/* EduViet theme v3 */
:root{
  --edu-primary:#4f46e5; --edu-primary-dark:#4338ca; --edu-accent:#14b8a6; --edu-ink:#1e2a5a;
  --edu-bg:#f6f7fd; --edu-card:#fff; --edu-surface:#fff; --edu-soft:#eeedfd; --edu-soft-hover:#e2e5f5;
  --edu-border:#e6e8f5; --edu-muted:#6b7394; --edu-nav-bg:rgba(255,255,255,.80);
  --edu-skel-a:#eceef9; --edu-skel-b:#f8f9fe;
  --edu-ease:cubic-bezier(.22,.61,.36,1);
  --edu-shadow-sm:0 1px 2px rgba(30,42,90,.05),0 1px 3px rgba(30,42,90,.04);
  --edu-shadow-md:0 8px 24px rgba(30,42,90,.08);
  --edu-shadow-lg:0 20px 50px rgba(30,42,90,.14);
  --edu-font:'Be Vietnam Pro','Segoe UI',Roboto,Arial,sans-serif;
  /* Tương thích các trang edu_online viết cho Velzon */
  --vz-primary:#4f46e5; --vz-primary-rgb:79,70,229; --vz-primary-bg-subtle:#e8e7fc;
  --vz-success:#14b8a6; --vz-info:#0ea5e9; --vz-warning:#f59e0b; --vz-danger:#ef4444;
  --vz-light:#f3f4fb; --vz-body-color:#2b3252; --vz-secondary-color:#6b7394;
  --vz-border-color:#e6e8f5; --vz-card-bg:#fff; --vz-header-height:70px;
  --bs-primary:#4f46e5; --bs-primary-rgb:79,70,229; --bs-link-color:#4f46e5;
}
[data-bs-theme=dark]{
  --edu-ink:#e8ebff; --edu-bg:#0e1124; --edu-card:#171a33; --edu-surface:#171a33; --edu-soft:#262463; --edu-soft-hover:#2b3060;
  --edu-border:#272b4d; --edu-muted:#9aa2cc; --edu-nav-bg:rgba(14,17,36,.78);
  --edu-skel-a:#1f2344; --edu-skel-b:#292e55;
  --edu-shadow-sm:0 1px 2px rgba(0,0,0,.3); --edu-shadow-md:0 8px 24px rgba(0,0,0,.35); --edu-shadow-lg:0 20px 50px rgba(0,0,0,.5);
  --vz-primary-bg-subtle:#262463; --vz-light:#1c2040; --vz-body-color:#d8dcf7; --vz-secondary-color:#9aa2cc;
  --vz-border-color:#272b4d; --vz-card-bg:#171a33;
  --bs-link-color:#8b85ff; --bs-body-bg:#0e1124; --bs-border-color:#272b4d;
}

/* ===== Nền tảng ===== */
html{scroll-behavior:smooth;scroll-padding-top:84px;-webkit-text-size-adjust:100%}
body{font-family:var(--edu-font);background:var(--edu-bg);color:var(--vz-body-color);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
::selection{background:rgba(79,70,229,.22)}
:focus-visible{outline:2px solid var(--edu-primary);outline-offset:2px;border-radius:6px}
a{transition:color .15s}
img{max-width:100%;height:auto}
.main-content{min-height:70vh}
.page-content{padding:calc(var(--vz-header-height) + 1.25rem) 1rem 2rem}
.page-title-box{margin-bottom:1.25rem}

/* Thanh cuộn gọn (trình duyệt hỗ trợ) */
*{scrollbar-width:thin;scrollbar-color:#b9bde0 transparent}
[data-bs-theme=dark] *{scrollbar-color:#3a3f6b transparent}

/* Chuyển trang mượt (Chrome/Edge/Safari mới): hai trang giao nhau mờ dần, thanh menu đứng yên */
@view-transition{navigation:auto}
.edu-nav{view-transition-name:edu-nav}
::view-transition-old(root),::view-transition-new(root){animation-duration:.22s}
/* Trình duyệt chưa hỗ trợ thì dùng hiệu ứng hiện dần */
@supports not (view-transition-name:none){body{animation:eduPageIn .35s var(--edu-ease) both}}
@keyframes eduPageIn{from{opacity:0}to{opacity:1}}

/* Đổi sáng/tối mượt */
html.edu-theme-anim *,html.edu-theme-anim *::before,html.edu-theme-anim *::after{transition:background-color .3s,color .3s,border-color .3s,box-shadow .3s!important}

