:root {
    --green: #3a7d24; --yellow: #fba100; --grey: #8a8a8a; 
    --bg-light: #f9fafb; --text-dark: #1f2937; --white: #ffffff; --gold: #d4af37;
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Nunito', sans-serif; }
body { background-color: var(--bg-light); color: var(--text-dark); overflow-x: hidden; }

/* NÚT BẤM CHUNG */
.btn-primary { background-color: var(--yellow); color: var(--white); border: none; padding: 10px 24px; font-weight: 800; border-radius: 50px; cursor: pointer; transition: 0.3s; box-shadow: 0 4px 15px rgba(251, 161, 0, 0.3); }
.btn-primary:hover { background-color: #e08f00; transform: translateY(-2px); }
.btn-outline { background: transparent; color: var(--green); border: 2px solid var(--green); padding: 10px 24px; font-weight: 800; border-radius: 50px; cursor: pointer; transition: 0.3s; }
.btn-outline:hover { background: var(--green); color: white; }
.btn-disabled { background: #d1d5db !important; color: white !important; cursor: not-allowed; box-shadow: none; border: none; }

/* NÚT XÓA ICON */
.btn-icon-danger { background: #fee2e2; color: #ef4444; border: none; width: 35px; height: 35px; border-radius: 50%; cursor: pointer; transition: 0.2s; display: flex; justify-content: center; align-items: center;}
.btn-icon-danger:hover { background: #ef4444; color: white; transform: scale(1.1); }

/* HEADER & DYNAMIC MENU */
header { background: var(--white); padding: 15px 50px; display: flex; justify-content: space-between; align-items: center; box-shadow: 0 2px 10px rgba(0,0,0,0.05); position: sticky; top: 0; z-index: 100; transition: background 0.3s;}

/* Update Logo Styles */
.logo { font-size: 2.2rem; font-weight: 900; letter-spacing: -1px; display: flex; flex-direction: column; line-height: 1; cursor: pointer; text-decoration: none;}
.logo-text span:nth-child(1) { color: var(--green); transition: color 0.3s; }
.logo-text span:nth-child(2) { color: var(--yellow); }
.logo-text span:nth-child(3) { color: var(--green); transition: color 0.3s; }
.slogan { font-size: 0.85rem; color: var(--grey); font-style: italic; font-weight: 600; margin-top: 5px; text-align: left; transition: color 0.3s;}

.nav-menu { display: flex; gap: 30px; align-items: center; }
.nav-link { 
    text-decoration: none; 
    color: var(--text-dark); 
    font-weight: 800; 
    font-size: 1.05rem; 
    transition: 0.3s; 
    padding-bottom: 5px; 
    display: inline-flex; /* Giúp căn chỉnh icon và chữ nằm ngang đẹp hơn */
    align-items: center;
    gap: 6px;
    white-space: nowrap; /* BẮT BUỘC: Ngăn chữ bị rớt xuống dòng */
}
/*
.nav-link { 
    text-decoration: none; color: var(--text-dark); font-weight: 800; font-size: 1.05rem; transition: 0.3s; padding-bottom: 5px; 
}
*/
.nav-link:hover, .nav-link.active { 
    color: var(--green); border-bottom: 2px solid var(--green); 
}
.nav-locked { opacity: 0.7; }
.nav-locked:hover { opacity: 1; color: var(--yellow); border-bottom: 2px solid var(--yellow); }
.header-actions { display: flex; gap: 15px; align-items: center; }

/* BỐ CỤC CHUNG */
.container { max-width: 1200px; margin: 40px auto; padding: 0 20px; }
.card { background: var(--white); padding: 30px; border-radius: 20px; box-shadow: 0 10px 30px rgba(0,0,0,0.05); margin-bottom: 20px; }
.dashboard-grid { display: grid; grid-template-columns: 2.5fr 1fr; gap: 20px; }

/* MODAL CHUNG (LOGIN & VIDEO & QUẢN LÝ) */
.modal { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.85); z-index: 10000; justify-content: center; align-items: center; }
.modal-content { background: var(--white); width: 90%; max-width: 800px; border-radius: 20px; overflow: hidden; position: relative; }
.close-modal { position: absolute; top: 15px; right: 20px; font-size: 1.5rem; color: var(--grey); cursor: pointer; z-index: 10; transition: 0.3s; }
.close-modal:hover { color: #ef4444; }

/* GIAO DIỆN AUTH (LOGIN/OTP) */
.form-input { width: 100%; padding: 12px 15px; border: 2px solid #e5e7eb; border-radius: 10px; font-size: 1rem; outline: none; transition: 0.3s; }
.form-input:focus { border-color: var(--green); }
.btn-google { display: flex; align-items: center; justify-content: center; gap: 10px; width: 100%; padding: 12px; background: white; border: 2px solid #e5e7eb; border-radius: 10px; font-weight: bold; cursor: pointer; transition: 0.3s; font-size: 1rem; color: #444;}
.btn-google:hover { background: #f9fafb; border-color: #d1d5db; }

/* QUẢN LÝ TÀI KHOẢN ITEM */
.child-item { display: flex; justify-content: space-between; align-items: center; padding: 12px 15px; background: #f8fafc; border: 1px solid #e5e7eb; border-radius: 10px; margin-bottom: 10px; transition: 0.2s;}
.child-item:hover { border-color: var(--green); }
.account-info-box { background: #f8fafc; padding: 15px; border-radius: 10px; border-left: 4px solid var(--green); margin-bottom: 20px;}
.account-info-box p { margin-bottom: 5px; font-size: 1rem; }

/* GIAO DIỆN INDEX (Landing) */
.hero { text-align: center; padding: 60px 20px; background: linear-gradient(135deg, #e8f5e9 0%, #fff 100%); }
.hero h1 { font-size: 2.8rem; color: var(--green); margin-bottom: 15px; font-weight: 900; }
.hero p { font-size: 1.2rem; color: var(--grey); margin-bottom: 30px; max-width: 600px; margin-left: auto; margin-right: auto; }

