@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:wght@300;400;500;600&display=swap');

*{box-sizing:border-box;margin:0;padding:0;}

:root{
  --red:#C0392B;--red2:#E74C3C;--red-soft:#FDF0EF;
  --dark:#1A1A1A;--dark2:#2D2D2D;
  --gray:#F7F6F4;--gray2:#EFEFED;--gray3:#D8D6D2;
  --tx:#1A1A1A;--tx2:#6B6860;--tx3:#A8A49E;
  --white:#FFFFFF;
  --radius:10px;--radius-lg:16px;--radius-xl:20px;
  --shadow:0 1px 3px rgba(0,0,0,.06),0 4px 12px rgba(0,0,0,.04);
  --shadow-md:0 2px 8px rgba(0,0,0,.08),0 8px 24px rgba(0,0,0,.06);
  --font:'Be Vietnam Pro',sans-serif;
  --nav-h:56px;
}

body{font-family:var(--font);background:var(--gray);color:var(--tx);font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased;}
a{text-decoration:none;color:inherit;}
button{font-family:var(--font);cursor:pointer;}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar{width:4px;}
::-webkit-scrollbar-track{background:transparent;}
::-webkit-scrollbar-thumb{background:var(--gray3);border-radius:99px;}

/* ===== NAV ===== */
.navbar{
  height:var(--nav-h);display:flex;align-items:center;justify-content:space-between;
  padding:0 20px;background:var(--white);
  border-bottom:1px solid var(--gray2);
  position:sticky;top:0;z-index:100;
}
.nav-logo{display:flex;align-items:center;gap:8px;font-size:16px;font-weight:600;cursor:pointer;color:var(--dark);}
.nav-logo img{width:32px;height:32px;object-fit:contain;}
.nav-center{display:flex;gap:2px;}
.nav-btn{padding:6px 12px;border-radius:8px;font-size:13px;font-weight:400;border:none;background:transparent;color:var(--tx2);transition:all .15s;}
.nav-btn:hover{background:var(--gray);color:var(--tx);}
.nav-btn.active{background:var(--gray);color:var(--tx);font-weight:500;}
.nav-btn.admin-btn{color:var(--red);}
.nav-right{display:flex;gap:8px;align-items:center;}
.btn-ghost{padding:7px 14px;border-radius:8px;font-size:13px;border:1px solid var(--gray3);background:transparent;color:var(--tx);transition:all .15s;}
.btn-ghost:hover{border-color:var(--dark);background:var(--gray);}
.btn-primary{padding:7px 16px;border-radius:8px;font-size:13px;font-weight:500;border:none;background:var(--red);color:#fff;transition:all .15s;}
.btn-primary:hover{background:var(--red2);}
.btn-primary:active{transform:scale(.98);}

/* ===== MOBILE NAV ===== */
.hamburger{display:none;width:36px;height:36px;border:1px solid var(--gray3);border-radius:8px;background:transparent;font-size:16px;align-items:center;justify-content:center;}
.mobile-drawer{display:none;position:fixed;top:var(--nav-h);left:0;right:0;background:var(--white);border-bottom:1px solid var(--gray2);padding:8px 12px 12px;z-index:99;flex-direction:column;gap:2px;box-shadow:var(--shadow-md);}
.mobile-drawer.open{display:flex;}
.mobile-drawer .nav-btn{text-align:left;padding:12px 14px;font-size:14px;border-radius:8px;}

/* ===== PAGES ===== */
.page{display:none;}
.page.active{display:block;}

/* ===== LANDING ===== */
.landing-hero{
  background:var(--white);
  border-bottom:1px solid var(--gray2);
  padding:60px 20px 48px;
  text-align:center;
}
.hero-eyebrow{
  display:inline-flex;align-items:center;gap:6px;
  background:var(--red-soft);color:var(--red);
  font-size:12px;font-weight:500;
  padding:5px 14px;border-radius:99px;
  margin-bottom:20px;
}
.hero-eyebrow::before{content:'';width:6px;height:6px;background:var(--red);border-radius:50%;}
.landing-hero h1{font-size:38px;font-weight:600;line-height:1.2;color:var(--dark);margin-bottom:14px;}
.landing-hero h1 em{font-style:normal;color:var(--red);}
.landing-hero p{font-size:15px;color:var(--tx2);margin-bottom:28px;max-width:440px;margin-left:auto;margin-right:auto;}
.hero-actions{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;}
.hero-actions .btn-primary{padding:11px 24px;font-size:14px;border-radius:10px;}
.hero-actions .btn-ghost{padding:11px 24px;font-size:14px;border-radius:10px;}

