:root {
    --color-red: #85221b;
    --color-black: #0d1117;
    --black-highlight: #161E27;
    --color-white: #f5f5f7;
    --color-blue: #4D7EA8;
    --color-gray: #dddddf;
    /* https://coolors.co/85221b-070707-fefffe-828489-4d7ea8 */

    --color-night: red;
    --color-lavender: #EBEFFF;
    --color-dark-gray: #333333;
    --color-light-gray: #f5f5f5;
}

body {
    line-height: 1.6;
    font-size: 18px;
    color: var(--color-black);
    background-color: var(--color-white);
    transition: background-color 0.5s ease;
    transition: color 0.5s ease;
}
main {
    margin: 100px auto;
    max-width: 1100px;
    width: clamp(300px, 100%, 90vw);
}
section {
    margin-bottom: 32px;
}
h1,h2,h3 {
    line-height: 1.2
}
.bird {
    display: block;
    margin: auto;
    width: calc(5% + 20px);
    transition: filter 0.5s ease;
}

/* navbar */
nav {
    font-family: 'Spinnaker', sans-serif;
    border-bottom:1px solid var(--color-white);
    backdrop-filter: blur(25px);
    background: hsla(0,0,100%,0.75);
    position: fixed;
    top: 0;
    padding: 10px 0;
    width: 98%;
    z-index: 1000;
}

nav.header.scrolled {
    transition: all .4s linear;
    border-bottom: 1px solid var(--color-dark-gray);
}

nav a {
    text-decoration: none;
    color: inherit;
}

nav a .brand {
    padding: 0;
    padding-left: calc(50% - 530px);
    margin: 0;
    height: 38px;
    transition: filter 0.5s ease;
}

nav .menu-collapse {
    float: right;
    position: relative;
    padding: 0;
    padding-right: calc(50% - 550px);
}

nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    height: 40px;
    display: flex;
    align-items: center;
}

nav li {
    line-height: 40px;
}

nav li>a {
    letter-spacing: 2px;
    text-transform: uppercase;
    padding-inline:12px;
    font-size: 16px;
    display: inline-block;
}

.hover-pill {
    position: absolute;
    bottom: 0;
    height: 40px;
    background-color: white;
    border-radius: 20px;
    z-index: -1;
    transition: opacity .4s linear,left .4s ease,width .4s ease;
    opacity: 0;
}

.menu-icon {
    display: none;
    cursor: pointer;
    padding: 10px 4px;
}

.menu-icon .bar1,.menu-icon .bar2,.menu-icon .bar3 {
    width: 18px;
    height: 2px;
    background-color: var(--color-black);
    margin-block:3px;
    transition: .4s;
}

.menu-icon.menu-open .bar1 {
    transform: translate(0,5px)rotate(-45deg);
}

.menu-icon.menu-open .bar2 {
    opacity: 0;
}

.menu-icon.menu-open .bar3 {
    transform: translate(0,-5px)rotate(45deg);
}

/* home */
#about p {
    font-family: Georgia, Times, "Times New Roman", serif;    
}
#about {
    display: block;
    align-items: center;
    gap: 34px;
    margin: 0;
}
#about img {
    width: 100%;
    border-radius: 6px;
}
#about .content {
    padding: 20px 0;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}
#about p {
    text-align: justify;
}

/* Slideshow container */
.slideshow-container {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 75% for 4:3 ratio */
    border-radius: 6px;
    overflow: hidden;
}

/* Slide images */
.slide img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover; 
    border-radius: 6px;
}

/* Caption text */
.caption {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background-color: rgba(0, 0, 0, 0.6);
    color: white;
    padding: 10px;
    font-size: 18px;
    border-radius: 4px;
}

/* Fade animation */
.fade {
    animation: fadeEffect 2s ease;
}

@keyframes fadeEffect {
    from { opacity: 0.4; }
    to { opacity: 1; }
}

/* In-line links */

.inline {
    transition: text-decoration .1s ease-out,color .1s ease-out;
    color: var(--color-black);
    text-decoration: underline var(--color-blue);
    text-underline-offset: 3px;
    text-decoration-thickness: 2.5px;
}

.inline:hover {
    text-decoration: underline var(--color-red);
    text-decoration-thickness: 2.5px;
}

/* Container for the tiles */
#news-section {
    display: grid;
    grid-template-columns: repeat(1, 1fr); /* Two columns */
    gap: 20px; /* Space between the tiles */
}