.course-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }
.course-card { background: var(--white); padding: 30px 20px; border-radius: 20px; text-align: center; box-shadow: 0 10px 30px rgba(0,0,0,0.05); cursor: pointer; border: 2px solid #eee; transition: 0.3s;}
.course-card:hover { border-color: var(--green); transform: translateY(-5px); }

.video-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 25px; }
.video-card { background: var(--white); border-radius: 15px; overflow: hidden; box-shadow: 0 5px 20px rgba(0,0,0,0.05); cursor: pointer; transition: 0.3s; text-align: center; padding-bottom: 15px; }
.video-card:hover { transform: scale(1.02); }
.thumbnail { height: 180px; background: #e2e8f0; position: relative; display: flex; justify-content: center; align-items: center; }
.thumbnail img { width: 100%; height: 100%; object-fit: cover; opacity: 0.8; }
.play-btn { position: absolute; width: 60px; height: 60px; background: rgba(251, 161, 0, 0.9); border-radius: 50%; display: flex; justify-content: center; align-items: center; color: white; font-size: 1.5rem; transition: 0.3s; }
.video-card:hover .play-btn { background: var(--green); transform: scale(1.1); }
.video-info { padding: 20px; text-align: left;}
.video-tag { background: #e8f5e9; color: var(--green); padding: 4px 10px; border-radius: 20px; font-size: 0.75rem; font-weight: 800; display: inline-block;}

.process-steps { display: flex; justify-content: space-between; flex-wrap: wrap; margin-top: 40px; position: relative; text-align: center;}
.step { width: 15%; min-width: 120px; margin-bottom: 30px; position: relative; z-index: 2; }
.step-icon { width: 70px; height: 70px; background: var(--bg-light); border: 3px solid var(--green); border-radius: 50%; display: flex; justify-content: center; align-items: center; margin: 0 auto 15px; font-size: 1.8rem; color: var(--green); transition: 0.3s;}
.step:hover .step-icon { background: var(--green); color: white; }
.process-line { position: absolute; top: 35px; left: 10%; right: 10%; height: 2px; border-top: 2px dashed #cbd5e1; z-index: 1; }
.step-highlight .step-icon { border-color: var(--yellow); background: var(--yellow); color: white; box-shadow: 0 0 20px rgba(251, 161, 0, 0.4); }
.step-highlight h4 { color: var(--yellow); font-weight: 900; }

/* GIAO DIỆN DASHBOARD (Các trạng thái) */
.app-state { display: none; animation: fadeIn 0.4s ease; }
.app-state.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
.dev-panel { position: fixed; bottom: 20px; left: 20px; background: rgba(0,0,0,0.8); padding: 15px; border-radius: 10px; z-index: 9999; display: flex; flex-direction: column; gap: 10px; border: 2px solid #333;}
.dev-panel p { color: #fff; font-size: 12px; font-weight: bold; margin-bottom: 5px; text-align: center;}
.dev-btn { background: #333; color: lime; border: 1px solid lime; padding: 5px 10px; font-size: 12px; cursor: pointer; border-radius: 5px; font-family: monospace; }
.dev-btn:hover, .dev-btn.active { background: lime; color: #000; }
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 30px; }
.price-card { border: 2px solid #e5e7eb; border-radius: 20px; padding: 30px; text-align: center; position: relative; background: white; }
.price-card.recommend { border-color: var(--yellow); transform: scale(1.05); box-shadow: 0 10px 30px rgba(251, 161, 0, 0.15); z-index: 2; }
.badge { position: absolute; top: -15px; left: 50%; transform: translateX(-50%); background: var(--yellow); color: white; padding: 5px 15px; border-radius: 20px; font-weight: bold; font-size: 0.9rem; }
.user-progress { background: #e5e7eb; height: 12px; border-radius: 10px; overflow: hidden; margin-top: 10px; }
.user-progress-fill { background: var(--green); height: 100%; width: 30%; border-radius: 10px; }
.vip-theme { background: linear-gradient(135deg, #1f2937 0%, #000000 100%); color: white; }
.vip-card { border: 2px solid var(--gold); background: rgba(255, 215, 0, 0.05); }
.vip-text { color: var(--gold); }
.ref-box { display: flex; align-items: center; background: #374151; padding: 10px; border-radius: 10px; margin-top: 15px; }
.ref-box input { flex: 1; background: transparent; border: none; color: white; outline: none; font-family: monospace; font-size: 1.1rem; }

/* GIAO DIỆN BÀI TẬP (HOMEWORK) */
.hw-item { display: flex; justify-content: space-between; align-items: center; padding: 20px; border: 1px solid #eee; border-radius: 15px; margin-bottom: 15px; transition: 0.3s; background: white;}
.hw-item:hover { border-color: var(--green); box-shadow: 0 5px 15px rgba(0,0,0,0.05); }
.hw-deadline { color: #ef4444; font-size: 0.9rem; font-weight: bold; background: #fee2e2; padding: 5px 10px; border-radius: 10px; }

/* GIAO DIỆN HỌC HÁT (SING) */
.song-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 25px; }
.song-card { background: var(--text-dark); border-radius: 15px; overflow: hidden; cursor: pointer; position: relative; color: white; text-align: center; padding-bottom: 15px;}
.song-card img { width: 100%; aspect-ratio: 1/1; object-fit: cover; opacity: 0.8; transition: 0.3s; }
.song-card:hover img { opacity: 1; transform: scale(1.05); }
.play-btn-overlay { position: absolute; top: 40%; left: 50%; transform: translate(-50%, -50%); font-size: 3rem; color: var(--yellow); opacity: 0; transition: 0.3s; }
.song-card:hover .play-btn-overlay { opacity: 1; }

