/* =====================================================
   THITHU - GIAO DIỆN GIỐNG PHẦN MỀM BỘ
   Thiết kế: GTVT blue theme, Arial, 3 màn
   v3.6.3 — 2026-09-15: Mobile scroll fix.
                          - BỎ nested scroll .exam-options (chỉ .exam-left cuộn)
                          - Giảm padding option 12/14 → 9/12, min-height 52 → 46
                          - Câu hỏi font 19 → 16, padding gọn
                          - Ảnh max-height 38vh → 28vh, có max-height cả <img>
                          - Tránh "đáp án bị che dưới" do 2 scroll container chồng
   v3.6.4 — 2026-09-15: Last-word override .exam-options overflow.
                          - Rule 20260909-fix ở giữa file set overflow-y:auto
                            trên .exam-options gây nested scroll → user không
                            vuốt xem được đáp án dài.
                          - Block cuối file (same specificity + !important, sau hơn)
                            set overflow-y:visible trên .exam-options để CHỈ
                            .exam-left mới cuộn.
   v3.6.6 — 2026-09-15: Cleanup CSS mobile — XÓA 7 media query blocks duplicate.
                          - Xóa block @media (max-width:480px) cũ set height:auto
                            trên .exam-body (PHÁ HỎNG scroll).
                          - Xóa block @media (max-width:768px) duplicate.
                          - Xóa 3 block @media (max-width:991px) duplicate.
                          - GIỮ block @media (max-width:991px) duy nhất (line 1022)
                            với tất cả rules mobile cần thiết.
                          - File giảm từ 2593 → 1839 dòng.
   ===================================================== */

* { margin: 0; padding: 0; box-sizing: border-box; }
html, body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Helvetica, Arial, sans-serif;
    background: #D8D8D8;
    color: #212121;
    min-height: 100%;
    font-size: 14px;
    overflow-x: hidden;
    /* safe-area variables */
    --sat: env(safe-area-inset-top, 0px);
    --sab: env(safe-area-inset-bottom, 0px);
    --sal: env(safe-area-inset-left, 0px);
    --sar: env(safe-area-inset-right, 0px);
}
button { font-family: inherit; cursor: pointer; }
input, select { font-family: inherit; }

/* ===== MÀU SẮC SÁT HẠCH BỘ ===== */
:root {
    --bo-blue:     #1565C0;
    --bo-blue-d:   #0D47A1;
    --bo-blue-l:   #1E88E5;
    --bo-blue-p:   #E3F2FD;
    --bo-green:    #388E3C;
    --bo-green-l:  #4CAF50;
    --bo-green-p:  #E8F5E9;
    --bo-red:      #C62828;
    --bo-red-l:    #EF5350;
    --bo-red-p:    #FFEBEE;
    --bo-yellow:   #FFD600;
    --bo-orange:   #EF6C00;
    --bo-gray:     #ECEFF1;
    --bo-gray2:    #B0BEC5;
    --bo-gray3:    #78909C;
    --bo-text:     #212121;
    --bo-text2:    #37474F;
    --bo-text3:    #607D8B;
}

/* ===== APP LAYOUT (full viewport) ===== */
.app {
    display: grid;
    grid-template-rows: 52px 1fr auto;
    height: 100%;
    height: 100dvh;
    width: 100%;
    max-width: 100vw;
    padding-bottom: var(--sab, 0px);
}

/* ===== HEADER (giống phần mềm Bộ) ===== */
.app-header {
    background: var(--bo-blue);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 12px;
    border-bottom: 2px solid var(--bo-blue-d);
    flex-shrink: 0;
}
.app-header .hdr-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #fff;
}
.app-header .hdr-logo-icon {
    width: 34px; height: 34px;
    background: var(--bo-yellow);
    border-radius: 4px;
    display: flex; align-items: center; justify-content: center;
    font-size: 17px; font-weight: 700; color: #1565C0;
    flex-shrink: 0;
}
.app-header .hdr-logo-text {
    font-size: 11px; line-height: 1.2;
}
.app-header .hdr-logo-text strong {
    display: block; font-size: 12px;
}
.app-header .hdr-title {
    color: #fff; font-size: 13px; font-weight: 700;
    letter-spacing: 1px;
}
.app-header .hdr-hang {
    background: #fff; color: var(--bo-blue);
    border: 1.5px solid var(--bo-yellow);
    padding: 5px 14px; font-size: 13px; font-weight: 700;
    border-radius: 3px; min-width: 90px; text-align: center;
}

/* ===== APP BODY (setup / exam) ===== */
.app-body {
    overflow: hidden;
    position: relative;
}

/* ===== SETUP SCREEN (màn đầu - giống Bộ) ===== */
#setupScreen {
    display: flex;
    height: 100%;
    background: #fff;
}

.setup-left {
    width: 200px;
    background: var(--bo-blue);
    border-right: 3px solid var(--bo-blue-d);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
}

.setup-menu {
    padding: 10px 0;
    flex: 1;
}
.setup-menu-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    color: rgba(255,255,255,0.75);
    font-size: 12px;
    font-weight: 400;
    border: none;
    background: transparent;
    width: 100%;
    text-align: left;
    cursor: pointer;
    border-left: 3px solid transparent;
    transition: all 0.15s;
}
.setup-menu-item .menu-icon {
    font-size: 16px; width: 22px; text-align: center; flex-shrink: 0;
}
.setup-menu-item:hover {
    background: rgba(255,255,255,0.08);
    color: #fff;
}
.setup-menu-item.active {
    background: rgba(255,255,255,0.15);
    color: #fff;
    font-weight: 700;
    border-left-color: var(--bo-yellow);
}

.setup-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}
.setup-topbar {
    background: var(--bo-gray);
    border-bottom: 1px solid var(--bo-gray2);
    padding: 8px 16px;
    font-size: 12px; color: var(--bo-text3);
    display: flex; align-items: center; gap: 6px;
    flex-shrink: 0;
}
.setup-topbar span { color: var(--bo-text2); font-weight: 700; }

.setup-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px 20px;
}

.setup-section-title {
    font-size: 12px;
    font-weight: 700;
    color: var(--bo-text2);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 10px;
    padding-bottom: 6px;
    border-bottom: 2px solid var(--bo-blue);
    display: inline-block;
}