.landing-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--gray2);border-top:1px solid var(--gray2);}
.stat-block{background:var(--white);padding:24px 16px;text-align:center;}
.stat-block .num{font-size:26px;font-weight:600;color:var(--dark);}
.stat-block .lbl{font-size:12px;color:var(--tx3);margin-top:2px;}

.landing-features{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;padding:32px 20px;max-width:900px;margin:0 auto;}
.feat{background:var(--white);border:1px solid var(--gray2);border-radius:var(--radius-lg);padding:24px;}
.feat-ico{width:40px;height:40px;border-radius:10px;display:flex;align-items:center;justify-content:center;font-size:20px;margin-bottom:14px;}
.feat h3{font-size:14px;font-weight:600;margin-bottom:6px;}
.feat p{font-size:13px;color:var(--tx2);line-height:1.7;}

/* ===== AUTH ===== */
.auth-shell{min-height:calc(100vh - var(--nav-h));display:flex;align-items:center;justify-content:center;padding:24px 16px;}
.auth-box{background:var(--white);border:1px solid var(--gray2);border-radius:var(--radius-xl);padding:32px;width:100%;max-width:400px;box-shadow:var(--shadow);}
.auth-tabs{display:flex;background:var(--gray);border-radius:8px;padding:3px;margin-bottom:24px;}
.auth-tab{flex:1;padding:8px;border-radius:6px;font-size:13px;font-weight:500;border:none;background:transparent;color:var(--tx2);transition:all .15s;}
.auth-tab.active{background:var(--white);color:var(--tx);box-shadow:0 1px 3px rgba(0,0,0,.1);}
.auth-box h2{font-size:20px;font-weight:600;margin-bottom:4px;}
.auth-box p{font-size:13px;color:var(--tx2);margin-bottom:22px;}
.role-row{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-bottom:18px;}
.role-opt{padding:12px;border:1.5px solid var(--gray2);border-radius:10px;text-align:center;cursor:pointer;transition:all .15s;}
.role-opt:hover{border-color:var(--red);}
.role-opt.active{border-color:var(--red);background:var(--red-soft);}
.role-opt .ico{font-size:22px;display:block;margin-bottom:5px;}
.role-opt span{font-size:12px;font-weight:500;}
.field{margin-bottom:14px;}
.field label{font-size:12px;font-weight:500;color:var(--tx2);display:block;margin-bottom:5px;}
.field input,.field select{
  width:100%;padding:10px 12px;
  border:1.5px solid var(--gray2);border-radius:8px;
  font-size:14px;font-family:var(--font);
  background:var(--white);color:var(--tx);
  transition:border-color .15s;
}
.field input:focus,.field select:focus{outline:none;border-color:var(--red);}
.field-hint{font-size:11px;color:var(--tx3);margin-top:4px;}
.class-hint{background:var(--red-soft);border-radius:7px;padding:8px 10px;font-size:12px;color:var(--red);margin-top:5px;line-height:1.5;}
.btn-block{width:100%;padding:11px;border-radius:10px;font-size:14px;font-weight:500;border:none;background:var(--red);color:#fff;transition:all .15s;margin-top:4px;}
.btn-block:hover{background:var(--red2);}
.auth-footer{text-align:center;font-size:12px;color:var(--tx3);margin-top:14px;}
.auth-footer a{color:var(--red);cursor:pointer;}
.teacher-info{background:#FFF8E7;border:1px solid #F0C040;border-radius:8px;padding:10px 12px;font-size:12px;color:#7D5A00;margin-bottom:14px;display:none;}

/* ===== STUDENT SHELL ===== */
.app-shell{display:grid;grid-template-columns:200px 1fr;min-height:calc(100vh - var(--nav-h));}

