/* ==========================================================================
   GIAO DIỆN PHÂN HỆ: CÁC BÀI TẬP RÈN LUYỆN - MODERN CORPORATE ENTERPRISE SAAS
   Chuẩn mực thiết kế tinh giản, sắc nét, tương thích mọi độ phân giải màn hình
   ========================================================================== */

.exercises-page-wrapper {
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

/* 1. KHỐI TIÊU ĐỀ TRANG VÀ NÚT HÀNH ĐỘNG */
.exercises-header-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 18px;
    flex-wrap: wrap;
    gap: 14px;
}

.exercises-header-title {
    font-size: 21px;
    font-weight: 700;
    color: #0F172A;
    margin: 0 0 3px 0;
    letter-spacing: -0.01em;
}

.exercises-header-subtitle {
    font-size: 13px;
    color: #64748B;
    margin: 0;
    font-weight: 400;
}

/* 2. LƯỚI 3 THẺ THỐNG KÊ TỔNG QUAN (GIẢM CHIỀU CAO, PHÂN CẤP THỊ GIÁC RÕ RÀNG) */
.exercises-stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
    margin-bottom: 18px;
}

.exercise-stat-card {
    background: #FFFFFF;
    border: 1px solid #E2E8F0;
    border-radius: 10px;
    padding: 13px 16px;
    display: flex;
    align-items: center;
    gap: 14px;
    box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.exercise-stat-card:hover {
    transform: translateY(-1px);
    box-shadow: 0 3px 8px rgba(15, 23, 42, 0.06);
    border-color: #CBD5E1;
}

.exercise-stat-icon-wrapper {
    width: 42px;
    height: 42px;
    border-radius: 9px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.stat-icon-blue {
    background: #EFF6FF;
    color: #2563EB;
    border: 1px solid #DBEAFE;
}

.stat-icon-teal {
    background: #F0FDF4;
    color: #0D9488;
    border: 1px solid #CCFBF1;
}

.stat-icon-orange {
    background: #FFF7ED;
    color: #EA580C;
    border: 1px solid #FFEDD5;
}

.exercise-stat-content {
    flex: 1;
    min-width: 0;
}

.exercise-stat-label {
    font-size: 11.5px;
    font-weight: 600;
    color: #64748B;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    margin-bottom: 2px;
}

.exercise-stat-value {
    font-size: 24px;
    font-weight: 700;
    color: #0F172A;
    line-height: 1.15;
}

.exercise-stat-desc {
    font-size: 11px;
    color: #94A3B8;
    margin-top: 2px;
}

/* 3. BỘ LỌC VÀ TÌM KIẾM BÀI TẬP */
.exercise-filter-card {
    padding: 12px 16px;
    margin-bottom: 16px;
    border: 1px solid #E2E8F0;
    border-radius: 10px;
    background: #FFFFFF;
    box-shadow: 0 1px 2px rgba(15, 23, 42, 0.03);
}

.exercise-filter-row {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
}

.exercise-search-box {
    flex: 1;
    min-width: 260px;
}

.exercise-search-box .form-control {
    height: 38px;
    font-size: 13px;
    border-radius: 8px;
    border: 1px solid #CBD5E1;
    transition: all 0.15s ease;
}

.exercise-search-box .form-control:focus {
    border-color: #2563EB;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.exercise-category-select-box {
    width: 240px;
}

.exercise-category-select-box .form-control {
    height: 38px;
    font-size: 13px;
    border-radius: 8px;
    border: 1px solid #CBD5E1;
    cursor: pointer;
}

.exercise-filter-actions .btn {
    height: 38px;
    padding: 0 14px;
    font-size: 13px;
    border-radius: 8px;
}

/* 4. ĐỊNH DẠNG BẢNG DỮ LIỆU BÀI TẬP */
.exercise-table-row {
    border-bottom: 1px solid #F1F5F9;
    transition: background-color 0.12s ease;
}

.exercise-table-row:hover {
    background-color: #F8FAFC;
}

.exercise-item-title {
    font-weight: 600;
    color: #0F172A;
    font-size: 14px;
    margin-bottom: 4px;
    line-height: 1.4;
}

.exercise-item-content {
    font-size: 12.5px;
    color: #475569;
    line-height: 1.5;
    white-space: pre-wrap;
    word-break: break-word;
}

