/* =============================================================
   NHỊP CẦU THẤU HIỂU – STYLES.CSS
   Tệp này quy định màu sắc, phông chữ, khoảng cách và bố cục.

   MUỐN ĐỔI MÀU: chỉ cần sửa các biến trong khối :root bên dưới.
   Ví dụ: đổi --ngoc: #1f7a78; thành --ngoc: #217f88;
   Toàn bộ nút, đường viền dùng màu đó sẽ đổi theo.

   Mục lục:
   1. Biến màu & phông chữ        6. Góc thấu hiểu (thẻ, bài viết)
   2. Nền tảng chung              7. Học cách đối thoại
   3. Đầu trang & menu            8. Chatbot
   4. Nút bấm & thành phần chung  9. Thử thách 7 ngày
   5. Trang chủ                  10. Giới thiệu, chân trang
                                 11. Màn hình lớn & giảm chuyển động
   ============================================================= */

/* ---------- 1. BIẾN MÀU & PHÔNG CHỮ ---------- */
:root {
  /* Nền giấy hồng đào ấm – lấy từ ánh nắng trong tranh minh họa */
  --giay: #fff7f1;
  --giay-dam: #fcebdd;
  --trang: #ffffff;

  /* Mực tím than cho chữ */
  --muc: #2b2440;
  --muc-nhat: #5e5672;
  --vien: #eadbd0;

  /* Xanh ngọc – tiếng nói của em */
  --ngoc: #1f7a78;
  --ngoc-dam: #155e5c;
  --ngoc-nhat: #dff1ee;

  /* Tím oải hương – tiếng nói của cha mẹ */
  --tim: #8a73c9;
  --tim-dam: #5b47a0;
  --tim-nhat: #ede7f9;

  /* Hồng & đào – điểm nhấn ấm */
  --hong: #e58aa3;
  --hong-dam: #b54a6a;
  --hong-nhat: #fbe4eb;
  --dao: #f6c9a8;
  --dao-nhat: #fdeee2;

  /* Màu phản hồi */
  --tot: #1f7a50;
  --tot-nen: #e1f3e8;
  --vua: #8a5a00;
  --vua-nen: #fdf0d4;
  --chua: #b0413e;
  --chua-nen: #fbe5e2;

  /* Phông chữ */
  --chu-tieu-de: "Fraunces", "Georgia", serif;
  --chu-noi-dung: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;

  /* Kích thước & bo góc */
  --rong-toi-da: 1180px;
  --le: clamp(16px, 4vw, 40px);       /* lề hai bên */
  --bo-lon: 28px;
  --bo-vua: 18px;
  --bo-nho: 12px;
  --bong-do: 0 1px 2px rgba(43, 36, 64, .06), 0 8px 24px -12px rgba(43, 36, 64, .22);
  --cao-menu-duoi: 64px;
}

/* ---------- 2. NỀN TẢNG CHUNG ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 84px; }
body {
  margin: 0;
  background: var(--giay);
  color: var(--muc);
  font-family: var(--chu-noi-dung);
  font-size: 1rem;
  line-height: 1.65;
  overflow-x: hidden;            /* chống tràn ngang trên điện thoại */
  padding-bottom: calc(var(--cao-menu-duoi) + env(safe-area-inset-bottom));
}
img { max-width: 100%; height: auto; display: block; }
h1, h2, h3 { font-family: var(--chu-tieu-de); font-weight: 600; line-height: 1.2; margin: 0 0 .5em; font-variation-settings: "SOFT" 100; letter-spacing: -.01em; }
h1 { font-size: clamp(2.1rem, 7vw, 3.4rem); }
h2 { font-size: clamp(1.45rem, 4.4vw, 2rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
a { color: var(--ngoc-dam); text-underline-offset: 3px; }
button { font: inherit; color: inherit; }
[hidden] { display: none !important; }

:focus-visible { outline: 3px solid var(--tim-dam); outline-offset: 3px; border-radius: 6px; }
/* Tiêu đề nhận tiêu điểm tự động khi chuyển mục: không cần viền */
[tabindex="-1"]:focus { outline: none; }

.bo-qua {
  position: absolute; left: 12px; top: -60px; z-index: 100;
  background: var(--muc); color: #fff; padding: 10px 16px; border-radius: 10px;
}
.bo-qua:focus { top: 12px; }

main { display: block; outline: none; }
.trang { max-width: var(--rong-toi-da); margin: 0 auto; padding: 0 var(--le) 48px; }
.khoi { margin-top: clamp(40px, 8vw, 72px); }
.khoi__dau { max-width: 62ch; margin-bottom: 22px; }
.khoi__dau p { color: var(--muc-nhat); margin: 0; }
.khoi__dau--hang { max-width: none; display: flex; flex-wrap: wrap; gap: 12px 24px; align-items: end; justify-content: space-between; }
.khoi__dau--hang > div { max-width: 62ch; }

/* ---------- 3. ĐẦU TRANG & MENU ---------- */
.dau-trang {
  position: sticky; top: 0; z-index: 30;
  background: rgba(255, 247, 241, .9);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--vien);
}
.dau-trang__trong {
  max-width: var(--rong-toi-da); margin: 0 auto; padding: 10px var(--le);
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.thuong-hieu { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--muc); min-width: 0; }
.thuong-hieu img { width: 40px; height: 40px; flex: none; }
.thuong-hieu__chu { display: flex; flex-direction: column; line-height: 1.15; min-width: 0; }
.thuong-hieu__ten { font-family: var(--chu-tieu-de); font-weight: 600; font-size: 1.12rem; font-variation-settings: "SOFT" 100; }
.thuong-hieu__khau-hieu { font-size: .78rem; color: var(--muc-nhat); }

