/* =========================
   Base
========================= */

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family:
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        Roboto,
        Helvetica,
        Arial,
        sans-serif;

    line-height: 1.7;
    color: #263b3a;
    background: #f7faf9;
}

a {
    color: inherit;
}


/* =========================
   Navigation
========================= */

header {
    background: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid #dce9e6;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

nav {
    max-width: 1000px;
    margin: 0 auto;

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 1.1rem 2rem;
}

.logo {
    font-size: 1.1rem;
    font-weight: 600;
    color: #193b3a;
    text-decoration: none;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: #58706e;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: #397f7a;
}


/* =========================
   General Sections
========================= */

section {
    max-width: 1000px;
    margin: 0 auto;
    padding: 5rem 2rem;
}

.eyebrow {
    color: #4d918b;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.16em;
    margin-bottom: 0.8rem;
}


/* =========================
   About / Hero
========================= */

.hero {
    min-height: 75vh;

    display: flex;
    align-items: center;

    background:
        linear-gradient(
            135deg,
            #f7faf9 0%,
            #eef7f6 100%
        );

    max-width: none;
    padding: 6rem 2rem;
}

.hero-content {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: clamp(3rem, 7vw, 5rem);
    line-height: 1.05;
    color: #193b3a;
    font-weight: 650;
    margin-bottom: 1.2rem;
}

.subtitle {
    font-size: 1.35rem;
    color: #4d7472;
    margin-bottom: 1.8rem;
}

.bio {
    max-width: 680px;
    color: #627674;
    margin-bottom: 1rem;
}

.button {
    display: inline-block;

    margin-top: 1.5rem;
    padding: 0.75rem 1.2rem;

    background: #397f7a;
    color: white;

    text-decoration: none;
    border-radius: 5px;

    font-size: 0.9rem;
    font-weight: 600;

    transition:
        background 0.2s ease,
        transform 0.2s ease;
}

.button:hover {
    background: #2e6965;
    transform: translateY(-1px);
}


/* =========================
   Intro Section
========================= */

.intro-section {
    max-width: 800px;
}

.intro-section h2 {
    color: #193b3a;
    font-size: 2rem;
    margin-bottom: 1rem;
}

.intro-section p:not(.eyebrow) {
    color: #627674;
    max-width: 700px;
}

.text-link {
    display: inline-block;
    margin-top: 1.5rem;

    color: #397f7a;
    text-decoration: none;
    font-weight: 600;
}

.text-link:hover {
    text-decoration: underline;
}


/* =========================
   Research Page Header
========================= */

.page-header {
    padding-top: 6rem;
    padding-bottom: 3rem;
}

.page-header h1 {
    font-size: 3rem;
    color: #193b3a;
    margin-bottom: 0.8rem;
}

.page-header > p:last-child {
    color: #627674;
    max-width: 600px;
}


/* =========================
   Research Projects
========================= */

.projects {
    padding-top: 1rem;
}

.project-card {
    background: white;
    border: 1px solid #dce9e6;
    border-radius: 8px;

    margin-bottom: 1rem;

    transition:
        border-color 0.2s ease,
        box-shadow 0.2s ease;
}

.project-card:hover {
    border-color: #a8cbc6;
}

.project-card[open] {
    border-color: #9bc3be;
    box-shadow: 0 5px 20px rgba(40, 90, 85, 0.06);
}


/* The clickable project heading */

.project-card summary {
    list-style: none;
    cursor: pointer;

    display: grid;
    grid-template-columns: 60px 1fr 30px;
    align-items: center;

    padding: 1.4rem 1.5rem;
}

.project-card summary::-webkit-details-marker {
    display: none;
}

.project-number {
    color: #72a9a4;
    font-size: 0.8rem;
    font-weight: 600;
}

.project-title {
    color: #264846;
    font-size: 1.1rem;
    font-weight: 600;
}

.expand {
    color: #72a9a4;
    font-size: 1.4rem;
    text-align: right;

    transition: transform 0.2s ease;
}

.project-card[open] .expand {
    transform: rotate(45deg);
}


/* Expanded content */

.project-content {
    border-top: 1px solid #e5efed;
    padding: 1.5rem 1.5rem 1.7rem 5.25rem;
    max-width: 850px;
}

.project-content p {
    color: #647876;
    margin-bottom: 1rem;
}


/* Tags */

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;

    margin-top: 1.3rem;
}

.tags span {
    background: #edf6f5;
    color: #4d817d;

    padding: 0.3rem 0.65rem;

    border-radius: 20px;

    font-size: 0.75rem;
}


/* =========================
   Footer
========================= */

footer {
    border-top: 1px solid #dce9e6;

    text-align: center;

    padding: 2rem;

    color: #8a9b99;
    font-size: 0.8rem;
}


/* =========================
   Mobile
========================= */

@media (max-width: 600px) {

    nav {
        padding: 1rem 1.2rem;
    }

    .nav-links {
        gap: 1rem;
    }

    section {
        padding-left: 1.2rem;
        padding-right: 1.2rem;
    }

    .hero {
        padding: 5rem 1.2rem;
    }

    .hero h1 {
        font-size: 3rem;
    }

    .subtitle {
        font-size: 1.1rem;
    }

    .page-header h1 {
        font-size: 2.4rem;
    }

    .project-card summary {
        grid-template-columns: 40px 1fr 25px;
        padding: 1.2rem;
    }

    .project-content {
        padding: 1.2rem;
    }
}