/* NHÃN PHÂN LOẠI THÂN THIỆN */
.exercise-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 11.5px;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 6px;
    letter-spacing: 0.01em;
    white-space: nowrap;
}

.exercise-badge-tech {
    background: #EFF6FF;
    color: #1D4ED8;
    border: 1px solid #DBEAFE;
}

.exercise-badge-fit {
    background: #F0FDF4;
    color: #15803D;
    border: 1px solid #DCFCE7;
}

/* LIÊN KẾT YOUTUBE / TÀI LIỆU KHÔNG VỠ BẢNG */
.exercise-link-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: #F1F5F9;
    color: #334155;
    padding: 5px 10px;
    border-radius: 6px;
    font-weight: 500;
    font-size: 12.5px;
    text-decoration: none;
    border: 1px solid #E2E8F0;
    transition: all 0.15s ease;
    max-width: 230px;
    overflow: hidden;
}

.exercise-link-text {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.exercise-link-badge:hover {
    background: #E2E8F0;
    color: #0F172A;
    text-decoration: none;
}

.exercise-link-badge.is-youtube {
    background: #FEF2F2;
    color: #DC2626;
    border-color: #FEE2E2;
}

.exercise-link-badge.is-youtube:hover {
    background: #FEE2E2;
    color: #B91C1C;
    border-color: #FECACA;
}

.yt-play-icon, .doc-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

/* NÚT THAO TÁC SỬA / XÓA */
.btn-action-icon {
    width: 32px;
    height: 32px;
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    border: 1px solid #E2E8F0;
    background: #FFFFFF;
    color: #475569;
    transition: all 0.15s ease;
}

.btn-action-icon:hover {
    background: #F1F5F9;
    color: #0F172A;
    border-color: #CBD5E1;
}

.btn-action-delete {
    color: #DC2626;
}

.btn-action-delete:hover {
    background: #FEF2F2;
    color: #B91C1C;
    border-color: #FCA5A5;
}

/* ==========================================================================
   4. NÚT THÊM BÀI TẬP VÀ HIỂN THỊ CARD MOBILE THEO MẪU THIẾT KẾ
   ========================================================================== */

.btn-add-exercise {
    background: #EA580C !important;
    color: #FFFFFF !important;
    font-weight: 700 !important;
    font-size: 14px !important;
    padding: 8px 18px !important;
    border-radius: 8px !important;
    border: none !important;
    display: inline-flex !important;
    align-items: center !important;
    gap: 6px !important;
    box-shadow: 0 2px 6px rgba(234, 88, 12, 0.25) !important;
    cursor: pointer !important;
    transition: all 0.2s ease !important;
}

.btn-add-exercise:hover {
    background: #C2410C !important;
    transform: translateY(-1px) !important;
    box-shadow: 0 4px 10px rgba(234, 88, 12, 0.35) !important;
}

.btn-add-plus {
    font-size: 16px;
    font-weight: 800;
    line-height: 1;
}

/* Mặc định trên Desktop: Hiện bảng, ẩn Card mobile */
.desktop-only-exercises {
    display: block;
}

.mobile-only-exercises {
    display: none;
}

/* ==========================================================================
   5. RESPONSIVE BREAKPOINTS (1440px, 1280px, 1024px, 768px, 375px)
   ========================================================================== */

/* Laptop / Màn hình nhỏ (<= 1024px) */
@media (max-width: 1024px) {
    .exercises-stats-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }

    .exercise-stat-card {
        padding: 10px 12px;
        gap: 10px;
    }

    .exercise-stat-value {
        font-size: 21px;
    }

    .exercise-stat-icon-wrapper {
        width: 36px;
        height: 36px;
    }
}

/* ==========================================================================
   GIAO DIỆN MOBILE ĐIỆN THOẠI (<= 768px): CHUẨN XÁC 100% THEO HÌNH MẪU FITCLUB
   ========================================================================== */
@media (max-width: 768px) {
    /* 1. Tiêu đề và nút Thêm màu cam nằm ngang hàng */
    .exercises-header-section {
        display: flex !important;
        flex-direction: row !important;
        justify-content: space-between !important;
        align-items: flex-start !important;
        margin-bottom: 16px !important;
        gap: 10px !important;
    }

