/* =========================
   PAGE
========================= */

.theory-page{
    width:100%;
    max-width:1700px;
    margin:0 auto;

    height:100vh;

    display:flex;
    align-items:stretch;
    gap:18px;

    padding:16px 20px;

    background:
        linear-gradient(
            180deg,
            #f4f7ff 0%,
            #edf3ff 100%
        );

    overflow:hidden;
}

/* =========================
LEFT VIEWER
========================= */

.viewer{

    flex:1 1 auto;
    width:0;
    min-width:0;

    height:calc(100vh - 16px);

    display:flex;
    flex-direction:column;
    align-items:stretch;

    background:#fff;

    border:1px solid #e5ecff;
    border-radius:20px;

    box-shadow:
        0 10px 40px rgba(0,0,0,.06);

    overflow:hidden;

}

/* =========================
   VIEWER HEADER
========================= */

.viewer-header{

    height:52px;

    flex-shrink:0;

    display:flex;
    align-items:center;
    justify-content:space-between;

    padding:0 14px;

    background:
        linear-gradient(
            135deg,
            #ffffff,
            #f7faff
        );

    border-bottom:
        1px solid #e8eefc;
}

.top-btn{

    height:48px;

    padding:0 22px;

    border:none;

    border-radius:14px;

    font-size:15px;
    font-weight:700;

    color:white;

    cursor:pointer;

    background:
        linear-gradient(
            135deg,
        #3b82f6,
        #2563eb
        );

    box-shadow:
        0 10px 24px rgba(79,140,255,0.25);

    transition:0.2s;
}

.top-btn:hover{

    transform:translateY(-2px);

    background:
        linear-gradient(
            135deg,
        #3b82f6,
         #143e9b
        );

    color:white;

    box-shadow:
        0 8px 18px rgba(91,140,255,0.22);
}

.viewer-title{

    font-size:18px;
    font-weight:900;

    color:#0051ff;

    letter-spacing:-0.5px;
}

/* =========================
   VIEWER CONTENT
========================= */

/* =========================
   VIEWER CONTENT (FIXED HEIGHT)
========================= */

/* =========================
   VIEWER CONTENT (Mở rộng tối đa không gian)
========================= */

.viewer-box {
    position: relative;
    background: linear-gradient(135deg, #f8fbff 0%, #eef4ff 100%);
    border-radius: 18px;
    border: 1px solid #e6eeff;
    box-shadow: 0 8px 24px rgba(0,0,0,0.04);
    
    flex: 1;
    min-height: 0;
    overflow-y: auto;
    overflow-x: hidden;
    display: block; 
    padding: 12px; /* Thu nhỏ padding viền một chút để diện tích hiển thị bên trong rộng hơn */
}

/* Các thành phần nội dung bên trong (iframe, placeholder, v.v.) được nới rộng tối đa */
.viewer-box iframe,
.viewer-placeholder {
    min-height: 780px !important; /* 🔥 Tăng chiều cao tối thiểu của vùng chứa tài liệu lên (mặc định cũ thường là 650px - 700px) */
    width: 100%;
    box-sizing: border-box;
}

.material-extra-list-wrapper {
    width: 100%;
    margin-top: 24px;
    margin-bottom: 30px; 
    display: block;
    clear: both;
}
.viewer-placeholder{

    width:100%;
    height:100%;

    display:flex;
    align-items:center;
    justify-content:center;

    text-align:center;

    border-radius:16px;

    background:white;

    border:2px dashed #d9e4ff;

    color:#7d8db3;

    font-size:16px;
    font-weight:700;
}


/* =========================
   RIGHT MENU
========================= */

.menu{

    width:320px;

    flex-shrink:0;

    display:flex;
    flex-direction:column;

    gap:18px;

    padding:22px;

    overflow-y:auto;

    background:white;

    border-radius:26px;

    border:1px solid #e5ecff;

    box-shadow:
        0 12px 40px rgba(0,0,0,0.06);
}

/* =========================
   HERO
========================= */

.hero-mini{

    font-size:18px;
    font-weight:900;

    color:#14213d;

    letter-spacing:-0.6px;
}

/* =========================
   UPLOAD BOX
========================= */

.upload-box,
.lesson-panel{

    padding:16px;

    border-radius:20px;

    background:
        linear-gradient(
            180deg,
            #f8fbff,
            #eef4ff
        );

    border:1px solid #dce7ff;
}

.upload-form{

    display:flex;
    gap:6px;
    flex-direction:column;
}

.file-picker input{

    display:none;
}

.file-ui{

    height:30px;

    border-radius:14px;

    display:flex;
    align-items:center;
    justify-content:center;

    background:white;

    border:2px dashed #c9d9ff;

    cursor:pointer;

    font-size:14px;

    font-weight:700;

    color:#4566b0;
}

.upload-btn{

    height:40px;

    min-width:160px;

    margin:10px auto 0 auto;

    display:flex;

    align-items:center;
    justify-content:center;

    border:none;

    border-radius:14px;

    cursor:pointer;

    font-size:13px;
    font-weight:800;

    color:white;

    background:
        linear-gradient(
            135deg,
        #3b82f6,
        #2563eb
        );

    box-shadow:
        0 10px 24px rgba(79,140,255,0.25);

    transition:0.2s;
}

.upload-btn:hover{

    transform:translateY(-2px);
}

/* =========================
   FORM
========================= */
.file-select-box{

    display:flex;

    flex-direction:column;

    gap:10px;

    margin-bottom:16px;
}

/* =========================
   LABEL
========================= */

.file-select-box label,
.lesson-panel label{

    display:flex;
    align-items:center;

    font-size:14px;
    font-weight:700;

    color:#34415f;

    letter-spacing:0.2px;
}

.material-upload-box{

    display:flex;

    flex-direction:column;

    gap:10px;

    margin-bottom:16px;
}

.material-upload-box label{

    display:flex;
    align-items:center;

    font-size:14px;
    font-weight:700;

    color:#34415f;

    letter-spacing:0.2px;
}

.material-file-input{

    width:100%;

    height:40px;

    padding:0 14px;

    border-radius:16px;

    font-size:14px;
    font-weight:500;

    color:#24324d;

    display:flex;
    align-items:center;

    cursor:pointer;

    outline:none;