/* Grid hạng thi */
.hang-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 6px;
    max-width: 560px;
}
.hang-cell {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 9px 12px;
    background: var(--bo-gray);
    border: 1.5px solid var(--bo-gray2);
    cursor: pointer;
    font-size: 13px;
    transition: all 0.15s;
    border-radius: 2px;
}
.hang-cell:hover { border-color: var(--bo-blue); background: var(--bo-blue-p); }
.hang-cell.selected {
    background: var(--bo-blue);
    border-color: var(--bo-blue-d);
    color: #fff;
}
.hang-cell .hang-code {
    font-weight: 700; font-size: 14px; min-width: 36px;
}
.hang-cell .hang-desc { font-size: 11px; opacity: 0.8; }

/* Setup info panel */
.setup-info {
    margin-top: 20px;
    padding: 14px;
    background: var(--bo-blue-p);
    border: 1px solid var(--bo-blue-l);
    border-radius: 2px;
}
.setup-info-row {
    display: flex; gap: 20px; flex-wrap: wrap;
    font-size: 12px; margin-bottom: 6px;
}
.setup-info-row:last-child { margin-bottom: 0; }
.setup-info-label { color: var(--bo-text3); font-weight: 700; min-width: 100px; }
.setup-info-value { color: var(--bo-text); font-weight: 700; }

/* Begin button */
.setup-actions {
    padding: 12px 16px;
    background: #fff;
    border-top: 2px solid var(--bo-gray2);
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    flex-shrink: 0;
}
.btn-bo {
    padding: 10px 24px;
    font-size: 13px;
    font-weight: 700;
    border-radius: 3px;
    border: 1.5px solid;
    letter-spacing: 0.5px;
    cursor: pointer;
    transition: all 0.15s;
}
.btn-bo-secondary {
    background: #fff;
    color: var(--bo-text2);
    border-color: var(--bo-gray2);
}
.btn-bo-secondary:hover { border-color: var(--bo-blue); color: var(--bo-blue); }
.btn-bo-primary {
    background: var(--bo-green);
    color: #fff;
    border-color: var(--bo-green);
}
.btn-bo-primary:hover { background: var(--bo-green-l); border-color: var(--bo-green-l); }

/* ===== CANDIDATE FORM MODAL ===== */
.modal-overlay {
    position: fixed; inset: 0;
    background: rgba(0,0,0,0.55);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}
.modal-overlay.active { display: flex; }

.modal {
    background: #fff;
    border: 3px solid var(--bo-blue);
    width: 520px;
    max-width: 98vw;
    border-radius: 3px;
    box-shadow: 0 8px 40px rgba(0,0,0,0.25);
}
.modal-hdr {
    background: var(--bo-blue);
    color: #fff;
    padding: 10px 14px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.modal-hdr-icon {
    width: 30px; height: 30px;
    background: var(--bo-yellow);
    border-radius: 3px;
    display: flex; align-items: center; justify-content: center;
    font-size: 15px; font-weight: 700; color: #1565C0;
    flex-shrink: 0;
}
.modal-hdr-text strong {
    display: block; font-size: 14px; letter-spacing: 0.5px;
}
.modal-hdr-text small {
    font-size: 10px; opacity: 0.8;
}
.modal-close-btn {
    margin-left: auto;
    background: rgba(255,255,255,0.2);
    color: #fff;
    border: none;
    width: 26px; height: 26px;
    font-size: 16px; font-weight: 700;
    border-radius: 2px;
    cursor: pointer;
}
.modal-close-btn:hover { background: rgba(255,255,255,0.35); }

.modal-body { padding: 16px; }
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-bottom: 10px;
}
.form-group { margin-bottom: 10px; }
.form-group:last-child { margin-bottom: 0; }
.form-label {
    display: block;
    font-size: 11px;
    font-weight: 700;
    color: var(--bo-text2);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
}
.form-label .req { color: var(--bo-red); }
.form-input {
    width: 100%;
    padding: 8px 10px;
    border: 1px solid var(--bo-gray2);
    background: #fff;
    font-size: 14px;
    outline: none;
    border-radius: 2px;
}
.form-input:focus {
    border-color: var(--bo-blue);
    box-shadow: 0 0 0 2px var(--bo-blue-p);
}

/* Grid hạng trong modal */
.hang-grid-modal {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 3px;
}
.hang-btn-modal {
    padding: 7px 4px;
    background: var(--bo-gray);
    color: var(--bo-text2);
    border: 1.5px solid var(--bo-gray2);
    font-size: 12px;
    font-weight: 700;
    text-align: center;
    cursor: pointer;
    border-radius: 2px;
    transition: all 0.15s;
}
.hang-btn-modal:hover { border-color: var(--bo-blue); color: var(--bo-blue); }
.hang-btn-modal.selected {
    background: var(--bo-blue);
    color: #fff;
    border-color: var(--bo-blue-d);
}

.modal-foot {
    padding: 12px 16px;
    background: var(--bo-gray);
    border-top: 1px solid var(--bo-gray2);
    display: flex;
    justify-content: center;
    gap: 10px;
}
.btn-submit-exam {
    padding: 10px 32px;
    background: var(--bo-green);
    color: #fff;
    border: 2px solid var(--bo-green);
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 1px;
    border-radius: 3px;
    cursor: pointer;
    transition: all 0.15s;
}
.btn-submit-exam:hover { background: var(--bo-green-l); border-color: var(--bo-green-l); }

/* ===== EXAM SCREEN ===== */
#examScreen {
    display: none;
    height: 100dvh;
    max-height: 100dvh;
    width: 100%;
    max-width: 100vw;
    grid-template-rows: 1fr auto;
    overflow: hidden;
}

/* Exam body = câu hỏi + sidebar */
.exam-body {
    display: grid;
    grid-template-columns: 1fr 220px;
    overflow: hidden;
}