    .exercises-header-text {
        flex: 1;
        min-width: 0;
    }

    .exercises-header-title {
        font-size: 23px !important;
        font-weight: 800 !important;
        color: #0F172A !important;
        letter-spacing: -0.02em !important;
        margin: 0 0 4px 0 !important;
    }

    .exercises-header-subtitle {
        font-size: 13.5px !important;
        color: #64748B !important;
        margin: 0 !important;
        line-height: 1.4 !important;
    }

    .btn-add-exercise {
        padding: 8px 16px !important;
        font-size: 14px !important;
        flex-shrink: 0 !important;
    }

    /* 2. Ẩn 3 thẻ thống kê trên mobile theo đúng hình mẫu */
    .exercises-stats-grid {
        display: none !important;
    }

    /* 3. Thanh tìm kiếm và bộ lọc tối ưu cho chiều rộng điện thoại */
    .exercise-filter-card {
        background: transparent !important;
        border: none !important;
        box-shadow: none !important;
        padding: 0 !important;
        margin-bottom: 16px !important;
    }

    .exercise-filter-row {
        display: flex !important;
        flex-direction: row !important;
        align-items: center !important;
        gap: 10px !important;
    }

    .exercise-search-box {
        flex: 1 !important;
        min-width: 0 !important;
    }

    .exercise-search-box .form-control {
        height: 44px !important;
        border-radius: 12px !important;
        border: 1px solid #E2E8F0 !important;
        background: #FFFFFF !important;
        font-size: 13.5px !important;
        padding: 0 12px 0 38px !important;
        box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02) !important;
    }

    .search-lens-icon {
        position: absolute;
        left: 12px;
        top: 50%;
        transform: translateY(-50%);
        display: inline-flex;
        align-items: center;
        pointer-events: none;
    }

    .exercise-category-select-box {
        width: auto !important;
        flex-shrink: 0 !important;
    }

    .filter-select-wrap {
        position: relative;
        width: 116px;
    }

    .filter-select-wrap select {
        height: 44px !important;
        border-radius: 12px !important;
        border: 1px solid #E2E8F0 !important;
        background: #FFFFFF !important;
        font-size: 13.5px !important;
        font-weight: 700 !important;
        color: #0F172A !important;
        padding: 0 28px 0 32px !important;
        appearance: none !important;
        -webkit-appearance: none !important;
        box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02) !important;
        cursor: pointer;
    }

    .filter-funnel-icon {
        position: absolute;
        left: 11px;
        top: 50%;
        transform: translateY(-50%);
        pointer-events: none;
        display: inline-flex;
        align-items: center;
    }

    .filter-arrow-down {
        position: absolute;
        right: 10px;
        top: 50%;
        transform: translateY(-50%);
        pointer-events: none;
        display: inline-flex;
        align-items: center;
    }

    .exercise-filter-actions {
        display: none !important; /* Ẩn nút đặt lại trên mobile để thanh search và filter trọn vẹn 1 hàng như ảnh mẫu */
    }

    /* 4. Chuyển đổi hiển thị: Ẩn bảng desktop, kích hoạt danh sách Card Mobile */
    .desktop-only-exercises {
        display: none !important;
    }

    .mobile-only-exercises {
        display: flex !important;
        flex-direction: column !important;
        gap: 12px !important;
    }

    /* THẺ BÀI TẬP MODERN CORPORATE SAAS (MOBILE CARD) */
    .mobile-exercise-card-item {
        background: #FFFFFF !important;
        border: 1px solid #F1F5F9 !important;
        border-radius: 16px !important;
        padding: 16px !important;
        box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04) !important;
        display: flex !important;
        align-items: flex-start !important;
        gap: 14px !important;
        transition: transform 0.15s ease, box-shadow 0.15s ease !important;
    }

    .mobile-exercise-card-item:active {
        background: #F8FAFC !important;
        transform: scale(0.995) !important;
    }

    /* Khối icon vuông bo góc bên trái */
    .mobile-card-icon-box {
        width: 52px !important;
        height: 52px !important;
        border-radius: 14px !important;
        display: flex !important;
        align-items: center !important;
        justify-content: center !important;
        flex-shrink: 0 !important;
    }