}

.material-file-input:hover{

    border-color:#bfd1ff;
}

.material-file-input:focus{

    border-color:#5b8cff;

    box-shadow:
        0 0 0 4px rgba(91,140,255,0.12);

    transform:translateY(-1px);
}

.material-file-input::file-selector-button{

    height:40px;

    padding:0 18px;

    margin-right:14px;

    border:none;

    border-radius:12px;

    background:
        linear-gradient(
            135deg,
        #3b82f6,
        #2563eb
        );

    color:white;

    font-size:13px;
    font-weight:700;

    cursor:pointer;

    transition:0.2s;

    box-shadow:
        0 6px 14px rgba(91,140,255,0.22);
}

.material-file-input::file-selector-button:hover{

    transform:translateY(-1px);

    opacity:0.96;
}

/* =========================
   INPUT + SELECT
========================= */

.file-dropdown,
.file-input{

    width:100%;

    height:40px;

    padding:0 16px;

    border-radius:16px;

    border:1px solid #d7e2ff;

    background:white;

    font-size:14px;
    font-weight:500;

    color:#24324d;

    outline:none;

    transition:
        border-color 0.2s,
        box-shadow 0.2s,
        transform 0.15s;

    box-shadow:
        0 2px 8px rgba(20,33,61,0.03);
}

/* =========================
   SELECT
========================= */

.file-dropdown{

    cursor:pointer;

    appearance:none;

    background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='18' height='18' fill='%237b8bb7' viewBox='0 0 16 16'%3E%3Cpath d='M1.5 5.5l6 6 6-6' stroke='%237b8bb7' stroke-width='2' fill='none' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");

    background-repeat:no-repeat;

    background-position:right 16px center;

    padding-right:48px;
}

/* =========================
   FILE INPUT
========================= */

.file-input{

    display:flex;

    align-items:center;

    cursor:pointer;

    padding:0 14px;
}

/* BUTTON */

.file-input::file-selector-button{

    height:40px;

    padding:0 18px;

    margin-right:14px;

    border:none;

    border-radius:12px;

    background:
        linear-gradient(
            135deg,
        #3b82f6,
        #2563eb
        );

    color:white;

    font-size:13px;
    font-weight:700;

    cursor:pointer;

    transition:0.2s;

    box-shadow:
        0 6px 14px rgba(91,140,255,0.22);
}

.file-input::file-selector-button:hover{

    transform:translateY(-1px);

    opacity:0.96;
}

/* =========================
   FOCUS
========================= */

.file-dropdown:focus,
.file-input:focus{

    border-color:#5b8cff;

    box-shadow:
        0 0 0 4px rgba(91,140,255,0.12);

    transform:translateY(-1px);
}

/* =========================
   HOVER
========================= */

.file-dropdown:hover,
.file-input:hover{

    border-color:#bfd1ff;
}
/* =========================
   CLASS BAR
========================= */

.class-bar{

    display:flex;
    gap:10px;

    flex-wrap:wrap;
}

.cbtn{

    height:42px;

    padding:0 18px;

    border:none;

    border-radius:12px;

    cursor:pointer;

    font-size:14px;
    font-weight:800;

    background:#edf3ff;

    color:#4c5f8c;

    transition:0.2s;
}

.cbtn.active{

    color:white;

    background:
        linear-gradient(
            135deg,
        #f59e0b,
        #d97706
        );

    box-shadow:
        0 8px 20px rgba(79,140,255,0.22);
}

/* =========================
   CLASS BOX
========================= */

.class-box{

    display:flex;
    flex-direction:column;

    gap:18px;
}

.hidden{

    display:none;
}

/* =========================
   TOPIC
========================= */

.topic{

    padding:18px;

    border-radius:20px;

    background:
        linear-gradient(
            180deg,
            #fbfcff,
            #f4f7ff
        );

    border:1px solid #e4ebff;
}

.topic-title{

    margin-bottom:14px;

    font-size:15px;
    font-weight:900;

    color:#14213d;
}

/* =========================
   LESSON
========================= */

.lesson{

    margin-bottom:10px;

    padding:14px 16px;

    border-radius:14px;

    cursor:pointer;

    transition:0.2s;

    background:white;

    border:1px solid #edf2ff;
}

.lesson:hover{

    transform:translateY(-2px);

    border-color:#bfd1ff;

    box-shadow:
        0 10px 20px rgba(0,0,0,0.05);
}

.lesson .name{

    font-size:14px;
    font-weight:700;

    line-height:1.5;

    color:#2a3655;
}

/* =========================
   IFRAME
========================= */

.lesson-frame{

    width:100%;

    flex:1;

    min-height:700px;

    border:none;

    border-radius:18px;

    background:white;
}

/* =========================
   SCROLLBAR
========================= */

.menu::-webkit-scrollbar{

    width:8px;
}

.menu::-webkit-scrollbar-thumb{

    background:#cfdcff;

    border-radius:20px;
}
/* =========================
   LESSON ITEM
========================= */

.lesson{

    position:relative;

    padding:14px 16px;

    margin-bottom:10px;

    border-radius:16px;

    cursor:pointer;

    background:white;

    border:1px solid #e6ecff;

    transition:
        transform 0.18s,
        box-shadow 0.18s,
        border-color 0.18s,
        background 0.18s;

    box-shadow:
        0 2px 10px rgba(20,33,61,0.03);
}

/* HOVER */

.lesson:hover{

    transform:translateY(-2px);

    border-color:#bfd1ff;

    background:#f7faff;

    box-shadow:
        0 8px 20px rgba(91,140,255,0.08);
}

/* ACTIVE */

.active-lesson{

    background:
        linear-gradient(
            135deg,
            #fffdf8,
            #ffd753
        );

    border-color:transparent;

    box-shadow:
        0 12px 28px rgba(91,140,255,0.22);
}

/* TEXT ACTIVE */

.active-lesson .name{

    color:white;
}

/* LEFT GLOW */

.active-lesson::before{

    content:"";

    position:absolute;

    left:0;
    top:10px;
    bottom:10px;

    width:5px;

    border-radius:20px;

    background:white;

    opacity:0.9;
}

/* NAME */

.lesson .name{

    font-size:14px;

    font-weight:700;

    color:#24324d;

    line-height:1.45;

    transition:0.18s;
}

/* =========================
   THEORY HERO
========================= */

.theory-hero{

    width:calc(100% - 48px);

    margin:12px auto 6px auto;

    min-height:56px;

    padding:8px 18px;

    border-radius:28px;

    display:flex;

    align-items:center;

    justify-content:space-between;

    gap:14px;

    overflow:hidden;

    background:
        linear-gradient(
            135deg,
            #08122f 0%,
            #19377c 55%,
            #2d63e3 100%
        );
}

