/* ==========================================================================
   chat.css — Widget chat CSKH (Telegram) cho trang portfolio
   Nạp sau portfolio.css để dùng chung token màu, radius, shadow.
   ========================================================================== */

#chat-box {
  --chat-gap: 1.25rem;
  --chat-w: 384px;
  --chat-h: 580px;
  --chat-fab: 58px;

  position: fixed;
  right: max(var(--chat-gap), env(safe-area-inset-right));
  bottom: max(var(--chat-gap), env(safe-area-inset-bottom));
  z-index: 130;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.85rem;
  pointer-events: none;
}

#chat-box > * { pointer-events: auto; }

/* ------------------------------- Nút nổi --------------------------------- */
#chat-toggle {
  position: relative;
  width: var(--chat-fab);
  height: var(--chat-fab);
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  box-shadow:
    0 18px 38px -14px color-mix(in srgb, var(--accent) 85%, transparent),
    0 4px 12px -4px rgba(0, 0, 0, 0.45),
    inset 0 1px 0 rgba(255, 255, 255, 0.35);
  transition: transform 0.28s var(--ease), box-shadow 0.28s var(--ease),
              opacity 0.24s var(--ease);
}

#chat-toggle:hover {
  transform: translateY(-3px);
  box-shadow:
    0 24px 46px -16px color-mix(in srgb, var(--accent) 95%, transparent),
    0 6px 16px -6px rgba(0, 0, 0, 0.5),
    inset 0 1px 0 rgba(255, 255, 255, 0.35);
}

#chat-toggle:active { transform: translateY(-1px) scale(0.97); }

#chat-toggle .chat-toggle__icon {
  display: block;
  transform: translateY(1px);
  filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.25));
}

#chat-badge {
  position: absolute;
  top: -4px;
  right: -4px;
  min-width: 22px;
  height: 22px;
  padding: 0 6px;
  display: grid;
  place-items: center;
  border: 2px solid var(--bg);
  border-radius: 999px;
  background: #ef4444;
  color: #fff;
  font-size: 0.72rem;
  font-weight: 700;
  line-height: 1;
  box-shadow: 0 6px 14px -6px rgba(239, 68, 68, 0.9);
}

#chat-badge[hidden] { display: none; }

/* Ẩn nút nổi khi panel mở */
#chat-panel.open + #chat-toggle {
  opacity: 0;
  transform: translateY(10px) scale(0.8);
  pointer-events: none;
}

/* ------------------------------- Khung chat ------------------------------- */
#chat-panel {
  position: absolute;
  right: 0;
  bottom: calc(100% + 0.85rem);
  width: var(--chat-w);
  max-width: calc(100vw - 2 * var(--chat-gap));
  height: min(var(--chat-h), calc(100dvh - 7.5rem));
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--border-strong);
  border-radius: 22px;
  background: color-mix(in srgb, var(--bg-alt) 94%, transparent);
  backdrop-filter: blur(22px) saturate(150%);
  -webkit-backdrop-filter: blur(22px) saturate(150%);
  box-shadow:
    var(--shadow-lg),
    0 0 0 1px color-mix(in srgb, var(--accent) 16%, transparent),
    0 0 60px -18px color-mix(in srgb, var(--accent) 55%, transparent);
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px) scale(0.97);
  transform-origin: bottom right;
  transition: opacity 0.28s var(--ease), transform 0.28s var(--ease),
              visibility 0.28s var(--ease);
}

#chat-panel.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
}

/* -------------------------------- Header ---------------------------------- */
#chat-header {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.85rem 0.9rem;
  border-bottom: 1px solid var(--border);
  background:
    radial-gradient(120% 140% at 0% 0%, color-mix(in srgb, var(--accent) 26%, transparent), transparent 62%),
    radial-gradient(120% 140% at 100% 0%, color-mix(in srgb, var(--accent-2) 20%, transparent), transparent 60%),
    color-mix(in srgb, var(--bg-alt) 70%, transparent);
}

#chat-header .chat-avatar {
  flex: none;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  font-size: 1.15rem;
  box-shadow: 0 10px 22px -10px var(--accent);
}

#chat-header .chat-info {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  min-width: 0;
}

#chat-header .chat-info strong {
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

#chat-header .chat-session {
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.68rem;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

#chat-header .chat-close {
  margin-left: auto;
  flex: none;
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border: 1px solid transparent;
  border-radius: 10px;
  background: transparent;
  color: var(--muted);
  font-size: 1.4rem;
  line-height: 1;
  cursor: pointer;
  transition: color 0.2s, background 0.2s, border-color 0.2s;
}

#chat-header .chat-close:hover {
  color: var(--text);
  background: var(--surface-strong);
  border-color: var(--border);
}

/* ------------------------------- Tin nhắn --------------------------------- */
#chat-messages {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  padding: 0.95rem;
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: var(--border-strong) transparent;
  background:
    radial-gradient(80% 50% at 50% 0%, color-mix(in srgb, var(--accent) 8%, transparent), transparent 70%);
}

#chat-messages::-webkit-scrollbar { width: 8px; }
#chat-messages::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 99px;
}
#chat-messages::-webkit-scrollbar-track { background: transparent; }

