/* generic class properties */

* {
    font-family: 'SF Pro Display', Arial, Helvetica, sans-serif;
}

body {
    margin: 0;
}

.header {
    color: white;
    background-color: rgb(255, 0, 0);
}

.big-header {
    color: white;
    background-color: rgb(255, 0, 0);
}

.main {
    color: black;
    background-color: rgb(255, 255, 255);
}

.nav-menu {
    color: white;
    background-color: rgb(255, 0, 0);
}

/* used to illustrate hover - needs removing later */
p {
    margin-top: 0;
    margin-bottom: 4px;
}

.nav-bar > a {
    text-decoration: none;
    color: white;
}

a {
    text-decoration: none;
    color: red;
}

a:hover {
    color:rgb(255, 174, 0)          /* nasty colour */
}

.nav-dropdown > ul {
    margin: 0px;
    padding: 0px;
    list-style: none;
    font-size: 18px;
    line-height: 2.5em;
    text-align: left;
}

.nav-dropdown > ul > li {
    width: 200px;
    border-top: 1px solid rgb(255, 255, 255);
}

.nav-dropdown > ul > li > a {
    text-decoration: none;
    color: white;
}

.footer > ul {
    display: flex;
    flex-direction: row;
    justify-content: center;
    align-items: center;
    padding: 0;
    margin: 0;
}

.footer > ul {
    list-style: none;
    line-height: 2.5em;
    background-color: red;
}

.footer > ul > li > a {
    text-decoration: none;
    color: white;
    padding-left: 10px;
    padding-right: 10px;
}

svg {
    fill: white;        /* works really well */
}

/* Works on Firefox */
* {
    scrollbar-width: thin;          /* none to hide scrollbar */
    scrollbar-color: blue red;;
  }
  
  /* Works on Chrome, Edge, and Safari */
  *::-webkit-scrollbar {
    width: 12px;
  }
  
  *::-webkit-scrollbar-track {
    background: orange;
  }
  
  *::-webkit-scrollbar-thumb {
    background-color: blue;
    border-radius: 20px;
    border: 3px solid orange;
  }

.content_section {
    height: var(--hero-image-height);
}

#home_section01 .hero_image_wrapper {
    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    display: flex;
    justify-content: center;
    position: absolute;
    height: var(--hero-image-height);
    width: 100%;
    top: calc(var(--hero-image-height)*0 + var(--global-navigation-height));         /* Better now! using global variable */
    left: 0;
    padding-top: 0px;
    z-index: 1;
}

#home_section02 .hero_image_wrapper {

    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    display: flex;
    justify-content: center;
    position: absolute;
    height: var(--hero-image-height);
    width: 100%;
    top: calc(var(--hero-image-height)*1 + var(--global-navigation-height));          /* Better now! using global variable */
    left: 0;
    padding-top: 0px;
    z-index: 1;
}

#home_section03 .hero_image_wrapper {

    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    display: flex;
    justify-content: center;
    position: absolute;
    height: var(--hero-image-height);
    width: 100%;
    top: calc(var(--hero-image-height)*2 + var(--global-navigation-height));          /* Better now! using global variable */
    left: 0;
    padding-top: 0px;
    z-index: 1;
}

/* the hero images have to be unique so need to be hard coded in */

#hero_image_home_01 {
    background-image: url("/images/hero_image_home_01.png");
    background-size: 3010px 500px;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    width: 100%;
}

#hero_image_home_02 {
    background-image: url("/images/hero_image_home_02.png");
    background-size: 3010px 580px;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    width: 100%;
}

#hero_image_home_03 {
    background-image: url("/images/hero_image_home_03.png");
    background-size: 3010px 580px;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    width: 100%;
}

/* resources section */

#resources_section01 .hero_image_wrapper {
    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    display: flex;
    justify-content: center;
    position: absolute;
    height: var(--hero-image-height);
    width: 100%;
    top: calc(var(--hero-image-height)*0 + var(--global-navigation-height));         /* Better now! using global variable */
    left: 0;
    padding-top: 0px;
    z-index: 1;
}

#resources_section02 .hero_image_wrapper {

    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    display: flex;
    justify-content: center;
    position: absolute;
    height: var(--hero-image-height);
    width: 100%;
    top: calc(var(--hero-image-height)*1 + var(--global-navigation-height));          /* Better now! using global variable */
    left: 0;
    padding-top: 0px;
    z-index: 1;
}