/* SIDEBAR */
.app-sidebar{
  background:var(--white);border-right:1px solid var(--gray2);
  padding:20px 12px;position:sticky;top:var(--nav-h);
  height:calc(100vh - var(--nav-h));overflow-y:auto;
}
.user-card{padding:12px;background:var(--gray);border-radius:var(--radius-lg);margin-bottom:16px;}
.user-ava{width:40px;height:40px;border-radius:50%;background:var(--red-soft);color:var(--red);font-weight:600;font-size:14px;display:flex;align-items:center;justify-content:center;margin-bottom:8px;}
.user-name{font-size:13px;font-weight:600;line-height:1.3;}
.user-meta{font-size:11px;color:var(--tx3);margin-top:2px;}
.xp-row{display:flex;justify-content:space-between;font-size:11px;color:var(--tx3);margin:10px 0 4px;}
.xp-bar{height:4px;background:var(--gray2);border-radius:99px;overflow:hidden;}
.xp-fill{height:100%;background:var(--red);border-radius:99px;transition:width .5s;}

.nav-section{font-size:10px;font-weight:600;color:var(--tx3);letter-spacing:.06em;text-transform:uppercase;padding:14px 10px 6px;}
.nav-item{display:flex;align-items:center;gap:9px;padding:9px 10px;border-radius:8px;font-size:13px;color:var(--tx2);cursor:pointer;transition:all .15s;margin-bottom:1px;border:none;background:transparent;width:100%;text-align:left;font-family:var(--font);}
.nav-item:hover{background:var(--gray);color:var(--tx);}
.nav-item.active{background:var(--red-soft);color:var(--red);font-weight:500;}
.nav-item .ico{font-size:15px;width:18px;text-align:center;flex-shrink:0;}
.nav-badge{margin-left:auto;background:var(--red);color:#fff;font-size:10px;padding:1px 6px;border-radius:99px;}

/* MAIN */
.app-main{padding:24px;max-width:860px;}

/* ===== CARDS ===== */
.card{background:var(--white);border:1px solid var(--gray2);border-radius:var(--radius-lg);padding:20px;}
.card+.card{margin-top:16px;}
.card-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px;}
.card-title{font-size:14px;font-weight:600;}
.card-link{font-size:12px;color:var(--red);cursor:pointer;border:none;background:none;font-family:var(--font);}

/* ===== STAT CHIPS ===== */
.stat-chips{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:16px;}
.chip{background:var(--gray);border-radius:var(--radius);padding:14px;}
.chip .num{font-size:24px;font-weight:600;color:var(--dark);}
.chip .lbl{font-size:11px;color:var(--tx3);margin-top:2px;}

/* ===== VIDEO GRID ===== */
.vgrid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;}
.vcard{background:var(--white);border:1px solid var(--gray2);border-radius:var(--radius-lg);overflow:hidden;cursor:pointer;transition:all .2s;}
.vcard:hover{border-color:var(--red);transform:translateY(-2px);box-shadow:var(--shadow);}
.vthumb{height:90px;display:flex;align-items:center;justify-content:center;position:relative;}
.vplay{width:34px;height:34px;background:rgba(255,255,255,.25);backdrop-filter:blur(4px);border-radius:50%;display:flex;align-items:center;justify-content:center;color:#fff;font-size:13px;}
.vtag{position:absolute;top:0;left:0;background:rgba(0,0,0,.65);color:#fff;font-size:13px;font-weight:600;padding:6px 14px;border-radius:var(--radius-lg) 0 var(--radius) 0;backdrop-filter:blur(4px);letter-spacing:.01em;}
.vwatched{position:absolute;top:7px;right:8px;background:rgba(39,120,17,.85);color:#fff;font-size:10px;padding:2px 7px;border-radius:99px;}
.vmeta{padding:10px 12px;}
.vmeta h4{font-size:13px;font-weight:500;margin-bottom:2px;}
.vmeta p{font-size:11px;color:var(--tx3);}