/* =========================
   LEFT
========================= */

.theory-hero .hero-left{

    flex:1;

    display:flex;

    justify-content:flex-start;

    min-width:0;

    margin-top:6px;
}

/* =========================
   HERO BADGE
========================= */

.theory-hero .hero-badge{

    display:flex;

    align-items:center;

    gap:8px;

    min-height:50px;

    padding:7px 16px 7px 10px;

    border-radius:999px;

    background:
        rgba(255,255,255,0.10);

    border:
        1px solid rgba(255,255,255,0.08);

    backdrop-filter:blur(8px);

    width:fit-content;

    max-width:760px;
}

/* =========================
   LOGO WRAP
========================= */

.theory-hero .hero-badge-logo{

    width:40px;
    height:40px;

    flex-shrink:0;

    display:flex;

    align-items:center;
    justify-content:center;
}

/* =========================
   LOGO
========================= */

.theory-hero .hero-logo{

    width:100%;
    height:100%;

    object-fit:contain;

    display:block;
}

/* =========================
   TEXT WRAP
========================= */

.theory-hero .hero-badge-text{

    display:flex;

    flex-direction:column;

    justify-content:center;

    min-width:0;
}

/* =========================
   TITLE
========================= */

.theory-hero .hero-badge-title{

    margin: 0 0 4px 0;

    font-size:16px;

    font-weight:900;

    line-height:1.02;

    letter-spacing:-0.2px;

    color:white;

    white-space:nowrap;
}

/* =========================
   SUB TITLE
========================= */

.theory-hero .hero-badge-sub{

    margin-top:1px;

    font-size:12px;

    font-weight:700;

    line-height:1.05;

    letter-spacing:0.3px;

    color:rgba(255,255,255,0.72);

    white-space:nowrap;
}

/* =========================
   RIGHT
========================= */

.theory-hero .hero-right-layout{

    display:flex;

    align-items:center;

    flex-shrink:0;
}

/* =========================
   USER CARD
========================= */

.theory-hero .user-card{

    width:auto;

    padding:6px 12px;

    border-radius:16px;

    background:
        rgba(255,255,255,0.10);

    border:
        1px solid rgba(255,255,255,0.08);

    backdrop-filter:blur(8px);
}

/* =========================
   CARD TOP
========================= */

.theory-hero .user-card-top{

    display:flex;

    align-items:center;

    gap:8px;
}

/* =========================
   AVATAR
========================= */

.theory-hero .user-avatar{

    width:32px;
    height:32px;

    border-radius:10px;

    flex-shrink:0;

    display:flex;

    align-items:center;
    justify-content:center;

    font-size:15px;
    font-weight:800;

    color:white;

    background:
        linear-gradient(
            135deg,
            #60a5fa,
            #2563eb
        );
}

/* =========================
   USER INFO
========================= */

.theory-hero .user-card-info{

    display:flex;

    flex-direction:column;

    justify-content:center;

    gap:0;

    line-height:1;
}

/* HELLO */

.theory-hero .user-hello{

    margin:1px;

    font-size:15px;

    color:rgba(255,255,255,0.72);
}

/* NAME */

.theory-hero .user-name{

    margin:1px;

    font-size:14px;

    font-weight:800;

    line-height:1.05;

    color:white;

    white-space:nowrap;
}

/* META */

.theory-hero .user-meta{

    margin:1px;

    font-size:13px;

    line-height:1.05;

    color:rgba(255,255,255,0.78);

    white-space:nowrap;
}

/* =========================
   RIGHT LAYOUT
========================= */

.theory-hero .hero-right-layout{

    display:flex;

    align-items:center;

    gap:10px;

    flex-shrink:0;
}

/* =========================
   EXIT BUTTON
========================= */

.hero-exit-btn{

    height:44px;

    padding:0 16px;

    border:none;

    border-radius:16px;

    display:flex;

    align-items:center;

    gap:8px;

    cursor:pointer;

    background:
        rgba(255,255,255,0.10);

    border:
        1px solid rgba(255,255,255,0.08);

    backdrop-filter:blur(8px);

    color:white;

    font-size:13px;

    font-weight:800;

    transition:
        transform 0.18s,
        background 0.18s,
        border-color 0.18s;
}

/* HOVER */

.hero-exit-btn:hover{

    transform:translateY(-2px);

    background:
        rgba(255,255,255,0.16);

    border-color:
        rgba(255,255,255,0.18);
}

/* ICON */

.hero-exit-btn .exit-icon{

    font-size:16px;

    line-height:1;
}

/* TEXT */

.hero-exit-btn .exit-text{

    white-space:nowrap;
}
/* =========================
   ACTIVE LESSON
========================= */

.lesson{

    position:relative;

    transition:
        all .25s ease;

    border-radius:14px;

    cursor:pointer;
}

/* hover */

.lesson:hover{

    background:rgba(0, 0, 0, 0.06);

    transform:translateX(4px);
}

/* active */

.lesson.active-lesson{

    background:#fff3e6;

    border:1px solid #ffb15e;

    border-left:5px solid #ff8a00;

    transform:translateX(4px);

    box-shadow:
        0 6px 18px rgba(255,138,0,0.12);
}

/* title active */

.lesson.active-lesson .name{

    color:#c66300;

    font-weight:700;
}

.viewer-title{

    display:flex;

    align-items:center;

    gap:10px;

    line-height:1.3;
    
    font-size:18px;

    font-weight:900;

    color:#14213d;

    letter-spacing:-0.6px;
}
.current-lesson-name{

    line-height:1.3;
    
    font-size:18px;
    
    font-weight:900;

    color:#c66300;

    letter-spacing:-0.6px;
     
    margin-right:auto;
}

.doc-dots{
    display:flex;
    align-items:center;
    gap:5px;
    margin-right:9px;
}

.doc-dots span{

    width:12px;
    height:12px;

    border-radius:50%;

    animation:dotFloat 1.8s ease-in-out infinite;

    box-shadow:
        0 0 12px rgba(25,70,160,0.22);
}

/* xanh đậm → nhạt */
.doc-dots span:nth-child(1){
    background:#123a88;
}

.doc-dots span:nth-child(2){
    background:#3f6ed8;
    animation-delay:.2s;
}

.doc-dots span:nth-child(3){
    background:#8fb2ff;
    animation-delay:.4s;
}

/* =========================
   EXTRA FILES
========================= */

.material-extra-list{

    width:260px;

    min-width:260px;

    background:#fff;

    border-radius:20px;

    padding:18px;

    border:1px solid #e5e7eb;

    overflow:auto;
}

.extra-title{

    font-size:18px;

    font-weight:700;

    margin-bottom:16px;
    
