Html 正在尝试围绕引导转盘上的文本创建框容器

我有一些文字在我的图像顶部为我的旋转木马如下所示

我想在文本周围添加一个不透明的框，这样更容易阅读。我试过一些东西，但盒子开始缩小，形状变得很奇怪

这是我的旋转木马的html：

<!-- Carousel -->
<header id="myCarousel" class="carousel slide carousel-fade" data-ride="carousel">
     <!-- Indicators -->
    <ol class="carousel-indicators">
        <li data-target="#myCarousel" data-slide-to="0" class="active"></li>
        <li data-target="#myCarousel" data-slide-to="1"></li>
        <li data-target="#myCarousel" data-slide-to="2"></li>
    </ol>

    <!-- Wrapper for Slides -->
    <div class="carousel-inner" role="listbox">
        <div class="item active">
            <!-- Set the first background image using inline CSS below. -->
            <img src="img/golden_egg3.jpg" class="img-responsive first-slide" alt="First slide">
                <div class="container">
                    <div class="carousel-caption">
                        <div class="caption-one">
                            <h1>The right Wealth Advisor can make a big difference.</h1>
                            <br>
                            <a href="contact.html" class="btn btn-primary btn-lg hvr-underline-from-left" role="button">Learn More</a>
                        </div>
                    </div>
                </div>
        </div>

        <div class="item">
            <!-- Set the first background image using inline CSS below. -->
            <img src="img/graph_in_hand3.jpg" class="img-responsive second-slide" alt="Second slide">
                <div class="container">
                    <div class="carousel-caption">
                        <div class="caption-two">
                            <h1>Personal Wealth Planning is not<br> just charts and graphs, it's about<br> taking control of your financial future.</h1>
                            <a class="btn btn-lg btn-primary hvr-underline-from-left" href="contact.html" role="button">Learn More</a>
                        </div>
                    </div>
                </div>
        </div>

        <div class="item">
            <!-- Set the first background image using inline CSS below. -->
            <img src="img/jar_with_coins3.jpg" class="img-responsive third-slide" alt="Third slide">
                <div class="container">
                    <div class="carousel-caption">
                        <div class="caption-three">
                            <h1>Successful investing takes<br> time, discipline and patience.</h1>
                            <a class="btn btn-lg btn-primary hvr-underline-from-left" href="contact.html" role="button">Learn More</a>
                        </div>
                    </div>
                </div>
        </div>
    </div>
    <a class="left carousel-control" href="#myCarousel" role="button" data-slide="prev">
    <span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
    <span class="sr-only">Previous</span>
  </a>
  <a class="right carousel-control" href="#myCarousel" role="button" data-slide="next">
    <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
    <span class="sr-only">Next</span>
  </a>
</header>

这就是我得到的：

看起来不错，但肯定会更好。在手机上：

---

更糟。我不知道为什么我的按钮这么大，因为我在联系人页面上使用了同样的按钮，而且它的缩放效果非常好。非常感谢您的帮助。

我对您的代码做了一些更改，希望能奏效

.carousel标题{
背景色:#282828 ;；
不透明度：0.75；
}
@介质（最大宽度：768px）{
h1{
字体大小：14px；
}
}

合适的财富顾问可以带来巨大的不同。

.caption-one {
      background-color: #282828;
      opacity: 0.75;
      padding-left: 2%;
      margin-right: 38%;
      padding-bottom: 2%;
      width: 40%;
}