/* GIAO DIỆN LỒNG TIẾNG (DUBBING) */
.dub-layout { display: grid; grid-template-columns: 2fr 1fr; gap: 20px; }
.script-box { background: #f9fafb; padding: 20px; border-radius: 15px; height: 350px; overflow-y: auto; font-size: 1.1rem; line-height: 2; border: 2px solid #e5e7eb;}
.script-line { padding: 5px 10px; border-radius: 8px; transition: 0.3s; cursor: pointer;}
.script-line:hover { background: #eee; }
.script-line.active { background: var(--yellow); color: white; font-weight: bold; }
.record-btn { width: 80px; height: 80px; background: #ef4444; border-radius: 50%; display: flex; justify-content: center; align-items: center; color: white; font-size: 2rem; margin: 20px auto; cursor: pointer; box-shadow: 0 0 20px rgba(239, 68, 68, 0.4); transition: 0.3s; }
.record-btn.recording { animation: pulse 1.5s infinite; background: #10b981; box-shadow: 0 0 20px rgba(16, 185, 129, 0.4); }

/* GIAO DIỆN AI SPEAKING */
.ai-layout { display: grid; grid-template-columns: 1fr 3fr; gap: 20px; height: 600px; }
.ai-sidebar { background: var(--white); border-radius: 20px; padding: 20px; box-shadow: 0 5px 20px rgba(0,0,0,0.05); text-align: center; }
.ai-timer-box { background: #fee2e2; color: #ef4444; padding: 15px; border-radius: 15px; margin: 20px 0; font-size: 1.5rem; font-weight: 900; }
.ai-timer-box.safe { background: #dcfce7; color: var(--green); }
.ai-chat-area { background: var(--white); border-radius: 20px; box-shadow: 0 5px 20px rgba(0,0,0,0.05); display: flex; flex-direction: column; overflow: hidden;}
.chat-history { flex: 1; padding: 20px; overflow-y: auto; background: #f9fafb; display: flex; flex-direction: column; gap: 15px;}
.msg { max-width: 70%; padding: 12px 18px; border-radius: 20px; line-height: 1.5; }
.msg-ai { background: white; border: 1px solid #e5e7eb; align-self: flex-start; border-bottom-left-radius: 5px; }
.msg-user { background: var(--green); color: white; align-self: flex-end; border-bottom-right-radius: 5px; }
.voice-visualizer { height: 100px; background: white; border-top: 1px solid #eee; display: flex; justify-content: center; align-items: center; gap: 5px; padding: 10px; }
.bar { width: 6px; height: 20px; background: var(--yellow); border-radius: 10px; transition: 0.1s; animation: sound 0s infinite ease-in-out alternate; }
@keyframes sound { 0% { height: 10px; } 100% { height: 50px; } }
.ai-record-btn { width: 60px; height: 60px; background: var(--green); color: white; border-radius: 50%; font-size: 1.5rem; display: flex; justify-content: center; align-items: center; cursor: pointer; margin-left: 20px; box-shadow: 0 5px 15px rgba(58, 125, 36, 0.4); }

@media (max-width: 1100px) {
    header { padding: 15px 20px; }
    .nav-menu { gap: 15px; }
}
/* RESPONSIVE */
/* RESPONSIVE */
@media (max-width: 768px) { 
    .dashboard-grid, .dub-layout, .pricing-grid, .ai-layout { grid-template-columns: 1fr; } 
    .process-line { display: none; } 
    .step { width: 45%; } 
    
    /* ===== CSS MỚI CHO HEADER & MENU MOBILE ===== */
    header {
        flex-wrap: wrap; /* Cho phép các thành phần rớt xuống hàng */
        padding: 10px 15px;
        gap: 15px;
    }

    .logo {
        font-size: 1.6rem;
    }

    /* Thu nhỏ nút bấm góc phải */
    .header-actions {
        flex: 1;
        justify-content: flex-end;
        gap: 10px;
    }
    .btn-primary, .btn-outline {
        padding: 8px 12px;
        font-size: 0.85rem;
    }
    #btn-login-header {
        font-size: 0.85rem;
        margin-right: 5px !important;
    }

    /* Thiết kế Menu Mobile dạng lướt ngang (Pill Menu) */
    .nav-menu {
        display: flex; /* Hiển thị lại menu thay vì ẩn đi */
        width: 100%;
        order: 3; /* Đẩy menu xuống hàng thứ 2 dưới logo */
        overflow-x: auto; /* Cho phép vuốt ngang */
        padding-bottom: 5px;
        gap: 10px;
        -webkit-overflow-scrolling: touch; /* Vuốt mượt trên iOS */
        scrollbar-width: none; /* Ẩn thanh cuộn trên Firefox */
    }
    
    /* Ẩn thanh cuộn trên Chrome/Safari/Edge */
    .nav-menu::-webkit-scrollbar {
        display: none;
    }

    /* Tạo hình dáng dạng Chip/Pill cho các nút Menu trên Mobile */
    .nav-link {
        background: #f8fafc;
        padding: 8px 16px;
        border-radius: 20px;
        border: 1px solid #e5e7eb;
        font-size: 0.9rem;
        border-bottom: none !important; /* Xóa gạch chân cũ */
    }

    /* Trạng thái Hover / Active trên Mobile */
    .nav-link:hover, .nav-link.active {
        background: #e8f5e9; /* Nền xanh nhạt */
        border-color: var(--green);
        color: var(--green);
        border-bottom: none !important;
    }

    /* Trạng thái bị khóa trên Mobile */
    .nav-locked:hover {
        background: #fffbe6;
        border-color: var(--yellow);
    }
}

/* ==================================================
   GIAO DIỆN LƯỚI LỊCH (WEEKLY GRID)
   ================================================== */
.calendar-grid-container {
    display: flex;
    overflow-x: auto;
    gap: 15px;
    padding-bottom: 15px;
    scrollbar-width: thin;
    margin-top: 15px;
}
.calendar-grid-container::-webkit-scrollbar { height: 8px; }
.calendar-grid-container::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 10px; }

.calendar-column {
    flex: 0 0 120px;
    background: #f8fafc;
    border: 1px solid #e5e7eb;
    border-radius: 15px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.cal-col-header {
    background: #e2e8f0;
    padding: 10px;
    text-align: center;
    border-bottom: 1px solid #e5e7eb;
}
.cal-col-header .day-name { font-size: 0.85rem; color: var(--grey); font-weight: bold; }
.cal-col-header .day-date { font-size: 1.1rem; color: var(--text-dark); font-weight: 900; }