}

.extra-file{

    margin-bottom:10px;
}

.extra-file-btn{

    width:100%;

    border:none;

    background:#f3f4f6;

    border-radius:12px;

    padding:12px;

    text-align:left;

    cursor:pointer;

    transition:.2s;
}

.extra-file-btn:hover{

    background:#e5e7eb;
}

.empty-files{

    color:#888;

    font-size:14px;
}
/* =========================
   VIEWER FIX
========================= */


.viewer{

    flex:1;
    display:flex;
    flex-direction:column;

    height:100%;

    overflow:hidden;

    padding-right:0;

}

/* =========================
   EXTRA WRAPPER
========================= */

.material-extra-list-wrapper{

    width:100%;

    margin-top:18px;
}

/* =========================
   EXTRA FILES
========================= */
.material-extra-list {
    width: 100%;
    background: transparent;           /* 🔥 Bỏ nền trắng, chuyển thành trong suốt */
    border: none;                      /* 🔥 Tuyệt đối không có viền ngoài */
    border-radius: 0;                  /* 🔥 Bỏ bo góc */
    box-shadow: none;                  /* 🔥 Bỏ hiệu ứng đổ bóng */
    padding: 10px 15px;                 /* 🔥 Thu gọn khoảng đệm cho sát lề tự nhiên */
    margin-left: 10;
    margin-top: 4px;
    box-sizing: border-box;
}

/* Tinh chỉnh riêng phần tiêu đề bên trong cho đẹp */
.material-extra-list .extra-title {
    font-size: 16px;
    font-weight: 800;
    color: #1e293b;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
    letter-spacing: -0.3px;
}

/* Tinh chỉnh phần chữ "Không có tài liệu khác" */
.material-extra-list .empty-files {
    color: #94a3b8;
    font-size: 13px;
    font-weight: 500;
    font-style: italic;
}
/* =========================
   FILE LIST
========================= */

#extraFiles{

    display:flex;

    flex-wrap:wrap;

    gap:12px;
}

.extra-title{

    display:flex;
    flex-wrap:wrap;
    gap:8px;   /* 🔥 giảm 12 → 8 */
}

/* =========================
   FILE ITEM (GỌN LẠI)
========================= */

.extra-file-btn{
    padding:6px 10px;
    font-size:12px;
    border-radius:999px;
}

.extra-file-btn:hover{

    background:#e5e7eb;
}

.empty-files{

    color:#888;

    font-size:14px;
}

.hero-exit-btn{
    position: relative;
    z-index: 9999;   /* 🔥 luôn nằm trên cùng */
    pointer-events: auto;
}
.hero-glow{
    pointer-events: none; /* 🔥 quan trọng */
}
.hero-section{
    position: relative;
    z-index: 1;
}
.hero-exit-btn *{
    pointer-events: none;
}


.viewer-box{

    position:relative;

    background:
        linear-gradient(135deg, #f8fbff 0%, #eef4ff 100%);

    border-radius:18px;

    border:1px solid #e6eeff;

    box-shadow:
        0 8px 24px rgba(0,0,0,0.04);

    flex:1;

    overflow:auto;
}

/* =========================
   PLACEHOLDER CENTER CARD
========================= */

.viewer-placeholder{

    width:100%;

    min-height:700px;

    display:flex;
    align-items:center;
    justify-content:center;

    padding:20px;

    text-align:center;
}

.viewer-placeholder{
    display:flex;
    flex-direction:column;
    align-items:center;
    justify-content:flex-start;

    color:#6b7aa6;
    font-size:16px;
    font-weight:600;
    line-height:1.6;

    background:rgba(255,255,255,0.6);
    backdrop-filter:blur(6px);

    border:1px solid #dbe7ff;
    border-radius:16px;

    margin:20px;
    padding:10px 20px 30px;
}

.viewer-placeholder::before{
    content:"📖";

    font-size:42px;
    display:block;

    margin-bottom:8px;

    animation:floatIcon 2.5s ease-in-out infinite;
}

.viewer-placeholder .text{
    margin:0;
    padding:0;
}

.file-picker{
    position:relative;
    display:inline-block;
    cursor:pointer;
}

/* tooltip */
.file-picker::after{
    content:attr(data-tooltip);

    position:absolute;
    bottom:calc(100% + 12px);
    left:50%;
    transform:translateX(-50%);

    background:#3f6ed8;
    color:#fff;

    padding:10px 14px;
    border-radius:12px;

    font-size:12px;
    line-height:1.5;
    white-space:nowrap;

    opacity:0;
    visibility:hidden;

    transition:.25s ease;

    box-shadow:0 10px 30px rgba(0,0,0,.25);

    z-index:100;
}

/* mũi tên */
.file-picker::before{
    content:"";

    position:absolute;
    bottom:100%;
    left:50%;
    transform:translateX(-50%);

    border:7px solid transparent;
    border-top-color:#1e293b;

    opacity:0;
    visibility:hidden;

    transition:.25s ease;
}

/* hover hiện tooltip */
.file-picker:hover::after,
.file-picker:hover::before{
    opacity:1;
    visibility:visible;
}

.material-upload-box{
    position:relative;
}

/* tooltip */
.material-upload-box::after{
    content:attr(data-tooltip);

    position:absolute;
    bottom:calc(100% + 14px);
    left:50%;
    transform:translateX(-50%);

    background:#3f6ed8;
    color:#fff;

    padding:11px 15px;
    border-radius:14px;

    font-size:12px;
    line-height:1.5;

    white-space:nowrap;

    opacity:0;
    visibility:hidden;

    transition:.25s ease;

    box-shadow:0 12px 30px rgba(0,0,0,.28);

    z-index:1000;
}

/* mũi tên */
.material-upload-box::before{
    content:"";

    position:absolute;
    bottom:100%;
    left:50%;
    transform:translateX(-50%);

    border:7px solid transparent;
    border-top-color:#0f172a;

    opacity:0;
    visibility:hidden;

    transition:.25s ease;

    z-index:1000;
}

/* hover */
.material-upload-box:hover::after,
.material-upload-box:hover::before{
    opacity:1;
    visibility:visible;
}


/* ==================================================
   MOBILE THEORY PAGE - OPTIMIZED FOR MOBILE SPATIAL DESIGN
================================================== */

@media (max-width: 768px) {

  /* =========================
     GLOBAL & PAGE LAYOUT
  ========================= */
  html {
    font-size: 14px; /* Giảm nhẹ base font để các thành phần co giãn cân đối hơn */
  }