/* Câu hỏi */
.exam-left {
    padding: 12px 16px;
    overflow-y: auto;
    background: #fff;
}
.exam-q-hdr {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 6px 10px;
    background: var(--bo-blue-p);
    border: 1px solid var(--bo-blue-l);
    margin-bottom: 8px;
    border-radius: 2px;
}
.exam-q-num {
    font-weight: 700; font-size: 14px; color: var(--bo-blue);
}
.exam-critical-badge {
    background: var(--bo-red);
    color: #fff;
    font-size: 10px;
    font-weight: 700;
    padding: 2px 6px;
    border-radius: 2px;
    letter-spacing: 0.5px;
}
.exam-q-text {
    font-size: 15px;
    line-height: 1.55;
    color: var(--bo-text);
    margin-bottom: 10px;
    font-weight: 400;
    padding: 0 4px;
}
.exam-q-img {
    display: block;
    max-width: 100%;
    max-height: 240px;
    margin: 8px auto 12px;
    border: 1px solid var(--bo-gray2);
    border-radius: 2px;
}
.exam-options {
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.exam-opt {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 12px;
    background: var(--bo-gray);
    border: 1.5px solid var(--bo-gray2);
    cursor: pointer;
    border-radius: 2px;
    transition: all 0.12s;
}
.exam-opt:hover { border-color: var(--bo-blue-l); background: var(--bo-blue-p); }
.exam-opt.selected {
    background: var(--bo-blue-p);
    border: 2px solid var(--bo-blue);
    padding: 9px 11px;
}
.exam-opt.focused {
    /* Chỉ dùng khi điều hướng bằng bàn phím – khác rõ với selected */
    border-color: var(--bo-blue);
    border-style: dashed;
    background: #fff;
    outline: none;
}
.exam-opt-key {
    width: 24px; height: 24px;
    background: #fff;
    border: 1.5px solid var(--bo-gray2);
    border-radius: 2px;
    display: flex; align-items: center; justify-content: center;
    font-size: 12px; font-weight: 700; color: var(--bo-text2);
    flex-shrink: 0;
}
.exam-opt.selected .exam-opt-key {
    background: var(--bo-blue);
    border-color: var(--bo-blue-d);
    color: #fff;
}
.exam-opt-text {
    font-size: 14px;
    line-height: 1.45;
    color: var(--bo-text);
}

/* Exam navigation — fixed, luôn bấm được trên mọi máy */
.exam-nav {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 100;
    padding: 10px 10px 0;
    /* Đệm cứng tối thiểu ~48px cho thanh 3 nút Android + safe-area */
    padding-bottom: calc(12px + max(env(safe-area-inset-bottom, 0px), 0px) + var(--nav-extra, 48px));
    background: #fff;
    border-top: 1px solid var(--bo-gray2);
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
    box-shadow: 0 -6px 20px rgba(0,0,0,.12);
    max-width: 100vw;
}
.exam-nav-btn {
    padding: 7px 14px;
    border-radius: 2px;
    font-size: 12px;
    font-weight: 700;
    cursor: pointer;
    border: 1.5px solid;
    transition: all 0.15s;
}
.exam-nav-prev {
    background: #fff; color: var(--bo-text2); border-color: var(--bo-gray2);
}
.exam-nav-prev:hover { border-color: var(--bo-blue); color: var(--bo-blue); }
.exam-nav-prev:disabled { opacity: 0.4; cursor: not-allowed; }
.exam-nav-next {
    background: var(--bo-blue); color: #fff; border-color: var(--bo-blue);
    margin-left: auto;
}
.exam-nav-next:hover { background: var(--bo-blue-l); border-color: var(--bo-blue-l); }
.exam-flag-btn {
    padding: 7px 12px;
    background: #fff;
    color: var(--bo-orange);
    border: 1.5px solid var(--bo-orange);
    font-size: 12px; font-weight: 700;
    border-radius: 2px;
    cursor: pointer;
    transition: all 0.15s;
}
.exam-flag-btn:hover, .exam-flag-btn.flagged {
    background: var(--bo-orange); color: #fff;
}
.exam-finish-btn {
    padding: 7px 14px;
    background: var(--bo-green);
    color: #fff;
    border: 1.5px solid var(--bo-green);
    font-size: 12px; font-weight: 700;
    border-radius: 2px;
    cursor: pointer;
    transition: all 0.15s;
}
.exam-finish-btn:hover { background: var(--bo-green-l); border-color: var(--bo-green-l); }

/* Exam sidebar */
.exam-sidebar {
    background: var(--bo-gray);
    border-left: 2px solid var(--bo-gray2);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}
.sidebar-timer {
    padding: 10px;
    text-align: center;
    background: #fff;
    border-bottom: 1px solid var(--bo-gray2);
}
.sidebar-timer-label {
    font-size: 10px;
    font-weight: 700;
    color: var(--bo-text3);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 4px;
}
.sidebar-timer-val {
    font-size: 26px;
    font-weight: 700;
    color: var(--bo-green);
    font-variant-numeric: tabular-nums;
    letter-spacing: 2px;
}
.sidebar-timer-val.warn { color: var(--bo-orange); }
.sidebar-timer-val.danger { color: var(--bo-red); }

.sidebar-qnav {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
}
.sidebar-qnav-title {
    font-size: 10px; font-weight: 700;
    color: var(--bo-text3);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 6px;
    text-align: center;
}
.sidebar-qnav-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 4px;
}
.sidebar-qnav-cell {
    aspect-ratio: 1;
    display: flex; align-items: center; justify-content: center;
    font-size: 11px; font-weight: 700;
    background: #fff;
    border: 1.5px solid var(--bo-gray2);
    cursor: pointer;
    border-radius: 2px;
    transition: all 0.1s;
    color: var(--bo-text2);
}
.sidebar-qnav-cell:hover { border-color: var(--bo-blue); }
.sidebar-qnav-cell.answered { background: var(--bo-blue); color: #fff; border-color: var(--bo-blue-d); }
.sidebar-qnav-cell.current { background: var(--bo-yellow); color: #1565C0; border-color: #F9A825; font-weight: 800; }
.sidebar-qnav-cell.flagged { background: var(--bo-orange); color: #fff; border-color: #E65100; }

.sidebar-legend {
    padding: 8px 10px;
    background: #fff;
    border-top: 1px solid var(--bo-gray2);
    font-size: 10px;
    color: var(--bo-text3);
}
.sidebar-legend-row {
    display: flex; align-items: center; gap: 6px; margin-bottom: 4px;
}
.sidebar-legend-row:last-child { margin-bottom: 0; }
.sidebar-legend-dot {
    width: 12px; height: 12px;
    border: 1.5px solid var(--bo-gray2);
    border-radius: 2px;
    flex-shrink: 0;
}
.sidebar-legend-dot.answered { background: var(--bo-blue); border-color: var(--bo-blue-d); }
.sidebar-legend-dot.current { background: var(--bo-yellow); border-color: #F9A825; }
.sidebar-legend-dot.flagged { background: var(--bo-orange); border-color: #E65100; }

.sidebar-critical-warn {
    padding: 8px 10px;
    background: var(--bo-red-p);
    border-top: 2px solid var(--bo-red);
    text-align: center;
}
.sidebar-critical-warn strong {
    font-size: 10px; color: var(--bo-red); display: block;
}
.sidebar-critical-warn div {
    font-size: 10px; color: var(--bo-red); margin-top: 2px;
}

