/* =========================================================================
   download.css — KHOI TAI VE + YEU CAU HE THONG + NUT VE DAU TRANG
   ========================================================================= */

.dl {
  position: relative;
  border-radius: var(--radius-lg);
  padding: clamp(28px, 4vw, 52px);
  overflow: hidden;
  background: var(--card);
  border: 1px solid var(--border);
  box-shadow: var(--sh-lg);
}

/* Vien mau chay vong quanh. Ve bang lop gia dat duoi (z-index:0) roi phu
   nen len tren, chua o giua 1px lam vien. */
.dl::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(120deg, var(--accent), var(--accent-3), var(--accent-2), var(--accent));
  background-size: 200% 200%;
  animation: mt-sweep 7s linear infinite;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
          mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
          mask-composite: exclude;
  pointer-events: none;
}

.dl__grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, .85fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: center;
}
@media (max-width: 860px) {
  .dl__grid { grid-template-columns: 1fr; }
}

.dl h2 { margin-bottom: .3em; }
.dl__lead { color: var(--text-muted); font-size: var(--fs-lead); }

/* ── Hai nut tai (theo doi Inventor) ─────────────────────── */
.dl__btns { display: grid; gap: 12px; margin: 24px 0 18px; }
@media (min-width: 520px) {
  .dl__btns { grid-template-columns: 1fr 1fr; }
}

/* Nut tai to: dong tren la ban Inventor, dong duoi la dung luong. */
.dlbtn {
  display: grid;
  grid-template-columns: 40px 1fr auto;
  gap: 14px;
  align-items: center;
  text-align: left;
  padding: 14px 18px;
  border-radius: var(--radius);
  border: 1px solid var(--border-strong);
  background: var(--surface-2);
  color: var(--text);
  transition: border-color var(--dur) var(--ease),
              background-color var(--dur) var(--ease),
              transform var(--dur) var(--ease-out),
              box-shadow var(--dur) var(--ease);
}
.dlbtn:hover {
  color: var(--text);
  border-color: var(--accent);
  background: var(--card);
  transform: translateY(-3px);
  box-shadow: var(--sh-md);
}
.dlbtn__ico {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border-radius: 11px;
  background: var(--accent-soft);
  color: var(--accent);
}
.dlbtn__t { font-weight: 700; font-size: .95rem; line-height: 1.25; }
.dlbtn__s { font-size: var(--fs-xs); color: var(--text-faint); }
/* Mui ten nhich sang phai khi tro chuot. */
.dlbtn__arrow { color: var(--text-faint); transition: transform var(--dur) var(--ease-spring), color var(--dur-fast) var(--ease); }
.dlbtn:hover .dlbtn__arrow { transform: translateX(4px); color: var(--accent); }

.dl__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  font-size: var(--fs-xs);
  color: var(--text-faint);
}
.dl__meta code { background: transparent; border: 0; padding: 0; color: var(--text-muted); }

/* ── Bang yeu cau he thong ──────────────────────────────── */
.req {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface-2);
}
.req__row {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 12px;
  padding: 12px 18px;
  font-size: var(--fs-sm);
}
.req__row + .req__row { border-top: 1px solid var(--border); }
.req__k { color: var(--text-faint); }
.req__v { color: var(--text); font-weight: 600; }
@media (max-width: 420px) {
  .req__row { grid-template-columns: 1fr; gap: 2px; }
}

/* ── Nut ve dau trang ───────────────────────────────────── */
/* 🔥 DAY LEN TREN NUT CHAT (03/09/2026).
   Truoc day ca hai cung nam goc phai duoi: .totop o right:22 bottom:22
   z-index:90, con bong bong chat o right:18 bottom:18 z-index:150 va rong
   54px. Chat nam DE LEN va cao hon, nen nut "len dau trang" gan nhu khong
   bam duoc — hien ra roi nhung cu bam la trung vao chat.
   Nay xep chong: chat duoi, totop tren no. 18 + 54 + 18 = 90. */
.totop {
  position: fixed;
  right: 24px; bottom: 90px;
  z-index: 90;
  width: 46px; height: 46px;
  display: grid; place-items: center;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--card);
  color: var(--accent);
  cursor: pointer;
  box-shadow: var(--sh-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px) scale(.9);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease-spring), visibility var(--dur);
}
.totop.is-on { opacity: 1; visibility: visible; transform: none; }
.totop:hover { background: var(--accent-solid); color: var(--accent-fg); border-color: transparent; }