/* Thanh tiến trình trên cùng */
#edu-progress{position:fixed;top:0;left:0;height:3px;width:0;z-index:2000;pointer-events:none;opacity:0;
  background:linear-gradient(90deg,#4f46e5,#14b8a6);box-shadow:0 0 10px rgba(79,70,229,.5);transition:width .3s var(--edu-ease),opacity .3s}

/* ===== Thành phần chung ===== */
.btn{transition:transform .15s var(--edu-ease),box-shadow .2s,background-color .2s,border-color .2s,color .2s}
.btn:active{transform:scale(.97)}
.btn-primary{--bs-btn-bg:#4f46e5;--bs-btn-border-color:#4f46e5;--bs-btn-hover-bg:#4338ca;--bs-btn-hover-border-color:#4338ca;--bs-btn-active-bg:#3730a3}
.btn-outline-primary{--bs-btn-color:#4f46e5;--bs-btn-border-color:#4f46e5;--bs-btn-hover-bg:#4f46e5;--bs-btn-hover-border-color:#4f46e5}
.btn-success{--bs-btn-bg:#14b8a6;--bs-btn-border-color:#14b8a6;--bs-btn-hover-bg:#0f9f8f;--bs-btn-hover-border-color:#0f9f8f;--bs-btn-active-bg:#0d8a7c;--bs-btn-active-border-color:#0d8a7c}
.card{--bs-card-bg:var(--edu-card);border:1px solid var(--edu-border);border-radius:16px;box-shadow:var(--edu-shadow-sm)}
.form-control,.form-select{border-radius:11px;border-color:var(--edu-border);transition:border-color .15s,box-shadow .15s}
.form-control:focus,.form-select:focus{border-color:var(--edu-primary);box-shadow:0 0 0 .22rem rgba(79,70,229,.16)}
.modal-content{border:0;border-radius:18px;box-shadow:var(--edu-shadow-lg)}
.modal.fade .modal-dialog{transform:translateY(16px) scale(.98);transition:transform .25s var(--edu-ease)}
.modal.show .modal-dialog{transform:none}
.dropdown-menu{border-radius:14px;padding:.4rem;border:1px solid var(--edu-border)}
.dropdown-menu.show{animation:eduPop .18s var(--edu-ease)}
.dropdown-item{border-radius:9px;padding:.5rem .75rem}
@keyframes eduPop{from{opacity:0;translate:0 6px}to{opacity:1;translate:0 0}}
.nav-pills .nav-link{border-radius:10px;font-weight:600;color:var(--edu-muted)}
.nav-pills .nav-link.active{background:var(--edu-primary);color:#fff}
.table{--bs-table-bg:transparent}
.progress{border-radius:99px;background:var(--edu-soft)}
.progress-bar{background:linear-gradient(90deg,#4f46e5,#14b8a6);transition:width .8s var(--edu-ease)}
.swal2-popup{border-radius:20px!important;font-family:var(--edu-font)!important}
.swal2-styled.swal2-confirm{background:var(--edu-primary)!important;border-radius:11px!important}
.swal2-styled.swal2-cancel{border-radius:11px!important}

