}
.hero-copy h1{margin:0;font:900 clamp(27px,4vw,36px)/1.35 var(--serif);letter-spacing:-.025em}
.hero-copy h1 br{display:none}
.hero-copy h1 em{color:var(--accent-ink);font-style:normal}
.hero-description{max-width:650px;margin:12px auto 0;color:var(--ink2);font-size:13.5px;line-height:1.7}
.hero-meta{display:flex;justify-content:center;flex-wrap:wrap;gap:7px;margin-top:18px}
.hero-meta span{padding:5px 9px;border-radius:999px;background:var(--accent-soft);color:var(--accent-ink);font-size:10.5px;font-weight:800}

.stat-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin:10px 0 28px}
.stat-card{display:flex;min-height:86px;padding:14px 16px;align-items:center;justify-content:center;border:1px solid var(--line);border-radius:16px;background:var(--surface);text-align:center;box-shadow:var(--shadow)}
.stat-icon{display:none}
.stat-card div{display:block}
.stat-card small{display:block;margin-bottom:6px;color:var(--ink2);font-size:11px;font-weight:700}
.stat-card strong{font:800 23px/1.2 var(--serif)}
.stat-card strong:after{content:"회";margin-left:3px;color:var(--ink3);font:700 11px/1 var(--sans)}
.stat-card:nth-child(2) strong:after,.stat-card:nth-child(3) strong:after{content:"곡"}

.content-grid{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:22px;align-items:start}
.main-column{min-width:0}
.content-section{margin-bottom:26px}
.section-heading{display:flex;align-items:baseline;justify-content:space-between;gap:10px;margin:0 2px 12px}
.section-kicker{margin:0 0 3px;color:var(--ink3);font-size:10.5px;font-weight:800;letter-spacing:.16em;text-transform:uppercase}
.section-heading h2{margin:0;font-family:var(--sans);font-size:18px;font-weight:800;letter-spacing:-.015em}
.section-actions{display:flex;flex-direction:column;align-items:flex-end;gap:4px}
.section-link-button{padding:6px 9px;border:1px solid var(--accent-line);border-radius:10px;background:var(--surface);color:var(--accent-ink);font-size:10.5px;font-weight:800;cursor:pointer;box-shadow:var(--shadow)}
.section-link-button:active{transform:scale(.97)}
.section-link-button span{margin-left:2px}
.sync-time{color:var(--ink3);font-size:10.5px;font-weight:700}
.timeline{position:relative;padding:3px 18px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow)}
.timeline:before{content:"";position:absolute;left:22px;top:27px;bottom:27px;width:1px;background:var(--line2)}
.lesson-card{position:relative;display:grid;grid-template-columns:10px minmax(0,1fr);gap:14px;border-top:1px solid var(--line)}
.lesson-card:first-child{border-top:0}
.timeline-marker{position:relative;z-index:1;width:9px;height:9px;margin-top:26px;border-radius:50%;background:var(--line2)}
.lesson-card:first-child .timeline-marker{background:var(--accent);box-shadow:0 0 0 4px var(--accent-soft)}
.lesson-body{padding:17px 0 18px}
.lesson-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px}
.lesson-date{margin:0;font:800 16px/1.35 var(--serif);letter-spacing:-.015em}
.lesson-meta{margin:4px 0 0;color:var(--ink3);font-size:11px;font-weight:700}
.song-tag{max-width:45%;padding:4px 8px;overflow:hidden;border-radius:999px;background:var(--accent-soft);color:var(--accent-ink);font-size:10px;font-weight:800;text-overflow:ellipsis;white-space:nowrap}
.lesson-content{margin-top:13px}
.lesson-content>span,.feedback-box>span{display:block;margin-bottom:5px;color:var(--ink3);font-size:10px;font-weight:800}
.lesson-content p,.feedback-box p{margin:0;font-size:13.5px;line-height:1.65;white-space:pre-line}
.feedback-box{margin-top:11px;padding:11px 13px;border-radius:10px;background:var(--surface2)}
.feedback-box>span{color:var(--accent-ink)}
.feedback-box p{color:var(--ink2);font-size:12.5px}
.empty-card{padding:34px 20px;border:1px dashed var(--line2);border-radius:var(--radius);text-align:center;background:var(--surface)}
.empty-card span{display:block;color:var(--accent-ink);font:700 27px/1 var(--serif)}
.empty-card b{display:block;margin-top:10px;font-size:15px}
.empty-card p{margin:6px 0 0;color:var(--ink3);font-size:12px}