.cal-col-body { padding: 10px; display: flex; flex-direction: column; gap: 8px; }

.cal-time-slot {
    background: white;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    padding: 8px 0;
    text-align: center;
    font-weight: bold;
    color: var(--text-dark);
    font-size: 0.95rem;
    cursor: pointer;
    transition: 0.2s;
}
.cal-time-slot:hover:not(.disabled) { border-color: var(--green); color: var(--green); transform: translateY(-2px); }
.cal-time-slot.active { background: var(--green); color: white; border-color: var(--green); box-shadow: 0 4px 10px rgba(58,125,36,0.3); }
.cal-time-slot.disabled { background: #f3f4f6; color: #9ca3af; text-decoration: line-through; cursor: not-allowed; border-color: #f3f4f6; }

/* Ẩn hiện nội dung Optional */
details.optional-fields summary {
    font-weight: bold; color: var(--grey); cursor: pointer; outline: none; padding: 10px 0; border-top: 1px dashed #e5e7eb; margin-top: 15px;
}
details.optional-fields summary:hover { color: var(--green); }
/* ==================================================
   GIAO DIỆN CHIP (LỰA CHỌN MỤC TIÊU / PHƯƠNG PHÁP)
   ================================================== */
.booking-section { margin-bottom: 25px; text-align: left; }
.booking-section h4 { font-size: 1rem; color: var(--text-dark); margin-bottom: 10px; font-weight: 800; }
.chip-group { display: flex; flex-wrap: wrap; gap: 10px; }
.chip { padding: 8px 15px; border: 2px solid #e5e7eb; border-radius: 20px; font-size: 0.9rem; cursor: pointer; transition: 0.2s; background: white; color: var(--grey); font-weight: bold;}
.chip:hover { border-color: var(--green); color: var(--green); }
.chip.active { background: #e8f5e9; border-color: var(--green); color: var(--green); box-shadow: 0 4px 10px rgba(58,125,36,0.1); }

.form-textarea { width: 100%; padding: 15px; border: 2px solid #e5e7eb; border-radius: 12px; font-size: 0.95rem; outline: none; transition: 0.3s; resize: vertical; min-height: 80px; font-family: inherit; }
.form-textarea:focus { border-color: var(--green); }

/* Thêm thanh cuộn cho Modal Booking & Modal Payment để tránh bị quá dài màn hình */
#booking-content,
#package-payment-content { 
    max-height: 65vh; 
    overflow-y: auto; 
    padding-right: 5px; 
    padding-bottom: 50px; /* Thêm đệm đáy để cuộn form thẻ của PayPal không bị kẹt */
    scrollbar-width: thin; 
}
#booking-content::-webkit-scrollbar,
#package-payment-content::-webkit-scrollbar { width: 6px; }
#booking-content::-webkit-scrollbar-thumb,
#package-payment-content::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 10px; }

/* FIX UX: Đảm bảo vùng chứa PayPal có đủ không gian để nở form Credit Card */
#paypal-button-container, 
#paypal-package-button-container {
    min-height: 200px;
    padding-bottom: 100px;
    transition: all 0.3s ease;
}

/* FIX UX: Đảm bảo vùng chứa PayPal có đủ không gian để nở form Credit Card */
#paypal-button-container, 
#paypal-package-button-container {
    min-height: 200px;
    padding-bottom: 100px;
    transition: all 0.3s ease;
}

/* ==================================================
   GIAO DIỆN BẢNG GIÁ GÓI HỌC (LANDING PAGE)
   ================================================== */
.pkg-card { transition: 0.4s; overflow: hidden;}
.pkg-card:hover { transform: translateY(-10px); box-shadow: 0 15px 40px rgba(0,0,0,0.1); }
.pkg-sessions { background: #e8f5e9; color: var(--green); display: inline-block; padding: 5px 15px; border-radius: 20px; font-weight: 900; font-size: 1.2rem; margin: 15px 0; }
.pkg-validity { color: var(--grey); font-size: 0.9rem; font-weight: bold; margin-bottom: 15px;}
.pkg-price-group { background: #f9fafb; padding: 20px; border-radius: 15px; margin-bottom: 20px; border: 1px dashed #d1d5db;}
.pkg-original-price { color: #9ca3af; text-decoration: line-through; font-size: 1.1rem; font-weight: bold; margin-bottom: 5px;}
.pkg-promo-price { color: #ef4444; font-size: 2.2rem; font-weight: 900; }
.pkg-features { list-style: none; text-align: left; margin-bottom: 20px; }
.pkg-features li { margin-bottom: 12px; color: var(--text-dark); font-size: 0.95rem; display: flex; align-items: flex-start; gap: 10px;}
.pkg-features li i { color: var(--green); margin-top: 4px; }
/* ==================================================
   GIAO DIỆN DASHBOARD MỚI (ĐA HỒ SƠ)
   ================================================== */

/* BỘ CHUYỂN ĐỔI HỒ SƠ */
.profile-switcher {
    display: flex;
    gap: 15px;
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 2px solid #e5e7eb;
}
.profile-card {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--white);
    padding: 12px 20px;
    border-radius: 50px;
    border: 2px solid #e5e7eb;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0,0,0,0.03);
}
.profile-card:hover {
    border-color: var(--green);
    transform: translateY(-2px);
}
.profile-card.active {
    border-color: var(--green);
    background: var(--green);
    color: white;
    box-shadow: 0 5px 15px rgba(58, 125, 36, 0.3);
}
.profile-card i {
    font-size: 1.5rem;
    color: var(--yellow);
}
.profile-card.active i {
    color: white;
}
.profile-card-placeholder {
    height: 60px;
    width: 180px;
    background: #f3f4f6;
    border-radius: 50px;
    animation: pulse-bg 1.5s infinite;
}
@keyframes pulse-bg { 50% { background: #e5e7eb; } }

/* LAYOUT CHÍNH */
.main-dashboard-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 25px;
    align-items: flex-start;
}
@media (max-width: 992px) {
    .main-dashboard-layout { grid-template-columns: 1fr; }
}