/* ===== Thanh menu ===== */
.edu-nav{position:fixed;top:0;left:0;right:0;z-index:1030;height:var(--vz-header-height);background:var(--edu-nav-bg);
  -webkit-backdrop-filter:saturate(1.6) blur(14px);backdrop-filter:saturate(1.6) blur(14px);border-bottom:1px solid var(--edu-border);transition:box-shadow .25s,background-color .25s}
.edu-nav.is-scrolled{box-shadow:var(--edu-shadow-md)}
.edu-brand{display:flex;align-items:center;gap:.6rem;font-weight:800;font-size:1.3rem;color:var(--edu-ink)}
.edu-logo{width:38px;height:38px;border-radius:11px;display:grid;place-items:center;color:#fff;font-size:1.3rem;background:linear-gradient(135deg,#4f46e5,#14b8a6);box-shadow:0 6px 14px rgba(79,70,229,.3);transition:transform .3s var(--edu-ease)}
.edu-brand:hover .edu-logo{transform:rotate(-8deg) scale(1.06)}
.edu-nav .nav-link{font-weight:500;color:var(--edu-ink);padding:.5rem .9rem;border-radius:10px;transition:background-color .2s,color .2s}
.edu-nav .nav-link:hover,.edu-nav .nav-link.active{color:var(--edu-primary);background:var(--edu-soft)}
[data-bs-theme=dark] .edu-nav .nav-link:hover,[data-bs-theme=dark] .edu-nav .nav-link.active{color:#a5a0ff}
.edu-nav .navbar-toggler:focus{box-shadow:none}
@media(max-width:991px){
  .edu-nav{height:auto;min-height:var(--vz-header-height)}
  .edu-nav .navbar-collapse{padding:.75rem 0 1rem}
  .edu-nav .navbar-collapse.show,.edu-nav .navbar-collapse.collapsing{animation:eduPop .2s var(--edu-ease)}
  .edu-nav-actions{flex-wrap:wrap;margin-top:.5rem}
}
.btn-edu{background:linear-gradient(135deg,#4f46e5,#6366f1);color:#fff;border:0;border-radius:11px;font-weight:600;padding:.55rem 1.1rem;box-shadow:0 6px 16px rgba(79,70,229,.28)}
.btn-edu:hover{color:#fff;transform:translateY(-2px);box-shadow:0 10px 24px rgba(79,70,229,.4)}
.btn-edu:active{transform:translateY(0) scale(.98)}
.btn-edu-ghost{border:1px solid var(--edu-border);background:var(--edu-surface);color:var(--edu-ink);border-radius:11px;font-weight:600;padding:.55rem 1.1rem}
.btn-edu-ghost:hover{border-color:var(--edu-primary);color:var(--edu-primary);background:var(--edu-surface)}
.edu-theme-btn{padding:0;font-size:1.1rem}
.edu-user{display:flex;align-items:center;gap:.5rem;font-weight:600;color:var(--edu-ink)}
.edu-avatar{width:32px;height:32px;border-radius:50%;display:grid;place-items:center;background:linear-gradient(135deg,#4f46e5,#14b8a6);color:#fff;font-size:.85rem}

