/* Giao diện hợp thư đa kênh — CSS thuần, không framework.
   Cố ý không dùng React/Vue: VPS dùng chung với website bán hàng, không cài
   Node để khỏi tốn RAM và khỏi phải build. */

:root {
  --xanh: #4c5bb3;
  --xanh-dam: #3d4a93;
  --xanh-nhat: #eef1fb;
  --nen: #f1f3f9;
  --vien: #e3e6ef;
  --chu: #1f2437;
  --chu-mo: #6b7280;
  --trang: #fff;
  --do: #e5484d;
  --xanh-la: #16a34a;
  --bo-goc: 10px;
  --bong: 0 1px 3px rgba(20, 25, 60, .08);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--nen);
  color: var(--chu);
  font-size: 14px;
}

a { color: var(--xanh); text-decoration: none; }

/* ----------------------------- Thanh trên ----------------------------- */
.thanh-tren {
  background: var(--xanh);
  color: #fff;
  height: 56px;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 20px;
  position: sticky;
  top: 0;
  z-index: 50;
}
.thanh-tren .logo { font-weight: 700; font-size: 17px; letter-spacing: .2px; }
.thanh-tren .day { flex: 1; }
.thanh-tren a { color: #fff; opacity: .9; }
.thanh-tren a:hover { opacity: 1; }
.nguoi-dung {
  display: flex; align-items: center; gap: 8px;
  background: rgba(255, 255, 255, .15);
  padding: 5px 12px; border-radius: 20px;
}
.chu-cai {
  width: 26px; height: 26px; border-radius: 50%;
  background: #fff; color: var(--xanh);
  display: grid; place-items: center; font-weight: 700; font-size: 12px;
}

/* ----------------------------- Khung chung ----------------------------- */
.khung { max-width: 1180px; margin: 20px auto; padding: 0 16px; }
.the {
  background: var(--trang);
  border-radius: var(--bo-goc);
  box-shadow: var(--bong);
  padding: 18px 20px;
  margin-bottom: 16px;
}
h1, h2 { margin: 0 0 14px; font-size: 18px; }

.nut {
  border: 0; border-radius: 8px; padding: 9px 16px;
  background: var(--xanh); color: #fff; font-size: 14px; font-weight: 600;
  cursor: pointer; display: inline-flex; align-items: center; gap: 7px;
}
.nut:hover { background: var(--xanh-dam); }
.nut.phu { background: var(--xanh-nhat); color: var(--xanh); }
.nut.phu:hover { background: #e2e7fa; }
.nut.vien { background: #fff; color: var(--chu); border: 1px solid var(--vien); }
.nut:disabled { opacity: .55; cursor: not-allowed; }

input[type=text], input[type=password], input[type=search] {
  width: 100%; padding: 10px 13px;
  border: 1px solid var(--vien); border-radius: 8px;
  font-size: 14px; background: #fff; color: var(--chu);
}
input:focus { outline: 2px solid var(--xanh-nhat); border-color: var(--xanh); }

.loi {
  background: #fdeced; color: var(--do);
  padding: 10px 13px; border-radius: 8px; margin-bottom: 12px; font-size: 13px;
}
.ok-box {
  background: #e9f7ee; color: #15803d;
  padding: 10px 13px; border-radius: 8px; margin-bottom: 12px; font-size: 13px;
}

/* ----------------------------- Đăng nhập ----------------------------- */
.giua { min-height: 100vh; display: grid; place-items: center; padding: 20px; }
.hop-dang-nhap { width: 100%; max-width: 380px; }
.hop-dang-nhap .the { padding: 26px; }
.hop-dang-nhap label { display: block; margin: 12px 0 5px; font-weight: 600; font-size: 13px; }
.hop-dang-nhap .nut { width: 100%; justify-content: center; margin-top: 18px; }
.tieu-de-app { text-align: center; margin-bottom: 18px; }
.tieu-de-app .ten { font-size: 21px; font-weight: 700; color: var(--xanh); }
.tieu-de-app .mo-ta { color: var(--chu-mo); font-size: 13px; margin-top: 4px; }
.doi-che-do { text-align: center; margin-top: 14px; font-size: 13px; color: var(--chu-mo); }