    .icon-bg-green {
        background: #F0FDF4 !important;
    }

    .icon-bg-blue {
        background: #EFF6FF !important;
    }

    .icon-bg-orange {
        background: #FFF7ED !important;
    }

    /* Khối chi tiết bên phải */
    .mobile-card-details {
        flex: 1 !important;
        min-width: 0 !important;
    }

    .mobile-card-header-row {
        display: flex !important;
        justify-content: space-between !important;
        align-items: flex-start !important;
        gap: 8px !important;
        margin-bottom: 4px !important;
    }

    .mobile-card-title {
        font-size: 15.5px !important;
        font-weight: 700 !important;
        color: #0F172A !important;
        line-height: 1.35 !important;
        margin: 0 !important;
        letter-spacing: -0.01em !important;
    }

    .mobile-card-dots-btn {
        background: transparent !important;
        border: none !important;
        color: #64748B !important;
        padding: 2px 4px !important;
        cursor: pointer !important;
        border-radius: 6px !important;
        display: inline-flex !important;
        align-items: center !important;
        justify-content: center !important;
        min-width: 28px !important;
        min-height: 28px !important;
        touch-action: manipulation !important;
    }

    .mobile-card-dots-btn:active {
        background: #E2E8F0 !important;
        color: #0F172A !important;
    }

    .mobile-card-desc {
        font-size: 13px !important;
        color: #64748B !important;
        line-height: 1.45 !important;
        margin: 0 0 8px 0 !important;
        word-break: break-word !important;
    }

    .mobile-card-tag-row {
        margin-bottom: 12px !important;
    }

    .mobile-tag-pill {
        display: inline-flex !important;
        align-items: center !important;
        gap: 5px !important;
        padding: 4px 10px !important;
        border-radius: 20px !important;
        font-size: 11px !important;
        font-weight: 800 !important;
        text-transform: uppercase !important;
        letter-spacing: 0.02em !important;
    }

    .tag-pill-green {
        background: #DCFCE7 !important;
        color: #15803D !important;
    }

    .tag-pill-blue {
        background: #DBEAFE !important;
        color: #1D4ED8 !important;
    }

    /* Footer thẻ: xem video | người phụ trách */
    .mobile-card-footer-row {
        display: flex !important;
        align-items: center !important;
        gap: 10px !important;
        font-size: 12.5px !important;
        color: #64748B !important;
        flex-wrap: wrap !important;
    }

    .mobile-card-video-link {
        display: inline-flex !important;
        align-items: center !important;
        gap: 6px !important;
        color: #0F2D4A !important;
        font-weight: 600 !important;
        text-decoration: none !important;
    }

    .video-circle-icon {
        width: 20px !important;
        height: 20px !important;
        border-radius: 50% !important;
        background: #EFF6FF !important;
        color: #2563EB !important;
        display: inline-flex !important;
        align-items: center !important;
        justify-content: center !important;
        flex-shrink: 0 !important;
    }

    .mobile-card-no-video {
        color: #94A3B8 !important;
        font-size: 12px !important;
    }

    .mobile-card-divider {
        color: #E2E8F0 !important;
        font-size: 12px !important;
    }

    .mobile-card-author-wrap {
        display: inline-flex !important;
        align-items: center !important;
        gap: 6px !important;
    }

    .author-circle-avatar {
        width: 20px !important;
        height: 20px !important;
        border-radius: 50% !important;
        background: #EDE9FE !important;
        color: #7C3AED !important;
        font-size: 10.5px !important;
        font-weight: 800 !important;
        display: inline-flex !important;
        align-items: center !important;
        justify-content: center !important;
        flex-shrink: 0 !important;
    }

    .author-name-text {
        font-size: 12.5px !important;
        color: #64748B !important;
        font-weight: 500 !important;
    }

    .mobile-exercise-empty {
        text-align: center;
        padding: 40px 20px;
        background: #FFFFFF;
        border-radius: 16px;
        border: 1px dashed #CBD5E1;
    }
}

/* Điện thoại nhỏ (<= 375px) */
@media (max-width: 375px) {
    .exercises-header-title {
        font-size: 20px !important;
    }

    .filter-select-wrap {
        width: 102px !important;
    }

    .mobile-exercise-card-item {
        padding: 12px !important;
        gap: 10px !important;
    }

    .mobile-card-icon-box {
        width: 44px !important;
        height: 44px !important;
    }
}