.menu-ngang { display: none; }

/* Menu dưới cùng – chỉ trên điện thoại */
.menu-duoi {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 40;
  display: grid; grid-template-columns: repeat(6, 1fr);
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-top: 1px solid var(--vien);
  padding-bottom: env(safe-area-inset-bottom);
}
.menu-duoi a {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px;
  min-height: var(--cao-menu-duoi); padding: 6px 2px;
  color: var(--muc-nhat); text-decoration: none; font-size: .68rem; font-weight: 500; line-height: 1.15; text-align: center;
}
.menu-duoi svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.menu-duoi a[aria-current="page"] { color: var(--ngoc-dam); font-weight: 700; }
.menu-duoi a[aria-current="page"] svg { stroke-width: 2.2; }
.menu-duoi a[aria-current="page"]::before {
  content: ""; position: absolute; top: 0; width: 28px; height: 3px; border-radius: 0 0 4px 4px; background: var(--ngoc);
}
.menu-duoi a { position: relative; }

/* ---------- 4. NÚT BẤM & THÀNH PHẦN CHUNG ---------- */
.nut {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 12px 22px; border-radius: 999px;
  font-weight: 600; font-size: .98rem; line-height: 1.2; text-decoration: none; text-align: center;
  border: 2px solid transparent; cursor: pointer;
  transition: background-color .2s, color .2s, border-color .2s, transform .15s;
}
.nut:active { transform: scale(.98); }
.nut--chinh { background: var(--ngoc); color: #fff; }
.nut--vien { background: transparent; color: var(--muc); border-color: var(--muc); }
.nut--canh-bao { background: var(--chua); color: #fff; }
.nut--nho { min-height: 42px; padding: 8px 16px; font-size: .9rem; }
.nhom-nut { display: flex; flex-wrap: wrap; gap: 10px; }

.danh-sach-dau { padding-left: 1.2em; margin: 0; }
.danh-sach-dau li { margin-bottom: .55em; }
.danh-sach-dau li::marker { color: var(--hong-dam); }

/* Đầu mỗi mục (trang con) */
.dau-muc { padding-top: clamp(28px, 6vw, 56px); max-width: 66ch; }
.dau-muc__giai-phap {
  display: inline-block; margin-bottom: 14px; padding: 4px 12px;
  border-radius: 999px; background: var(--tim-nhat); color: var(--tim-dam); font-size: .85rem; font-weight: 600;
}
.dau-muc__mo-ta { font-size: 1.06rem; color: var(--muc-nhat); }
.dau-muc--anh { max-width: none; display: grid; gap: 24px; align-items: center; }
.dau-muc--anh > div { max-width: 60ch; }
.dau-muc--anh img { border-radius: var(--bo-lon); aspect-ratio: 16 / 9; object-fit: cover; width: 100%; }

.thong-bao-nho {
  position: fixed; left: 50%; bottom: calc(var(--cao-menu-duoi) + 16px + env(safe-area-inset-bottom)); z-index: 80;
  transform: translate(-50%, 20px); opacity: 0; pointer-events: none;
  background: var(--muc); color: #fff; padding: 10px 18px; border-radius: 999px; font-size: .9rem;
  transition: opacity .2s, transform .2s; max-width: calc(100vw - 32px);
}
.thong-bao-nho.hien { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 5. TRANG CHỦ ---------- */
.hero { display: grid; gap: 28px; padding-top: clamp(24px, 6vw, 56px); align-items: center; }
.hero__du-an { font-size: .88rem; color: var(--muc-nhat); margin-bottom: 10px; }
.hero__ten {
  font-size: clamp(3rem, 15vw, 6rem); line-height: .95; letter-spacing: -.03em; margin-bottom: 14px;
  font-weight: 650; font-variation-settings: "SOFT" 100, "opsz" 144;
}
.hero__khau-hieu {
  font-family: var(--chu-tieu-de); font-style: italic; font-size: clamp(1.25rem, 4.6vw, 1.7rem);
  color: var(--ngoc-dam); margin-bottom: 16px; font-variation-settings: "SOFT" 100;
}
.hero__gioi-thieu { font-size: 1.05rem; color: var(--muc-nhat); max-width: 52ch; margin-bottom: 24px; }
.hero .nhom-nut .nut { flex: 1 1 auto; }

.hero__anh { margin: 0; position: relative; padding-top: 58px; }
.hero__anh img { border-radius: var(--bo-lon); aspect-ratio: 16 / 10; object-fit: cover; width: 100%; box-shadow: var(--bong-do); }

/* Đường “nhịp cầu” nối hai bong bóng phía trên ảnh */
.cau-noi { position: absolute; top: 0; left: 0; right: 0; height: 84px; pointer-events: none; }
.cau-noi__cung { position: absolute; left: 12%; right: 12%; top: 8px; width: 76%; height: 62px; overflow: visible; }
.cau-noi__cung path {
  fill: none; stroke: var(--muc); stroke-width: 2.4; stroke-linecap: round; vector-effect: non-scaling-stroke;
  stroke-dasharray: 400; stroke-dashoffset: 400; animation: ve-cau 1.6s .3s cubic-bezier(.6, 0, .2, 1) forwards;
}
.cau-noi__tim { position: absolute; left: 50%; top: 0; width: 26px; height: 24px; transform: translate(-50%, -2px) scale(0); fill: var(--hong); animation: hien-tim .5s 1.7s cubic-bezier(.3, 1.6, .5, 1) forwards; }
.bong {
  position: absolute; top: 46px; padding: 8px 16px; font-weight: 700; font-size: .95rem; color: #fff;
  box-shadow: var(--bong-do); z-index: 2;
}
.bong--em { left: 4%; background: var(--ngoc); border-radius: 20px 20px 20px 6px; }
.bong--cha-me { right: 4%; background: var(--tim-dam); border-radius: 20px 20px 6px 20px; }
@keyframes ve-cau { to { stroke-dashoffset: 0; } }
@keyframes hien-tim { to { transform: translate(-50%, -2px) scale(1); } }

