/* ===== CSS Variables (Design Tokens) ===== */
:root {
    --primary: #12948E;
    --primary-dark: #0D7A75;
    --primary-light: #E8F5F4;
    --primary-alpha: rgba(18, 148, 142, 0.1);
    --accent: #FBB316;
    --accent-dark: #E5A00E;
    --accent-light: #FEF3D5;
    --text: #333333;
    --text-secondary: #666666;
    --text-hint: #999999;
    --bg: #F5F7FA;
    --surface: #FFFFFF;
    --surface-alt: #F0F2F5;
    --success: #28A745;
    --error: #DC3545;
    --warning: #FFC107;
    --divider: #E0E0E0;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.15);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --sidebar-w: 250px;
    --curriculum-w: 330px;
    --header-h: 56px;
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Reset ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:14px;scroll-behavior:smooth}
body{font-family:'Open Sans',sans-serif;color:var(--text);background:var(--bg);line-height:1.6;overflow:hidden;height:100vh}
h1,h2,h3,h4,h5{font-family:'Montserrat',sans-serif;font-weight:700;line-height:1.3}
a{color:var(--primary);text-decoration:none;transition:color .2s var(--ease)}
a:hover{color:var(--primary-dark)}
button{cursor:pointer;border:none;background:none;font-family:inherit;font-size:inherit}
input,textarea,select{font-family:inherit;font-size:inherit}
img{max-width:100%;display:block}
::-webkit-scrollbar{width:5px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:rgba(0,0,0,0.15);border-radius:3px}

/* ===== Buttons ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:10px 20px;border-radius:var(--radius-sm);font-weight:600;font-size:13px;transition:all .2s var(--ease);border:none;cursor:pointer}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark);transform:translateY(-1px);box-shadow:0 4px 12px rgba(18,148,142,0.3)}
.btn-accent{background:var(--accent);color:#fff}
.btn-accent:hover{background:var(--accent-dark)}
.btn-outline{background:transparent;border:2px solid var(--primary);color:var(--primary)}
.btn-outline:hover{background:var(--primary);color:#fff}
.btn-ghost{color:var(--text-secondary);padding:6px 12px}
.btn-ghost:hover{background:var(--surface-alt);color:var(--primary)}
.btn-sm{padding:6px 14px;font-size:12px}
.btn-block{width:100%;padding:12px}
.btn .material-icons-round{font-size:18px}

/* ===== Form Elements ===== */
.form-group{margin-bottom:16px}
.form-group label{display:block;font-weight:600;font-size:12px;color:var(--text-secondary);margin-bottom:4px}
.input-wrap{position:relative;display:flex;align-items:center}
.input-wrap .icon{position:absolute;left:12px;color:var(--text-hint);font-size:20px}
.input-wrap input{width:100%;padding:10px 12px 10px 40px;border:2px solid var(--divider);border-radius:var(--radius-sm);background:var(--surface);color:var(--text);transition:border .2s var(--ease)}
.input-wrap input:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-alpha)}
.input-wrap .toggle-pw{position:absolute;right:10px;color:var(--text-hint);padding:4px;cursor:pointer}

/* ===== Cards ===== */
.card{background:var(--surface);border-radius:var(--radius);box-shadow:var(--shadow);transition:all .2s var(--ease)}
.card:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}

/* ===== Tags / Badges ===== */
.tag{display:inline-block;font-size:10px;font-weight:700;padding:2px 8px;border-radius:10px}
.tag-primary{background:var(--primary-light);color:var(--primary)}
.tag-accent{background:var(--accent-light);color:var(--accent-dark)}
.tag-error{background:#fde8ea;color:var(--error)}
.tag-success{background:#e8f5e9;color:var(--success)}

/* ===== Layout ===== */
.app-shell{display:flex;flex-direction:column;height:100vh;width:100vw}
.app-body{display:flex;flex:1;overflow:hidden}

