/* ==========================================================
   Sigma Theta – Global Stylesheet
   One CSS file for all pages
   Light theme, Σθ brand, blue+earth-tone accents
   ========================================================== */

/* --- Colour scheme --- */
:root {
    --bg: #f8fafc;
    --text: #111827;
    --primary: #1d4ed8;       /* Sigma Theta blue */
    --accent: #b45309;        /* brown/dust */
    --border: #e5e7eb;
    --muted: #6b7280;
    --nav-bg: #ffffff;
}

/* --- Base --- */
body {
    margin: 0;
    background: var(--bg);
    font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
    color: var(--text);
    line-height: 1.6;
}

/* --- Header / Nav --- */
header {
    background: var(--nav-bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: .75rem 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: baseline;
    gap: .3rem;
    text-decoration: none;
}

.logo-symbol {
    font-family: "Times New Roman", serif;
    font-size: 1.7rem;
    font-weight: 700;
    color: var(--primary);
}

.logo-symbol sub {
    font-size: .65em;
}

.logo-text {
    font-family: "Times New Roman", serif;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary); /* Now correctly blue */
}

/* --- Navigation Links --- */
nav ul {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    gap: .75rem;
}

nav a {
    padding: .35rem .60rem;
    border-radius: 999px;
    color: var(--text);
    text-decoration: none;
    white-space: nowrap;
}

nav a.active {
    background: var(--primary);
    color: white !important;
}

nav a:hover {
    background: #e0ebff;
}

/* --- Layout --- */
main {
    max-width: 1100px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

h1 {
    font-size: 2.2rem;
    margin-bottom: 1rem;
}

h2 {
    font-size: 1.4rem;
    margin-top: 2rem;
}

p {
    margin: .6rem 0 1rem;
}

/* --- Hero Image (Home + Others) --- */
.hero {
    display: grid;
    grid-template-columns: 3fr 2.4fr;
    gap: 2rem;
    align-items: center;
}

.hero-image-wrapper {
    border: 1px solid var(--border);
    border-radius: 1.2rem;
    overflow: hidden;
}

.hero-image {
    width: 100%;
    display: block;
}

/* --- Buttons --- */
.btn {
    padding: .55rem 1.1rem;
    border-radius: 999px;
    font-size: .95rem;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-outline {
    border: 1px solid var(--primary);
    color: var(--primary);
}

/* --- ΔFusion Split Layout --- */
.dfusion-hero {
    display: grid;
    grid-template-columns: 2fr 1.4fr;
    gap: 2rem;
    align-items: center;
    margin-bottom: 2rem;
}

/* ΔFusion large image - auto scale to browser height */
.dfusion-hero-image-wrapper {
    border: 1px solid var(--border);
    border-radius: 1rem;
    overflow: hidden;
    max-height: 80vh;              /* <= never exceed 80% of screen height */
    display: flex;
    justify-content: center;
    align-items: center;
}

.dfusion-hero-image {
    width: 100%;
    height: auto;
    max-height: 80vh;              /* <= auto-scale vertically */
    object-fit: contain;           /* keep the whole globe visible */
}


.dfusion-hero-text {
    background: #fff;
    border: 1px solid var(--border);
    padding: 1.2rem 1.4rem;
    border-radius: .8rem;
    box-shadow: 0 2px 6px rgba(0,0,0,0.05);
}

/* --- Profile image (About page) --- */
.profile-pic {
    float: right;
    margin-left: 1rem;
    margin-bottom: 1rem;
    max-width: 240px;
    border-radius: .8rem;
    border: 1px solid var(--border);
}

/* --- Contact Box --- */
.contact-box {
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 1.5rem;
    background: #fff;
}

/* --- Footer --- */
footer {
    text-align: center;
    padding: 1rem;
    border-top: 1px solid var(--border);
    background: #fff;
    color: var(--muted);
    font-size: .85rem;
}

/* --- Responsive --- */
@media(max-width: 900px) {
    .hero,
    .dfusion-hero {
        grid-template-columns: 1fr;
    }
    .profile-pic {
        float: none;
        display: block;
        margin: 0 auto 1rem;
        max-width: 60%;
    }
}

.pub {
    background: #f8f8f8;
    padding: 15px 20px;
    border-left: 4px solid #4a7eb8;
    margin-bottom: 25px;
}

.pub a {
    color: #2c65a1;
}

.abstract summary {
    cursor: pointer;
    font-weight: bold;
    color: #2c65a1;
}

.abstract p {
    margin-top: 10px;
}

.apa {
    font-size: 0.9rem;
    color: #555;
    margin-top: 10px;
}

/* Hamburger (mobile only) */
.hamburger {
    display: none;
    font-size: 2rem;
    background: none;
    border: none;
    color: #003366;
    cursor: pointer;
    margin-right: 10px;
}

/* Mobile nav menu (initially hidden) */
#nav-menu {
    display: flex;
    gap: 20px;
}

@media (max-width: 800px) {
    .hamburger {
        display: block;
    }
    #nav-menu {
        display: none;
        flex-direction: column;
        background: #ffffff;
        padding: 10px;
        border: 1px solid #00336622;
        margin-top: 10px;
    }
    #nav-menu.show {
        display: flex;
    }
}