.de-tai {
  margin-top: clamp(36px, 7vw, 64px); padding: 22px clamp(18px, 4vw, 32px);
  border-radius: var(--bo-lon); background: var(--trang); border: 1px solid var(--vien);
  display: grid; gap: 6px;
}
.de-tai__nhan { margin: 0; font-size: .85rem; font-weight: 700; color: var(--hong-dam); }
.de-tai__ten { margin: 0; font-family: var(--chu-tieu-de); font-size: clamp(1.05rem, 3.4vw, 1.35rem); line-height: 1.45; font-variation-settings: "SOFT" 100; }

.luoi-hoat-dong { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.hoat-dong {
  position: relative; padding: 22px; border-radius: var(--bo-vua);
  display: flex; flex-direction: column; gap: 4px;
}
.hoat-dong h3 { margin: 4px 0 4px; font-size: 1.2rem; }
.hoat-dong p { margin: 0 0 14px; color: var(--muc-nhat); }
.hoat-dong__so { font-size: .82rem; font-weight: 700; }
.hoat-dong--ngoc { background: var(--ngoc-nhat); } .hoat-dong--ngoc .hoat-dong__so { color: var(--ngoc-dam); }
.hoat-dong--tim  { background: var(--tim-nhat); }  .hoat-dong--tim .hoat-dong__so { color: var(--tim-dam); }
.hoat-dong--hong { background: var(--hong-nhat); } .hoat-dong--hong .hoat-dong__so { color: var(--hong-dam); }
.hoat-dong--dao  { background: var(--dao-nhat); }  .hoat-dong--dao .hoat-dong__so { color: #8a4b1e; }
.lien-ket-the { margin-top: auto; font-weight: 600; color: var(--muc); }
/* Cả thẻ bấm được: mở rộng vùng chạm của liên kết */
.lien-ket-the::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }

.thong-diep {
  margin-top: clamp(48px, 9vw, 88px); display: grid; overflow: hidden;
  border-radius: var(--bo-lon); background: var(--muc); color: #fff;
}
.thong-diep__anh { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.thong-diep__chu { padding: clamp(24px, 5vw, 48px); }
.thong-diep__cau { font-family: var(--chu-tieu-de); font-size: clamp(1.35rem, 4.6vw, 2rem); line-height: 1.35; margin-bottom: 10px; font-variation-settings: "SOFT" 100; }
.thong-diep__nguon { color: #cfc6e6; font-size: .9rem; margin-bottom: 22px; }
.thong-diep .nut--chinh { background: var(--dao); color: var(--muc); }
.thong-diep--ket { background: var(--ngoc-dam); }

/* ---------- 6. GÓC THẤU HIỂU ---------- */
/* Bộ lọc chủ đề */
.bo-loc { display: flex; gap: 8px; overflow-x: auto; padding: 2px 2px 10px; margin: 0 -2px 8px; scrollbar-width: thin; }
.bo-loc button {
  flex: none; min-height: 40px; padding: 6px 14px; border-radius: 999px;
  border: 1.5px solid var(--vien); background: var(--trang); cursor: pointer; font-size: .9rem; font-weight: 500;
}
.bo-loc button[aria-pressed="true"] { background: var(--muc); border-color: var(--muc); color: #fff; }

/* Lưới 12 thẻ */
.luoi-tinh-huong { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.the-th {
  width: 100%; height: 100%; text-align: left; cursor: pointer;
  display: flex; flex-direction: column; gap: 10px;
  padding: 20px; border-radius: var(--bo-vua); background: var(--trang);
  border: 1px solid var(--vien); box-shadow: var(--bong-do);
  transition: transform .2s, box-shadow .2s, border-color .2s;
}
.the-th__dau { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.the-th__so { font-family: var(--chu-tieu-de); font-size: 1.6rem; font-weight: 600; color: var(--hong); line-height: 1; }
.the-th__chu-de { font-size: .78rem; font-weight: 600; color: var(--tim-dam); background: var(--tim-nhat); padding: 3px 10px; border-radius: 999px; }
.the-th__ten { font-family: var(--chu-tieu-de); font-size: 1.22rem; font-weight: 600; line-height: 1.25; font-variation-settings: "SOFT" 100; }
.the-th__boi-canh { color: var(--muc-nhat); font-size: .94rem; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.the-th__hai-ben { display: flex; gap: 6px; margin-top: auto; }
.the-th__hai-ben span { font-size: .78rem; font-weight: 600; padding: 4px 10px; }
.the-th__hai-ben .em { background: var(--ngoc-nhat); color: var(--ngoc-dam); border-radius: 12px 12px 12px 3px; }
.the-th__hai-ben .cm { background: var(--tim-nhat); color: var(--tim-dam); border-radius: 12px 12px 3px 12px; }
.the-th__mo { font-weight: 600; color: var(--ngoc-dam); font-size: .92rem; }
.the-th.da-lam .the-th__mo::before { content: "✓ "; color: var(--tot); }

/* Hộp thẻ tình huống (dialog) */
.hop-the {
  width: min(760px, 100%); max-width: 100%; max-height: 100%; margin: auto 0 0;
  padding: 0; border: 0; border-radius: var(--bo-lon) var(--bo-lon) 0 0;
  background: var(--giay); color: var(--muc); box-shadow: 0 -10px 40px rgba(43, 36, 64, .3);
  position: fixed; inset: auto 0 0 0;
}
.hop-the::backdrop { background: rgba(43, 36, 64, .55); }
.hop-the[open] { animation: truot-len .28s ease-out; }
@keyframes truot-len { from { transform: translateY(40px); opacity: 0; } }
.hop-the__trong { padding: 20px 18px calc(28px + env(safe-area-inset-bottom)); max-height: 92vh; max-height: 92dvh; overflow-y: auto; overscroll-behavior: contain; }
.hop-the__thanh { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 10px; position: sticky; top: -20px; background: var(--giay); padding: 10px 0; z-index: 2; }
.hop-the__dong {
  width: 44px; height: 44px; flex: none; border-radius: 50%; border: 1.5px solid var(--vien); background: var(--trang); cursor: pointer;
  display: grid; place-items: center; font-size: 1.4rem; line-height: 1;
}
.hop-the h2 { margin-bottom: 8px; }
.hop-the__boi-canh { background: var(--trang); border-radius: var(--bo-vua); padding: 16px 18px; border: 1px solid var(--vien); }
.hop-the__nhan { font-size: .85rem; font-weight: 700; color: var(--hong-dam); margin-bottom: 4px; }