/* ----------------------------- Thẻ shop ----------------------------- */
.tabs { display: flex; gap: 6px; align-items: center; }
.tab {
  display: flex; align-items: center; gap: 8px;
  padding: 9px 15px; border-radius: 8px; cursor: pointer;
  font-weight: 600; color: var(--chu-mo); background: transparent; border: 0; font-size: 14px;
}
.tab.chon { background: var(--xanh-nhat); color: var(--xanh); }
.dem {
  background: var(--xanh); color: #fff; border-radius: 20px;
  padding: 1px 8px; font-size: 12px; font-weight: 700;
}
.tab:not(.chon) .dem { background: #d8dced; color: var(--chu-mo); }

.luoi-shop {
  display: grid; gap: 14px;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
}
.the-shop {
  border: 2px solid var(--vien); border-radius: var(--bo-goc);
  padding: 15px; background: #fff; cursor: pointer;
  display: flex; gap: 13px; align-items: center; transition: .15s;
  position: relative;
}
.the-shop:hover { border-color: var(--xanh); box-shadow: var(--bong); }
.the-shop.chon { border-color: var(--xanh); background: #f7f9ff; }
.anh-shop {
  width: 46px; height: 46px; border-radius: 8px; flex: none;
  background: var(--xanh-nhat); color: var(--xanh);
  display: grid; place-items: center; font-weight: 700; font-size: 16px;
}
.the-shop .ten { font-weight: 600; margin-bottom: 3px; }
.the-shop .phu { color: var(--chu-mo); font-size: 12.5px; display: flex; align-items: center; gap: 5px; }
.huy-hieu-chua-doc {
  position: absolute; top: 10px; right: 12px;
  background: var(--do); color: #fff; border-radius: 20px;
  padding: 2px 8px; font-size: 11.5px; font-weight: 700;
}
.tick {
  position: absolute; top: 10px; right: 12px;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--xanh); color: #fff; display: grid; place-items: center; font-size: 12px;
}

/* ----------------------------- Hộp thoại (modal) ----------------------------- */
.lop-phu {
  position: fixed; inset: 0; background: rgba(23, 28, 56, .45);
  display: grid; place-items: center; z-index: 100; padding: 20px;
}
.hop-thoai {
  background: #fff; border-radius: 14px; width: 100%; max-width: 720px;
  max-height: 85vh; display: flex; flex-direction: column;
}
.hop-thoai .dau {
  padding: 18px 22px; border-bottom: 1px solid var(--vien);
  display: flex; align-items: center; justify-content: space-between;
}
.hop-thoai .than { padding: 18px 22px; overflow: auto; flex: 1; }
.hop-thoai .chan {
  padding: 14px 22px; border-top: 1px solid var(--vien);
  display: flex; justify-content: space-between; align-items: center;
}
.dong-x { background: 0; border: 0; font-size: 22px; cursor: pointer; color: var(--chu-mo); line-height: 1; }

/* ----------------------------- Hợp thư 3 cột ----------------------------- */
/* Trang hợp thư: KHOÁ cuộn toàn trang, chỉ cho cuộn BÊN TRONG từng cột.
   Nếu không khoá, cuộn chuột sẽ kéo cả trang làm thanh trên biến mất. */
body.trang-hop-thu { height: 100vh; overflow: hidden; }

.hop-thu {
  display: grid;
  grid-template-columns: 240px 330px 1fr;
  height: calc(100vh - 56px);
  overflow: hidden;
}
/* min-height/min-width: 0 là BẮT BUỘC: ô lưới (grid item) và ô flex mặc định
   có min-size = auto nên KHÔNG co nhỏ hơn nội dung -> cột bị đội cao, tràn ra
   ngoài và overflow-y của .than-cot không bao giờ có tác dụng. */
.cot {
  border-right: 1px solid var(--vien);
  display: flex; flex-direction: column;
  min-width: 0; min-height: 0; overflow: hidden;
}
.cot:last-child { border-right: 0; }
.cot .dau-cot {
  padding: 13px 15px; border-bottom: 1px solid var(--vien);
  background: #fff; font-weight: 600; display: flex; align-items: center;
  justify-content: space-between; gap: 8px; min-height: 52px;
}
.cot .than-cot { overflow-y: auto; flex: 1; min-height: 0; background: #fff; }

