body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background-color: #e5ddd5;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  padding: 10px; 
  box-sizing: border-box;
}

.chat-container {
  width: 100%;
  max-width: 500px;
  height: 90vh;
  background-color: #fff;
  border-radius: 10px;
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.2);
  overflow: hidden;
  position: relative;
  display: flex;
  flex-direction: column;
}

.username-overlay {
  position: absolute;
  background: rgba(255, 255, 255, 0.95);
  width: 100%;
  height: 100%;
  z-index: 10;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 20px;
  box-sizing: border-box;
}

.username-overlay input {
  padding: 12px;
  font-size: 16px;
  margin-top: 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
  width: 100%;
  max-width: 300px;
  box-sizing: border-box;
}
.chat-header {
  background-color: #183847;
  color: white;
  font-weight: bold;
  text-align: center;
  font-size: 18px;
  padding: 15px 20px;
  border-bottom: 1px solid #bba800;
  user-select: none;
}


.username-overlay button {
  margin-top: 15px;
  padding: 12px 25px;
  background-color: #0088cc;
  color: #fff;
  border: none;
  border-radius: 6px;
  font-size: 16px;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.username-overlay button:hover {
  background-color: #005f99;
}

.chat-box {
  flex: 1;
  padding: 15px;
  overflow-y: auto;
  background-color: #f7f7f7;
  display: flex;
  flex-direction: column;
  gap: 10px;
  scroll-behavior: smooth;
}


.msg, .own-msg, .info {
  padding: 10px 14px;
  border-radius: 20px;
  max-width: 70%;
  word-wrap: break-word;
  font-size: 15px;
  box-sizing: border-box;
}

.msg {
  background-color: #dcf8c6;
  align-self: flex-start;
}

.own-msg {
  background-color: #aed2ff;
  align-self: flex-end;
}

.info {
  background-color: transparent;
  color: gray;
  font-size: 13px;
  text-align: center;
  max-width: 100%;
}


.message-form {
  display: flex;
  border-top: 1px solid #ccc;
  padding: 10px;
  background: #f0f0f0;
  box-sizing: border-box;
}

.message-form input {
  flex: 1;
  padding: 12px 15px;
  border-radius: 20px;
  border: 1px solid #ccc;
  outline: none;
  font-size: 15px;
  box-sizing: border-box;
}

.message-form input::placeholder {
  color: #999;
}

.message-form button {
  margin-left: 10px;
  padding: 12px 25px;
  background-color: #0088cc;
  border: none;
  border-radius: 20px;
  color: white;
  font-weight: bold;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.message-form button:hover {
  background-color: #005f99;
}


@media (max-width: 480px) {
  body {
    height: 100%;
    padding: 0;
  }

  .chat-container {
    height: 100vh;
    border-radius: 0;
    box-shadow: none;
  }

  .username-overlay input {
    width: 90%;
  }

  .message-form button {
    padding: 12px 15px;
    margin-left: 5px;
  }

  .msg, .own-msg {
    max-width: 85%;
    font-size: 14px;
  }

  .info {
    font-size: 12px;
    padding: 6px 10px;
  }
}

@media (min-width: 481px) and (max-width: 768px) {
  .chat-container {
    max-width: 400px;
    height: 85vh;
  }

  .msg, .own-msg {
    max-width: 75%;
  }

  .message-form button {
    padding: 12px 20px;
  }
}