/* ===== GAME GRID ===== */
.ggrid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;}
.gcard{background:var(--gray);border:1.5px solid transparent;border-radius:var(--radius-lg);padding:16px 12px;text-align:center;cursor:pointer;transition:all .2s;}
.gcard:hover{border-color:var(--red);background:var(--red-soft);}
.gico{font-size:28px;margin-bottom:8px;}
.gcard h4{font-size:13px;font-weight:500;margin-bottom:3px;}
.gcard p{font-size:11px;color:var(--tx3);}
.gtag{display:inline-block;margin-top:7px;background:var(--red);color:#fff;font-size:10px;padding:2px 8px;border-radius:99px;}

/* ===== RANKING ===== */
.rank-toggle{display:flex;background:var(--gray);border-radius:8px;padding:3px;margin-bottom:14px;}
.rtab{flex:1;padding:7px;border-radius:6px;font-size:12px;font-weight:500;border:none;background:transparent;color:var(--tx2);cursor:pointer;font-family:var(--font);transition:all .15s;}
.rtab.active{background:var(--white);color:var(--tx);box-shadow:0 1px 3px rgba(0,0,0,.08);}
.rank-list{display:flex;flex-direction:column;gap:6px;}
.ri{display:flex;align-items:center;gap:10px;padding:11px 14px;background:var(--gray);border-radius:var(--radius-lg);transition:all .15s;}
.ri:hover{background:var(--gray2);}
.ri.gold{background:#FFF8E7;border:1px solid #F0C040;}
.ri.silver{background:#F7F7F7;border:1px solid #D0D0D0;}
.ri.bronze{background:#FBF4EE;border:1px solid #D4A574;}
.ri.me{background:var(--red-soft);border:1px solid var(--red);}
.rpos{font-size:16px;width:28px;text-align:center;flex-shrink:0;}
.rava{width:34px;height:34px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:600;flex-shrink:0;}
.rinfo{flex:1;}
.rname{font-size:13px;font-weight:500;display:flex;align-items:center;gap:6px;}
.rlvl{font-size:11px;color:var(--tx3);}
.rxp{font-size:13px;font-weight:600;color:var(--red);}
.me-badge{font-size:10px;background:var(--red);color:#fff;padding:1px 6px;border-radius:99px;}

/* ===== NEWS ===== */
.news-list{display:flex;flex-direction:column;gap:8px;}
.nitem{background:var(--gray);border-radius:var(--radius-lg);padding:14px;display:flex;gap:12px;cursor:pointer;transition:all .15s;border:1px solid transparent;}
.nitem:hover{border-color:var(--gray3);}
.nico{width:36px;height:36px;border-radius:9px;display:flex;align-items:center;justify-content:center;font-size:17px;flex-shrink:0;}
.nbody{flex:1;}
.ntag{font-size:10px;font-weight:600;padding:2px 8px;border-radius:99px;display:inline-block;margin-bottom:4px;}
.ntitle{font-size:13px;font-weight:500;line-height:1.4;margin-bottom:2px;}
.ndesc{font-size:12px;color:var(--tx2);line-height:1.5;}
.ntime{font-size:11px;color:var(--tx3);margin-top:4px;}
.ndot{width:7px;height:7px;background:var(--red);border-radius:50%;flex-shrink:0;margin-top:4px;}

/* ===== PROGRESS ===== */
.pbar{height:5px;background:var(--gray2);border-radius:99px;overflow:hidden;margin:4px 0;}
.pfill{height:100%;background:var(--red);border-radius:99px;transition:width .5s;}
.prog-row{margin-bottom:14px;}
.prog-label{display:flex;justify-content:space-between;font-size:12px;margin-bottom:4px;}
.prog-label span:last-child{color:var(--tx3);}

/* ===== TEACHER ===== */
.teacher-shell{padding:24px;max-width:960px;margin:0 auto;}
.page-header{display:flex;align-items:flex-start;justify-content:space-between;margin-bottom:24px;gap:16px;}
.page-header h1{font-size:20px;font-weight:600;}
.page-header p{font-size:13px;color:var(--tx2);margin-top:2px;}
.t-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;}
.t-full{grid-column:1/-1;}