/* ===== Header ===== */
.top-header{height:var(--header-h);background:var(--surface);border-bottom:1px solid var(--divider);display:flex;align-items:center;justify-content:space-between;padding:0 16px;flex-shrink:0;z-index:100}
.header-left{display:flex;align-items:center;gap:10px}
.header-right{display:flex;align-items:center;gap:6px}
.sidebar-toggle{width:36px;height:36px;display:flex;align-items:center;justify-content:center;border-radius:var(--radius-sm);color:var(--text-secondary);transition:all .2s}
.sidebar-toggle:hover{background:var(--surface-alt)}
.header-logo{display:flex;align-items:center;gap:8px}
.logo-icon{width:32px;height:32px;background:var(--primary);border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center}
.logo-icon .material-icons-round{font-size:20px;color:#fff}
.logo-text{font-family:'Montserrat',sans-serif;font-size:14px;color:var(--primary)}
.logo-text b{font-weight:800}
.header-search{display:flex;align-items:center;gap:8px;padding:7px 14px;background:var(--surface-alt);border-radius:20px;flex:1;max-width:400px;margin:0 16px}
.header-search .material-icons-round{color:var(--text-hint);font-size:18px}
.header-search input{flex:1;border:none;background:none;outline:none;font-size:13px}
.header-icon{width:36px;height:36px;display:flex;align-items:center;justify-content:center;border-radius:50%;color:var(--text-secondary);position:relative;transition:all .2s}
.header-icon:hover{background:var(--surface-alt);color:var(--primary)}
.notif-dot{position:absolute;top:6px;right:6px;width:16px;height:16px;background:var(--error);color:#fff;font-size:9px;font-weight:700;border-radius:50%;display:flex;align-items:center;justify-content:center;border:2px solid var(--surface)}
.header-user{display:flex;align-items:center;gap:6px;padding:3px 6px;border-radius:20px;cursor:pointer;transition:all .2s}
.header-user:hover{background:var(--surface-alt)}
.avatar{width:30px;height:30px;background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:11px;flex-shrink:0}
.avatar-lg{width:40px;height:40px;font-size:14px}

/* ===== Sidebar ===== */
.sidebar{width:var(--sidebar-w);background:var(--surface);border-right:1px solid var(--divider);display:flex;flex-direction:column;overflow-y:auto;flex-shrink:0;transition:margin .3s var(--ease),width .3s var(--ease)}
.sidebar.collapsed{margin-left:calc(-1 * var(--sidebar-w))}
.sidebar-user{display:flex;align-items:center;gap:10px;padding:16px}
.sidebar-user-info .name{font-weight:600;font-size:13px}
.sidebar-user-info .level{font-size:10px;font-weight:700;padding:1px 6px;background:var(--accent-light);color:var(--accent-dark);border-radius:8px;display:inline-block;margin-top:2px}
.nav-group{margin-bottom:4px}
.nav-label{padding:6px 16px;font-size:10px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;color:var(--text-hint)}
.nav-item{display:flex;align-items:center;gap:10px;padding:9px 16px;color:var(--text-secondary);font-size:13px;font-weight:500;transition:all .2s;border-radius:0 20px 20px 0;margin-right:10px;cursor:pointer}
.nav-item:hover{background:var(--primary-alpha);color:var(--primary)}
.nav-item.active{background:var(--primary);color:#fff;font-weight:600}
.nav-item .material-icons-round{font-size:20px}
.nav-badge{margin-left:auto;font-size:9px;font-weight:700;padding:1px 6px;background:var(--error);color:#fff;border-radius:8px}

/* ===== Main Content ===== */
.main-content{flex:1;overflow-y:auto;padding:20px}