/* Hai bong bóng suy nghĩ đối diện nhau, nối bằng nhịp cầu */
.hai-phia { display: grid; gap: 14px; margin: 22px 0; position: relative; }
.suy-nghi { padding: 16px 18px; position: relative; }
.suy-nghi h3 { font-size: 1rem; font-family: var(--chu-noi-dung); font-weight: 700; margin-bottom: 6px; }
.suy-nghi p { margin: 0; }
.suy-nghi--em { background: var(--ngoc-nhat); border-radius: 22px 22px 22px 6px; margin-right: 12%; }
.suy-nghi--em h3 { color: var(--ngoc-dam); }
.suy-nghi--cm { background: var(--tim-nhat); border-radius: 22px 22px 6px 22px; margin-left: 12%; }
.suy-nghi--cm h3 { color: var(--tim-dam); }

.chon-ung-xu h3, .mo-loi h3, .thuc-hanh h3 { font-size: 1.15rem; }
.phuong-an { list-style: none; margin: 0 0 8px; padding: 0; display: grid; gap: 10px; }
.phuong-an button {
  width: 100%; text-align: left; cursor: pointer; padding: 14px 16px; min-height: 52px;
  border-radius: var(--bo-nho); border: 1.5px solid var(--vien); background: var(--trang);
  display: flex; gap: 12px; align-items: flex-start; line-height: 1.45;
  transition: border-color .2s, background-color .2s;
}
.phuong-an__ky { flex: none; width: 28px; height: 28px; border-radius: 50%; background: var(--giay-dam); display: grid; place-items: center; font-weight: 700; font-size: .85rem; }
.phuong-an button[aria-pressed="true"] { border-color: var(--muc); border-width: 2px; }
.phuong-an button.muc-phu-hop[aria-pressed="true"] .phuong-an__ky { background: var(--tot); color: #fff; }
.phuong-an button.muc-can-nhac[aria-pressed="true"] .phuong-an__ky { background: var(--vua); color: #fff; }
.phuong-an button.muc-chua-phu-hop[aria-pressed="true"] .phuong-an__ky { background: var(--chua); color: #fff; }

.phan-hoi { border-radius: var(--bo-nho); padding: 14px 16px; margin: 6px 0 4px; animation: hien-ra .25s ease-out; }
.phan-hoi strong { display: block; margin-bottom: 2px; }
.phan-hoi p { margin: 0; }
.phan-hoi--phu-hop, .phan-hoi--dung { background: var(--tot-nen); color: #154b33; }
.phan-hoi--can-nhac { background: var(--vua-nen); color: #5c3c00; }
.phan-hoi--chua-phu-hop, .phan-hoi--sai { background: var(--chua-nen); color: #7a2724; }
@keyframes hien-ra { from { opacity: 0; transform: translateY(-4px); } }

.mo-loi { margin-top: 24px; }
.mo-loi__cau {
  position: relative; background: var(--trang); border: 2px solid var(--ngoc); border-radius: 22px 22px 22px 6px;
  padding: 16px 18px; font-family: var(--chu-tieu-de); font-size: 1.12rem; line-height: 1.5; font-variation-settings: "SOFT" 100; margin-bottom: 10px;
}
.mo-loi[data-khoa="true"] .mo-loi__cau { filter: blur(5px); user-select: none; }
.mo-loi__khoa { font-size: .9rem; color: var(--muc-nhat); }

.thuc-hanh { margin-top: 28px; padding-top: 22px; border-top: 1px dashed var(--vien); }
.thuc-hanh label { font-weight: 600; display: block; margin-bottom: 6px; }
textarea {
  width: 100%; min-height: 96px; padding: 12px 14px; border-radius: var(--bo-nho);
  border: 1.5px solid var(--vien); background: var(--trang); font: inherit; color: var(--muc); resize: vertical;
}
textarea:focus-visible { outline: 3px solid var(--tim-dam); outline-offset: 1px; border-color: transparent; }
.tu-kiem { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 8px; }
.tu-kiem label { display: flex; gap: 10px; align-items: flex-start; font-weight: 400; cursor: pointer; padding: 8px 0; }
.tu-kiem input { width: 22px; height: 22px; accent-color: var(--ngoc); flex: none; margin-top: 2px; }
.thuc-hanh__ket { margin-top: 10px; font-weight: 600; color: var(--ngoc-dam); min-height: 1.6em; }
.ghi-chu-nho { font-size: .85rem; color: var(--muc-nhat); }

/* Thư viện bài viết */
.luoi-bai { display: grid; gap: 18px; }
.the-bai { display: flex; flex-direction: column; background: var(--trang); border-radius: var(--bo-vua); overflow: hidden; border: 1px solid var(--vien); position: relative; transition: transform .2s, box-shadow .2s; }
.the-bai__anh { aspect-ratio: 16 / 9; overflow: hidden; background: var(--giay-dam); }
.the-bai__anh img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s; }
.the-bai__chu { padding: 18px 20px 20px; display: flex; flex-direction: column; flex: 1; }
.the-bai__meta { font-size: .8rem; font-weight: 600; color: var(--hong-dam); margin-bottom: 6px; }
.the-bai h3 { font-size: 1.2rem; margin-bottom: 8px; }
.the-bai p { color: var(--muc-nhat); font-size: .94rem; }
.the-bai .lien-ket-the { color: var(--ngoc-dam); }