#chat-messages .chat-msg {
  max-width: 84%;
  padding: 0.58rem 0.78rem;
  border-radius: 15px;
  font-size: 0.89rem;
  line-height: 1.5;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  animation: chat-pop 0.28s var(--ease) both;
}

#chat-messages .chat-msg .chat-time {
  display: block;
  margin-top: 0.2rem;
  font-size: 0.64rem;
  line-height: 1.2;
  opacity: 0.65;
  text-align: right;
}

#chat-messages .chat-msg.admin {
  align-self: flex-start;
  border: 1px solid var(--border);
  border-bottom-left-radius: 5px;
  background: var(--surface-strong);
  color: var(--text);
}

#chat-messages .chat-msg.admin .chat-time { text-align: left; }

#chat-messages .chat-msg.user {
  align-self: flex-end;
  border-bottom-right-radius: 5px;
  background: linear-gradient(120deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 10px 24px -14px color-mix(in srgb, var(--accent) 90%, transparent);
}

#chat-messages .chat-msg.system {
  align-self: center;
  max-width: 94%;
  padding: 0.42rem 0.8rem;
  border: 1px solid color-mix(in srgb, var(--accent) 26%, transparent);
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--text);
  font-size: 0.8rem;
  text-align: center;
}

#chat-messages .chat-msg.system .chat-time { text-align: center; opacity: 0.55; }

/* Hiệu ứng "đang nhập" */
#chat-messages .chat-typing {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0.62rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 15px;
  border-bottom-left-radius: 5px;
  background: var(--surface-strong);
}

#chat-messages .chat-typing i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--muted);
  animation: chat-typing 1.1s infinite ease-in-out;
}

#chat-messages .chat-typing i:nth-child(2) { animation-delay: 0.15s; }
#chat-messages .chat-typing i:nth-child(3) { animation-delay: 0.3s; }

@keyframes chat-pop {
  from { opacity: 0; transform: translateY(7px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes chat-typing {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.45; }
  30% { transform: translateY(-4px); opacity: 1; }
}

/* ------------------------------- Soạn tin --------------------------------- */
#chat-form {
  display: flex;
  align-items: flex-end;
  gap: 0.55rem;
  padding: 0.75rem;
  padding-bottom: calc(0.75rem + env(safe-area-inset-bottom));
  border-top: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 55%, transparent);
}

#chat-input {
  flex: 1;
  min-height: 42px;
  max-height: 132px;
  padding: 0.62rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface);
  color: var(--text);
  font: inherit;
  font-size: 0.9rem;
  line-height: 1.45;
  resize: none;
  overflow-y: auto;
  outline: none;
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
}

#chat-input::placeholder { color: var(--muted); }

#chat-input:focus {
  border-color: color-mix(in srgb, var(--accent) 60%, transparent);
  background: var(--surface-strong);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

#chat-send {
  flex: none;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 13px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  font-size: 1.05rem;
  line-height: 1;
  cursor: pointer;
  box-shadow: 0 10px 22px -12px var(--accent);
  transition: transform 0.22s var(--ease), opacity 0.22s, box-shadow 0.22s;
}

#chat-send:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 16px 28px -14px var(--accent);
}

#chat-send:active:not(:disabled) { transform: translateY(0); }

#chat-send:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  box-shadow: none;
}

/* ------------------------------ Responsive -------------------------------- */
/* Nút "lên đầu trang" nằm cùng góc phải -> nâng lên trên nút chat. */
.scroll-top { bottom: calc(1.25rem + var(--chat-fab, 58px) + 0.9rem); }

@media (max-width: 600px) {
  body.chat-open { overflow: hidden; }

  #chat-box {
    --chat-gap: 0px;
    right: 0;
    bottom: 0;
    align-items: flex-end;
  }

  #chat-toggle {
    margin: 0 1rem calc(1rem + env(safe-area-inset-bottom));
  }

  #chat-panel {
    position: fixed;
    inset: auto 0 0 0;
    width: 100%;
    max-width: none;
    height: calc(100dvh - var(--kb, 0px));
    max-height: none;
    border-right: 0;
    border-bottom: 0;
    border-left: 0;
    border-radius: 22px 22px 0 0;
    transform: translateY(100%);
    transform-origin: bottom center;
  }

  #chat-panel.open { transform: translateY(0); }

  #chat-panel.open + #chat-toggle { display: none; }

  #chat-header { padding-top: calc(0.85rem + env(safe-area-inset-top)); }

  .scroll-top {
    bottom: calc(1rem + var(--chat-fab, 58px) + env(safe-area-inset-bottom));
  }
}

/* Điện thoại nằm ngang: panel dạng tấm bên phải, cao gần hết màn hình. */
@media (max-width: 940px) and (max-height: 520px) and (orientation: landscape) {
  #chat-box { --chat-gap: 0.75rem; }

  #chat-toggle { margin: 0; }

  #chat-panel {
    position: fixed;
    inset: auto 0.75rem 0.75rem auto;
    width: min(440px, calc(100vw - 1.5rem));
    height: calc(100dvh - var(--kb, 0px) - 1.5rem);
    max-height: none;
    border-radius: 20px;
    transform-origin: bottom right;
  }
}

@media print {
  #chat-box { display: none !important; }
  .scroll-top { bottom: 1.25rem; }
}