/* ===== Login Page ===== */
.login-page{display:flex;height:100vh;width:100vw}
.login-left{flex:1;background:linear-gradient(135deg,#12948E 0%,#0D7A75 50%,#0a635f 100%);display:flex;align-items:center;justify-content:center;position:relative;overflow:hidden;padding:40px}
.login-left::before{content:'';position:absolute;width:300px;height:300px;border-radius:50%;border:2px solid rgba(255,255,255,.1);top:-60px;left:-80px}
.login-left::after{content:'';position:absolute;width:200px;height:200px;border-radius:50%;background:rgba(251,179,22,.1);bottom:-30px;right:-50px}
.login-brand{position:relative;z-index:2;color:#fff;max-width:460px}
.login-brand .logo{display:flex;align-items:center;gap:12px;margin-bottom:40px}
.login-brand .logo-box{width:48px;height:48px;background:rgba(255,255,255,.2);border-radius:var(--radius);display:flex;align-items:center;justify-content:center;backdrop-filter:blur(10px)}
.login-brand .logo-box .material-icons-round{font-size:28px;color:#fff}
.login-brand .brand-name{font-family:'Montserrat',sans-serif;font-size:20px;font-weight:700}
.login-brand .brand-sub{font-size:13px;opacity:.8;letter-spacing:1px}
.login-tagline{font-size:36px;font-weight:800;margin-bottom:12px;line-height:1.15}
.login-desc{font-size:14px;opacity:.85;margin-bottom:36px;line-height:1.7}
.login-stats{display:flex;gap:32px}
.login-stat .num{font-family:'Montserrat',sans-serif;font-size:24px;font-weight:800;color:var(--accent)}
.login-stat .lbl{font-size:12px;opacity:.8}
.login-right{width:440px;display:flex;align-items:center;justify-content:center;padding:32px;background:var(--surface)}
.login-form{width:100%;max-width:360px}
.login-form h2{font-size:24px;margin-bottom:4px}
.login-form .subtitle{color:var(--text-secondary);margin-bottom:24px;font-size:14px}
.form-options{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;font-size:12px}
.checkbox-wrap{display:flex;align-items:center;gap:6px;color:var(--text-secondary);cursor:pointer}
.checkbox-wrap input{width:14px;height:14px;accent-color:var(--primary)}
.forgot-link{color:var(--primary);font-weight:600}
.login-divider{text-align:center;margin:20px 0;position:relative;color:var(--text-hint);font-size:12px}
.login-divider::before,.login-divider::after{content:'';position:absolute;top:50%;width:calc(50% - 70px);height:1px;background:var(--divider)}
.login-divider::before{left:0}
.login-divider::after{right:0}
.social-btns{display:flex;gap:10px;margin-bottom:20px}
.btn-social{flex:1;display:flex;align-items:center;justify-content:center;gap:6px;padding:9px;border:2px solid var(--divider);border-radius:var(--radius-sm);font-weight:600;font-size:12px;color:var(--text);transition:all .2s}
.btn-social:hover{border-color:var(--text-hint);background:var(--surface-alt)}
.signup-text{text-align:center;font-size:12px;color:var(--text-secondary)}
.signup-text a{font-weight:600}
.korean-floating{position:absolute;right:-20px;top:50%;transform:translateY(-50%);display:flex;flex-direction:column;gap:20px}
.korean-floating span{font-size:48px;color:rgba(255,255,255,.06);font-weight:800;animation:float 6s ease-in-out infinite}
.korean-floating span:nth-child(2){animation-delay:2s}
.korean-floating span:nth-child(3){animation-delay:4s}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-12px)}}

/* ===== Dashboard ===== */
.welcome-banner{background:linear-gradient(135deg,var(--primary),var(--primary-dark));border-radius:var(--radius-lg);padding:28px;display:flex;align-items:center;justify-content:space-between;color:#fff;margin-bottom:20px;position:relative;overflow:hidden}
.welcome-banner::before{content:'';position:absolute;top:-50px;right:-50px;width:180px;height:180px;border-radius:50%;background:rgba(255,255,255,.05)}
.welcome-text h2{font-size:20px;margin-bottom:6px}
.welcome-text p{opacity:.9;font-size:13px;margin-bottom:16px}
.welcome-korean{text-align:center;z-index:1}
.welcome-korean .big{font-size:32px;font-weight:800;text-shadow:0 2px 10px rgba(0,0,0,.2)}
.welcome-korean .sub{font-size:13px;opacity:.8}

.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-bottom:24px}
.stat-card{background:var(--surface);border-radius:var(--radius);padding:16px;display:flex;align-items:center;gap:14px;box-shadow:var(--shadow);transition:all .2s var(--ease)}
.stat-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-md)}
.stat-icon{width:44px;height:44px;border-radius:var(--radius);display:flex;align-items:center;justify-content:center;flex-shrink:0}
.stat-icon .material-icons-round{font-size:22px}
.stat-value{font-family:'Montserrat',sans-serif;font-size:22px;font-weight:800}
.stat-label{font-size:11px;color:var(--text-secondary)}

.section-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px}
.section-head h3{font-size:16px}
.see-all{display:flex;align-items:center;gap:3px;font-size:12px;font-weight:600;color:var(--primary)}
.see-all .material-icons-round{font-size:14px}