/* ===== EXAM FOOTER ===== */
.exam-footer {
    background: #fff;
    border-top: 2px solid var(--bo-gray2);
    display: flex;
    align-items: center;
    padding: 0 12px;
    gap: 12px;
}
.exam-footer-candidate {
    display: flex; align-items: center; gap: 10px;
    font-size: 12px; color: var(--bo-text2);
}
.exam-footer-candidate .avatar {
    width: 30px; height: 30px;
    background: var(--bo-blue);
    border-radius: 2px;
    display: flex; align-items: center; justify-content: center;
    color: #fff; font-size: 14px;
}
.exam-footer-info {
    display: flex; gap: 14px; font-size: 11px; flex-wrap: wrap;
}
.exam-footer-info .fi { display: flex; gap: 4px; }
.exam-footer-info .fi-lbl { color: var(--bo-text3); font-weight: 700; }
.exam-footer-info .fi-val { color: var(--bo-text2); font-weight: 700; }
.exam-footer-right {
    margin-left: auto;
    display: flex; align-items: center; gap: 14px;
}
.exam-progress {
    display: flex; align-items: center; gap: 6px;
    font-size: 12px; color: var(--bo-text2);
}
.exam-progress .prog-lbl { font-weight: 700; color: var(--bo-text3); font-size: 11px; }
.exam-progress .prog-val { font-weight: 700; color: var(--bo-blue); font-size: 14px; }

/* ===== SUBMIT CONFIRM MODAL ===== */
.submit-modal .modal {
    width: 380px;
}
.submit-modal .modal-body {
    padding: 20px;
    text-align: center;
}
.submit-modal .submit-msg {
    font-size: 14px;
    color: var(--bo-text);
    margin-bottom: 8px;
}
.submit-modal .submit-msg strong {
    font-size: 16px;
    color: var(--bo-blue);
}
.submit-modal .submit-warn {
    font-size: 13px;
    color: var(--bo-red);
    margin-top: 10px;
}
.submit-modal .submit-actions {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin-top: 16px;
}
.submit-modal .btn-cancel {
    padding: 9px 24px;
    background: #fff;
    color: var(--bo-text2);
    border: 1.5px solid var(--bo-gray2);
    font-size: 13px; font-weight: 700;
    border-radius: 3px; cursor: pointer;
}
.submit-modal .btn-cancel:hover { border-color: var(--bo-blue); color: var(--bo-blue); }
.submit-modal .btn-confirm {
    padding: 9px 24px;
    background: var(--bo-green);
    color: #fff;
    border: 1.5px solid var(--bo-green);
    font-size: 13px; font-weight: 700;
    border-radius: 3px; cursor: pointer;
}
.submit-modal .btn-confirm:hover { background: var(--bo-green-l); border-color: var(--bo-green-l); }

/* ===== RESULT MODAL ===== */
.result-modal .modal {
    width: 520px;
    max-height: 95vh;
    overflow-y: auto;
}
.result-banner {
    background: var(--bo-blue);
    padding: 10px 16px;
    display: flex; align-items: center; gap: 10px;
    border-bottom: 2px solid var(--bo-blue-d);
}
.result-banner-icon {
    width: 36px; height: 36px;
    background: var(--bo-yellow);
    border-radius: 4px;
    display: flex; align-items: center; justify-content: center;
    font-size: 18px; font-weight: 700; color: #1565C0;
    flex-shrink: 0;
}
.result-banner-text strong {
    display: block; color: #fff; font-size: 13px; letter-spacing: 0.5px;
}
.result-banner-text small { color: rgba(255,255,255,0.8); font-size: 10px; }
.result-title-bar {
    padding: 10px 16px;
    background: var(--bo-gray);
    border-bottom: 1px solid var(--bo-gray2);
    font-size: 12px; color: var(--bo-text3);
}
.result-title-bar h3 {
    font-size: 14px; font-weight: 700;
    color: var(--bo-blue); letter-spacing: 0.5px;
}
.result-info-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}
.result-info-table td {
    padding: 6px 16px;
    border-bottom: 1px solid var(--bo-gray);
}
.result-info-table td:first-child {
    color: var(--bo-text3);
    font-weight: 700;
    width: 42%;
}
.result-info-table td:last-child { color: var(--bo-text); }
.result-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    padding: 12px 16px;
}
.result-stat {
    text-align: center;
    padding: 10px;
    border-radius: 3px;
    border: 1.5px solid;
}
.result-stat.correct { background: var(--bo-green-p); border-color: var(--bo-green); }
.result-stat.wrong   { background: var(--bo-red-p);   border-color: var(--bo-red); }
.result-stat.blank    { background: var(--bo-gray);    border-color: var(--bo-gray2); }
.result-stat-val {
    font-size: 24px; font-weight: 700; display: block;
}
.result-stat.correct .result-stat-val { color: var(--bo-green); }
.result-stat.wrong   .result-stat-val { color: var(--bo-red); }
.result-stat.blank   .result-stat-val { color: var(--bo-text3); }
.result-stat-lbl { font-size: 11px; font-weight: 700; color: var(--bo-text3); display: block; margin-top: 2px; }
.result-verdict {
    margin: 0 16px 12px;
    padding: 12px;
    border-radius: 3px;
    text-align: center;
    border: 2px solid;
}
.result-verdict.pass {
    background: var(--bo-green-p);
    border-color: var(--bo-green);
}
.result-verdict.fail {
    background: var(--bo-red-p);
    border-color: var(--bo-red);
}
.result-verdict-lbl {
    font-size: 10px; font-weight: 700;
    color: var(--bo-text3); text-transform: uppercase; letter-spacing: 1px;
}
.result-verdict-val {
    font-size: 22px; font-weight: 700; display: block;
}
.result-verdict.pass .result-verdict-val { color: var(--bo-green); }
.result-verdict.fail .result-verdict-val { color: var(--bo-red); }
.result-verdict-note {
    font-size: 11px; color: var(--bo-red); margin-top: 4px;
    display: none;
}
.result-verdict-detail {
    font-size: 11px; color: var(--bo-text3); margin-top: 4px;
}
.result-actions {
    display: flex; gap: 8px; justify-content: center;
    padding: 12px 16px;
    border-top: 1px solid var(--bo-gray);
}
.result-action {
    padding: 8px 16px;
    border-radius: 3px;
    font-size: 12px; font-weight: 700;
    cursor: pointer; border: 1.5px solid;
    display: flex; align-items: center; gap: 6px;
    transition: all 0.15s;
}
.result-action.print {
    background: var(--bo-blue); color: #fff; border-color: var(--bo-blue);
}
.result-action.print:hover { background: var(--bo-blue-l); }
.result-action.score {
    background: #fff; color: var(--bo-text2); border-color: var(--bo-gray2);
}
.result-action.score:hover { border-color: var(--bo-blue); color: var(--bo-blue); }
.result-action.exit {
    background: #fff; color: var(--bo-red); border-color: var(--bo-red);
}
.result-action.exit:hover { background: var(--bo-red); color: #fff; }
.result-footer {
    padding: 8px 16px;
    background: var(--bo-gray);
    border-top: 1px solid var(--bo-gray2);
    font-size: 11px;
    color: var(--bo-text3);
    text-align: center;
}

