:root {
    --html-background: gainsboro;
    --primary-color: #00466d;
    --secondary-color: #0C99AF;
    --tertiary-color: #FFFFFF;
    --font-family: "Roboto", Helvetica, Verdana, Geneva, Tahoma, sans-serif;
    --button-blue-hover: #1e90ff;
    --intercalated-background: #007aff08;
    --text:#333; 
  }

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    color: var(--text);
}

a {
    text-decoration: none;
}

h1, h3, h5, h6 {
    color: var(--primary-color);
}

h2, h4 {
    color: var(--secondary-color);
}

p {
    font-size:smaller;
    line-height: 1.7;
    padding-bottom: 10px;
}

td {
    padding-top: 10px;
    padding-bottom: 10px;
    padding-left: 5px;
    vertical-align: top;
    line-height: 1.7;
}

nav {
    position: relative;
    z-index: 1;
}

ul {
    list-style-type: none;
    padding: 0;
    display: none;
    flex-direction: column;
}

ul.active {
    display: flex;
}

li {
    margin: 10px 0;
    padding-left: 15px;
    position: relative;
}

a {
    text-decoration: none;
    color: #333;
}

a:hover {
    color: var(--primary-color);
    font-weight: bold;
}

/* Modern Projects Dropdown Menu */
ul.submenu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: white;
    min-width: 280px;
    padding: 15px;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.15);
    border: 1px solid rgba(0,0,0,0.08);
    z-index: 1000;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

ul.submenu li {
    margin: 0;
    padding: 0;
}

ul.submenu li a {
    display: flex;
    align-items: center;
    padding: 12px 15px;
    border-radius: 8px;
    color: #333;
    font-weight: 500;
    font-size: 14px;
    transition: all 0.2s ease;
    border-left: 3px solid transparent;
}

ul.submenu li a:hover {
    background: linear-gradient(135deg, rgba(12, 153, 175, 0.1) 0%, rgba(0, 70, 109, 0.1) 100%);
    border-left-color: var(--secondary-color);
    color: var(--primary-color);
    transform: translateX(5px);
}

ul.submenu li a::before {
    content: "→";
    margin-right: 10px;
    color: var(--secondary-color);
    font-weight: bold;
    opacity: 0;
    transform: translateX(-10px);
    transition: all 0.2s ease;
}

ul.submenu li a:hover::before {
    opacity: 1;
    transform: translateX(0);
}

.submenuTitle {
    cursor: pointer;
}

li:hover > ul.submenu,
a.submenuTitle:hover + ul.submenu, 
ul.submenu:hover {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

/* Submenu arrow indicator */
.submenuTitle::after {
    content: "";
    display: inline-block;
    margin-left: 5px;
    transition: transform 0.3s ease;
}

li:hover > .submenuTitle::after {
    transform: rotate(90deg);
}

.imageText {
    color: var(--tertiary-color);
}

.responsive-img {
    width: 100%; /* Image width is 100% of its container */
    height: auto; /* Maintain the aspect ratio */
    max-width: 100%; /* Prevent image from exceeding its original size */
    min-width: 50px;
}

/* General button styles */
.btn {
    font-size: 16px;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    margin-right: 10px; /* Add spacing between buttons */
}

/* Primary button (blue background, white text) */
.btn-primary {
    background-color: var(--secondary-color); /* Blue background */
    color: white; /* White text */
    border: none;
}

/* Outline button (white background, black text with border) */
.btn-outline {
    background-color: white; /* White background */
    color: black; /* Black text */
    border: 2px solid black; /* Black border */
}

/* Hover effect for primary button */
.btn-primary:hover {
    background-color: var(--button-blue-hover); /* Darker blue when hovered */
}

/* Hover effect for outline button */
.btn-outline:hover {
    background-color: black; /* Black background on hover */
    color: white; /* White text on hover */
}

/* Position the image container (needed to position the left and right arrows) */
.container {
    position: relative;
}

/* Hide the images by default */
.mySlides {
    display: none;
}

/* Add a pointer when hovering over the thumbnail images */
.cursor {
    cursor: pointer;
}