/* VÍ BUỔI HỌC */
.session-wallet-title {
    font-size: 1.2rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 20px;
    color: var(--text-dark);
}
.wallet-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}
.wallet-item {
    background: #f8fafc;
    padding: 15px;
    border-radius: 12px;
    text-align: center;
}
.wallet-item .count {
    font-size: 2rem;
    font-weight: 900;
    line-height: 1;
}
.wallet-item .label {
    font-size: 0.85rem;
    color: var(--grey);
    font-weight: bold;
    margin-top: 5px;
}
.wallet-item .count-remaining { color: var(--green); }
.wallet-item .count-scheduled { color: var(--yellow); }
.wallet-item .count-completed { color: #3b82f6; }
.wallet-item .count-missed { color: #ef4444; }

/* NỘI DUNG CHÍNH (THAY THẾ CHO app-state CŨ) */
.dashboard-content .card {
    animation: fadeIn 0.4s ease;
}
/* ==================================================
   GIAO DIỆN DANH SÁCH LỚP HỌC SẮP TỚI
   ================================================== */
.class-card-item {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1.5fr 1fr;
    gap: 15px;
    align-items: center;
    padding: 15px;
    background: #f8fafc;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    transition: all 0.2s ease-in-out;
}
.class-card-item:hover {
    border-color: var(--green);
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}
.class-card-learner {
    font-size: 1.1rem;
    color: var(--text-dark);
}
.class-card-learner i {
    color: var(--green);
    margin-right: 8px;
}
.class-card-time .time-date {
    font-size: 0.9rem;
    color: var(--grey);
}
.class-card-time .time-hour {
    font-size: 1.2rem;
    font-weight: 900;
    color: var(--green);
}
.class-card-teacher {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: bold;
}
.class-card-teacher img {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}
.class-card-teacher-pending {
    background: #fffbe6;
    color: #ca8a04;
    padding: 5px 10px;
    border-radius: 8px;
    font-weight: bold;
    font-size: 0.9rem;
    text-align: center;
}
.class-card-action {
    text-align: right;
}

/* Responsive cho danh sách lớp học */
@media (max-width: 768px) {
    .class-card-item {
        grid-template-columns: 1fr 1fr; /* 2 cột trên mobile */
        grid-template-areas: 
            "learner time"
            "teacher action";
        row-gap: 20px;
    }
    .class-card-learner { grid-area: learner; }
    .class-card-time { grid-area: time; text-align: right;}
    .class-card-teacher, .class-card-teacher-pending { grid-area: teacher; }
    .class-card-action { grid-area: action; }
}
/* ==================================================
   GIAO DIỆN TABS CHO DASHBOARD
   ================================================== */
.dashboard-tabs {
    display: flex;
    gap: 10px;
    border-bottom: 2px solid #e5e7eb;
    margin-bottom: 20px;
}
.tab-button {
    padding: 10px 20px;
    border: none;
    background: transparent;
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--grey);
    cursor: pointer;
    transition: all 0.3s ease;
    border-bottom: 3px solid transparent;
    transform: translateY(2px); /* Dịch xuống để khớp với border-bottom của container */
}
.tab-button:hover {
    color: var(--text-dark);
}
.tab-button.active {
    color: var(--green);
    border-bottom-color: var(--green);
}
.tab-content {
    display: none;
    animation: fadeIn 0.4s ease;
}
.tab-content.active {
    display: block;
}

/* ==================================================
   GIAO DIỆN THẺ BÁO CÁO (HISTORY CARD) - ĐÃ CẬP NHẬT
   ================================================== */
.history-list-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.history-card {
    background: var(--white);
    border: 1px solid #e5e7eb;
    border-radius: 16px;
    padding: 20px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.02);
    transition: all 0.3s ease;
}
.history-card:hover {
    border-color: var(--green);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.05);
}
.history-card-grid {
    display: grid;
    grid-template-columns: 1fr 2.5fr; /* Thay đổi: Layout 2 cột */
    gap: 25px;
    align-items: flex-start; /* Thay đổi: align-items: flex-start để các cột căn lề trên */
}

.history-card-info .learner-name {
    font-size: 1.2rem;
    font-weight: 900;
    color: var(--text-dark);
    margin-bottom: 5px;
}
.history-card-info .class-time {
    font-size: 0.9rem;
    color: var(--grey);
    margin-bottom: 15px;
}
.history-card-info .teacher-info {
    display: flex;
    align-items: center;
    gap: 10px;
}
.history-card-info .teacher-info img {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid #eee;
}

/* Gộp feedback và AI vào một khu vực chung */
.history-card-details {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.feedback-title {
    font-size: 0.95rem;
    font-weight: 800;
    color: var(--green);
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.teacher-feedback {
    background: #f8fafc;
    padding: 15px;
    border-radius: 12px;
    font-size: 0.95rem;
    line-height: 1.6;
    color: #374151;
    max-height: 120px;
    overflow-y: auto;
}

/* CSS mới cho phần AI Evaluation */
.ai-evaluation-section .ai-title {
    color: #8b5cf6; /* Màu tím cho AI */
}
.ai-evaluation-list {
    background: #f5f3ff; /* Nền tím nhạt */
    border: 1px dashed #ddd6fe;
    padding: 15px;
    border-radius: 12px;
    list-style-type: none;
    font-size: 0.9rem;
    color: #374151;
}
.ai-evaluation-list li {
    padding-bottom: 8px;
    margin-bottom: 8px;
    border-bottom: 1px solid #e0d9fe;
}
.ai-evaluation-list li:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}
.ai-evaluation-list strong {
    color: #5b21b6; /* Màu chữ tím đậm hơn */
}


/* Responsive cho Thẻ Báo cáo */
@media (max-width: 768px) {
    .history-card-grid {
        grid-template-columns: 1fr; /* 1 cột trên mobile */
    }
}
/* Thêm đoạn này vào CUỐI FILE style.css */

/* ==================================================
   GIAO DIỆN THẺ BÁO CÁO BỊ HỦY
   ================================================== */
.history-card.history-card-cancelled {
    background-color: #f8fafc;
    opacity: 0.8;
    border-style: dashed;
}