.side-column{position:sticky;top:82px;display:grid;gap:14px}
.side-card{padding:18px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow)}
.side-heading{display:flex;align-items:center;gap:8px;margin-bottom:13px}
.side-heading p{margin:0;flex:1;font-size:14px;font-weight:800}
.side-heading b{display:grid;place-items:center;min-width:25px;height:25px;padding:0 7px;border-radius:999px;background:var(--accent-soft);color:var(--accent-ink);font-size:10px}
.side-icon{display:grid;place-items:center;width:22px;height:22px;border-radius:8px;background:var(--surface2);color:var(--accent-ink);font-weight:900}
.current-song{padding:12px 0;border-top:1px solid var(--line)}
.current-song:first-child{padding-top:1px;border-top:0}
.current-song p{margin:0;font-family:var(--serif);font-size:17px;font-weight:800;line-height:1.45}
.current-song small{display:block;margin-top:3px;color:var(--ink3);font-size:10.5px;font-weight:650}
.current-empty{margin:0;color:var(--ink3);font-size:12px;line-height:1.65}
.side-helper{margin:-5px 0 13px;color:var(--ink3);font-size:10.5px;line-height:1.55}
.skill-list{display:grid;grid-template-columns:repeat(5,1fr);gap:5px}
.skill-cell{min-width:0;padding:10px 1px 9px;border-radius:13px;background:var(--surface2);text-align:center}
.skill-name{display:block;color:var(--ink2);font-size:clamp(8px,1.7vw,10px);font-weight:750;letter-spacing:-.04em;white-space:nowrap}
.skill-level{display:block;margin-top:6px;color:var(--accent-ink);font:800 20px/1 var(--serif)}
.learned-list{display:grid}
.learned-song{display:grid;grid-template-columns:26px minmax(0,1fr);gap:9px;padding:10px 0;border-top:1px solid var(--line)}
.learned-song:first-child{padding-top:0;border-top:0}
.learned-song:nth-child(n+7){display:none}
.learned-list.expanded .learned-song:nth-child(n+7){display:grid}
.learned-song>span{display:grid;place-items:center;width:26px;height:26px;border-radius:9px;background:var(--surface2);color:var(--ink3);font:800 10px/1 var(--serif)}
.learned-song p{margin:0;font-size:12px;font-weight:700;line-height:1.45}
.learned-song small{display:block;margin-top:2px;color:var(--ink3);font-size:9.5px;font-weight:600}
.text-button{width:100%;margin-top:9px;padding:9px;border:0;border-radius:12px;background:var(--surface2);color:var(--accent-ink);font-size:11px;font-weight:800;cursor:pointer}
.text-button:active{transform:scale(.98)}