/* Char chips */
.char-grid{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:10px;}
.char-chip{width:42px;height:42px;border:1.5px solid var(--gray2);border-radius:9px;display:flex;align-items:center;justify-content:center;font-size:19px;cursor:pointer;background:var(--gray);transition:all .15s;user-select:none;}
.char-chip:hover,.char-chip.on{border-color:var(--red);background:var(--red-soft);}
.char-chip.add{border-style:dashed;color:var(--tx3);font-size:16px;}
.char-count{font-size:11px;color:var(--tx3);}

/* Game type */
.gtype-list{display:flex;flex-direction:column;gap:6px;}
.gtype{display:flex;align-items:center;justify-content:space-between;padding:10px 12px;border:1.5px solid var(--gray2);border-radius:var(--radius);cursor:pointer;transition:all .15s;}
.gtype:hover,.gtype.on{border-color:var(--red);background:var(--red-soft);}
.gtype-l{display:flex;align-items:center;gap:10px;}
.gtype-ico{font-size:18px;}
.gtype-name{font-size:13px;font-weight:500;}
.gtype-desc{font-size:11px;color:var(--tx2);}
.gcheck{color:var(--red);font-weight:600;}

/* Student table */
.tbl{width:100%;border-collapse:collapse;font-size:13px;}
.tbl th{text-align:left;padding:8px 10px;font-size:11px;font-weight:600;color:var(--tx3);border-bottom:1px solid var(--gray2);letter-spacing:.03em;text-transform:uppercase;}
.tbl td{padding:10px;border-bottom:1px solid var(--gray2);color:var(--tx);}
.tbl tr:last-child td{border-bottom:none;}
.tbl tr:hover td{background:var(--gray);}
.sbadge{display:inline-flex;align-items:center;gap:4px;font-size:11px;padding:3px 8px;border-radius:99px;font-weight:500;}
.sbadge.green{background:#E8F5E2;color:#2D7A1F;}
.sbadge.amber{background:#FFF3DC;color:#8A5F00;}
.sbadge.gray{background:var(--gray2);color:var(--tx2);}
.sbadge.teal{background:#E0F4F0;color:#1A6B5A;}
.sdot{width:5px;height:5px;border-radius:50%;background:currentColor;}

/* Video manager */
.vid-input-row{display:grid;grid-template-columns:1fr 80px;gap:8px;margin-bottom:8px;}
.vid-input-row2{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-bottom:8px;}
.inp{width:100%;padding:9px 12px;border:1.5px solid var(--gray2);border-radius:8px;font-size:13px;font-family:var(--font);background:var(--white);color:var(--tx);transition:border-color .15s;}
.inp:focus{outline:none;border-color:var(--red);}
.sel{width:100%;padding:9px 12px;border:1.5px solid var(--gray2);border-radius:8px;font-size:13px;font-family:var(--font);background:var(--white);color:var(--tx);}
.vid-item{display:flex;align-items:center;gap:10px;padding:9px 12px;background:var(--gray);border-radius:var(--radius);margin-bottom:6px;}
.vid-order{width:28px;height:28px;background:var(--red-soft);color:var(--red);border-radius:7px;display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:600;flex-shrink:0;}
.vid-info{flex:1;}
.vid-title{font-size:13px;font-weight:500;}
.vid-meta{font-size:11px;color:var(--tx3);}

/* ===== ADMIN ===== */
.admin-shell{padding:24px;max-width:960px;margin:0 auto;}
.admin-kpi{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:20px;}
.kpi{background:var(--white);border:1px solid var(--gray2);border-radius:var(--radius-lg);padding:16px 20px;}
.kpi .num{font-size:26px;font-weight:600;color:var(--dark);}
.kpi .lbl{font-size:12px;color:var(--tx3);margin-top:2px;}
.admin-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;}
.admin-full{grid-column:1/-1;}