#hero_image_resources_01 {
    background-image: url("/images/hero_image_resources_01.png");
    background-size: 3010px 580px;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    width: 100%;
}

#hero_image_resources_02 {
    background-image: url("/images/hero_image_resources_02.png");
    background-size: 3010px 580px;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    width: 100%;
}

.page_info {
    position: relative;
    z-index: 2;
}

.headline {
    display: flex;
    justify-content: center;
    padding-top: 11px;
    color: black;
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 32px;
    font-weight: 600;
    line-height: 36px;
}

.sub_heading {
    display: flex;
    justify-content: center;
    margin-top: 4px;
    color: rgb(0, 0, 0);
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 19px;
    font-weight: 400;
    line-height: 23px;
}

.page_links {
    display: flex;
    justify-content: center;
    margin-top: 0.7em;
}

.section_link {
    color: black;
    text-decoration: none;
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 17px;
    font-weight: 400;
    line-height: 21px;
}

.section_link:hover {
    color:rgb(255, 0, 0);
}

/*********************************************************/
/*          page sections for general page              **/
/*********************************************************/

.main_section {
    display: grid;
    place-content: center;
    margin-bottom: 20px;
}

.main_header {
    width: 100%;
    border-bottom: 1px solid black;
    font-size: 18px;
    font-weight: 600;
    line-height: 25px;
    color: black;
    padding-top: 20px;
    padding-bottom: 20px;
    margin-bottom: 0px;
}

.main_content {
    width: 100%;
    font-size: 16px;
    font-weight: normal;
    line-height: 1.2rem;
    color: black;
    padding-top: 20px;
    padding-bottom: 20px;
    margin-bottom: 0px;
}

/* ****************  about section ********************* */
.about_section {
    display: grid;
    place-content: center;
    margin-bottom: 40px;
}

.about_header {
    width: 100%;
    border-bottom: 1px solid black;
    font-size: 21px;
    font-weight: 600;
    line-height: 25px;
    color: black;
    padding-top: 20px;
    padding-bottom: 20px;
    margin-bottom: 0px;
}

#about_section01 .about_image_wrapper {
    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    height: 165px;
    margin-top: 16px;
    margin-bottom: 40px;
    z-index: 1;
}

#about_section02  {
    display: none;              /* switched off for the time being */
}

#about_section02 .about_image_wrapper {

    /* Sort this out - needs to sit up against menu bar at top */
    /* Also needs headline to sit on top */
    height: 165px;
    margin-top: 16px;
    margin-bottom: 40px;
    z-index: 1;
}

#about_image_01 {
    background-image: url("/images/force.svg");
    background-size: 116px 165px;
    background-repeat: no-repeat;
    background-position: center;
    width: 116px;
    height: 165px;
}

#about_image_02 {
    background-image: url("/images/about_image_01.png");
    background-size: 116px 165px;
    background-repeat: no-repeat;
    background-position: center;
    width: 116px;
    height: 165px;
}

.about_list {
    z-index: 2;
    margin: 0px;
    padding: 0px;
    list-style: none;
    text-align: left;
}

.about_list_item {
    padding-top: 11px;
    padding-left: 20px;
    color: black;
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 17px;
    font-weight: 400;
    line-height: 25px;
}

.about_list_item > strong {
    color: black;
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 17px;
    font-weight: 600;
    line-height: 25px;
}

.tel {
    color:rgb(0, 0, 0);
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 17px;
    font-weight: 400;
    line-height: 25px;
}

.email {
    color:rgb(0, 0, 0);
    font-family:'SF Pro Display', Arial, Helvetica, sans-serif;
    font-size: 17px;
    font-weight: 400;
    line-height: 25px;
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    opacity: 0;
    text-align: center;
}

.hero_image_wrapper:hover .overlay {
    opacity: 0.5;
}

/* remove later */
.physical-constants {
    margin-left: 1em;
    margin-right: 1em;
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    padding-bottom: 20px;
    justify-items: center;
}

.physical-constants-header {
    color:rgb(0, 0, 0);
    font-size: 24px;
    text-align: center;
    padding-top: 100px;
    padding-bottom: 20px;
}