.all-lessons-view{padding-top:5px}
.back-button{display:inline-flex;align-items:center;gap:6px;margin:2px 0 24px;padding:8px 11px;border:1px solid var(--line);border-radius:11px;background:var(--surface);font-size:11px;font-weight:800;cursor:pointer;box-shadow:var(--shadow)}
.back-button:active{transform:scale(.97)}
.all-lessons-heading{margin-bottom:18px;text-align:center}
.all-lessons-heading .section-kicker{margin-bottom:5px}
.all-lessons-heading h1{margin:0;font:900 clamp(27px,4vw,36px)/1.35 var(--serif);letter-spacing:-.025em}
.all-lessons-heading>p:last-child{max-width:520px;margin:9px auto 0;color:var(--ink2);font-size:12.5px}
.calendar-card,.calendar-detail{width:min(680px,100%);margin:0 auto;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow)}
.calendar-card{padding:20px}
.calendar-head{display:grid;grid-template-columns:38px 1fr 38px;align-items:center;gap:12px;margin-bottom:17px;text-align:center}
.calendar-head p{margin:0 0 2px;color:var(--ink3);font-size:9.5px;font-weight:800;letter-spacing:.12em}
.calendar-head h2{margin:0;font:800 19px/1.4 var(--serif)}
.calendar-nav{display:grid;place-items:center;width:38px;height:38px;padding:0;border:1px solid var(--line);border-radius:12px;background:var(--surface);font-size:16px;font-weight:700;cursor:pointer;box-shadow:var(--shadow)}
.calendar-nav:active:not(:disabled){transform:scale(.95)}
.calendar-nav:disabled{color:var(--ink3);background:var(--surface2);cursor:default;opacity:.45;box-shadow:none}
.calendar-weekdays,.calendar-grid{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));gap:5px}
.calendar-weekdays{margin-bottom:5px;color:var(--ink3);font-size:9.5px;font-weight:800;text-align:center}
.calendar-weekdays span{padding:4px 0}
.calendar-day{display:flex;aspect-ratio:1;min-width:0;padding:6px 2px;align-items:center;justify-content:flex-start;flex-direction:column;border:0;border-radius:12px;background:transparent;color:var(--ink2)}
button.calendar-day{font:inherit;cursor:pointer}
.calendar-day:nth-child(7n+1) .calendar-day-number{color:var(--red)}
.calendar-day-empty{visibility:hidden}
.calendar-day-number{font-size:11px;font-weight:750;line-height:1.2}
.calendar-day.has-lesson{background:var(--accent-soft);color:var(--accent-ink)}
.calendar-day.has-lesson:hover{box-shadow:inset 0 0 0 1px var(--accent-line)}
.calendar-day.has-lesson.selected{background:var(--accent);color:#fff;box-shadow:0 7px 14px -9px var(--accent)}
.calendar-day.has-lesson.selected .calendar-day-number{color:#fff}
.calendar-lesson-mark{margin-top:auto;font-size:8px;font-weight:850;line-height:1}
.calendar-legend{display:flex;margin:14px 0 0;align-items:center;justify-content:center;gap:6px;color:var(--ink3);font-size:9.5px}
.calendar-legend i{width:8px;height:8px;border-radius:3px;background:var(--accent-soft);box-shadow:inset 0 0 0 1px var(--accent-line)}
.calendar-detail{margin-top:14px;overflow:hidden}
.calendar-detail-heading{padding:17px 20px 13px;border-bottom:1px solid var(--line)}
.calendar-detail-heading p{margin:0;color:var(--accent-ink);font-size:9.5px;font-weight:850;letter-spacing:.08em}
.calendar-detail-heading h2{margin:4px 0 0;font:800 18px/1.4 var(--serif)}
.calendar-detail-list{padding:0 20px}
.calendar-lesson-card{display:block;padding:0;border-top:1px solid var(--line)}
.calendar-lesson-card:first-child{border-top:0}
.calendar-lesson-card .lesson-body{padding:17px 0 19px}
.calendar-detail-empty{margin:0;padding:24px 20px;text-align:center;color:var(--ink3);font-size:12px}

.report-footer{padding:28px 4px 0;text-align:center;color:var(--ink3)}
.footer-rule{width:30px;height:1px;margin:0 auto 14px;background:var(--accent)}
.report-footer p{margin:0;font-size:11px}
.report-footer p b{font-family:var(--serif);letter-spacing:.12em;color:var(--ink2)}
.report-footer small{display:block;margin-top:5px;font-size:9.5px}

.primary-button{border:1px solid transparent;border-radius:14px;background:var(--accent);color:#fff;font-weight:700;box-shadow:0 8px 18px -8px var(--accent-line);cursor:pointer;transition:transform .12s,opacity .15s}
.primary-button:active{transform:scale(.98)}
.primary-button.compact{padding:11px 18px;font-size:12px}