.history-card.history-card-cancelled .learner-name {
    text-decoration: line-through;
    color: var(--grey);
}

.cancellation-reason {
    background: #fee2e2;
    border-left: 4px solid #ef4444;
    padding: 20px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    gap: 15px;
    height: 100%;
}
.cancellation-reason i {
    font-size: 1.8rem;
    color: #b91c1c;
}
.cancellation-reason p {
    color: #520e0e;
    line-height: 1.5;
}

/* Thay thế TOÀN BỘ khối CSS cũ bằng khối mới này */

/* ==================================================
   GIAO DIỆN LỚP HỌC SẮP TỚI (DASHBOARD)
   ================================================== */

/* --- Dành cho khu vực kêu gọi hành động khi lịch trống --- */
.empty-schedule-prompt {
    text-align: center;
    padding: 40px 20px;
    background-color: #f8fafc;
    border: 1px solid #e5e7eb;
    border-radius: 16px;
}
.empty-schedule-prompt h3 {
    font-size: 1.4rem;
    color: var(--text-dark);
    font-weight: 800;
    margin-bottom: 10px;
}
.empty-schedule-prompt p {
    color: var(--grey);
    max-width: 450px;
    margin: 0 auto 25px auto;
    line-height: 1.6;
}
.empty-schedule-prompt .btn-primary {
    background-color: var(--green); /* Nút màu xanh theo yêu cầu */
    font-size: 1.1rem;
    padding: 12px 28px;
    box-shadow: 0 4px 15px rgba(58, 125, 36, 0.2);
    transition: background-color 0.3s ease, transform 0.3s ease;
}
.empty-schedule-prompt .btn-primary:hover {
    background-color: #316a1e; /* Màu xanh đậm hơn khi hover */
    transform: translateY(-2px);
}

/* --- Dành cho header và nút nhỏ khi đã có lịch --- */
.upcoming-classes-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid #e5e7eb;
}
.upcoming-classes-title {
    font-size: 1.3rem;
    color: var(--text-dark);
}
.btn-book-more {
    font-size: 0.95rem;
    padding: 8px 20px;
}

/* --- Container chung cho danh sách lớp học --- */
.upcoming-classes-list-container {
    display: flex;
    flex-direction: column;
    gap: 15px;
}
/* Thêm vào cuối file style.css */
.booking-counter {
    text-align: center;
    background-color: #e8f5e9;
    color: var(--green);
    padding: 10px;
    border-radius: 8px;
    margin-bottom: 15px;
    font-weight: bold;
    font-size: 1.1rem;
    border: 1px solid var(--green);
}
/* Thêm đoạn này vào CUỐI FILE style.css */
.class-card-action {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
}
.btn-cancel {
    background: transparent;
    color: var(--grey);
    border-color: #d1d5db;
    padding: 8px 18px;
    font-size: 0.9rem;
}
.btn-cancel:hover {
    background: #fee2e2;
    color: #b91c1c;
    border-color: #fecaca;
}
/* Thêm đoạn này vào cuối file style.css */
.cancellation-reason.student-cancelled {
    background-color: #f1f5f9; /* Màu xám nhạt */
    border-left-color: #64748b;
}
.cancellation-reason.student-cancelled i {
    color: #475569;
}
.cancellation-reason.student-cancelled p {
    color: #334155;
}
/* ==================================================
   CHAT WIDGET (STUDENT)
   ================================================== */
.chat-widget-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 60px;
    height: 60px;
    background: var(--green);
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.8rem;
    cursor: pointer;
    box-shadow: 0 5px 20px rgba(58, 125, 36, 0.4);
    z-index: 9998;
    transition: 0.3s;
}
.chat-widget-btn:hover { transform: scale(1.1); }
.chat-widget-badge {
    position: absolute; top: -5px; right: -5px; background: #ef4444; color: white;
    font-size: 0.8rem; font-weight: bold; width: 22px; height: 22px; border-radius: 50%;
    display: flex; justify-content: center; align-items: center; border: 2px solid white; display: none;
}

.chat-window {
    position: fixed; bottom: 90px; right: 20px; width: 350px; height: 500px;
    background: white; border-radius: 20px; box-shadow: 0 10px 40px rgba(0,0,0,0.15);
    z-index: 9999; display: flex; flex-direction: column; overflow: hidden;
    transform: translateY(20px); opacity: 0; pointer-events: none; transition: 0.3s ease;
}
.chat-window.active { transform: translateY(0); opacity: 1; pointer-events: all; }

.chat-win-header {
    background: var(--green); color: white; padding: 15px 20px; display: flex;
    justify-content: space-between; align-items: center; font-weight: bold;
}
.chat-win-body { flex: 1; background: #f9fafb; padding: 15px; overflow-y: auto; display: flex; flex-direction: column; gap: 10px; }
.chat-win-input { padding: 15px; background: white; border-top: 1px solid #eee; display: flex; gap: 10px; }
.chat-win-input input { flex: 1; border: 1px solid #ddd; border-radius: 20px; padding: 10px 15px; outline: none; }
.chat-win-input input:focus { border-color: var(--green); }
.chat-win-input button { background: var(--green); color: white; border: none; width: 40px; height: 40px; border-radius: 50%; cursor: pointer; }

.c-msg { max-width: 80%; padding: 10px 15px; border-radius: 15px; font-size: 0.95rem; line-height: 1.4; position: relative;}
.c-msg-admin { background: white; border: 1px solid #e5e7eb; color: var(--text-dark); align-self: flex-start; border-bottom-left-radius: 5px; }
.c-msg-student { background: var(--green); color: white; align-self: flex-end; border-bottom-right-radius: 5px; }
.c-msg-name { font-size: 0.7rem; font-weight: bold; opacity: 0.6; margin-bottom: 3px; display: block; color: var(--green); }
.c-msg-time { font-size: 0.65rem; opacity: 0.7; margin-top: 4px; display: block; text-align: right;}