.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}
.course-card{background:var(--surface);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);transition:all .25s var(--ease);cursor:pointer}
.course-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.course-thumb{position:relative;height:140px;display:flex;flex-direction:column;align-items:center;justify-content:center;color:#fff}
.course-thumb .korean{font-size:32px;font-weight:800;font-family:'Montserrat',sans-serif}
.course-thumb .level-text{font-size:13px;font-weight:600;opacity:.9}
.course-progress-bar{position:absolute;bottom:0;left:0;right:0;height:3px;background:rgba(0,0,0,.2)}
.course-progress-fill{height:100%;background:var(--accent);border-radius:0 2px 2px 0;transition:width .5s}
.course-body{padding:14px}
.course-title{font-size:14px;font-weight:600;margin-bottom:6px;line-height:1.4;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.course-meta{display:flex;gap:14px;font-size:11px;color:var(--text-secondary);margin-bottom:10px}
.course-meta span{display:flex;align-items:center;gap:3px}
.course-meta .material-icons-round{font-size:14px}
.course-footer{display:flex;justify-content:space-between;align-items:center;padding-top:10px;border-top:1px solid var(--divider)}
.course-pct{font-size:11px;font-weight:600;color:var(--primary)}

/* ===== Lesson Player ===== */
.lesson-main{flex:1;overflow-y:auto;display:flex;flex-direction:column}
.video-container{background:#1a1a2e;flex-shrink:0}
.video-placeholder{width:100%;aspect-ratio:16/9;max-height:460px;background:linear-gradient(180deg,#1a1a2e,#16213e);display:flex;align-items:center;justify-content:center;position:relative}
.play-btn{width:64px;height:64px;background:rgba(18,148,142,.9);border-radius:50%;display:flex;align-items:center;justify-content:center;color:#fff;transition:all .2s;box-shadow:0 4px 20px rgba(0,0,0,.3);z-index:2}
.play-btn:hover{transform:scale(1.1);background:var(--primary)}
.play-btn .material-icons-round{font-size:32px}
.video-brand{position:absolute;top:12px;right:12px;background:rgba(0,0,0,.5);color:#fff;padding:3px 10px;border-radius:4px;font-size:11px;font-weight:600;z-index:2}
.video-controls{background:#2d2d44;padding:6px 14px 8px}
.video-progress-bar{width:100%;height:4px;background:rgba(255,255,255,.2);border-radius:2px;cursor:pointer;margin-bottom:4px}
.video-progress-bar:hover{height:6px}
.video-progress-fill{height:100%;background:var(--primary);border-radius:2px}
.video-ctrl-row{display:flex;justify-content:space-between;align-items:center}
.video-ctrl-row .left,.video-ctrl-row .right{display:flex;align-items:center;gap:2px}
.ctrl-btn{width:32px;height:32px;display:flex;align-items:center;justify-content:center;color:rgba(255,255,255,.8);border-radius:50%;transition:all .2s}
.ctrl-btn:hover{color:#fff;background:rgba(255,255,255,.1)}
.ctrl-btn .material-icons-round{font-size:20px}
.video-time{color:rgba(255,255,255,.8);font-size:11px;font-variant-numeric:tabular-nums;margin-left:6px}

.lesson-info-bar{display:flex;justify-content:space-between;align-items:flex-start;padding:14px 20px;border-bottom:1px solid var(--divider);background:var(--surface)}
.lesson-title{font-size:16px;margin-bottom:2px}
.lesson-chapter{font-size:11px;color:var(--text-hint)}
.lesson-actions{display:flex;gap:4px}

.lesson-tabs{display:flex;padding:0 20px;border-bottom:1px solid var(--divider);background:var(--surface);overflow-x:auto}
.tab-btn{display:flex;align-items:center;gap:5px;padding:12px 14px;font-size:12px;font-weight:600;color:var(--text-secondary);border-bottom:3px solid transparent;transition:all .2s;white-space:nowrap}
.tab-btn:hover{color:var(--primary)}
.tab-btn.active{color:var(--primary);border-bottom-color:var(--primary)}
.tab-btn .material-icons-round{font-size:16px}
.tab-count{font-size:9px;background:var(--surface-alt);padding:1px 5px;border-radius:8px;font-weight:700}

.tab-panel{display:none;padding:20px;background:var(--surface);flex:1}
.tab-panel.active{display:block}