/* ===== Trang chủ ===== */
.edu-hero{position:relative;overflow:hidden;padding:9rem 0 5rem;background:radial-gradient(900px 400px at 85% 0%,rgba(99,91,255,.22) 0%,transparent 60%),radial-gradient(700px 400px at 0% 30%,rgba(20,184,166,.2) 0%,transparent 60%)}
.edu-hero::before,.edu-hero::after{content:"";position:absolute;z-index:0;border-radius:50%;filter:blur(60px);opacity:.45;pointer-events:none;will-change:transform}
.edu-hero::before{width:320px;height:320px;right:-80px;top:40px;background:#6366f1;animation:eduFloat 14s ease-in-out infinite}
.edu-hero::after{width:260px;height:260px;left:-60px;bottom:-40px;background:#14b8a6;animation:eduFloat 18s ease-in-out infinite reverse}
.edu-hero>*{position:relative;z-index:1}
@keyframes eduFloat{0%,100%{transform:translate(0,0)}50%{transform:translate(24px,-28px)}}
.edu-hero h1{font-weight:800;font-size:clamp(2rem,4.5vw,3.4rem);line-height:1.2;color:var(--edu-ink)}
.edu-hero h1 span{background:linear-gradient(135deg,#4f46e5,#14b8a6);-webkit-background-clip:text;background-clip:text;color:transparent}
.edu-pill{display:inline-flex;gap:.4rem;align-items:center;padding:.35rem .8rem;border-radius:99px;background:var(--edu-surface);border:1px solid var(--edu-border);font-size:.85rem;font-weight:600;color:var(--edu-primary)}
.edu-stat b{display:block;font-size:1.6rem;color:var(--edu-ink);font-variant-numeric:tabular-nums}
.edu-mock{background:var(--edu-surface);border:1px solid var(--edu-border);border-radius:20px;padding:1rem;box-shadow:0 24px 60px rgba(79,70,229,.2)}
.edu-mock .board{border-radius:14px;background:#1e2a5a;color:#cfd6ff;padding:1.25rem;min-height:190px;font-family:ui-monospace,Menlo,Consolas,monospace;font-size:.9rem}
.edu-mock .seat{width:44px;height:44px;border-radius:50%;display:grid;place-items:center;color:#fff;font-weight:700;font-size:.85rem}
.edu-section{padding:4.5rem 0}
.edu-section h2{font-weight:800;color:var(--edu-ink)}
.edu-feature{padding:1.5rem;height:100%;transition:transform .25s var(--edu-ease),box-shadow .25s,border-color .25s}
.edu-feature:hover,.edu-course:hover{transform:translateY(-5px);box-shadow:var(--edu-shadow-lg);border-color:rgba(79,70,229,.35)}
.edu-ico{width:50px;height:50px;border-radius:14px;display:grid;place-items:center;font-size:1.5rem;background:var(--edu-soft);color:var(--edu-primary);margin-bottom:1rem;transition:transform .3s var(--edu-ease)}
.edu-feature:hover .edu-ico{transform:scale(1.1) rotate(-6deg)}
.edu-course{transition:transform .25s var(--edu-ease),box-shadow .25s,border-color .25s;height:100%;overflow:hidden}
.edu-course-thumb{position:relative;aspect-ratio:16/9;display:grid;place-items:center;font-size:2.6rem;color:#fff;background:linear-gradient(135deg,#4f46e5,#14b8a6);overflow:hidden}
.edu-course-thumb img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform .5s var(--edu-ease)}
.edu-course:hover .edu-course-thumb img{transform:scale(1.06)}
.edu-badge{display:inline-flex;align-items:center;gap:.25rem;padding:.2rem .6rem;border-radius:99px;font-size:.75rem;font-weight:600;background:var(--edu-soft);color:var(--edu-primary)}
.edu-chip{display:inline-flex;align-items:center;gap:.35rem;padding:.35rem .85rem;border-radius:99px;font-size:.85rem;font-weight:500;border:1px solid var(--edu-border);background:var(--edu-surface);color:var(--edu-ink);cursor:pointer;transition:all .2s}
.edu-chip:hover,.edu-chip.active{background:var(--edu-primary);border-color:var(--edu-primary);color:#fff}
.edu-lesson{display:flex;align-items:center;gap:.85rem;padding:.8rem 1rem;border:1px solid var(--edu-border);border-radius:14px;background:var(--edu-surface);transition:transform .2s var(--edu-ease),border-color .2s}
.edu-lesson:hover{transform:translateX(4px);border-color:var(--edu-primary)}
.edu-lesson.done .edu-lesson-ico{background:var(--edu-accent);color:#fff}
.edu-lesson-ico{width:36px;height:36px;border-radius:50%;display:grid;place-items:center;background:var(--edu-soft);color:var(--edu-primary);flex:none}
.edu-empty{text-align:center;padding:3rem 1rem;color:var(--edu-muted)}
.edu-empty i{font-size:3rem;opacity:.5}
.edu-step{counter-increment:s}
.edu-step::before{content:counter(s);display:grid;place-items:center;width:42px;height:42px;border-radius:50%;background:linear-gradient(135deg,#4f46e5,#6366f1);color:#fff;font-weight:700;margin-bottom:.75rem;box-shadow:0 6px 14px rgba(79,70,229,.3)}
.edu-cta{background:linear-gradient(135deg,#4338ca,#14b8a6);color:#fff;border-radius:24px;padding:3rem 1.5rem;box-shadow:var(--edu-shadow-lg)}
.edu-footer{background:var(--edu-surface);border-top:1px solid var(--edu-border);padding:1.5rem 0}

/* ===== Đăng nhập / đăng ký ===== */
.auth-wrap{min-height:100vh;display:grid;grid-template-columns:1fr 1fr}
.auth-side{background:linear-gradient(150deg,#312e81,#4f46e5 55%,#14b8a6);color:#fff;padding:3rem;display:flex;flex-direction:column;justify-content:space-between}
.auth-main{display:grid;place-items:center;padding:2rem 1rem}
.auth-card{width:100%;max-width:430px;animation:eduRise .5s var(--edu-ease) both}
@keyframes eduRise{from{opacity:0;translate:0 14px}to{opacity:1;translate:0 0}}
.auth-card .form-control{border-radius:11px;padding:.7rem .9rem;border-color:var(--edu-border)}
.auth-card .form-control:focus{border-color:var(--edu-primary);box-shadow:0 0 0 .2rem rgba(79,70,229,.15)}
.auth-card .input-group-text{background:var(--edu-surface);border-radius:11px 0 0 11px;border-color:var(--edu-border);color:var(--edu-muted)}
.auth-card .input-group .form-control{border-radius:0 11px 11px 0}
@media(max-width:860px){.auth-wrap{grid-template-columns:1fr}.auth-side{display:none}}

/* ===== Hiệu ứng khi cuộn (do edu.js bật) ===== */
.edu-reveal [data-reveal]{opacity:0;transform:translateY(22px);transition:opacity .65s var(--edu-ease),transform .65s var(--edu-ease);transition-delay:var(--d,0ms)}
.edu-reveal [data-reveal].is-in{opacity:1;transform:none}