/* Giao diện đọc bài */
.trang--doc { max-width: 820px; }
.bai-doc { padding-top: 20px; }
.bai-doc__quay-lai { display: inline-flex; align-items: center; gap: 6px; min-height: 44px; font-weight: 600; text-decoration: none; color: var(--muc); }
.bai-doc__quay-lai svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 2; }
.bai-doc__meta { font-size: .9rem; font-weight: 600; color: var(--hong-dam); margin: 18px 0 8px; }
.bai-doc h1 { font-size: clamp(1.9rem, 6.4vw, 3rem); line-height: 1.12; margin-bottom: 18px; }
.bai-doc__thoi-gian { color: var(--muc-nhat); font-size: .9rem; }
.bai-doc figure { margin: 26px 0; }
.bai-doc figure img { border-radius: var(--bo-vua); width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.bai-doc figcaption { font-size: .85rem; color: var(--muc-nhat); margin-top: 8px; }
.bai-doc__than p { font-size: 1.08rem; line-height: 1.8; max-width: 68ch; }
.bai-doc__than p:first-of-type::first-letter {
  font-family: var(--chu-tieu-de); float: left; font-size: 3.4em; line-height: .9; padding: 6px 10px 0 0; color: var(--ngoc-dam); font-weight: 600;
}
.bai-doc__dieu-huong { display: flex; flex-wrap: wrap; gap: 10px; margin: 30px 0 10px; padding-top: 22px; border-top: 1px solid var(--vien); }
.bai-lien-quan { margin-top: 36px; }
.bai-lien-quan .luoi-bai { grid-template-columns: 1fr; }

/* ---------- 7. HỌC CÁCH ĐỐI THOẠI ---------- */
.the-ky-nang { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; margin-bottom: 22px; }
.the-ky-nang button {
  text-align: left; cursor: pointer; min-height: 64px; padding: 12px 14px;
  border-radius: var(--bo-nho); border: 1.5px solid var(--vien); background: var(--trang);
  display: flex; flex-direction: column; gap: 2px; line-height: 1.3;
}
.the-ky-nang__so { font-size: .78rem; font-weight: 700; color: var(--hong-dam); }
.the-ky-nang__ten { font-weight: 600; font-size: .95rem; }
.the-ky-nang button[aria-selected="true"] { background: var(--muc); color: #fff; border-color: var(--muc); }
.the-ky-nang button[aria-selected="true"] .the-ky-nang__so { color: var(--dao); }

.ky-nang { display: grid; gap: 22px; }
.ky-nang__hoc, .ky-nang__luyen { border-radius: var(--bo-lon); padding: clamp(20px, 4vw, 32px); }
.ky-nang__hoc { background: var(--trang); border: 1px solid var(--vien); }
.ky-nang__luyen { background: var(--ngoc-nhat); }
.nhan-phan { display: inline-block; font-size: .82rem; font-weight: 700; padding: 3px 12px; border-radius: 999px; margin-bottom: 12px; }
.nhan-phan--hoc { background: var(--tim-nhat); color: var(--tim-dam); }
.nhan-phan--luyen { background: var(--ngoc); color: #fff; }
.ky-nang__tom-tat { font-family: var(--chu-tieu-de); font-size: 1.25rem; font-style: italic; color: var(--ngoc-dam); font-variation-settings: "SOFT" 100; }
.meo { list-style: none; padding: 0; margin: 14px 0 0; display: grid; gap: 8px; }
.meo li { padding: 10px 14px 10px 40px; background: var(--giay); border-radius: var(--bo-nho); position: relative; }
.meo li::before { content: ""; position: absolute; left: 14px; top: 17px; width: 12px; height: 12px; border-radius: 50%; background: var(--hong); }

/* So sánh câu nói: thẻ lật */
.so-sanh { margin-top: 22px; }
.so-sanh__vi-du { font-weight: 500; margin-bottom: 12px; }
.the-lat { perspective: 1200px; }
.the-lat__trong { display: grid; transition: transform .6s cubic-bezier(.4, .2, .2, 1); transform-style: preserve-3d; }
.the-lat__mat {
  grid-area: 1 / 1; backface-visibility: hidden; -webkit-backface-visibility: hidden;
  padding: 18px; border-radius: var(--bo-vua); min-height: 140px; display: flex; flex-direction: column; gap: 6px;
}
.the-lat__mat--truoc { background: var(--chua-nen); }
.the-lat__mat--sau { background: var(--tot-nen); transform: rotateY(180deg); }
.the-lat.da-lat .the-lat__trong { transform: rotateY(180deg); }
.the-lat__nhan { font-size: .85rem; font-weight: 700; }
.the-lat__mat--truoc .the-lat__nhan { color: var(--chua); }
.the-lat__mat--sau .the-lat__nhan { color: var(--tot); }
.the-lat__cau { font-family: var(--chu-tieu-de); font-size: 1.15rem; line-height: 1.45; margin: 0; font-variation-settings: "SOFT" 100; }
.the-lat__vi-sao { font-size: .92rem; margin: 6px 0 0; color: #1d4d36; }
.the-lat__nut { margin-top: 12px; }

.bai-tap { margin-top: 18px; padding: 18px; border-radius: var(--bo-vua); background: var(--trang); }
.bai-tap + .bai-tap { margin-top: 14px; }
.bai-tap__cau { font-weight: 600; margin-bottom: 12px; }
.bai-tap__so { color: var(--ngoc-dam); }
.ky-nang__ket { margin-top: 16px; font-weight: 600; }