/* Teacher account */
.ta-item{display:flex;align-items:center;gap:12px;padding:11px 0;border-bottom:1px solid var(--gray2);}
.ta-item:last-child{border-bottom:none;}
.ta-ava{width:36px;height:36px;border-radius:50%;background:var(--red-soft);color:var(--red);font-size:12px;font-weight:600;display:flex;align-items:center;justify-content:center;flex-shrink:0;}
.ta-info{flex:1;}
.ta-name{font-size:13px;font-weight:500;}
.ta-email{font-size:11px;color:var(--tx3);}
.ta-btns{display:flex;gap:6px;}
.btn-sm{padding:5px 10px;border-radius:6px;font-size:12px;font-weight:500;border:1px solid var(--gray3);background:transparent;color:var(--tx);cursor:pointer;font-family:var(--font);transition:all .15s;}
.btn-sm:hover{background:var(--gray);}
.btn-sm.danger{border-color:#FFCDD2;color:#C0392B;background:#FDF5F5;}
.btn-sm.danger:hover{background:#FFCDD2;}
.btn-sm.success{border-color:#C8E6C9;color:#2D7A1F;background:#F1F8F0;}

/* Class card */
.class-card{background:var(--gray);border:1.5px solid transparent;border-radius:var(--radius-lg);padding:14px 16px;cursor:pointer;transition:all .15s;display:flex;align-items:center;gap:14px;margin-bottom:8px;}
.class-card:hover{border-color:var(--red);background:var(--red-soft);}
.class-badge{width:44px;height:44px;background:var(--red-soft);color:var(--red);border-radius:10px;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:700;flex-shrink:0;}
.class-info{flex:1;}
.class-name{font-size:14px;font-weight:600;}
.class-meta{font-size:12px;color:var(--tx3);margin-top:2px;}
.class-pay{text-align:right;}
.class-pay .num{font-size:14px;font-weight:600;}
.class-pay .lbl{font-size:11px;color:var(--tx3);}

/* Activity log */
.log-item{display:flex;align-items:center;gap:10px;padding:9px 0;border-bottom:1px solid var(--gray2);font-size:13px;}
.log-item:last-child{border-bottom:none;}
.log-ico{font-size:15px;flex-shrink:0;}
.log-txt{flex:1;font-weight:500;}
.log-time{font-size:11px;color:var(--tx3);}

/* ===== MODAL ===== */
.overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.4);z-index:9999;align-items:center;justify-content:center;padding:16px;}
.overlay.open{display:flex;}
.modal{background:var(--white);border-radius:var(--radius-xl);padding:24px;width:100%;max-width:480px;max-height:90vh;overflow-y:auto;box-shadow:var(--shadow-md);}
.modal-wide{max-width:760px;}
.mhead{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px;}
.mhead h3{font-size:16px;font-weight:600;}
.mclose{width:32px;height:32px;border-radius:8px;border:1px solid var(--gray2);background:transparent;font-size:17px;cursor:pointer;display:flex;align-items:center;justify-content:center;color:var(--tx2);}
.mclose:hover{background:var(--gray);}

/* Mini stat row in modal */
.mini-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-bottom:18px;}
.mini-stat{background:var(--gray);border-radius:var(--radius);padding:12px;text-align:center;}
.mini-stat .num{font-size:20px;font-weight:600;}
.mini-stat .lbl{font-size:11px;color:var(--tx3);margin-top:2px;}

/* Session table */
.sess-tbl{width:100%;border-collapse:collapse;font-size:12px;}
.sess-tbl th{padding:7px 8px;font-size:10px;font-weight:600;color:var(--tx3);border-bottom:1px solid var(--gray2);text-transform:uppercase;letter-spacing:.04em;text-align:left;}
.sess-tbl td{padding:7px 8px;border-bottom:1px solid var(--gray2);}
.sess-tbl input[type=date],.sess-tbl input[type=time],.sess-tbl input[type=text]{padding:5px 7px;border:1px solid var(--gray2);border-radius:6px;font-size:12px;font-family:var(--font);background:var(--white);color:var(--tx);width:100%;}
.sess-tbl select{padding:5px 6px;border:1px solid var(--gray2);border-radius:6px;font-size:12px;font-family:var(--font);background:var(--white);}

/* Payment select */
select.pay-sel{font-size:12px;padding:4px 8px;border-radius:6px;border:1px solid var(--gray2);cursor:pointer;}
select.pay-sel.paid{background:#E8F5E2;color:#2D7A1F;border-color:#A8D5A0;}
select.pay-sel.unpaid{background:#FDF5F5;color:#C0392B;border-color:#FFCDD2;}