/* Individual tile styling */
.tile {
    background-color: var(--color-white);
    border: 1px solid var(--color-gray);
    border-radius: 4px;
    padding: 20px;
    box-shadow: 0px 4px 6px var(--color-gray);
    transition: transform 0.3s ease;
}

/* Tile hover effect */
.tile:hover {
    transform: translateY(-2px);
}

/* Tile header, title, date, and link */
.tile-header {
    color: var(--color-blue);  /* Blue color for categories */
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 10px;
}

.tile-title {
    font-size: 18px;
    margin-bottom: 10px;
}

.tile-date {
    font-size: 16px;
    color: var(--color-gray);
    margin-bottom: 15px;
}

.tile-link {
    color: var(--color-black);
    text-decoration: none;
    font-weight: bold;
}

.tile-link:hover {
    text-decoration: underline var(--color-blue);
}

/* Members page styling */

#pi-section, #team-section, #past-team {
    display: grid;
    gap: 20px;
}

#pi-section {
    grid-template-columns: repeat(1, 1fr);
}

#team-section, #past-team {
    grid-template-columns: repeat(2, 1fr);
}

#past-team {
    grid-template-columns: repeat(3, 1fr);
}

#pi-section h2, #team-section h2, #past-team h2 {
    grid-column: 1 / -1;
    font-size: 26px;
    color: var(--color-black); 
    text-align: center;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-bottom: 1px solid var(--color-gray);
    padding: 2.5px 0;
}

#team-section h2, #past-team h2 {
    border-top: 1px solid var(--color-gray);
}

/* Team member card styling */
.pi-member {
    display: flex;
    gap: 20px;
}

.pi-member, .team-member, .past-member {
    background-color: var(--color-white);
    padding: 25px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.pi-member, .past-member {
    text-align: left; 
}

.team-member {
    text-align: center; 
}

.team-member:hover, .pi-member:hover, .past-member:hover {
    background-color: white;
    transform: scale(1.05); 
    box-shadow: 0 8px 16px white; 
}

/* Image styling */
.pi-member img {
    width: 240px;
    height: 240px;
    border-radius: 50%;
    margin: 20px 0 0 0;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.team-member img {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    margin-bottom: 15px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Name styling */
.team-member h3, .pi-member h3, .past-member h3 {
    font-size: 22px;
    color: var(--color-black);
    margin: 15px 0 5px;
    font-weight: bold;
}

.team-member p, .pi-member p, .past-member p {
    font-size: 18px;
    color: var(--color-black);
}

/* Position styling */
.pi-member p:first-of-type, .team-member p:first-of-type {
    font-size: 18px;
    color: var(--color-dark-gray);
    margin: 5px 0;
}

/* Institution styling */
.pi-member p:nth-of-type(2) {
    font-size: 18px;
    color: var(--color-dark-gray);
    margin-bottom: 15px;
}

/* Links styling */
.team-member .links a, .pi-member .links a, .past-member .links a {
    color: var(--color-black);
    font-weight: 500;
    text-decoration: underline var(--color-blue);
    text-decoration-thickness: 3px;
    font-size: 18px;
}

.team-member .links a:hover, .pi-member .links a:hover, .past-member .links a:hover {
    text-decoration: underline var(--color-red);
    text-decoration-thickness: 3px;
}

#bio {
    text-align: justify; /* Justify text for aligned edges */
}

/* Research page styling */
#research h2 {
    font-size: 26px;
    color: var(--color-black); 
    text-align: center;
    margin-bottom: 25px;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-bottom: 1px solid var(--color-gray);
    padding-top: 5px;
    padding-bottom: 5px;
}

#research p {
    text-align: justify;
}

/* Research section headers */
.research-topic h3 {
    color: var(--color-red);
    font-size: 22px;
    margin-bottom: 10px;
    border-bottom: 2px solid var(--color-red);
    padding-bottom: 5px;
}

.research-topic h4 {
    color: var(--color-blue);
    font-size: 20px;
    margin-top: 15px;
    margin-bottom: 10px;
}

.research-topic p {
    text-align: justify;
    line-height: 1.6;
    color: var(--color-black);
    margin-bottom: 10px;
}

.research-topic b {
    color: var(--color-dark-gray);
}

/* Higlight text color */

::selection {
    background-color: var(--color-red);
    color: var(--color-white); /* Adjust text color for contrast */
}