/* Mini game */
.tro-choi__khung { background: var(--muc); color: #fff; border-radius: var(--bo-lon); padding: clamp(20px, 5vw, 40px); }
.tro-choi__tien-do { display: flex; justify-content: space-between; gap: 12px; font-size: .9rem; color: #cfc6e6; margin-bottom: 14px; }
.tro-choi__boi-canh { font-family: var(--chu-tieu-de); font-size: clamp(1.2rem, 4vw, 1.5rem); margin-bottom: 18px; font-variation-settings: "SOFT" 100; }
.tro-choi__lua-chon { display: grid; gap: 12px; }
.tro-choi__lua-chon button {
  text-align: left; cursor: pointer; padding: 16px 18px; min-height: 56px; border-radius: 22px 22px 22px 6px;
  border: 2px solid rgba(255, 255, 255, .25); background: rgba(255, 255, 255, .08); color: #fff; line-height: 1.45;
  display: flex; gap: 12px; align-items: flex-start;
}
.tro-choi__lua-chon button:nth-child(2) { border-radius: 22px 22px 6px 22px; }
.tro-choi__lua-chon button b { flex: none; width: 28px; height: 28px; border-radius: 50%; background: rgba(255, 255, 255, .16); display: grid; place-items: center; font-size: .85rem; }
.tro-choi__lua-chon button.dung { border-color: #7fd6a8; background: rgba(127, 214, 168, .18); }
.tro-choi__lua-chon button.sai { border-color: #f2a0a0; background: rgba(242, 160, 160, .14); }
.tro-choi__lua-chon button:disabled { cursor: default; }
.tro-choi__loi-giai { margin-top: 16px; padding: 14px 16px; border-radius: var(--bo-nho); background: rgba(255, 255, 255, .1); }
.tro-choi__loi-giai p { margin: 0 0 12px; }
.tro-choi .nut--chinh { background: var(--dao); color: var(--muc); }
.tro-choi .nut--vien { color: #fff; border-color: #fff; }
.tro-choi__ket-qua { text-align: center; }
.tro-choi__diem { font-family: var(--chu-tieu-de); font-size: clamp(3rem, 12vw, 4.5rem); line-height: 1; margin: 6px 0 10px; }
.tro-choi__ket-qua .nhom-nut { justify-content: center; }

/* ---------- 8. CHATBOT ---------- */
.chuc-nang-ai { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.chuc-nang-ai li { padding: 18px 20px; border-radius: var(--bo-vua); background: var(--trang); border: 1px solid var(--vien); }
.chuc-nang-ai li:nth-child(odd) { border-radius: 22px 22px 22px 6px; }
.chuc-nang-ai li:nth-child(even) { border-radius: 22px 22px 6px 22px; }
.chuc-nang-ai h3 { font-size: 1.08rem; margin-bottom: 4px; }
.chuc-nang-ai p { margin: 0; color: var(--muc-nhat); font-size: .94rem; }

/* Nut truy cap chatbot: tranh nhung iframe co the bi chan */
.chatbot-cta { display: flex; align-items: center; gap: clamp(16px, 4vw, 32px); padding: clamp(22px, 5vw, 44px); border-radius: var(--bo-lon); background: linear-gradient(130deg, #e3f7f3 0%, #f4ecfc 72%, #fff8e8 100%); border: 1px solid #dfebe8; box-shadow: var(--bong-do); }
.chatbot-cta__icon { display: grid; place-items: center; flex: 0 0 94px; width: 94px; height: 94px; background: #fff; border: 2px solid #bce8df; border-radius: 28px; font-size: 3rem; }
.chatbot-cta__body { min-width: 0; }
.chatbot-cta__body h2 { margin: 0 0 10px; color: #145b5e; font-size: clamp(1.3rem, 3vw, 2rem); }
.chatbot-cta__body p { max-width: 65ch; line-height: 1.7; margin: 0 0 20px; }
.chatbot-cta__link { display: inline-flex; text-align: center; align-items: center; justify-content: center; gap: 8px; min-height: 52px; font-weight: 750; }
@media (max-width: 599px) { .chatbot-cta { flex-direction: column; text-align: center; } .chatbot-cta__icon { flex-basis: 76px; width: 76px; height: 76px; border-radius: 22px; font-size: 2.5rem; } .chatbot-cta__link { width: 100%; } }

.khoi--hai-cot { display: grid; gap: 22px; }
.goi-y-cau, .an-toan { padding: clamp(20px, 4vw, 30px); border-radius: var(--bo-lon); }
.goi-y-cau { background: var(--tim-nhat); }
.goi-y-cau > p { color: var(--muc-nhat); }
.goi-y-cau ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.goi-y-cau li { display: flex; gap: 10px; align-items: flex-start; justify-content: space-between; background: var(--trang); padding: 12px 12px 12px 16px; border-radius: 18px 18px 18px 6px; }
.goi-y-cau li span { font-size: .95rem; }
.nut-chep { flex: none; min-height: 40px; min-width: 56px; padding: 6px 12px; border-radius: 999px; border: 1.5px solid var(--tim-dam); background: transparent; color: var(--tim-dam); font-weight: 600; font-size: .85rem; cursor: pointer; }
.an-toan { background: var(--hong-nhat); }