.doc-content h3{margin-bottom:10px;font-size:15px}
.doc-content h4{margin:16px 0 10px;font-size:14px;color:var(--primary)}
.doc-content p{margin-bottom:14px;color:var(--text-secondary);line-height:1.7}
.doc-content img{border-radius:var(--radius);margin:10px 0}

.tip-box{display:flex;gap:10px;padding:14px;background:var(--accent-light);border-radius:var(--radius);border-left:4px solid var(--accent);margin-top:16px}
.tip-box .material-icons-round{color:var(--accent);font-size:20px;flex-shrink:0}
.tip-box strong{color:var(--accent-dark)}

/* Comments */
.comment-input-wrap{display:flex;gap:10px;margin-bottom:20px}
.comment-input-wrap input{flex:1;padding:9px 14px;border:2px solid var(--divider);border-radius:20px;font-size:13px;outline:none;transition:border .2s}
.comment-input-wrap input:focus{border-color:var(--primary)}
.comment-item{display:flex;gap:10px;margin-bottom:14px;padding-bottom:14px;border-bottom:1px solid var(--divider)}
.comment-item:last-child{border-bottom:none}
.comment-author{font-weight:600;font-size:12px;margin-right:6px}
.comment-time{font-size:10px;color:var(--text-hint)}
.comment-body{margin-top:3px;font-size:13px;color:var(--text-secondary)}
.comment-actions{margin-top:4px;display:flex;gap:10px}
.comment-actions button{font-size:11px;color:var(--text-hint);display:flex;align-items:center;gap:3px}
.comment-actions button:hover{color:var(--primary)}
.reply-list{margin-left:42px;margin-top:8px}

/* Notes */
.note-form textarea{width:100%;min-height:100px;padding:12px;border:2px solid var(--divider);border-radius:var(--radius);font-size:13px;resize:vertical;outline:none;transition:border .2s;margin-bottom:10px}
.note-form textarea:focus{border-color:var(--primary)}
.note-item{display:flex;gap:10px;padding:12px;background:var(--surface-alt);border-radius:var(--radius);margin-bottom:8px}
.note-item .timestamp{font-size:11px;color:var(--primary);font-weight:600;white-space:nowrap;cursor:pointer}
.note-item .content{flex:1;font-size:13px;color:var(--text-secondary)}
.note-item .actions{display:flex;gap:4px}

/* ===== Curriculum Sidebar ===== */
.curriculum-sidebar{width:var(--curriculum-w);background:var(--surface);border-left:1px solid var(--divider);display:flex;flex-direction:column;overflow-y:auto;flex-shrink:0;transition:margin .3s var(--ease)}
.curriculum-sidebar.collapsed{margin-right:calc(-1 * var(--curriculum-w))}
.curriculum-header{display:flex;justify-content:space-between;align-items:center;padding:14px 16px;border-bottom:1px solid var(--divider)}
.curriculum-header h3{font-size:14px}

.progress-overview{display:flex;align-items:center;gap:12px;padding:14px 16px;background:var(--primary-light);margin:10px;border-radius:var(--radius)}
.progress-ring{position:relative;width:44px;height:44px;flex-shrink:0}
.progress-ring svg{width:44px;height:44px;transform:rotate(-90deg)}
.progress-ring-bg{fill:none;stroke:var(--divider);stroke-width:3}
.progress-ring-fill{fill:none;stroke:var(--primary);stroke-width:3;stroke-linecap:round;transition:stroke-dasharray .6s}
.progress-ring-text{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);font-size:10px;font-weight:800;color:var(--primary)}
.progress-info span{display:block;font-size:11px;font-weight:600}
.progress-info .sub{font-weight:400;color:var(--text-secondary);font-size:10px;margin-top:1px}

.curriculum-search{display:flex;align-items:center;gap:6px;padding:7px 10px;margin:0 10px 10px;background:var(--surface-alt);border-radius:var(--radius-sm)}
.curriculum-search .material-icons-round{color:var(--text-hint);font-size:16px}
.curriculum-search input{flex:1;border:none;background:none;outline:none;font-size:12px}