/* Media query for dark themes */
@media (prefers-color-scheme: dark) {
    body {
        color: var(--color-white);
        background-color: var(--color-black);
    }
    .inline {
        color: var(--color-white);
    }
    nav {
        border-bottom: 1px solid var(--color-black);
        background: hsla(0,0,100%,0.75);
    }
    .bird, nav a .brand {
        filter: invert(90%);
    }
    nav.header.scrolled {
        border-bottom: 1px solid var(--color-gray);
    }
    .hover-pill {
        background-color: var(--black-highlight);
    }
    nav a {
        color: var(--color-gray);
    }
    nav li a:hover {
        color: var(--color-white);
    }
    nav li.active a {
        color: var(--color-whitek);
    }
    .menu-icon .bar1, .menu-icon .bar2, .menu-icon .bar3 {
        background-color: var(--color-white);
    }
    #about a {
        color: var(--color-white);
    }
    .tile {
        background-color: var(--color-black);
        border: 1px solid black;
        box-shadow: 0px 4px 6px black;
    }
    .tile-link {
        color: var(--color-white);
    }
    .team-member, .pi-member, .past-member {
        background-color: var(--color-black);
    }
    .team-member:hover, .pi-member:hover, .past-member:hover {
        background-color: var(--black-highlight);
        transform: scale(1.025);
        box-shadow: 0 6px 16px var(--black-highlight); 
    }
    #pi-section h2, #team-section h2, #past-team h2 {
        color: var(--color-white); 
    }
    .team-member h3, .pi-member h3, .past-member h3 {
        color: var(--color-white);
    }
    .team-member p, .pi-member p, .past-member p {
        color: var(--color-white);
    }
    .pi-member p:first-of-type, .team-member p:first-of-type {
        color: var(--color-gray);
    }
    .pi-member p:nth-of-type(2) {
        color: var(--color-light-gray);
    }
    .team-member .links a, .pi-member .links a, .past-member .links a {
        color: var(--color-white);
    }
    #research h2 {
        color: var(--color-white);
        border-bottom: 1px solid var(--color-gray);
    }
    .research-topic p {
        color: var(--color-white);
    }
    .research-topic b {
        color: var(--color-dark-gray);
    }
}

@media (max-width: 799px) {
    body {
        margin: 0;
        max-width: 100%;
        width: 100%;
        padding: 10px 20px;
        box-sizing: border-box; 
    }
    main {
        margin: 0;
        padding: 0;
    }
    .bird {
        padding-bottom: 40px;
    }
    nav {
        position: relative;
        padding: 5px;
        width: 100%;
    }
    nav .menu-collapse {
        height: 0;
        overflow: hidden;
        transition: 0.4s;
        display: block;
    }
    nav .menu-collapse {
        float: none;
    }
    nav .menu-collapse ul {
        margin: 0;
        padding: 0;
    }
    nav .menu-collapse ul li {
        display: block;
        float: none;
    }
    nav .show-menu {
        height: 60px;
    }
    .menu-icon {
        display: block;
        float: right;
    }
    .hover-pill {
        bottom: 20px;
    }    
    #about {
        margin-top: 24px;
        display: block;
        margin-bottom: 32px;
    }
    #about img {
        margin-bottom: -10px;
    }
    #about .content {
        grid-template-columns: 1fr;
    }
    #news-section {
        grid-template-columns: 1fr; /* One column  */
    }
    #team-section, #pi-section, #past-team {
        grid-template-columns: 1fr; /* Single column layout */
    }
    /* Team member card styling */
    .pi-member {
        display: grid;
        text-align: center;
    }
    .team-member, .pi-member, .past-member {
        border: none;
        box-shadow: none;
    }
    .team-member:hover, .pi-member:hover, .past-member:hover {
        background-color: var(--color-white);
        transform: scale(1.025); 
        box-shadow: none;
    }
    /* Image styling for smaller screens */
    .team-member img, .pi-member img {
        width: clamp(150px, 80%, 400px);
        height: auto;
        aspect-ratio: 1 / 1;
        object-fit: cover;
        border-radius: 10%;
        margin: 0;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    }
}

/* Media query for dark themes */
@media (prefers-color-scheme: dark){ 
    @media (max-width: 799px) {
    .team-member:hover, .pi-member:hover, .past-member:hover {
        background-color: var(--color-black);
    }
}}