.muc-shop {
  padding: 11px 15px; cursor: pointer; display: flex; align-items: center;
  gap: 10px; border-left: 3px solid transparent; font-size: 13.5px;
}
.muc-shop:hover { background: var(--nen); }
.muc-shop.chon { background: var(--xanh-nhat); border-left-color: var(--xanh); font-weight: 600; }
.muc-shop .so { margin-left: auto; color: var(--chu-mo); font-size: 12px; }

.muc-ht {
  padding: 12px 15px; border-bottom: 1px solid #f1f2f7; cursor: pointer;
  display: flex; gap: 11px;
}
.muc-ht:hover { background: #fafbff; }
.muc-ht.chon { background: var(--xanh-nhat); }
.avatar {
  width: 40px; height: 40px; border-radius: 50%; flex: none;
  background: #dfe3f3; color: var(--xanh); display: grid; place-items: center;
  font-weight: 700; font-size: 14px; overflow: hidden;
}
.avatar img { width: 100%; height: 100%; object-fit: cover; }
.muc-ht .noi-dung { min-width: 0; flex: 1; }
.muc-ht .hang1 { display: flex; justify-content: space-between; gap: 8px; align-items: baseline; }
.muc-ht .ten { font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.muc-ht .gio { color: var(--chu-mo); font-size: 11.5px; flex: none; }
.muc-ht .xem-truoc {
  color: var(--chu-mo); font-size: 12.5px; margin-top: 2px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.nhan-shop {
  display: inline-block; font-size: 11px; padding: 1px 7px; border-radius: 4px;
  background: var(--xanh-nhat); color: var(--xanh); margin-top: 4px; font-weight: 600;
}
.cham-do {
  width: 8px; height: 8px; border-radius: 50%; background: var(--do); flex: none;
  align-self: center;
}

/* Khung chat */
.khung-chat {
  display: flex; flex-direction: column;
  height: 100%; min-height: 0; background: var(--nen);
}
.chat-than {
  flex: 1; min-height: 0; overflow-y: auto; padding: 18px;
  display: flex; flex-direction: column; gap: 10px;
}
.bong-bong { max-width: 72%; padding: 9px 13px; border-radius: 14px; line-height: 1.45; word-wrap: break-word; }
/* Giống Pancake: khách màu trắng bên trái, shop màu xanh lá nhạt bên phải */
.bong-bong.khach { background: #fff; align-self: flex-start; border-bottom-left-radius: 4px; }
.bong-bong.shop { background: #daf3dc; align-self: flex-end; border-bottom-right-radius: 4px; }
.bong-bong img { max-width: 220px; border-radius: 8px; display: block; }
.bong-bong .gio-nho { font-size: 11px; opacity: .65; margin-top: 4px; }
.bong-bong.he-thong {
  align-self: center; background: #e6e8f2; color: var(--chu-mo);
  font-size: 12px; border-radius: 20px; padding: 5px 13px;
}
.chat-nhap {
  border-top: 1px solid var(--vien); background: #fff; padding: 12px 16px;
  display: flex; gap: 10px; align-items: flex-end;
}
.chat-nhap textarea {
  flex: 1; border: 1px solid var(--vien); border-radius: 10px; padding: 10px 13px;
  font-family: inherit; font-size: 14px; resize: none; max-height: 120px; min-height: 42px;
}
.trong {
  display: grid; place-items: center; height: 100%;
  color: var(--chu-mo); text-align: center; padding: 30px;
}
.dang-tai { padding: 24px; text-align: center; color: var(--chu-mo); font-size: 13px; }

@media (max-width: 900px) {
  .hop-thu { grid-template-columns: 1fr; }
  .cot:not(.cot-chat) { display: none; }
}