.curriculum-list{flex:1;overflow-y:auto;padding:0 10px 10px}
.curr-section{margin-bottom:4px;border-radius:var(--radius-sm);overflow:hidden;border:1px solid var(--divider)}
.section-toggle{width:100%;display:flex;justify-content:space-between;align-items:center;padding:10px 12px;background:var(--surface-alt);text-align:left;transition:all .2s}
.section-toggle:hover{background:var(--primary-light)}
.section-toggle .title{font-size:12px;font-weight:600;display:flex;align-items:center;gap:3px}
.section-toggle .title .material-icons-round{font-size:18px;color:var(--text-secondary);transition:transform .2s}
.section-toggle .progress{font-size:10px;color:var(--text-hint);font-weight:600}
.section-lessons{background:var(--surface);display:none}
.curr-section.expanded .section-lessons{display:block}
.curr-section.expanded .section-toggle .title .material-icons-round{transform:rotate(90deg)}
.lesson-row{display:flex;align-items:center;gap:8px;padding:8px 12px 8px 16px;font-size:12px;color:var(--text-secondary);transition:all .2s;cursor:pointer;border-left:3px solid transparent}
.lesson-row:hover{background:var(--primary-alpha);color:var(--primary)}
.lesson-row.active{background:var(--primary-light);color:var(--primary);border-left-color:var(--primary);font-weight:600}
.lesson-row.completed .check .material-icons-round{color:var(--success)}
.lesson-row .check .material-icons-round{font-size:16px;color:var(--divider)}
.lesson-row .name{flex:1;line-height:1.4}
.lesson-row .dur{font-size:10px;color:var(--text-hint);flex-shrink:0}

/* ===== Page Header ===== */
.page-header{margin-bottom:20px}
.page-header h2{font-size:20px;margin-bottom:2px}
.page-subtitle{font-size:13px;color:var(--text-secondary)}

/* ===== Stats Page ===== */
.streak-board{display:flex;justify-content:center;gap:16px}
.streak-day{display:flex;flex-direction:column;align-items:center;gap:6px}
.streak-day .day-label{font-size:11px;font-weight:600;color:var(--text-hint)}
.streak-day .day-dot .material-icons-round{font-size:28px;color:var(--divider);transition:all .3s}
.streak-day.active .day-dot .material-icons-round{color:#ff9800;filter:drop-shadow(0 2px 6px rgba(255,152,0,.4))}
.streak-day.today .day-dot .material-icons-round{font-size:32px}
.streak-day.today .day-label{color:var(--primary);font-weight:700}

.chart-container{display:flex;align-items:flex-end;justify-content:space-between;height:160px;gap:8px;padding:0 10px}
.chart-bar-wrap{display:flex;flex-direction:column;align-items:center;flex:1;height:100%;justify-content:flex-end}
.chart-bar{width:100%;max-width:40px;background:linear-gradient(180deg,var(--primary),var(--primary-dark));border-radius:6px 6px 0 0;min-height:4px;position:relative;transition:height .6s var(--ease)}
.chart-bar:hover{opacity:.85}
.chart-val{position:absolute;top:-18px;left:50%;transform:translateX(-50%);font-size:10px;font-weight:700;color:var(--primary);white-space:nowrap}
.chart-label{font-size:11px;color:var(--text-hint);font-weight:600;margin-top:6px}

.progress-row{margin-bottom:14px}
.progress-info-row{display:flex;justify-content:space-between;align-items:center;margin-bottom:4px}
.progress-bar-full{height:8px;background:var(--surface-alt);border-radius:4px;overflow:hidden}
.progress-bar-fill{height:100%;background:linear-gradient(90deg,var(--primary),var(--accent));border-radius:4px;transition:width .6s var(--ease)}

/* ===== Filter Tabs ===== */
.filter-tabs{display:flex;gap:6px;flex-wrap:wrap}
.filter-tab{padding:7px 16px;font-size:12px;font-weight:600;border-radius:20px;border:2px solid var(--divider);color:var(--text-secondary);background:var(--surface);transition:all .2s;cursor:pointer}
.filter-tab:hover{border-color:var(--primary);color:var(--primary)}
.filter-tab.active{background:var(--primary);color:#fff;border-color:var(--primary)}