/* Admin login modal */
.admin-login-modal{max-width:360px;}
.remember-row{display:flex;align-items:center;gap:8px;margin-bottom:12px;}
.remember-row input{width:15px;height:15px;}
.remember-row label{font-size:13px;color:var(--tx2);cursor:pointer;}

/* ===== BUTTONS ===== */
.btn-red{padding:9px 18px;background:var(--red);color:#fff;border:none;border-radius:9px;font-size:13px;font-weight:500;cursor:pointer;font-family:var(--font);transition:all .15s;}
.btn-red:hover{background:var(--red2);}
.btn-outline{padding:9px 18px;background:transparent;color:var(--tx);border:1px solid var(--gray3);border-radius:9px;font-size:13px;font-weight:500;cursor:pointer;font-family:var(--font);transition:all .15s;}
.btn-outline:hover{background:var(--gray);}
.btn-row{display:flex;gap:8px;margin-top:16px;}
.btn-row .btn-red,.btn-row .btn-outline{flex:1;text-align:center;}

/* ===== RESPONSIVE ===== */
@media(max-width:768px){
  .nav-center{display:none;}
  .hamburger{display:flex;}
  .nav-right .btn-ghost{display:none;}
  .btn-primary{padding:6px 12px;font-size:12px;}

  .app-shell{grid-template-columns:1fr;}
  .app-sidebar{display:none;}
  .app-sidebar.open{display:block;position:fixed;top:var(--nav-h);left:0;bottom:0;width:240px;z-index:98;box-shadow:var(--shadow-md);overflow-y:auto;}
  .app-main{padding:16px;}

  .landing-hero{padding:40px 16px 32px;}
  .landing-hero h1{font-size:26px;}
  .landing-stats{grid-template-columns:repeat(2,1fr);}
  .landing-features{grid-template-columns:1fr;padding:20px 16px;}

  .auth-shell{padding:16px;}
  .auth-box{padding:22px 18px;}

  .stat-chips{gap:8px;}
  .chip .num{font-size:20px;}
  .vgrid{grid-template-columns:1fr;}
  .ggrid{grid-template-columns:repeat(2,1fr);}

  .teacher-shell,.admin-shell{padding:16px;}
  .page-header{flex-direction:column;}
  .page-header .btn-red{width:100%;}
  .t-grid,.admin-grid{grid-template-columns:1fr;}
  .t-full,.admin-full{grid-column:1;}
  .admin-kpi{grid-template-columns:repeat(2,1fr);}

  .modal{padding:18px 16px;}
  .mini-stats{gap:6px;}
  .mini-stat .num{font-size:17px;}
  .tbl th:nth-child(3),.tbl td:nth-child(3),
  .tbl th:nth-child(4),.tbl td:nth-child(4){display:none;}
}

@media(max-width:400px){
  .ggrid{grid-template-columns:1fr;}
  .admin-kpi{grid-template-columns:1fr 1fr;}
  .landing-hero h1{font-size:22px;}
  .stat-chips{grid-template-columns:1fr 1fr;}
  .stat-chips .chip:last-child{grid-column:1/-1;}
}

/* Mobile bottom nav */
.bottom-nav{display:none;position:fixed;bottom:0;left:0;right:0;background:var(--white);border-top:1px solid var(--gray2);padding:6px 0 env(safe-area-inset-bottom);z-index:97;}
.bottom-nav-inner{display:flex;justify-content:space-around;}
.bnav-item{display:flex;flex-direction:column;align-items:center;gap:2px;padding:6px 12px;border:none;background:transparent;color:var(--tx3);font-size:10px;font-family:var(--font);cursor:pointer;transition:all .15s;border-radius:8px;}
.bnav-item.active{color:var(--red);}
.bnav-item .ico{font-size:18px;}
@media(max-width:768px){
  .bottom-nav{display:block;}
  .app-main{padding-bottom:70px;}
  .auth-shell{padding-bottom:80px;}
}


/* ===== TÀI LIỆU ===== */
.doc-filter-btn{
  padding:5px 14px;border-radius:99px;font-size:12px;font-weight:500;
  border:1.5px solid var(--gray2);background:transparent;
  color:var(--tx2);cursor:pointer;font-family:var(--font);transition:all .15s;
}
.doc-filter-btn:hover{border-color:var(--red);color:var(--red);}
.doc-filter-btn.active{border-color:var(--red);background:var(--red-soft);color:var(--red);}