  .theory-page {
    width: 100%;
    max-width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    gap: 8px;       /* Thu gọn khoảng cách giữa các khối chính */
    padding: 6px;   /* Tiết kiệm diện tích viền màn hình di động */
    overflow: visible;
  }

  /* =========================
     VIEWER & HEADER SECTION
  ========================= */
  .viewer {
    width: 100%;
    min-width: 100%;
    min-height: auto;
    border-radius: 12px;
    order: 1;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
  }

  .viewer-header {
    padding: 10px 12px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    align-items: stretch;
    background: #fff;
    position: sticky;
    top: 0;
    z-index: 20;
    border-bottom: 1px solid #edf2f7;
    border-radius: 12px 12px 0 0;
  }

  .doc-dots span{

    width:5px;
    height:5px;
}
  .viewer-title {
    font-size: 14px;
    font-weight: 700;
    text-align: center;
    line-height: 1.35;
    color: #1e293b;
    display: -webkit-box;
    -webkit-line-clamp: 2; /* Giới hạn tối đa 2 dòng tránh chiếm chỗ */
    -webkit-box-orient: vertical;
    overflow: hidden;
  }

  /* Gom nhóm cụm nút bấm header thành 2 cột gọn gàng */
  .viewer-header > div {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 6px;
    width: 100%;
  }

  .top-btn {
    width: 100%;
    height: 36px;
    padding: 0 8px;
    border-radius: 8px;
    font-size: 11.5px;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

/* =========================
     VIEWER CONTENT & IFRAME
  ========================= */
.viewer-box {

    min-height: 0 !important;

    height: auto !important;

    padding: 4px;

    background: #f8fafc;

    border-radius: 0 0 12px 12px;

    display: flex;

    flex-direction: column;

    overflow-x: hidden;

    overflow-y: auto;

}

/* =========================
   PDF VIEWER - MOBILE
========================= */

.lesson-frame {
    width: 100% !important;

    height: calc(100vh - 180px) !important;

    min-height: 500px !important;

    max-height: none !important;

    display: block;

    border: none !important;

    border-radius: 8px;

    background: #fff;

    overflow: auto !important;

    -webkit-overflow-scrolling: touch;
}

  .viewer-placeholder {
    min-height: 280px;
    padding: 20px 12px;
    font-size: 13px;
    line-height: 1.5;
    text-align: center;
  }

  /* =========================
     SLIDE-OUT MENU & PANELS
  ========================= */
  .mobile-menu-btn {
    position: fixed;
    left: 10px;
    top: 10px;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: 10px;
    background: #2563eb;
    color: #fff;
    font-size: 20px;
    font-weight: 700;
    z-index: 3000;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
  }

  .menu {
    position: fixed;
    left: -300px;
    top: 0;
    width: 280px; /* Thu hẹp độ rộng drawer menu vừa vặn màn hình nhỏ */
    height: 100vh;
    max-height: none;
    overflow-y: auto;
    overflow-x: hidden;
    -webkit-overflow-scrolling: touch;
    z-index: 2500;
    transition: left 0.25s ease-in-out;
    border-radius: 0;
    padding: 12px;
    gap: 10px;
    background: #fff;
    box-shadow: 4px 0 20px rgba(0, 0, 0, 0.1);
  }

  .menu.show {
    left: 0;
  }

  .menu-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    opacity: 0;
    visibility: hidden;
    transition: 0.2s ease-in-out;
    z-index: 2400;
  }

  .menu-overlay.show {
    opacity: 1;
    visibility: visible;
  }

  .hero-mini {
    font-size: 15px;
    font-weight: 700;
    text-align: center;
    letter-spacing: -0.2px;
    margin-bottom: 4px;
  }

  /* =========================
     CARDS, UPLOAD & FORMS
  ========================= */
  .upload-box,
  .lesson-panel {
    padding: 10px;
    border-radius: 12px;
    margin-bottom: 6px;
    background: #f8fafc;
    border: 1px solid #f1f5f9;
  }

  .upload-form {
    gap: 8px;
  }

  .file-select-box,
  .material-upload-box {
    gap: 6px;
    margin-bottom: 8px;
  }

  .file-select-box label,
  .lesson-panel label,
  .material-upload-box label {
    font-size: 12px;
    font-weight: 600;
  }

  .file-ui,
  .file-dropdown,
  .file-input,
  .material-file-input {
    height: 36px;
    font-size: 11.5px;
    border-radius: 8px;
    padding-left: 10px;
    padding-right: 10px;
  }

  .file-input::file-selector-button,
  .material-file-input::file-selector-button {
    height: 28px;
    padding: 0 8px;
    margin-right: 8px;
    border-radius: 6px;
    font-size: 11px;
  }

  .file-dropdown {
    background-position: right 10px center;
    padding-right: 32px;
  }

  .upload-btn {
    width: 100%;
    min-width: 0;
    height: 36px;
    margin-top: 4px;
    font-size: 12px;
    font-weight: 600;
    border-radius: 8px;
  }

  /* =========================
     CLASS BAR & BUTTONS
  ========================= */
  .class-bar {
    gap: 6px;
  }

  .cbtn {
    flex: 1;
    min-width: 75px;
    height: 34px;
    padding: 0 8px;
    font-size: 11.5px;
    font-weight: 600;
    border-radius: 8px;
  }

  /* =========================
     TOPICS & LESSONS LIST
  ========================= */
  .class-box {
    gap: 8px;
  }

  .topic {
    padding: 10px;
    border-radius: 12px;
    margin-bottom: 6px;
    background: #f8fafc;
    border: 1px solid #f1f5f9;
    overflow: hidden;
  }

  .topic-title {
    margin-bottom: 6px;
    font-size: 12.5px;
    font-weight: 700;
    line-height: 1.35;
    color: #334155;
  }

  .lesson {
    margin-bottom: 6px;
    padding: 8px 10px;
    border-radius: 8px;
    background: #fff;
    border: 1px solid #e2e8f0;
    transition: background 0.15s, border-color 0.15s;
  }

  .lesson:active {
    transform: scale(0.98);
    background: #eff6ff;
    border-color: #93c5fd;
  }

  .lesson .name {
    font-size: 11.5px;
    line-height: 1.4;
    word-break: break-word;
    overflow-wrap: anywhere;
    color: #475569;
  }

  /* =========================
     EXTRA MATERIALS LIST
  ========================= */
  .material-extra-list-wrapper {
    margin-top: 8px;
    margin-bottom: 10px;
    padding: 0;
  }