/* ---------- 9. THỬ THÁCH 7 NGÀY ---------- */
.tien-do { background: var(--trang); border: 1px solid var(--vien); border-radius: var(--bo-lon); padding: clamp(18px, 4vw, 28px); box-shadow: var(--bong-do); }
.tien-do__chu { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline; gap: 4px 16px; margin-bottom: 12px; }
.tien-do__nhan { margin: 0; font-family: var(--chu-tieu-de); font-size: 1.25rem; font-weight: 600; font-variation-settings: "SOFT" 100; }
.tien-do__so { margin: 0; font-weight: 600; color: var(--ngoc-dam); }
.tien-do__thanh { position: relative; height: 14px; border-radius: 999px; background: var(--giay-dam); }
.tien-do__day { position: absolute; left: 0; top: 0; bottom: 0; width: 0; border-radius: inherit; background: linear-gradient(90deg, var(--ngoc), var(--tim)); transition: width .5s cubic-bezier(.4, 0, .2, 1); }
.tien-do__moc { position: absolute; inset: 0; list-style: none; margin: 0; padding: 0 2px; display: flex; justify-content: space-between; align-items: center; }
.tien-do__moc li { width: 10px; height: 10px; border-radius: 50%; background: var(--trang); border: 2px solid var(--vien); }
.tien-do__moc li.xong { border-color: #fff; background: #fff; }
.tien-do__loi { margin: 10px 0 0; font-size: .92rem; color: var(--muc-nhat); }

.hanh-trinh { list-style: none; margin: 26px 0 0; padding: 0; position: relative; display: grid; gap: 14px; }
.hanh-trinh::before { content: ""; position: absolute; left: 25px; top: 20px; bottom: 20px; width: 2px; background: repeating-linear-gradient(var(--vien) 0 6px, transparent 6px 12px); }
.ngay { position: relative; display: grid; grid-template-columns: 52px 1fr; gap: 12px; align-items: start; }
.ngay__so {
  width: 52px; height: 52px; border-radius: 50%; display: grid; place-items: center; position: relative; z-index: 1;
  background: var(--trang); border: 2px solid var(--vien); font-family: var(--chu-tieu-de); font-weight: 600; font-size: 1.2rem; line-height: 1;
  text-align: center;
}
.ngay__so small { display: block; font-family: var(--chu-noi-dung); font-size: .6rem; font-weight: 600; color: var(--muc-nhat); }
.ngay.xong .ngay__so { background: var(--ngoc); border-color: var(--ngoc); color: #fff; }
.ngay.xong .ngay__so small { color: #d6efec; }
.ngay__the { background: var(--trang); border: 1px solid var(--vien); border-radius: var(--bo-vua); padding: 16px 18px; transition: border-color .2s, background-color .2s; }
.ngay.xong .ngay__the { border-color: var(--ngoc); background: #f6fcfb; }
.ngay__the h3 { font-size: 1.12rem; margin-bottom: 4px; }
.ngay__the p { margin-bottom: 8px; color: var(--muc-nhat); font-size: .95rem; }
.ngay__goi-y { font-family: var(--chu-tieu-de); font-style: italic; color: var(--tim-dam) !important; font-size: 1rem !important; font-variation-settings: "SOFT" 100; }
.ngay__danh-dau { display: flex; align-items: center; gap: 10px; min-height: 44px; font-weight: 600; cursor: pointer; margin-top: 4px; }
.ngay__danh-dau input { width: 24px; height: 24px; accent-color: var(--ngoc); flex: none; }
.ngay details { margin-top: 6px; }
.ngay summary { cursor: pointer; min-height: 40px; display: flex; align-items: center; color: var(--ngoc-dam); font-weight: 600; font-size: .92rem; }
.ngay textarea { min-height: 80px; margin-top: 6px; }
.ngay__luu { font-size: .8rem; color: var(--muc-nhat); margin: 4px 0 0 !important; min-height: 1.3em; }

.thu-thach__cuoi { display: grid; gap: 20px; margin-top: 34px; }
.rieng-tu { background: var(--tim-nhat); border-radius: var(--bo-lon); padding: clamp(20px, 4vw, 28px); }
.rieng-tu h2 { font-size: 1.3rem; }
.rieng-tu p { color: var(--muc); }
.xoa-tien-do__xac-nhan { margin-top: 12px; padding: 14px 16px; background: var(--chua-nen); border-radius: var(--bo-nho); }
.xoa-tien-do__xac-nhan p { margin-bottom: 10px; font-weight: 600; }
.xoa-tien-do__bao { margin-top: 10px; color: var(--ngoc-dam); font-weight: 600; min-height: 1.6em; }

/* ---------- 10. GIỚI THIỆU, CHÂN TRANG ---------- */
.gioi-thieu { display: grid; gap: 24px; }
.gioi-thieu__ten-de-tai { font-family: var(--chu-tieu-de); font-size: clamp(1.15rem, 3.6vw, 1.5rem); line-height: 1.45; font-variation-settings: "SOFT" 100; }
.gioi-thieu__anh { margin: 0; }
.gioi-thieu__anh img { border-radius: var(--bo-lon); width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.gioi-thieu__anh figcaption, .ghi-chu-anh { font-size: .82rem; color: var(--muc-nhat); margin-top: 8px; }
.gioi-thieu__doan { max-width: 70ch; }
.gioi-thieu__doan h2 { margin-top: 10px; }

.bon-giai-phap { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.bon-giai-phap li { padding: 20px; background: var(--trang); border: 1px solid var(--vien); border-left: 6px solid var(--ngoc); border-radius: var(--bo-vua); }
.bon-giai-phap li:nth-child(2) { border-left-color: var(--tim); }
.bon-giai-phap li:nth-child(3) { border-left-color: var(--hong); }
.bon-giai-phap li:nth-child(4) { border-left-color: var(--dao); }
.bon-giai-phap h3 { font-size: 1.1rem; }
.bon-giai-phap p { color: var(--muc-nhat); margin-bottom: 6px; }
.bon-giai-phap a { font-weight: 600; display: inline-block; min-height: 32px; }

.cac-buoc { margin: 0; padding: 0; list-style: none; counter-reset: buoc; display: grid; gap: 12px; }
.cac-buoc li { counter-increment: buoc; position: relative; padding: 2px 0 0 48px; min-height: 36px; }
.cac-buoc li::before {
  content: counter(buoc); position: absolute; left: 0; top: 0; width: 34px; height: 34px; border-radius: 50%;
  background: var(--ngoc); color: #fff; display: grid; place-items: center; font-weight: 700; font-size: .9rem;
}