.doc-card{
  display:flex;align-items:center;gap:14px;
  padding:14px 16px;background:var(--white);
  border:1.5px solid var(--gray2);border-radius:var(--radius-lg);
  margin-bottom:8px;cursor:pointer;transition:all .15s;text-decoration:none;
}
.doc-card:hover{border-color:var(--red);background:var(--red-soft);}
.doc-icon{
  width:44px;height:44px;border-radius:10px;
  display:flex;align-items:center;justify-content:center;
  font-size:22px;flex-shrink:0;
}
.doc-info{flex:1;}
.doc-title{font-size:14px;font-weight:500;color:var(--tx);margin-bottom:3px;}
.doc-meta{font-size:12px;color:var(--tx3);}
.doc-tag{
  font-size:11px;font-weight:500;padding:3px 9px;border-radius:99px;
  display:inline-block;margin-top:4px;
}
.doc-tag.grammar{background:#E8F5E2;color:#2D7A1F;}
.doc-tag.vocab{background:#E6F1FB;color:#185FA5;}
.doc-tag.exercise{background:#FFF8E7;color:#8A5F00;}
.doc-tag.other{background:var(--gray2);color:var(--tx2);}
.doc-arrow{color:var(--tx3);font-size:18px;flex-shrink:0;}
.doc-empty{text-align:center;padding:32px;color:var(--tx3);font-size:13px;}
.doc-empty .ico{font-size:32px;margin-bottom:8px;}

.admin-doc-item{
  display:flex;align-items:center;gap:12px;
  padding:12px 14px;background:var(--gray);
  border-radius:var(--radius-lg);margin-bottom:8px;
}
.admin-doc-item .doc-icon{width:38px;height:38px;font-size:18px;}
.admin-doc-info{flex:1;}
.admin-doc-title{font-size:13px;font-weight:500;}
.admin-doc-meta{font-size:11px;color:var(--tx3);margin-top:2px;}

/* ===== MOBILE TOUCH IMPROVEMENTS ===== */
@media(max-width:768px){
  .nav-item{min-height:44px;}
  .bnav-item{min-height:52px;padding:6px 4px;font-size:9px;}
  .bnav-item .ico{font-size:20px;}
  .btn-red,.btn-outline,.btn-block{min-height:44px;}
  .btn-sm{min-height:36px;padding:6px 12px;}
  .doc-filter-btn{min-height:36px;padding:7px 14px;}
  .auth-tab{min-height:40px;}
  .role-opt{min-height:70px;}
  .field input,.field select,.inp,.sel{font-size:16px !important;}
  .vthumb{height:120px;}
  .doc-card{padding:16px;}
  .doc-icon{width:48px;height:48px;font-size:24px;}
  .gcard{padding:18px 12px;}
  .gico{font-size:32px;}
  .ri{padding:12px 14px;}
  .char-chip{width:46px;height:46px;font-size:20px;}
  .vid-input-row2{grid-template-columns:1fr;}
  #doc-filter-row{flex-wrap:nowrap;overflow-x:auto;-webkit-overflow-scrolling:touch;padding-bottom:4px;}
  #doc-filter-row::-webkit-scrollbar{display:none;}
  #doc-search{width:100% !important;}
  .card-head{flex-wrap:wrap;gap:8px;}
  .app-main{overflow-x:hidden;}
  .tbl{display:block;overflow-x:auto;-webkit-overflow-scrolling:touch;}
  .sess-tbl{display:block;overflow-x:auto;}
  .modal{
    border-radius:var(--radius-lg) var(--radius-lg) 0 0;
    position:fixed;bottom:0;left:0;right:0;
    max-width:100% !important;width:100% !important;
    max-height:90vh;margin:0;
  }
  .overlay{align-items:flex-end;padding:0;}
}

@media(max-width:380px){
  .ggrid{grid-template-columns:1fr;}
  .landing-hero h1{font-size:22px;}
  .admin-kpi{grid-template-columns:1fr 1fr;}
}

#game-modal{z-index:10001 !important;}