/* ===== Skeleton: khung chờ khi đang tải dữ liệu =====
   Dùng: <div class="skeleton" style="height:120px"></div>  hoặc  .skeleton-text / .skeleton-circle */
.skeleton,.skeleton-text,.skeleton-circle{display:block;color:transparent!important;border-radius:10px;pointer-events:none;user-select:none;
  background:linear-gradient(90deg,var(--edu-skel-a) 25%,var(--edu-skel-b) 37%,var(--edu-skel-a) 63%);background-size:400% 100%;animation:eduShimmer 1.4s ease infinite}
.skeleton-text{height:1em;margin:.45em 0;border-radius:6px}
.skeleton-text.w-75{width:75%}.skeleton-text.w-50{width:50%}
.skeleton-circle{border-radius:50%;width:40px;height:40px}
@keyframes eduShimmer{0%{background-position:100% 50%}100%{background-position:0 50%}}

/* Nút đang xử lý: thêm thuộc tính data-loading vào nút submit */
.btn.is-loading{pointer-events:none;opacity:.85;position:relative;color:transparent!important}
.btn.is-loading::after{content:"";position:absolute;inset:0;margin:auto;width:1.1em;height:1.1em;border-radius:50%;border:2px solid rgba(255,255,255,.4);border-top-color:#fff;animation:eduSpin .7s linear infinite}
.btn-edu-ghost.is-loading::after,.btn-soft-primary.is-loading::after{border-color:rgba(79,70,229,.25);border-top-color:var(--edu-primary)}
@keyframes eduSpin{to{transform:rotate(360deg)}}

/* Nút lên đầu trang (đặt góc trái để không đè khung chat AI) */
.edu-top{position:fixed;left:18px;bottom:18px;width:44px;height:44px;border:1px solid var(--edu-border);border-radius:14px;display:grid;place-items:center;
  background:var(--edu-surface);color:var(--edu-primary);box-shadow:var(--edu-shadow-md);font-size:1.25rem;cursor:pointer;z-index:1020;
  opacity:0;visibility:hidden;translate:0 10px;transition:opacity .25s,translate .25s var(--edu-ease),visibility .25s,background-color .2s,color .2s}
.edu-top.show{opacity:1;visibility:visible;translate:0 0}
.edu-top:hover{background:var(--edu-primary);color:#fff}

/* ===== Velzon compat: class mà các trang edu_online còn dùng ===== */
.btn-soft-primary{--c:var(--bs-primary);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-primary:hover,.btn-soft-primary:focus,.btn-soft-primary:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-secondary{--c:var(--bs-secondary);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-secondary:hover,.btn-soft-secondary:focus,.btn-soft-secondary:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-success{--c:var(--bs-success);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-success:hover,.btn-soft-success:focus,.btn-soft-success:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-info{--c:var(--bs-info);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-info:hover,.btn-soft-info:focus,.btn-soft-info:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-warning{--c:var(--bs-warning);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-warning:hover,.btn-soft-warning:focus,.btn-soft-warning:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-danger{--c:var(--bs-danger);color:var(--c);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-danger:hover,.btn-soft-danger:focus,.btn-soft-danger:active{color:#fff!important;background:var(--c)!important;border-color:var(--c)!important}
.btn-soft-light{--c:var(--bs-light);color:var(--edu-ink);background:color-mix(in srgb,var(--c) 13%,transparent);border-color:transparent}
.btn-soft-light:hover,.btn-soft-light:focus,.btn-soft-light:active{color:var(--edu-ink)!important;background:var(--edu-soft-hover)!important;border-color:transparent!important}
.btn-icon{width:40px;height:40px;padding:0;display:inline-flex;align-items:center;justify-content:center}
.fs-11{font-size:11px!important}.fs-12{font-size:12px!important}.fs-13{font-size:13px!important}.fs-14{font-size:14px!important}.fs-15{font-size:15px!important}.fs-16{font-size:16px!important}
.progress-sm{height:5px}
.search-box{position:relative}.search-box .form-control{padding-left:2.4rem}.search-box .search-icon{position:absolute;left:.85rem;top:50%;transform:translateY(-50%);color:var(--edu-muted);pointer-events:none}

/* Tôn trọng người dùng tắt hiệu ứng chuyển động */
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important;scroll-behavior:auto!important}
  .edu-reveal [data-reveal]{opacity:1;transform:none}
}