:root {
  --app-bg: #eef3f8;
  --panel: #ffffff;
  --line: #dce5ee;
  --text: #17212b;
  --muted: #6f7d8b;
  --primary: #2aabee;
  --primary-dark: #1689c7;
  --mine: #d8f3dc;
  --other: #ffffff;
}

* {
  box-sizing: border-box;
}

body {
  color: var(--text);
  min-height: 100vh;
}

.auth-body {
  background: linear-gradient(135deg, #e4f5ff 0%, #f7fbff 48%, #edf8f1 100%);
}

.auth-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.auth-card {
  width: min(100%, 430px);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 32px;
}

.brand-mark {
  width: 54px;
  height: 54px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--primary);
  font-size: 1.6rem;
}

.chat-body {
  background: var(--app-bg);
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
}

.chat-app {
  height: 100vh;
  height: 100dvh;
  display: grid;
  grid-template-columns: 310px 1fr;
  min-height: 0;
  overflow: hidden;
}

.users-panel {
  background: var(--panel);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
}

.panel-header,
.conversation-header {
  min-height: 72px;
  padding: 16px 18px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.eyebrow {
  color: var(--primary-dark);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

.user-list {
  padding: 10px;
  overflow-y: auto;
  min-height: 0;
}

.user-item {
  width: 100%;
  border: 0;
  background: transparent;
  color: inherit;
  text-align: left;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  border-radius: 8px;
}

.user-item:hover {
  background: #f4f8fb;
}

.user-item.active {
  background: #e6f5fd;
}

.empty-users {
  color: var(--muted);
  margin: 8px;
  font-size: .95rem;
}

.avatar {
  width: 38px;
  height: 38px;
  flex: 0 0 38px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 700;
  background: linear-gradient(135deg, #2aabee, #35c58c);
}

.status-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #35c58c;
  margin-left: auto;
}

.unread-badge {
  min-width: 24px;
  height: 24px;
  padding: 0 7px;
  border-radius: 999px;
  display: inline-grid;
  place-items: center;
  margin-left: auto;
  color: #fff;
  background: var(--primary);
  font-size: .78rem;
  font-weight: 700;
  line-height: 1;
}

.conversation {
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-rows: auto 1fr auto;
  background: #e8f0f7;
  overflow: hidden;
}

.messages {
  padding: 20px;
  overflow-y: auto;
  min-height: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  overscroll-behavior: contain;
}

.empty-chat {
  margin: auto;
  color: var(--muted);
  display: grid;
  place-items: center;
  text-align: center;
  gap: 8px;
  max-width: 280px;
}

.empty-chat i {
  font-size: 2rem;
  color: var(--primary-dark);
}

.empty-chat p {
  margin: 0;
}

.message {
  display: flex;
  max-width: 76%;
  min-width: 0;
}

.message.mine {
  align-self: flex-end;
}

.message-bubble {
  background: var(--other);
  border: 1px solid rgba(23, 33, 43, .06);
  border-radius: 8px;
  padding: 9px 11px;
  box-shadow: 0 1px 1px rgba(0, 0, 0, .04);
  min-width: 0;
  max-width: 100%;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.message.mine .message-bubble {
  background: var(--mine);
}

.message-meta {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 4px;
  color: var(--muted);
  font-size: .8rem;
}

.message-meta strong {
  color: var(--primary-dark);
}

.message p {
  margin: 0;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.message-image {
  display: block;
  max-width: min(320px, 64vw);
  max-height: 320px;
  border-radius: 8px;
  margin-top: 8px;
  object-fit: cover;
}

.composer {
  background: var(--panel);
  border-top: 1px solid var(--line);
  padding: 12px;
  position: relative;
}

.composer-row {
  display: grid;
  grid-template-columns: 44px 44px 1fr 46px;
  gap: 10px;
  align-items: center;
}

.icon-button,
.send-button {
  width: 42px;
  height: 42px;
  border: 0;
  border-radius: 8px;
  display: inline-grid;
  place-items: center;
  color: var(--muted);
  background: transparent;
  font-size: 1.2rem;
  cursor: pointer;
}

.icon-button:hover {
  background: #edf5fb;
  color: var(--primary-dark);
}

.send-button {
  color: #fff;
  background: var(--primary);
}

.send-button:hover {
  background: var(--primary-dark);
}

.send-button:disabled,
.send-button:disabled:hover {
  background: #a9cfe4;
  cursor: not-allowed;
}

.image-preview {
  position: relative;
  width: 150px;
  margin: 0 0 10px 54px;
}

.image-preview img {
  width: 150px;
  height: 100px;
  border-radius: 8px;
  object-fit: cover;
  border: 1px solid var(--line);
}

.image-preview .icon-button {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 30px;
  height: 30px;
  background: rgba(23, 33, 43, .75);
  color: #fff;
  font-size: .9rem;
}

.emoji-picker {
  position: absolute;
  left: 66px;
  bottom: 66px;
  width: min(330px, calc(100vw - 28px));
  max-height: 230px;
  padding: 10px;
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 6px;
  overflow-y: auto;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 12px 28px rgba(23, 33, 43, .16);
  z-index: 5;
}

.emoji-option {
  width: 34px;
  height: 34px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  font-size: 1.25rem;
  line-height: 1;
}

.emoji-option:hover,
.emoji-option:focus {
  background: #edf5fb;
  outline: none;
}

.users-overlay {
  display: none;
}

@media (max-width: 991px) {
  .chat-app {
    grid-template-columns: 1fr;
  }

  .users-panel {
    position: fixed;
    inset: 0 auto 0 0;
    width: min(82vw, 320px);
    z-index: 20;
    transform: translateX(-100%);
    transition: transform .2s ease;
    box-shadow: 0 12px 30px rgba(0, 0, 0, .18);
  }

  .users-panel.open {
    transform: translateX(0);
  }

  .users-overlay.open {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 10;
    border: 0;
    background: rgba(23, 33, 43, .28);
  }

  .message {
    max-width: 92%;
  }
}

@media (max-width: 575px) {
  .auth-card {
    padding: 24px;
  }

  .messages {
    padding: 14px;
  }

  .conversation-header {
    padding: 12px;
  }

  .composer-row {
    grid-template-columns: 40px 40px 1fr 42px;
    gap: 6px;
  }

  .emoji-picker {
    left: 8px;
    right: 8px;
    width: auto;
    grid-template-columns: repeat(6, 1fr);
  }
}