.chan-trang { margin-top: 24px; background: #104c50; border-top: 4px solid #f0c641; }
.chan-trang__trong { max-width: var(--rong-toi-da); margin: 0 auto; padding: 28px var(--le) 32px; text-align: center; }
.chan-trang__ban-quyen { color: #ffe44d; font-family: var(--chu-tieu-de); font-size: clamp(1.3rem, 3.2vw, 2.35rem); font-weight: 900; line-height: 1.4; letter-spacing: .025em; text-transform: uppercase; margin: 0; overflow-wrap: anywhere; text-shadow: 0 1px 0 #073337; }
.chan-trang__ban-quyen a { color: inherit; font: inherit; text-decoration: none; white-space: nowrap; }
.chan-trang__ban-quyen a:focus-visible, .chan-trang__ban-quyen a:hover { text-decoration: underline; }


/* ---------- 11. MÀN HÌNH LỚN HƠN ---------- */
@media (min-width: 600px) {
  .luoi-hoat-dong, .luoi-tinh-huong, .luoi-bai, .chuc-nang-ai, .bon-giai-phap { grid-template-columns: repeat(2, 1fr); }
  .the-ky-nang { grid-template-columns: repeat(4, 1fr); }
  .hero .nhom-nut .nut { flex: 0 0 auto; }
  .bai-lien-quan .luoi-bai { grid-template-columns: repeat(2, 1fr); }
  .hop-the { margin: auto; inset: 0; border-radius: var(--bo-lon); max-height: 90vh; }
  .hop-the__trong { padding: 24px 30px 32px; max-height: 90vh; }
  .hai-phia { grid-template-columns: 1fr 1fr; gap: 18px; }
  .suy-nghi--em, .suy-nghi--cm { margin: 0; }
  .hai-phia::after { content: ""; position: absolute; left: 50%; top: -14px; width: 40%; height: 26px; transform: translateX(-50%); border: 2px solid var(--muc); border-bottom: 0; border-radius: 50% 50% 0 0 / 100% 100% 0 0; opacity: .5; }
}

@media (min-width: 900px) {
  body { padding-bottom: 0; }
  .menu-duoi { display: none; }
  .thong-bao-nho { bottom: 24px; }
  .menu-ngang { display: flex; gap: 2px; }
  .menu-ngang a {
    padding: 8px 12px; border-radius: 999px; text-decoration: none; color: var(--muc); font-weight: 500; font-size: .92rem; white-space: nowrap;
  }
  .menu-ngang a[aria-current="page"] { background: var(--muc); color: #fff; }
  .hero { grid-template-columns: 1fr 1fr; gap: 48px; }
  .hero .nhom-nut .nut { padding: 12px 18px; }
  .luoi-hoat-dong { grid-template-columns: repeat(4, 1fr); }
  .luoi-tinh-huong, .luoi-bai { grid-template-columns: repeat(3, 1fr); }
  .thong-diep { grid-template-columns: 1fr 1.2fr; align-items: center; }
  .thong-diep__anh { height: 100%; aspect-ratio: auto; }
  .thong-diep--ket { grid-template-columns: 1fr; }
  .thong-diep--ket .thong-diep__chu { max-width: 860px; }
  .dau-muc--anh { grid-template-columns: 1.2fr 1fr; gap: 40px; }
  .chuc-nang-ai { grid-template-columns: repeat(4, 1fr); }
  .khoi--hai-cot { grid-template-columns: 1fr 1fr; align-items: start; }
  .ky-nang { grid-template-columns: 1.1fr 1fr; align-items: start; }
  .gioi-thieu { grid-template-columns: 1.2fr 1fr; align-items: start; }
  .gioi-thieu__doan { grid-column: 1 / -1; }
  .thu-thach__cuoi { grid-template-columns: 1.4fr 1fr; align-items: start; }
  .tien-do { position: sticky; top: 76px; z-index: 5; }
  .bai-lien-quan .luoi-bai { grid-template-columns: repeat(2, 1fr); }

}

@media (min-width: 1100px) {
  .menu-ngang a { padding: 8px 14px; font-size: .95rem; }
}

/* Màn hình rất hẹp (dưới 380px) */
@media (max-width: 379px) {
  .thuong-hieu__khau-hieu { display: none; }
  .menu-duoi a { font-size: .62rem; }
  .bong { font-size: .85rem; padding: 6px 12px; }
}

/* Hiệu ứng hover chỉ dành cho thiết bị có chuột – không ảnh hưởng điện thoại */
@media (hover: hover) {
  .nut--chinh:hover { background: var(--ngoc-dam); }
  .nut--vien:hover { background: var(--muc); color: #fff; }
  .thong-diep .nut--chinh:hover, .tro-choi .nut--chinh:hover { background: #fff; }
  .tro-choi .nut--vien:hover { background: #fff; color: var(--muc); }
  .menu-ngang a:not([aria-current="page"]):hover { background: var(--giay-dam); }
  .the-th:hover { transform: translateY(-3px); border-color: var(--tim); }
  .the-bai:hover { transform: translateY(-3px); box-shadow: var(--bong-do); }
  .the-bai:hover .the-bai__anh img { transform: scale(1.04); }
  .phuong-an button:hover:not([aria-pressed="true"]) { border-color: var(--tim); }
  .tro-choi__lua-chon button:hover:not(:disabled) { border-color: #fff; }
  .nut-chep:hover { background: var(--tim-dam); color: #fff; }
  .bo-loc button:hover:not([aria-pressed="true"]) { border-color: var(--muc); }
}

/* Tôn trọng người dùng chọn “giảm chuyển động” */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
  .cau-noi__cung path { stroke-dashoffset: 0; }
  .cau-noi__tim { transform: translate(-50%, -2px) scale(1); }
}