/* ==================================================
   GIAO DIỆN CHUYỂN ĐỔI NGÔN NGỮ (LANGUAGE SWITCHER)
   ================================================== */
/* Tìm và thay thế toàn bộ khối CSS cũ bằng đoạn này */
.lang-switcher { position: relative; display: inline-flex; align-items: center; margin-left: 15px; cursor: pointer; padding: 10px 0;}
.lang-btn { background: #f8fafc; border: 2px solid #e5e7eb; padding: 8px 15px; border-radius: 20px; font-weight: bold; color: var(--text-dark); display: flex; align-items: center; gap: 8px; transition: 0.3s; font-size: 0.95rem; }
.lang-btn:hover { border-color: var(--green); color: var(--green); }

.lang-dropdown { 
    display: none; position: absolute; top: 100%; right: 0; 
    background: white; border: 1px solid #e5e7eb; border-radius: 12px; 
    box-shadow: 0 10px 25px rgba(0,0,0,0.1); overflow: hidden; z-index: 101; min-width: 140px; 
}
/* Tạo cầu nối tàng hình để chuột lướt qua không bị mất menu */
.lang-dropdown::before { content: ""; position: absolute; top: -20px; left: 0; right: 0; height: 20px; background: transparent; }

.lang-switcher:hover .lang-dropdown { display: block; animation: fadeIn 0.2s ease; }
.lang-option { padding: 12px 15px; display: flex; align-items: center; gap: 10px; color: var(--text-dark); transition: 0.2s; font-weight: 600; font-size: 0.95rem; }
.lang-option:hover { background: #e8f5e9; color: var(--green); }

/* ==================================================
   MARKDOWN CHAT STYLES
   ================================================== */
.markdown-body p { margin-bottom: 8px; }
.markdown-body p:last-child { margin-bottom: 0; }
.markdown-body strong { font-weight: 800; color: inherit; }
.markdown-body em { font-style: italic; }
.markdown-body ul, .markdown-body ol { margin-left: 20px; margin-bottom: 8px; }
.markdown-body li { margin-bottom: 4px; }
.markdown-body code { background: rgba(0,0,0,0.05); padding: 2px 5px; border-radius: 4px; font-family: monospace; font-size: 0.9em; }
.markdown-body pre { background: #1e293b; color: #f8fafc; padding: 10px; border-radius: 8px; overflow-x: auto; margin-bottom: 8px; }
.markdown-body pre code { background: transparent; padding: 0; color: inherit; }
.msg-user .markdown-body code { background: rgba(255,255,255,0.2); } /* Đổi màu nền code nếu là tin nhắn của user (màu xanh) */
/* Nút bấm nghe lại audio trong tin nhắn AI Speaking */
.msg-audio-btn {
    background: rgba(0,0,0,0.1);
    border: none;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    margin-right: 12px;
    color: inherit;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    transition: 0.2s;
    flex-shrink: 0;
}
.msg-audio-btn:hover { 
    background: rgba(0,0,0,0.2); 
    transform: scale(1.1); 
}
/* ==================================================
   DAILY ACTION WIDGET (BÀI TẬP & GỢI Ý LUYỆN TẬP)
   ================================================== */
.daily-action-wrapper {
    margin-bottom: 25px;
    animation: fadeIn 0.5s ease;
}

/* Kịch bản 1: Có bài tập (Urgent Banner) */
.hw-urgent-banner {
    background: linear-gradient(135deg, #fffbeb 0%, #fef08a 100%);
    border: 1px solid #fde047;
    border-radius: 16px;
    padding: 20px 25px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: 0 8px 20px rgba(250, 204, 21, 0.15);
    transition: 0.3s;
}
.hw-urgent-banner:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(250, 204, 21, 0.25);
}
.hw-urgent-content {
    display: flex;
    align-items: center;
    gap: 20px;
}
.hw-urgent-icon {
    width: 60px;
    height: 60px;
    background: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    color: var(--yellow);
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
}
.hw-urgent-text h3 {
    color: #854d0e;
    font-weight: 900;
    font-size: 1.2rem;
    margin-bottom: 5px;
}
.hw-urgent-text p {
    color: #a16207;
    font-size: 0.95rem;
    margin: 0;
}
.btn-pulse {
    background: var(--green);
    color: white;
    padding: 12px 25px;
    border-radius: 30px;
    font-weight: 800;
    text-decoration: none;
    border: none;
    cursor: pointer;
    box-shadow: 0 0 0 0 rgba(58, 125, 36, 0.7);
    animation: pulse-green 2s infinite;
    transition: 0.3s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
}
.btn-pulse:hover {
    background: #2e661b;
}
@keyframes pulse-green {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(58, 125, 36, 0.7); }
    70% { transform: scale(1); box-shadow: 0 0 0 10px rgba(58, 125, 36, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(58, 125, 36, 0); }
}

/* Kịch bản 2: Không có bài tập (Explore Grid) */
.explore-header {
    text-align: center;
    margin-bottom: 15px;
}
.explore-header h3 {
    color: var(--green);
    font-weight: 800;
    font-size: 1.2rem;
}
.explore-header p {
    color: var(--grey);
    font-size: 0.9rem;
}
.explore-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.explore-card {
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 16px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    transition: 0.3s;
    cursor: pointer;
    text-decoration: none;
    color: inherit;
}
.explore-card:hover {
    transform: translateY(-5px);
    border-color: var(--green);
    box-shadow: 0 10px 20px rgba(58, 125, 36, 0.1);
}
.explore-card.ai-card .explore-icon { background: #f3e8ff; color: #9333ea; }
.explore-card.sing-card .explore-icon { background: #ffe4e6; color: #e11d48; }
.explore-icon {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    margin-bottom: 15px;
}
.explore-card h4 {
    font-weight: 800;
    color: var(--text-dark);
    margin-bottom: 5px;
    font-size: 1.1rem;
}
.explore-card p {
    font-size: 0.85rem;
    color: var(--grey);
    margin-bottom: 15px;
    line-height: 1.4;
    flex: 1;
}
.explore-card span {
    font-weight: bold;
    font-size: 0.9rem;
}
.explore-card.ai-card span { color: #9333ea; }
.explore-card.sing-card span { color: #e11d48; }