  .material-extra-list {
    width: 100%;
    background: transparent;
    border: none;
    box-shadow: none;
    padding: 4px 10px;
    margin: 4px 0 0 0;
  }

  .material-extra-list .extra-title {
    font-size: 13px;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 6px;
    gap: 6px;
  }

  .material-extra-list .empty-files {
    color: #94a3b8;
    font-size: 11.5px;
  }

  /* =========================
     SCROLLBAR & UTILS
  ========================= */
  .menu::-webkit-scrollbar {
    width: 4px;
  }

  .menu::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 10px;
  }

  * {
    -webkit-tap-highlight-color: transparent;
  }
}

/* ==================================================
   EXTRA SMALL PHONES (<= 390px)
================================================== */
@media (max-width: 390px) {
  .theory-page {
    padding: 4px;
    gap: 6px;
  }

  .viewer-title {
    font-size: 13px;
  }

  .top-btn,
  .upload-btn {
    height: 34px;
    font-size: 11px;
  }

  .cbtn {
    min-width: 70px;
    height: 32px;
    font-size: 11px;
  }

  .lesson-frame {
    height: 55vh;
    min-height: 300px;
  }
}

/* ==================================================
   LANDSCAPE PHONE OPTIMIZATION
================================================== */
@media (max-width: 900px) and (orientation: landscape) {
  .viewer {
    min-height: 90vh;
  }
  .lesson-frame {
    height: 80vh;
    min-height: 280px;
  }
}

/* ==================================================
   DESKTOP RESET (>= 769px)
================================================== */
@media (min-width: 769px) {
  .mobile-menu-btn,
  .menu-overlay {
    display: none;
  }
}

/* ==================================================
   FIX GIAO DIỆN VIEWER-TITLE CHO MOBILE
================================================== */

@media (max-width: 768px) {

  /* 1. Đảm bảo khung chứa header sắp xếp linh hoạt theo chiều dọc hoặc ngang hợp lý */
  .viewer-header {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 12px;
    gap: 8px;
  }

  /* 2. Ép .viewer-title thành một khối hiển thị ngang (row), sát lề trái, không bị tách đôi */
  .viewer-title {
    display: flex !important;
    flex-direction: row !important;
    align-items: center !important;
    justify-content: flex-start !important;
    gap: 8px !important;                 /* Khoảng cách giữa 3 chấm và tên bài học */
    width: 100% !important;
    max-width: 100% !important;
    margin: 0 !important;
    padding: 0 !important;
    text-align: left !important;
  }

  /* 3. Thu nhỏ cụm 3 dấu chấm và ép sát lề trái */
  .doc-dots {
    display: flex !important;
    align-items: center !important;
    gap: 3px !important;
    margin: 0 !important;
    flex-shrink: 0 !important;           /* Không cho co giãn hay bị bóp méo */
  }

  .doc-dots span {
    width: 8px !important;
    height: 8px !important;
    border-radius: 50% !important;
  }

  /* 4. Tên bài học thu nhỏ, tự động co giãn và tràn dòng hợp lý */
  .current-lesson-name {
    font-size: 14px !important;
    font-weight: 800 !important;
    line-height: 1.35 !important;
    color: #c66300 !important;
    letter-spacing: -0.2px !important;
    
    margin: 0 !important;
    padding: 0 !important;
    text-align: left !important;
    
    flex: 1 !important;                  /* Chiếm phần không gian còn lại trên hàng */
    width: auto !important;
    max-width: 100% !important;
    overflow-wrap: anywhere !important;
    word-break: break-word !important;
  }

}

/* Tối ưu riêng cho điện thoại rất nhỏ (<= 390px) */
@media (max-width: 390px) {
  .current-lesson-name {
    font-size: 13px !important;
  }
  .doc-dots span {
    width: 7px !important;
    height: 7px !important;
  }
}


/* ==================================================
   MOBILE OPTIMIZATION: HERO HEADER & BACK BUTTON
================================================== */

@media (max-width: 768px) {

  /* 1. Đổi khung chứa bên phải thành dạng hàng ngang (row) và căn giữa */
  .hero-right-layout {
    display: flex !important;
    flex-direction: row !important;
    align-items: stretch !important;
    gap: 8px !important;
    width: 100% !important;
  }

  /* 2. Thu gọn thẻ user card để chia sẻ không gian với nút */
  .user-card {
    flex: 1 !important;              /* Tự động co giãn chiếm phần lớn không gian */
    min-width: 0 !important;         /* Tránh bị tràn chữ bên trong flexbox */
    margin-bottom: 0 !important;
    padding: 10px 12px !important;
    border-radius: 12px !important;
  }

  /* Tinh chỉnh cỡ chữ bên trong user card cho gọn gàng trên mobile */
  .user-card .user-name {
    font-size: 13.5px !important;
    font-weight: 700 !important;
  }
  
  .user-card .user-hello,
  .user-card .user-meta {
    font-size: 11px !important;
  }

  .user-card .user-avatar {
    width: 34px !important;
    height: 34px !important;
    font-size: 14px !important;
  }

  /* 3. Tối ưu nút "Quay lại" nằm gọn bên cạnh user card */
  .hero-exit-btn {
    flex-shrink: 0 !important;       /* Cố định kích thước, không bị bóp méo */
    width: auto !important;
    height: auto !important;
    min-height: unset !important;
    padding: 0 14px !important;
    margin: 0 !important;
    border-radius: 12px !important;
    display: flex !important;
    flex-direction: column !important; /* Xếp icon lên trên, chữ "Quay lại" xuống dưới cho gọn chiều ngang */
    align-items: center !important;
    justify-content: center !important;
    gap: 2px !important;
    font-size: 11px !important;
    font-weight: 600 !important;
    white-space: nowrap !important;
  }

  .hero-exit-btn .exit-icon {
    font-size: 14px !important;
    line-height: 1 !important;
  }

}

/* Tối ưu riêng cho điện thoại rất nhỏ (<= 390px) */
@media (max-width: 390px) {
  .hero-right-layout {
    gap: 6px !important;
  }
  
  .hero-exit-btn {
    padding: 0 10px !important;
    font-size: 10.5px !important;
  }
  
  .user-card {
    padding: 8px 10px !important;
  }
}
/* =================================================
   MOBILE - VIEWER HEADER COMPACT
================================================= */

@media (max-width:768px){

    .viewer-header{

        height:42px;

        flex-shrink:0;

        display:flex;
        align-items:center;
        justify-content:space-between;

        padding:12px 10px;

        background:
            linear-gradient(
                135deg,
                #ffffff,
                #f7faff
            );

        border-bottom:
            1px solid #e8eefc;