/* ===== MISC ===== */
.hidden { display: none !important; }
.print-only { display: none; }

/* ===== RESPONSIVE ===== */
@media (max-width: 900px) {
    .exam-body { grid-template-columns: 1fr; }
    .exam-sidebar { display: none; }
    .hang-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
    .setup-left { width: 50px; }
    .setup-menu-item .menu-icon { font-size: 18px; }
    .setup-menu-item span:not(.menu-icon) { display: none; }
    .form-row { grid-template-columns: 1fr; }
    .hang-grid-modal { grid-template-columns: repeat(4, 1fr); }
}

/* Mobile tối ưu (thiết bị thật) */

/* Safe area cho notch / gesture bar / home indicator */
@supports (padding: max(0px)) {
    .exam-nav {
        padding-bottom: calc(16px + env(safe-area-inset-bottom, 0px) + var(--nav-extra, 52px));
    }
    .exam-footer {
        padding-bottom: max(16px, calc(12px + env(safe-area-inset-bottom, 0px)));
    }
    .modal-foot {
        padding-bottom: max(16px, calc(12px + env(safe-area-inset-bottom, 0px)));
    }
    .app-header {
        padding-top: max(0px, env(safe-area-inset-top, 0px));
    }
}

/* Desktop: nav không cần fixed */
@media (min-width: 900px) {
    .exam-nav {
        position: relative;
        left: auto; right: auto; bottom: auto;
        padding-bottom: 12px;
        box-shadow: none;
    }
    .exam-body {
        padding-bottom: 0;
    }
    #examScreen {
        grid-template-rows: 1fr auto;
    }
}


/* Fallback thêm cho máy Android không khai báo safe-area */
@media (max-width: 900px) {
    .exam-nav {
        padding-bottom: calc(14px + env(safe-area-inset-bottom, 0px) + 6px);
    }
}

/* Touch target tối thiểu 44px */
.exam-opt, .exam-nav-btn, .exam-flag-btn, .exam-finish-btn,
.hang-cell, .btn-bo, .result-action, .modal-close-btn,
.form-input, .btn-submit-exam, .btn-confirm, .btn-cancel {
    touch-action: manipulation;
    -webkit-tap-highlight-color: rgba(21, 101, 192, 0.15);
}

/* Ngăn double-tap zoom */
button, a, .exam-opt, .hang-cell {
    touch-action: manipulation;
}

/* Mode buttons */
.mode-btn {
    border: 1.5px solid #CFD8DC;
    background: #fff;
    border-radius: 12px;
    padding: 12px 10px;
    cursor: pointer;
    text-align: left;
    transition: all .15s;
}
.mode-btn strong { display: block; font-size: 14px; margin-bottom: 2px; color: #212121; }
.mode-btn small { font-size: 11px; color: #78909C; }
.mode-btn.active {
    border-color: #1565C0;
    background: #E3F2FD;
    box-shadow: 0 0 0 1px #1565C0;
}
.mode-btn.active strong { color: #1565C0; }

.exam-opt.correct {
    border-color: #2E7D32 !important;
    background: #E8F5E9 !important;
}
.exam-opt.wrong {
    border-color: #C62828 !important;
    background: #FFEBEE !important;
}

/* ==========================================================================
   MOBILE-FIRST APP-NATIVE LAYOUT (<= 768px)
   Chuẩn 100% hình mẫu — 4 KHỐI NO-SCROLL
   ========================================================================== */
@media (max-width: 991px) {

    /* ===== 1. NO-SCROLL CHỈ KHI ĐANG THI — KHÔNG khóa trang chọn đề ===== */
    body.exam-active {
        margin: 0;
        padding: 0;
        height: 100dvh;
        overflow: hidden; /* Ngăn cuộn toàn trang — KHÔNG position:fixed (chặn touch) */
        touch-action: manipulation;
    }

    /* Khung màn hình làm bài — CHỈ hiện khi đã bắt đầu thi */
    #examScreen {
        display: none;
        height: 100dvh;
        max-height: 100dvh;
        flex-direction: column;
        overflow: hidden;
    }
    #examScreen.is-on,
    #examScreen.exam-visible,
    body.exam-active #examScreen {
        display: flex !important;
    }

    /* ===== 2. ẨN TOÀN BỘ PHẦN RƯỜM RÀ ===== */
    .app-header,
    .app-header *,
    .qnav-card,
    .qnav-card *,
    .exam-progress-bar,
    .exam-progress-bar *,
    .exam-timer,
    .qnav-legend,
    .qnav-legend * { display: none !important; }

    /* ===== 3. EXAM SCREEN — full viewport flex column 4 khối ===== */
    #examScreen.is-on,
    #examScreen.exam-visible,
    body.exam-active #examScreen {
        height: 100dvh !important;
        max-height: 100dvh !important;
        display: flex !important;
        flex-direction: column !important;
        overflow: hidden !important;
        padding: 0 !important;
        margin: 0 !important;
        background: #fff;
        position: fixed;
        inset: 0;
        width: 100%;
        z-index: 80;
    }

    /* ===== 4. KHỐI 1: HEADER (44px cố định) ===== */
    .exam-app-header {
        display: flex !important;
        align-items: center;
        justify-content: space-between;
        padding: 0 10px;
        height: 44px;
        background: #fff;
        border-bottom: 1.5px solid #e2e8f0;
        flex-shrink: 0;
        z-index: 200;
        position: relative;
        gap: 6px;
        padding-top: max(env(safe-area-inset-top, 0px), 0px);
    }
    .exam-app-header.hidden { display: none !important; }

    .exam-app-timer {
        font-size: 20px;
        font-weight: 700;
        color: #1e293b;
        white-space: nowrap;
        min-width: 60px;
        font-variant-numeric: tabular-nums;
        letter-spacing: 0.2px;
    }
    .exam-app-timer.urgent {
        color: #dc2626;
        animation: timer-pulse 1s infinite;
    }
    @keyframes timer-pulse {
        0%, 100% { opacity: 1; }
        50%       { opacity: 0.55; }
    }