/* Next & previous buttons */
.prev, .next {
    cursor: pointer;
    position: absolute;
    top: 40%;
    width: auto;
    padding: 16px;
    margin-top: -50px;
    color: white;
    font-weight: bold;
    font-size: 20px;
    border-radius: 0 3px 3px 0;
    user-select: none;
    -webkit-user-select: none;
}

/* Position the "next button" to the right */
.next {
    right: 0;
    border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover, .next:hover {
    background-color: rgba(0, 0, 0, 0.8);
}

/* Number text (1/3 etc) */
.numbertext {
    color: #f2f2f2;
    font-size: 12px;
    padding: 8px 12px;
    position: absolute;
    top: 0;
}

/* Container for image text */
.caption-container {
    text-align: center;
    background-color: #222;
    padding: 2px 16px;
}

.caption {
    color: white;
}

.row:after {
    content: "";
    display: table;
    clear: both;
}

/* Six columns side by side */
.column {
    float: left;
    width: 16.66%;
}

/* Add a transparency effect for thumnbail images */
.demo {
    opacity: 0.6;
}

.active, .demo:hover {
    opacity: 1;
}

/* Menu hamburger */
.menu-icon {
    display: block;
    font-size: 30px;
    cursor: pointer;
    padding-left: 8px;
}

/* Base styles (mobile-first) */
body {
    background-color: white;
    margin: 0 auto;
    width: 100%;
    font-family: var(--font-family);
    font-size: 16px;
    display: grid;
}

figcaption {
    font-size: 12px;
    color: var(--text);
    margin-top: 10px;
    text-align: center;
}

body > footer {
    grid-area: footer;
    min-width: 320px;
    padding: 30px;
}

 /* Floating Button Style */
.scroll-to-top-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    padding: 10px 20px;
    font-size: 18px;
    background-color: var(--secondary-color);    
    color: white; /* Arrow color */
    border: none;
    border-radius: 15px; /* Rounded rectangle */
    cursor: pointer;
    box-shadow: 0px 1px 1px rgba(0, 0, 0, 0.3);
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
  }
  
  /* Show the button when it's visible */
  .scroll-to-top-btn.show {
    opacity: 1;
    visibility: visible;
  }
  
  /* Change the appearance on hover */
  .scroll-to-top-btn:hover {
    background-color: val(--button-blue-hover); /* Orange background on hover */
    color: #ffffff; /* White arrow */
    border: 1px solid #ffffff; /* White border */
  }

  /* Tablet styles */
@media only screen and (min-width: 481px) {
    
    body {
        width: 100%;
        max-width: 960px;
        font-size: 18px;
    }

    nav {
        grid-area: nav;
        min-width: 320px;
        align-items: center;
    }

    ul {
        display: flex;
        flex-direction: row;
        flex-wrap: wrap;
        list-style-type: none;
        justify-content: space-between;
        align-items: center;
        text-align: center;
        padding: 15px;
        padding-right: 30px;
    }

    li {
        margin: 0;
        position: relative;
    }

    ul.submenu {
        /* Inherits modern styles from base */
    }
    
    .menu-icon {
        display: none;
    }

    figcaption {
        font-size: 12px;
    }
    
}

/* Desktop styles */
@media only screen and (min-width: 769px) {

    html {
        background-color: var(--html-background);
    }

    body {
        width: 95%;
        max-width: 1200px;
        font-size: 20px;
    }

    body nav hr {
        display: block;
        width: 100%;
     }
    
    nav {
        grid-area: nav;
        min-width: 320px;
        align-items: center;
        background: linear-gradient(to bottom, var(--intercalated-background) 100%, white)
    }

    ul {
        display: flex;
        flex-direction: row;
        flex-wrap: wrap;
        list-style-type: none;
        justify-content: space-between;
        align-items: center;
        text-align: center;
        padding: 15px;
        padding-right: 30px;
    }

    li {
        margin: 0;
        position: relative;
    }

    ul.submenu {
        /* Inherits modern styles from base */
    }

    .menu-icon {
        display: none;
    }

    figcaption {
        font-size: 14px;
    }

 }