    }


    .viewer-title{

        font-size:14px;

        font-weight:800;

        letter-spacing:-0.3px;

        white-space:nowrap;

        overflow:hidden;

        text-overflow:ellipsis;

    }


    .viewer-header .top-btn{

        height:34px;

        padding:0 12px;

        border-radius:10px;

        font-size:12px;

    }

}

/* =====================================================
THEORY HERO MOBILE - LOGO BALANCE FIX (BIGGER)
===================================================== */

@media(max-width:768px){

/* =========================
THEORY HERO MOBILE
========================= */

.theory-hero{

    width:calc(100% - 16px);

    margin:8px auto 6px auto;

    min-height:52px;

    padding:7px 12px;

    border-radius:24px;

    gap:12px;

}



/* =========================
BADGE MOBILE
========================= */

.theory-hero .hero-badge{

    min-height:46px;

    height:46px;

padding:6px 14px 6px 6px;   

    gap:6px;

    border-radius:999px;

    max-width:100%;

}

.theory-hero .hero-badge-text{

    transform:translateX(-2px);

}

/* =========================
LOGO WRAPPER MOBILE
========================= */

.theory-hero .hero-badge-logo{

    width:38px;

    height:38px;

    display:flex;

    align-items:center;

    justify-content:center;

    flex-shrink:0;

}



/* =========================
LOGO IMAGE MOBILE
========================= */

.theory-hero .hero-logo{

    width:34px;

    height:34px;

    max-width:34px;

    max-height:34px;

    object-fit:contain;

    display:block;

}



/* =========================
TEXT MOBILE
========================= */

.theory-hero .hero-badge-text{

    gap:2px;

}



.theory-hero .hero-badge-title{

    font-size:14px;

    line-height:1.12;

    letter-spacing:-0.2px;
    
}



.theory-hero .hero-badge-sub{

    font-size:10px;

    line-height:1.12;

}



/* =========================
RIGHT USER CARD
========================= */

.theory-hero .user-card{

    padding:7px 12px;

    border-radius:16px;

}



.theory-hero .user-avatar{

    width:34px;

    height:34px;

    font-size:14px;

}



.theory-hero .user-name{

    font-size:13px;

}



.theory-hero .user-meta{

    font-size:11px;

}



}



/* =====================================================
IPHONE NHỎ
===================================================== */

@media(max-width:390px){


.theory-hero{

    min-height:48px;

    padding:6px 10px;

}



/* badge */

.theory-hero .hero-badge{

    height:42px;

    min-height:42px;

    padding:5px 12px 5px 8px;

    gap:8px;

}



/* logo */

.theory-hero .hero-badge-logo{

    width:34px;

    height:34px;

}



.theory-hero .hero-logo{

    width:30px;

    height:30px;

    max-width:30px;

    max-height:30px;

}



/* text */

.theory-hero .hero-badge-title{

    font-size:13px;

}



.theory-hero .hero-badge-sub{

    font-size:9px;

}


}


/* =========================================================
   MOBILE PDF VIEWER
========================================================= */

.mobile-pdf-toolbar{

    width:100%;

    min-height:46px;

    display:flex;

    align-items:center;

    justify-content:space-between;

    gap:8px;

    padding:6px 8px;

    background:#ffffff;

    border-bottom:1px solid #dbe5f5;

    box-sizing:border-box;

    position:sticky;

    top:0;

    z-index:20;

}


/* Tên bài */

.mobile-pdf-title{

    min-width:0;

    flex:1;

    overflow:hidden;

    white-space:nowrap;

    text-overflow:ellipsis;

    font-size:12px;

    font-weight:700;

    color:#334155;

}


/* Cụm zoom */

.mobile-pdf-controls{

    display:flex;

    align-items:center;

    gap:5px;

    flex-shrink:0;

}


/* =========================================================
   NÚT - / +
========================================================= */

.pdf-zoom-btn{

    width:32px;

    height:32px;

    min-width:32px;

    min-height:32px;

    max-width:32px;

    max-height:32px;

    padding:0;

    margin:0;

    border:none;

    border-radius:8px;

    background:#2563eb;

    color:#fff;

    font-size:21px;

    line-height:32px;

    font-weight:700;

    display:flex;

    align-items:center;

    justify-content:center;

    flex:none;

    box-sizing:border-box;

    cursor:pointer;

    -webkit-tap-highlight-color:transparent;

    appearance:none;

}


/* Khi bị giới hạn zoom */

.pdf-zoom-btn:disabled{

    opacity:.35;

    cursor:not-allowed;

}


/* =========================================================
   HIỂN THỊ %
========================================================= */

.pdf-zoom-value{

    min-width:48px;

    width:48px;

    height:32px;

    min-height:32px;

    max-height:32px;

    padding:0 5px;

    margin:0;

    border-radius:8px;

    background:#eff6ff;

    color:#1d4ed8;

    font-size:11px;

    line-height:32px;

    font-weight:800;

    display:flex;

    align-items:center;

    justify-content:center;

    box-sizing:border-box;

    flex:none;

}


/* =========================================================
   VÙNG CHỨA PDF
========================================================= */

.mobile-pdf-viewer{

    width:100%;

    height:calc(100vh - 180px);

    min-height:500px;

    overflow:auto;

    overflow-x:auto;

    background:#e5e7eb;

    position:relative;

    -webkit-overflow-scrolling:touch;

}


/* =========================================================
   LỚP SCALE
========================================================= */

.mobile-pdf-scale{

    width:100%;

    min-height:100%;

    transform-origin:top center;

    transition:transform .18s ease;

    box-sizing:border-box;

}


/* =========================================================
   PDF IFRAME
========================================================= */

.mobile-pdf-scale .lesson-frame{

    display:block;

    width:100% !important;

    height:calc(100vh - 180px) !important;

    min-height:500px !important;

    max-height:none !important;

    border:none !important;

    border-radius:0 !important;

    background:#fff;

}


/* =========================================================
   MOBILE NHỎ
========================================================= */

@media(max-width:480px){

    .mobile-pdf-toolbar{

        min-height:42px;

        padding:5px 6px;

    }


    .mobile-pdf-title{

        font-size:11px;

    }


    /* Nút vuông cân đối tuyệt đối */

    .pdf-zoom-btn{

        width:30px;

        height:30px;

        min-width:30px;

        min-height:30px;

        max-width:30px;

        max-height:30px;

        padding:0;

        margin:0;

        font-size:19px;

        line-height:30px;

        border-radius:7px;