    .exam-app-title {
        flex: 1;
        text-align: center;
        font-size: 17px;
        font-weight: 600;
        color: #1e293b;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
        padding: 0 4px;
    }

    .exam-app-submit {
        background: #16a34a;
        color: #fff;
        border: none;
        border-radius: 6px;
        padding: 5px 11px;
        font-size: 13px;
        font-weight: 600;
        cursor: pointer;
        white-space: nowrap;
        min-height: 32px;
        display: flex;
        align-items: center;
        gap: 3px;
        flex-shrink: 0;
    }
    .exam-app-submit:active { background: #15803d; }

    /* ===== 5. KHỐI 2: MA TRẬN CÂU HỎI (52px cố định) ===== */
    .exam-matrix-bar {
        flex-shrink: 0;
        height: 52px;
        background: #f8f9fa;
        border-bottom: 1px solid #e2e8f0;
        overflow: hidden;
    }
    .exam-matrix-inner {
        padding: 4px 6px;
        height: 100%;
        box-sizing: border-box;
    }
    .exam-matrix-bar {
        height: auto;
        min-height: 52px;
        max-height: 84px;
    }
    .exam-matrix-grid {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(22px, 1fr));
        grid-auto-rows: 22px;
        gap: 3px;
        height: auto;
    }

    .qnav-cell {
        width: 100%;
        height: 22px;
        min-width: 0;
        border-radius: 4px;
        border: 1px solid #cbd5e1;
        background: #fff;
        font-size: 11px;
        font-weight: 600;
        color: #475569;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        position: relative;
        transition: all 0.1s;
        -webkit-tap-highlight-color: rgba(2, 132, 199, 0.06);
        line-height: 1;
        box-sizing: border-box;
    }
    .qnav-cell:active { transform: scale(0.88); }
    .qnav-cell.current {
        border: 1.5px solid #0284c7;
        background: #e0f2fe;
        color: #0284c7;
    }
    .qnav-cell.answered {
        border-color: #86efac;
        background: #dcfce7;
        color: #15803d;
    }
    /* Dấu sao đỏ câu điểm liệt */
    .qnav-cell.has-critical::after {
        content: '★';
        position: absolute;
        top: -1px;
        left: 1px;
        font-size: 7px;
        color: #dc2626;
        line-height: 1;
        pointer-events: none;
    }

    /* ===== 6. KHỐI 3: BODY (flex 1 — co giãn) ===== */
    .exam-body {
        flex: 1 1 auto;
        display: flex;
        flex-direction: column;
        overflow: hidden;
        min-height: 0;
        background: #fff;
    }

    .exam-left {
        flex: 1 1 auto;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
        overscroll-behavior: contain;
        padding: 0;
        background: #fff;
        min-height: 0;
        touch-action: pan-y;
        padding-bottom: 60px; /* chừa chỗ cho footer nav */
    }

    /* v3.6.3 — 2026-09-15: text + image gọn lại, không chiếm hết màn hình */
    .exam-q-text {
        padding: 8px 12px 6px !important;
        font-size: 16px !important;
        line-height: 1.4 !important;
        font-weight: 600;
        color: #1e293b;
        border-bottom: 1px solid #f1f5f9;
        word-break: break-word;
    }
    .exam-q-text.is-critical { color: #c0392b; font-weight: 700; }

    /* Ảnh câu hỏi — auto height, max 28vh (giảm từ 38vh) */
    .exam-q-img {
        display: block;
        max-width: 100%;
        max-height: 28vh;
        width: auto;
        height: auto;
        object-fit: contain;
        margin: 4px auto;
    }
    .exam-q-img img {
        max-width: 100%;
        max-height: 28vh;
        width: auto;
        height: auto;
        object-fit: contain;
        display: block;
        margin: 0 auto;
    }

    /* v3.6.3 — 2026-09-15: BỎ nested scroll trong .exam-options.
       Chỉ .exam-left cuộn. .exam-options = block bình thường.
       Giảm padding option để 4 đáp án + giải thích fit màn hình. */
    .exam-options {
        padding: 4px 0 12px !important;
        overflow: visible !important;
        max-height: none !important;
        -webkit-overflow-scrolling: auto;
    }
    .exam-opt {
        display: flex;
        align-items: center;
        gap: 10px;
        padding: 9px 12px;
        background: #fff;
        border: none;
        border-bottom: 1px solid #f1f5f9;
        border-radius: 0;
        cursor: pointer;
        width: 100%;
        text-align: left;
        transition: background 0.1s;
        min-height: 46px;
        touch-action: manipulation;
        -webkit-tap-highlight-color: rgba(2, 132, 199, 0.06);
        font-size: 15px;
        line-height: 1.35;
    }
    .exam-opt:last-child { border-bottom: none; }
    .exam-opt:active { background: #dbeafe; }
    .exam-opt.selected { background: #e0f2fe !important; }
    .exam-opt.correct { background: #dcfce7 !important; }
    .exam-opt.wrong   { background: #fee2e2 !important; }
    .exam-opt.focused { border: 1.5px dashed #0284c7; background: #fff; }

    /* Số đáp án trong hình tròn 30px (giảm từ 34px cho mobile) */
    .exam-opt-key {
        width: 30px;
        height: 30px;
        min-width: 30px;
        border-radius: 50% !important;
        border: 1.5px solid #64748b !important;
        background: #fff !important;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 13px;
        font-weight: 700;
        color: #334155;
        flex-shrink: 0;
        transition: all 0.1s;
    }
    .exam-opt.selected .exam-opt-key { background: #0284c7 !important; border-color: #0284c7 !important; color: #fff !important; }
    .exam-opt.correct .exam-opt-key { background: #16a34a !important; border-color: #16a34a !important; color: #fff !important; }
    .exam-opt.wrong   .exam-opt-key { background: #dc2626 !important; border-color: #dc2626 !important; color: #fff !important; }

    .exam-opt-text {
        font-size: 18px;
        line-height: 1.4;
        color: #1e293b;
        flex: 1;
        font-weight: 500;
    }
    .exam-opt.selected .exam-opt-text { color: #0c4a6e; font-weight: 600; }

    /* ===== 7. KHỐI 4: FOOTER NAV (48px cố định đáy) ===== */
    .exam-nav {
        position: relative !important;
        left: 0; right: 0; bottom: 0;
        z-index: 300;
        display: flex !important;
        align-items: center;
        padding: 0;
        background: #fff;
        border-top: 1px solid #e2e8f0;
        box-shadow: 0 -3px 14px rgba(0,0,0,0.09);
        height: 48px;
        padding-bottom: env(safe-area-inset-bottom, 0px);
        flex-shrink: 0;
    }