.manage-shell{width:min(680px,calc(100% - 36px));margin:0 auto;padding:34px 0 64px}
.manage-header{display:flex;justify-content:center;margin-bottom:24px}
.manage-hero{text-align:center;margin-bottom:22px}
.manage-hero .eyebrow{margin-top:0}
.manage-hero h1{margin:0;font:900 clamp(27px,5vw,38px)/1.35 var(--serif);letter-spacing:-.025em}
.manage-hero p:last-child{margin:10px auto 0;color:var(--ink2);font-size:13px}
.manage-card{padding:26px;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow)}
.manage-notice{display:flex;gap:10px;margin-bottom:21px;padding:12px 13px;border-radius:13px;background:var(--accent-soft);color:var(--accent-ink);font-size:11px;line-height:1.55}
.manage-notice b{flex:none}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:15px}
.form-field{display:grid;gap:7px}
.form-field.full{grid-column:1/-1}
.form-field label{font-size:11px;font-weight:800}
.form-field input,.form-field select{width:100%;height:48px;padding:0 14px;border:1px solid var(--line2);border-radius:13px;outline:none;background:var(--surface);color:var(--ink);font-size:14px;transition:border-color .15s}
.form-field input:focus,.form-field select:focus{border-color:var(--accent)}
.form-hint{color:var(--ink3);font-size:9.5px}
.manage-submit{width:100%;height:50px;margin-top:20px}
.manage-error{min-height:19px;margin:10px 0 -3px;color:var(--red);font-size:11px;font-weight:700;text-align:center}
.share-result{margin-top:18px;padding:19px;border:1px solid rgba(23,76,56,.18);border-radius:16px;background:var(--green-soft)}
.share-result-head{display:flex;align-items:center;justify-content:space-between;gap:10px}
.share-result-head div{min-width:0}
.share-result-head p{margin:0;color:var(--green);font-size:10px;font-weight:800}
.share-result-head h2{margin:4px 0 0;font:800 19px/1.4 var(--serif)}
.share-result-head small{color:var(--ink2);font-size:9.5px}
.share-link{display:flex;gap:8px;margin-top:14px}
.share-link input{min-width:0;flex:1;height:44px;padding:0 12px;border:1px solid rgba(23,76,56,.18);border-radius:11px;background:var(--surface);color:var(--ink2);font-size:11px}
.share-link button{flex:none;padding:0 15px;border:0;border-radius:11px;background:var(--green);color:#fff;font-size:11px;font-weight:800;cursor:pointer}
.share-actions{display:flex;justify-content:flex-end;margin-top:11px}
.danger-link{padding:5px;border:0;background:none;color:var(--red);font-size:10px;font-weight:750;cursor:pointer}
.manage-foot{margin:15px 0 0;color:var(--ink3);font-size:10px;line-height:1.6;text-align:center}

@media(max-width:840px){
  .site-shell{width:min(700px,calc(100% - 30px))}
  .content-grid{grid-template-columns:1fr}
  .side-column{position:static;grid-template-columns:repeat(2,1fr)}
  .learned-card{grid-column:1/-1}
}

@media(max-width:560px){
  .site-shell{width:100%;padding:0 14px 38px}
  .report-header{padding-top:10px}
  .brand-mark{width:38px;height:38px;border-radius:12px}
  .brand-copy b{font-size:16px}
  .refresh-button{width:36px;height:36px}
  .hero-copy{padding:21px 19px 22px}
  .hero-copy h1{font-size:27px}
  .hero-description{font-size:12.5px}
  .stat-grid{grid-template-columns:1fr 1fr;margin-bottom:24px}
  .stat-card{min-height:78px;padding:13px 14px}
  .stat-card:last-child{grid-column:1/-1}
  .section-heading{align-items:flex-start}
  .section-link-button{white-space:nowrap}
  .sync-time{max-width:84px;margin-top:2px;text-align:right}
  .all-lessons-heading{padding:0 12px}
  .calendar-card{padding:16px 12px}
  .calendar-head{grid-template-columns:36px 1fr 36px;gap:8px}
  .calendar-nav{width:36px;height:36px}
  .calendar-weekdays,.calendar-grid{gap:3px}
  .calendar-day{padding:5px 1px;border-radius:10px}
  .calendar-day-number{font-size:10.5px}
  .calendar-lesson-mark{font-size:7.5px}
  .calendar-detail-heading{padding:15px 17px 12px}
  .calendar-detail-list{padding:0 17px}
  .timeline{padding:2px 15px}
  .timeline:before{left:19px}
  .lesson-card{grid-template-columns:9px minmax(0,1fr);gap:11px}
  .lesson-head{display:block}
  .song-tag{display:inline-block;max-width:100%;margin-top:8px}
  .lesson-date{font-size:15px}
  .lesson-content p{font-size:13px}
  .side-column{grid-template-columns:1fr}
  .learned-card{grid-column:auto}
  .report-footer{padding-top:20px}
  .manage-shell{width:calc(100% - 28px);padding-top:24px}
  .manage-card{padding:21px 18px}
  .form-grid{grid-template-columns:1fr}
  .form-field.full{grid-column:auto}
  .share-link{display:grid}
  .share-link button{height:42px}
}

@media print{
  body{background:#fff}
  .refresh-button{display:none!important}
  .site-shell{width:100%;padding:0}
  .report-header{position:static}
  .hero-card,.stat-card,.timeline,.side-card{break-inside:avoid;box-shadow:none}
  .content-grid{grid-template-columns:1fr}
  .side-column{position:static;grid-template-columns:repeat(2,1fr)}
}

@media(prefers-reduced-motion:reduce){
  *,*:before,*:after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
}