/* reset browser's css */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
/* main */
html, body {
    font-family: 'Courier', Courier, monospace;
    line-height: 1.7em;
} 
a {
    color: #444444;
    text-decoration: none;
}
h1 {
    padding-bottom: 20px;
} 

/*  container basic style */
.container {
    margin: auto;
    max-width: 1100px;
    padding: 0 20px;
    overflow: auto;
} 

/* navigation bar */
#navbar {
    background: #E0F1F5;
    color: #444444;
    overflow: auto;
} 
#navbar a {
    color: #444444;
} 
#navbar ul {
    float: right;
    list-style: none;
} 
#navbar ul li {
    float: left;
} 
#navbar ul li a {
    display: block;
    padding: 20px;
    text-align: center;
} 
#navbar ul li a:hover, #navbar ul li a.current {
    background: #D1EAF0;
    color: #444444;
    transition: 0.3s;
} 
#navbar h1 {
    padding-top: 20px;
    float: left;
} 

/* navigation bar dropdown menu */
.dropdown-content {
    display: none;
    position: absolute;
    background-color: #E0F1F5;
    min-width: 160px;
    z-index: 1;
} 
.dropdown:hover .dropdown-content {
    display: block;
} 

/* home page showcase */
#showcase {
    background: url('../img/showcase1.png') no-repeat center center/cover;
    background-size: cover;
    height: 750px;
}
#showcase .showcase-content {
    color: #444444;
    text-align: center;
    padding-top: 200px;
}
#showcase .showcase-content h1 {
    font-size: 60px;
    line-height: 1.3em;
}

/* boxes menu */
.containerr {
    display: flex;
    justify-content: space-around;
    padding: 20px;
    background-color: #F5F5F5;
} 
.box {
    width: 30%;
    max-width: 500px;
    position: relative;
    overflow: hidden;
    margin: 0 10px;
} 
.box img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: opacity 0.4s ease-in-out;
} 
.box:hover img {
    opacity: 0.7;
} 
.box::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: black;
    opacity: 0;
    transition: opacity 0.4s ease-in-out;
  }
.box:hover::before {
    opacity: 1;
}
.overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    text-align: center;
    font-size: 35px;
    padding: 10px 20px;
    display: none;
} 
.box:hover .overlay {
    display: block;
} 

/* tab showcase */
#showcase2 {
    background: url(../img/showcase2.png) no-repeat center center/cover;
    background-size: cover;
    height: 300px;
} 
#showcase2 .showcase2-content {
    color: #444444;
    text-align: left;
    padding-top: 100px;
}
#showcase2 .showcase2-content h1 {
    font-size: 60px;
    line-height: 1.3em;
}

/* content page container */
.containerrr {
    display: flex;
    justify-content: space-between;
    background-color: #F5F5F5;
} 

/* formulas */
.formulas-box {
    width: 40%;
    background-color: white;
    color: #444444;
    border: 1px solid black;
} 
.formulas-box img {
    width: 100%;
    height: 100%;
    object-fit: cover;
} 

/* content */
.content {
    width: 60%;
    background-color: #F5F5F5;
    margin-left: 20px;
    padding: 20px;
} 

/* footer */
footer {
    text-align: center;
    background: #E0F1F5;
    color: #444444;
    padding: 10px;
    border-radius: 5px;
}