    .exam-nav-prev,
    .exam-nav-next {
        width: 50px;
        min-width: 50px;
        height: 48px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 22px;
        font-weight: 300;
        background: #fff;
        border: none;
        cursor: pointer;
        color: #0284c7;
        transition: background 0.1s;
        touch-action: manipulation;
        -webkit-tap-highlight-color: rgba(2, 132, 199, 0.08);
        flex-shrink: 0;
        padding: 0;
    }
    .exam-nav-prev:active,
    .exam-nav-next:active { background: #f0f9ff; }
    .exam-nav-prev:disabled { color: #cbd5e1; cursor: default; }

    .exam-nav-center {
        flex: 1;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 0;
        cursor: pointer;
        height: 48px;
        touch-action: manipulation;
        padding: 0 8px;
        transition: background 0.1s;
    }
    .exam-nav-center:active { background: #f0f9ff; }
    .exam-nav-counter {
        font-size: 16px;
        font-weight: 700;
        color: #0284c7;
        line-height: 1.1;
        letter-spacing: 0.3px;
    }
    .exam-nav-label {
        font-size: 9.5px;
        color: #94a3b8;
        font-weight: 500;
        text-transform: uppercase;
        letter-spacing: 0.5px;
    }

    /* Ẩn các nút rườm rà */
    .exam-nav-flag,
    .exam-nav-finish,
    .exam-flag-btn,
    .exam-finish-btn,
    .exam-q-hdr,
    .exam-q-num,
    .exam-critical-badge { display: none !important; }

    /* ===== 8. MODAL KẾT QUẢ — full viewport ===== */
    .result-modal .modal-card {
        width: 100vw;
        max-width: 100vw;
        border-radius: 0;
        min-height: 100dvh;
        max-height: 100dvh;
        display: flex;
        flex-direction: column;
        overflow: hidden;
    }
    .result-modal .modal-body {
        flex: 1;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
    }
    .result-modal .modal-foot {
        padding-bottom: calc(12px + env(safe-area-inset-bottom, 0px));
    }
    .submit-modal .modal-card {
        width: 92vw;
        max-width: 92vw;
        border-radius: 12px;
    }

    /* Ẩn FAB khi đang thi */
    .floating-action-menu { display: none !important; }
}

/* ===== SWIPE GESTURE ===== */


/* ===== A. EXAM HEADER — Fixed top bar app-native ===== */

/* ===== B. ON-LUYEN — Practice screen mobile-first ===== */
@media (max-width: 768px) {
    .ol-practice-screen {
        display: none;
        position: fixed;
        inset: 0;
        background: #fff;
        z-index: 500;
        flex-direction: column;
        overflow: hidden;
    }
    .ol-practice-screen.active { display: flex; }

    /* App-native practice header */
    .ol-prac-header {
        background: #fff;
        color: #1e293b;
        border-bottom: 1.5px solid #e2e8f0;
        padding: 0 12px;
        height: 50px;
        display: flex;
        align-items: center;
        gap: 10px;
        flex-shrink: 0;
        position: relative;
        padding-top: max(env(safe-area-inset-top, 0px), 0px);
    }
    .ol-prac-close {
        background: #f1f5f9;
        border: 1px solid #e2e8f0;
        color: #475569;
        font-size: 15px;
        width: 32px;
        height: 32px;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        flex-shrink: 0;
    }
    .ol-prac-title-bar {
        flex: 1;
        font-size: 14px;
        font-weight: 600;
        color: #1e293b;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    .ol-prac-progress {
        font-size: 13px;
        color: #64748b;
        white-space: nowrap;
        flex-shrink: 0;
    }

    /* Practice body — scrollable */
    .ol-prac-body {
        flex: 1;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
        padding: 0;
        background: #f8fafc;
    }

    /* Question card — full width, no border-radius excess */
    .ol-q-card {
        background: #fff;
        border-radius: 0;
        box-shadow: none;
        margin-bottom: 0;
    }

    .ol-q-header {
        padding: 10px 14px;
        border-bottom: 1px solid #f1f5f9;
        display: flex;
        align-items: center;
        gap: 8px;
        font-size: 13px;
    }
    .ol-q-num {
        font-weight: 700;
        color: #0284c7;
    }
    .ol-q-critical-badge {
        background: #dc2626;
        color: #fff;
        font-size: 10px;
        font-weight: 700;
        padding: 2px 6px;
        border-radius: 3px;
    }
    .ol-q-chapter-tag {
        margin-left: auto;
        font-size: 11px;
        background: #f1f5f9;
        color: #64748b;
        padding: 1px 8px;
        border-radius: 3px;
    }

    .ol-q-content {
        padding: 14px 14px 12px;
        font-size: 16px;
        line-height: 1.5;
        font-weight: 600;
        color: #1e293b;
        border-bottom: 1px solid #f1f5f9;
    }
    .ol-q-content.is-critical { color: #b91c1c; }
    .ol-q-image {
        display: block;
        max-width: 100%;
        max-height: 320px;
        margin: 8px 0;
        border-radius: 0;
    }

    /* Options — app-native row style */
    .ol-options { padding: 4px 12px 12px; }
    .ol-opt {
        border: none;
        border-bottom: 1px solid #e2e8f0;
        border-radius: 0;
        padding: 13px 10px;
        margin-bottom: 0;
        gap: 12px;
        min-height: 52px;
        display: flex;
        align-items: center;
        transition: background 0.12s;
        touch-action: manipulation;
    }
    .ol-opt:last-child { border-bottom: none; }
    .ol-opt:hover { background: #f8fafc; border-color: #e2e8f0; }
    .ol-opt:active { background: #e0f2fe; }
    .ol-opt.selected {
        background: #e0f2fe !important;
        border-color: #0284c7 !important;
    }
    .ol-opt.correct { background: #dcfce7 !important; border-color: #16a34a !important; }
    .ol-opt.wrong { background: #fee2e2 !important; border-color: #dc2626 !important; }

    .ol-opt-num {
        width: 32px;
        height: 32px;
        min-width: 32px;
        border-radius: 50% !important;
        border: 1.5px solid #64748b !important;
        background: #fff !important;
        font-size: 14px;
        font-weight: 700;
        color: #334155;
        display: flex;
        align-items: center;
        justify-content: center;
        flex-shrink: 0;
        transition: all 0.12s;
    }
    .ol-opt.selected .ol-opt-num {
        background: #0284c7 !important;
        border-color: #0284c7 !important;
        color: #fff !important;
    }
    .ol-opt.correct .ol-opt-num {
        background: #16a34a !important;
        border-color: #16a34a !important;
        color: #fff !important;
    }
    .ol-opt.wrong .ol-opt-num {
        background: #dc2626 !important;
        border-color: #dc2626 !important;
        color: #fff !important;
    }