/* ===== Favorites Page ===== */
.fav-list{display:flex;flex-direction:column;gap:8px}
.fav-item{display:flex;align-items:center;gap:14px;padding:14px 16px;cursor:pointer;transition:all .2s}
.fav-item:hover{transform:translateX(4px)}
.fav-icon{width:40px;height:40px;background:#fde8ea;border-radius:50%;display:flex;align-items:center;justify-content:center;flex-shrink:0}
.fav-info{flex:1}
.fav-title{font-weight:600;font-size:14px;display:block;margin-bottom:2px}
.fav-meta{font-size:11px;color:var(--text-secondary);display:flex;align-items:center;gap:4px}

/* ===== My Notes Page ===== */
.notes-list{display:flex;flex-direction:column;gap:10px}
.note-card{overflow:hidden}
.note-card-header{display:flex;justify-content:space-between;align-items:center;padding:12px 16px;background:var(--surface-alt);border-bottom:1px solid var(--divider)}
.note-lesson-name{display:flex;align-items:center;gap:4px;font-size:13px;font-weight:600;color:var(--primary)}
.note-timestamp{font-size:10px;background:var(--primary-light);color:var(--primary);padding:1px 6px;border-radius:8px;margin-left:8px;font-weight:700}
.note-date{font-size:11px;color:var(--text-hint)}
.note-card-body{padding:12px 16px;font-size:13px;line-height:1.7;color:var(--text-secondary)}
.note-card-footer{padding:8px 16px;border-top:1px solid var(--divider);display:flex;justify-content:flex-end}

/* ===== My Classes Page ===== */
.class-card{margin-bottom:14px;overflow:hidden}
.class-card-header{display:flex;justify-content:space-between;align-items:center;padding:16px;border-bottom:1px solid var(--divider)}
.progress-ring-sm{position:relative;width:36px;height:36px;flex-shrink:0}
.progress-ring-sm svg{width:36px;height:36px}
.class-lessons{max-height:300px;overflow-y:auto}
.class-lesson-row{display:flex;align-items:center;gap:10px;padding:10px 16px;border-bottom:1px solid var(--divider);cursor:pointer;transition:all .2s}
.class-lesson-row:last-child{border-bottom:none}
.class-lesson-row:hover{background:var(--primary-alpha)}
.class-lesson-title{display:block;font-size:13px;font-weight:500}
.class-lesson-meta{display:block;font-size:10px;color:var(--text-hint);margin-top:1px}

/* ===== Empty State ===== */
.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:60px 20px;text-align:center}
.empty-state p{margin-top:10px;font-size:14px;color:var(--text-secondary)}

/* ===== Responsive ===== */
@media(max-width:1200px){.curriculum-sidebar{width:280px}}
@media(max-width:992px){
    .sidebar{position:fixed;left:0;top:var(--header-h);bottom:0;z-index:200;margin-left:calc(-1 * var(--sidebar-w));box-shadow:none}
    .sidebar.open{margin-left:0;box-shadow:4px 0 20px rgba(0,0,0,.15)}
    .sidebar-overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.3);z-index:199}
    .sidebar-overlay.show{display:block}
    .stats-grid{grid-template-columns:repeat(2,1fr)}
    .curriculum-sidebar{position:fixed;right:0;top:var(--header-h);bottom:0;z-index:200;margin-right:calc(-1 * var(--curriculum-w));box-shadow:none}
    .curriculum-sidebar.open{margin-right:0;box-shadow:-4px 0 20px rgba(0,0,0,.15)}
}
@media(max-width:768px){
    .login-left{display:none}
    .login-right{width:100%}
    .stats-grid{grid-template-columns:1fr 1fr}
    .course-grid{grid-template-columns:1fr}
    .header-search{display:none}
    .welcome-korean{display:none}
}
@media(max-width:480px){
    .stats-grid{grid-template-columns:1fr}
    .welcome-banner{padding:20px}
    .welcome-text h2{font-size:16px}
    .lesson-tabs{padding:0 10px}
    .tab-btn{padding:10px 8px;font-size:11px}
}

/* ===== Animations ===== */
@keyframes fadeIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}
@keyframes spin{from{transform:rotate(0)}to{transform:rotate(360deg)}}
.fade-in{animation:fadeIn .4s ease-out}

/* ===== Loading ===== */
.spinner{width:20px;height:20px;border:2px solid var(--divider);border-top-color:var(--primary);border-radius:50%;animation:spin .6s linear infinite;display:inline-block}
.loading-page{display:flex;align-items:center;justify-content:center;height:100%;gap:10px;color:var(--text-secondary);font-size:14px}