/* Responsive */
@media (max-width: 768px) {
    .hw-urgent-banner { flex-direction: column; text-align: center; gap: 20px; }
    .hw-urgent-content { flex-direction: column; }
    .explore-grid { grid-template-columns: 1fr; }
}
/* ==================================================
   LEGAL PAGES & FOOTER (PRIVACY / TERMS)
   ================================================== */
.legal-doc h3 {
    color: var(--green);
    margin-top: 25px;
    margin-bottom: 10px;
    font-size: 1.2rem;
    font-weight: 800;
}
.legal-doc p, .legal-doc li {
    color: var(--text-dark);
    line-height: 1.7;
    margin-bottom: 10px;
    font-size: 1rem;
}
.legal-doc ul {
    margin-left: 20px;
    margin-bottom: 15px;
}
.contact-box {
    background: #f8fafc;
    border-left: 4px solid var(--yellow);
    padding: 15px 20px;
    border-radius: 8px;
    margin-top: 15px;
}

/* Global Footer */
.site-footer {
    background: var(--white);
    border-top: 1px solid #e5e7eb;
    padding: 40px 20px 20px 20px;
    margin-top: 50px;
}
.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 30px;
}
.footer-brand h2 {
    color: var(--green);
    font-weight: 900;
    margin-bottom: 10px;
}
.footer-brand p {
    color: var(--grey);
    font-size: 0.9rem;
    line-height: 1.5;
    max-width: 300px;
}
.footer-links h4 {
    color: var(--text-dark);
    margin-bottom: 15px;
    font-size: 1.1rem;
}
.footer-links a {
    display: block;
    color: var(--grey);
    text-decoration: none;
    margin-bottom: 10px;
    font-weight: bold;
    transition: 0.3s;
}
.footer-links a:hover {
    color: var(--green);
}
.footer-contact p {
    color: var(--text-dark);
    margin-bottom: 10px;
    font-size: 0.95rem;
}
.footer-contact i {
    color: var(--green);
    width: 20px;
}
.footer-bottom {
    max-width: 1200px;
    margin: 30px auto 0 auto;
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #e5e7eb;
    color: var(--grey);
    font-size: 0.85rem;
}
/* ==================================================
   GLOBAL LOADING OVERLAY (Chống Spam Click)
   ================================================== */
.global-overlay {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(3px);
    z-index: 99999; /* Đảm bảo nằm trên mọi thứ */
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
.global-overlay.active {
    display: flex;
}
.global-overlay-spinner {
    font-size: 3rem;
    color: var(--green);
    margin-bottom: 15px;
    animation: spin 1s linear infinite;
}
.global-overlay-text {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--text-dark);
}
@keyframes spin { 100% { transform: rotate(360deg); } }
/* --- CSS MỚI CHO CARD CÓ VIDEO THUMBNAIL --- */
.video-course-card {
    position: relative;
    background-size: cover;
    background-position: center;
    overflow: hidden;
    border: none; /* Bỏ viền mặc định để ảnh tràn viền đẹp hơn */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 30px 20px;
}

/* Lớp phủ Gradient đen mờ giúp chữ nổi bật trên nền ảnh */
.video-course-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(to bottom, rgba(0,0,0,0.3) 0%, rgba(0,0,0,0.8) 100%);
    z-index: 1;
    transition: 0.4s;
}

/* Khi hover, làm lớp phủ tối thêm một chút và hiệu ứng nảy */
.video-course-card:hover::before {
    background: linear-gradient(to bottom, rgba(0,0,0,0.5) 0%, rgba(0,0,0,0.9) 100%);
}

/* Đưa nội dung (Icon, Text) nổi lên trên lớp phủ */
.video-course-card .content-z {
    position: relative;
    z-index: 2;
}

/* Hiệu ứng cho nút Play bên trong */
.video-course-card .content-z i {
    color: var(--yellow) !important;
    filter: drop-shadow(0 4px 10px rgba(0,0,0,0.5));
    transition: 0.3s;
}

.video-course-card:hover .content-z i {
    transform: scale(1.15);
    color: #fff !important;
}

.video-course-card h3 {
    color: #ffffff;
    text-shadow: 0 2px 5px rgba(0,0,0,0.8);
}

.video-course-card p {
    color: #e5e7eb;
    text-shadow: 0 1px 3px rgba(0,0,0,0.8);
}
/* ==================================================
   GIAO DIỆN CHUYỂN KHOẢN NGÂN HÀNG (VIETQR)
   ================================================== */
.bank-transfer-box {
    background: #f8fafc;
    border: 2px solid #e5e7eb;
    border-radius: 16px;
    padding: 25px 20px;
    text-align: center;
    margin-top: 15px;
    animation: fadeIn 0.4s ease;
}
.qr-image-wrapper {
    background: white;
    padding: 15px;
    border-radius: 12px;
    display: inline-block;
    border: 2px dashed var(--green);
    margin-bottom: 20px;
}
.qr-image-wrapper img {
    max-width: 220px;
    height: auto;
    border-radius: 8px;
}
.bank-info-list {
    background: white;
    border-radius: 12px;
    border: 1px solid #e5e7eb;
    padding: 0 15px;
    margin-bottom: 20px;
}
.bank-info-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px dashed #e5e7eb;
}
.bank-info-row:last-child {
    border-bottom: none;
}
.bank-info-label {
    color: var(--grey);
    font-size: 0.9rem;
    text-align: left;
}
.bank-info-value {
    font-weight: 800;
    color: var(--text-dark);
    font-size: 1rem;
    text-align: right;
    display: flex;
    align-items: center;
    gap: 10px;
}
.copy-btn {
    background: #e0e7ff;
    color: #4f46e5;
    border: none;
    width: 30px;
    height: 30px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: 0.2s;
    display: flex;
    justify-content: center;
    align-items: center;
}
.copy-btn:hover {
    background: #4f46e5;
    color: white;
    transform: scale(1.1);
}
.bank-disclaimer {
    font-size: 0.85rem;
    color: #854d0e;
    background: #fefce8;
    padding: 12px;
    border-radius: 8px;
    border-left: 4px solid #facc15;
    margin-bottom: 20px;
    text-align: left;
    line-height: 1.5;
}