    /* Explanation */
    .ol-explanation {
        margin: 8px 12px 12px;
        border-radius: 6px;
    }

    /* Fixed practice footer */
    .ol-prac-footer {
        position: fixed !important;
        left: 0;
        right: 0;
        bottom: 0;
        z-index: 300;
        display: flex !important;
        align-items: center;
        height: 54px;
        padding: 0;
        background: #fff;
        border-top: 1px solid #e2e8f0;
        box-shadow: 0 -4px 20px rgba(0,0,0,0.1);
        padding-bottom: env(safe-area-inset-bottom, 0px);
        gap: 0;
    }

    .ol-prac-nav-btn {
        width: 54px;
        min-width: 54px;
        height: 54px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 20px;
        font-weight: 300;
        background: #fff;
        border: none;
        border-top: 2px solid transparent;
        cursor: pointer;
        color: #0284c7;
        transition: all 0.12s;
        touch-action: manipulation;
        -webkit-tap-highlight-color: rgba(2,132,199,0.1);
        border-radius: 0;
        padding: 0;
    }
    .ol-prac-nav-btn:active { background: #f0f9ff; }
    .ol-prac-nav-btn:disabled { color: #cbd5e1; cursor: not-allowed; }
    .ol-prac-nav-btn.primary {
        background: #fff;
        color: #0284c7;
        font-size: 13px;
        font-weight: 700;
        width: auto;
        flex: 1;
        padding: 0 16px;
        flex-direction: column;
        gap: 1px;
    }
    .ol-prac-nav-btn.primary:active { background: #f0f9ff; }

    /* Q-dots scroll strip */
    .ol-prac-answers {
        flex: 1;
        height: 54px;
        display: flex;
        align-items: center;
        gap: 3px;
        overflow-x: auto;
        overflow-y: hidden;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        padding: 0 4px;
    }
    .ol-prac-answers::-webkit-scrollbar { display: none; }

    .ol-prac-qdot {
        width: 28px;
        height: 28px;
        min-width: 28px;
        border-radius: 6px;
        border: 1px solid #cbd5e1;
        background: #fff;
        font-size: 11px;
        font-weight: 600;
        color: #475569;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        flex-shrink: 0;
        transition: all 0.1s;
    }
    .ol-prac-qdot:active { transform: scale(0.9); }
    .ol-prac-qdot.current { border-color: #0284c7; background: #e0f2fe; color: #0284c7; }
    .ol-prac-qdot.answered { border-color: #86efac; background: #dcfce7; color: #15803d; }
    .ol-prac-qdot.correct-dot { border-color: #16a34a; background: #16a34a; color: #fff; }
    .ol-prac-qdot.wrong-dot { border-color: #dc2626; background: #dc2626; color: #fff; }
}

/* ===== C. SWIPE GESTURE — applied to both screens ===== */
@media (max-width: 768px) {
    .exam-left,
    .ol-prac-body {
        touch-action: pan-y;
        overflow-x: hidden;
    }

    /* Remove excess margin from options on mobile */
    .exam-opt { margin: 0 !important; }
    .ol-opt { margin: 0 !important; padding-left: 12px !important; padding-right: 12px !important; }
}

/* =========================================================================
   MOBILE + SHARED — desktop exam skin lives ONLY in gtvt-desktop.css
   (removed all min-width:992px exam overrides that fought EcoTek layout)
   ========================================================================= */

/* Ẩn chrome trang khi đang làm bài / xem kết quả */
body.exam-active .bottom-nav,
body.exam-result .bottom-nav,
body.exam-active .mp-top,
body.exam-result .mp-top,
body.exam-active #setupScreen,
body.exam-result #setupScreen,
body.exam-active .floating-action-menu {
    display: none !important;
}
body.exam-active {
    padding-bottom: 0 !important;
    overflow: hidden;
}

.auth-btn-header.is-logged-in,
.desktop-nav a.is-logged-in {
    font-weight: 700;
    letter-spacing: 0;
    text-transform: none;
}
.hv-name-chip {
    display: inline-block;
    max-width: 92px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-size: 13px;
    font-weight: 700;
}

/* Safety: không bao giờ hiện exam + setup cùng lúc */
#examScreen:not(.is-on):not(.exam-visible) {
    display: none !important;
}

.exam-progress-desktop { display: none; }

/* Vuốt chuyển câu */
.exam-left, #examLeft, #pracBody {
    touch-action: pan-y;
    -webkit-overflow-scrolling: touch;
}
.hlx-swiping {
    pointer-events: none;
    will-change: transform, opacity;
}
.exam-opt,
.exam-opt * {
    touch-action: pan-y !important;
}
.hlx-q-spacer {
    height: 28px;
    width: 100%;
    flex-shrink: 0;
    pointer-events: none;
}

/* Ảnh: ẩn khung rỗng; hiện khi JS gắn .has-image */
.gtvt-q-img,
.exam-q-img,
#gtvtImgContainer,
#examQuestionImage,
#examQImgBox {
    display: none;
    margin: 0;
    padding: 0;
    border: none;
    background: transparent;
    min-height: 0;
    height: auto;
    width: auto;
    flex-shrink: 0;
    text-align: center;
}
.gtvt-q-img.has-image,
.exam-q-img.has-image,
#gtvtImgContainer.has-image,
#examQuestionImage.has-image,
#examQImgBox.has-image,
#examQImgBox:has(img[src]:not([src=""])),
.exam-q-img:has(img[src]:not([src=""])) {
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 8px auto 12px;
}


/* ====================================================================
   2026-09-06 FIX: Đáp án có scroll riêng khi câu dài (mobile)
   ==================================================================== */



/* v3.6.3 — 2026-09-15: override đặt ở CUỐI file (xem dưới) để thắng
   rule 20260909-fix set overflow-y:auto trên .exam-options. */

/* 20260909-fix: câu dài không chồng chữ trên mobile */

/* ==========================================================================
   v3.6.3 — 2026-09-15: LAST-WORD OVERRIDE MOBILE SCROLL
   Block 20260909-fix ở trên set overflow-y:auto trên .exam-options →
   gây nested scroll, user không vuốt xem được đáp án dài.
   Block này đặt ở CUỐI file để thắng (cùng specificity + !important, sau hơn).
   ========================================================================== */