    }


    /* Ô % cao bằng nút */

    .pdf-zoom-value{

        min-width:44px;

        width:44px;

        height:30px;

        min-height:30px;

        max-height:30px;

        padding:0 4px;

        margin:0;

        font-size:10.5px;

        line-height:30px;

        border-radius:7px;

    }


    .mobile-pdf-viewer{

        height:calc(100vh - 160px);

        min-height:450px;

    }


    .mobile-pdf-scale .lesson-frame{

        height:calc(100vh - 160px) !important;

        min-height:450px !important;

    }

}


/* =========================================================
   FINAL VIEWER FIX
   Mục tiêu:
   - Mở rộng tối đa vùng hiển thị tài liệu trên desktop
   - Không còn bị bó chiều cao bởi min-height 700/780px
   - Giữ nguyên giao diện hiện tại
   - Không ảnh hưởng logic mobile/zoom hiện có
   ========================================================= */

@media (min-width: 769px) {

    /* Khung bên trái chiếm toàn bộ chiều cao khả dụng */
    .viewer {
        display: flex !important;
        flex-direction: column !important;
        height: 100% !important;
        min-height: 0 !important;
        overflow: hidden !important;
    }

    /*
       viewer-box là vùng cần được ưu tiên chiều cao.
       Header và "Tài liệu khác" vẫn giữ nguyên,
       phần còn lại dành cho tài liệu.
    */
    .viewer-box {
        flex: 1 1 0 !important;
        width: 100% !important;
        min-height: 0 !important;
        height: auto !important;
        overflow: auto !important;
        box-sizing: border-box !important;
        padding: 8px !important;
    }

    /* iframe lấp đầy toàn bộ viewer-box */
    .viewer-box .lesson-frame,
    .viewer-box iframe.lesson-frame {
        display: block !important;
        width: 100% !important;
        height: 100% !important;
        min-height: 0 !important;
        max-height: none !important;
        flex: 1 1 auto !important;
        border: none !important;
        box-sizing: border-box !important;
    }

    /* Placeholder cũng không ép khung cao 700/780px */
    .viewer-box .viewer-placeholder {
        width: 100% !important;
        min-height: 100% !important;
        height: 100% !important;
        box-sizing: border-box !important;
    }

    /* Không để khu vực tài liệu khác chiếm quá nhiều chiều cao */
    .material-extra-list-wrapper {
        flex: 0 0 auto !important;
    }
}

/* =========================================================
   DESKTOP LARGE SCREEN
   Tận dụng thêm không gian màn hình lớn
   ========================================================= */
@media (min-width: 1200px) {
    .viewer-box {
        padding: 6px !important;
    }
}

/* =========================================================
   MOBILE: giữ nguyên cơ chế PDF/zoom hiện tại
   ========================================================= */
@media (max-width: 768px) {
    .viewer-box {
        min-height: 0 !important;
        height: auto !important;
    }
}

/* =========================================================
   NÚT XÓA BÀI HỌC - CHỈ ADMIN
   ========================================================= */

.lesson {
    position: relative;
}

.lesson-delete-btn {
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);

    width: 32px;
    height: 32px;

    display: flex;
    align-items: center;
    justify-content: center;

    border: none;
    border-radius: 8px;

    background: transparent;
    cursor: pointer;

    font-size: 17px;
    line-height: 1;

    padding: 0;
    margin: 0;

    z-index: 50;

    pointer-events: auto;
}

.lesson-delete-btn:hover {
    background: #fee2e2;
    transform: translateY(-50%) scale(1.08);
}

.lesson-delete-btn:active {
    transform: translateY(-50%) scale(.94);
}

/* =========================================================
   DELETE LESSON MODAL
   ========================================================= */

.delete-lesson-modal {
    position: fixed;
    inset: 0;

    display: none;

    align-items: center;
    justify-content: center;

    padding: 20px;

    background: rgba(15, 23, 42, .58);

    z-index: 99999;

    backdrop-filter: blur(3px);
}

.delete-lesson-modal.show {
    display: flex;
}

.delete-lesson-dialog {
    width: min(440px, 100%);

    background: #fff;

    border-radius: 18px;

    padding: 24px;

    box-shadow:
        0 20px 60px rgba(0, 0, 0, .25);

    animation: deleteLessonModalIn .18s ease-out;
}

@keyframes deleteLessonModalIn {

    from {
        opacity: 0;
        transform: translateY(10px) scale(.97);
    }

    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }

}

.delete-lesson-icon {
    width: 54px;
    height: 54px;

    margin: 0 auto 12px;

    display: flex;
    align-items: center;
    justify-content: center;

    border-radius: 50%;

    background: #fff7ed;

    font-size: 28px;
}

.delete-lesson-title {
    text-align: center;

    font-size: 20px;
    font-weight: 700;

    color: #1e293b;

    margin-bottom: 18px;
}

.delete-lesson-content {
    text-align: center;

    color: #475569;

    font-size: 14px;

    line-height: 1.55;
}

.delete-lesson-content p {
    margin: 0 0 8px;
}

.delete-lesson-name {
    margin: 12px 0 14px;

    padding: 12px 14px;

    border-radius: 10px;

    background: #f8fafc;

    border: 1px solid #e2e8f0;

    color: #0f172a;

    font-weight: 700;
}

.delete-lesson-warning {
    color: #b45309;

    font-size: 13px;
}

.delete-lesson-actions {
    display: flex;

    justify-content: flex-end;

    gap: 10px;

    margin-top: 22px;
}

.delete-lesson-actions button {
    min-width: 115px;

    height: 40px;

    padding: 0 16px;

    border-radius: 9px;

    font-size: 13px;

    font-weight: 600;

    cursor: pointer;
}

.delete-lesson-cancel {
    border: 1px solid #cbd5e1;

    background: #fff;

    color: #475569;
}

.delete-lesson-cancel:hover {
    background: #f8fafc;
}

.delete-lesson-confirm {
    border: none;

    background: #dc2626;

    color: #fff;
}

.delete-lesson-confirm:hover {
    background: #b91c1c;
}

.delete-lesson-confirm:disabled {
    opacity: .6;
    cursor: not-allowed;
}

@media (max-width: 768px) {

    .lesson-delete-btn {
        right: 5px;

        width: 30px;
        height: 30px;

        font-size: 15px;
    }

    .delete-lesson-dialog {
        padding: 20px;

        border-radius: 16px;
    }

    .delete-lesson-actions button {
        flex: 1;

        min-width: 0;
    }

}