/* --- DESIGN CONFIGURATION --- */
:root {
    --sidebar-bg: #1e3a8a;
    --sidebar-text: #ffffff;
    --main-bg: #ffffff;
    --text-color: #333333;
    --link-color: #2563eb;
    --heading-font: 'Playfair Display', serif;
    --body-font: 'Roboto', sans-serif;
    --sidebar-width: 400px;
}

/* Reset & Base */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: var(--body-font);
    color: var(--text-color);
    background-color: var(--main-bg);
    display: flex;
    min-height: 100vh;
    line-height: 1.6;
}
a { text-decoration: none; color: inherit; transition: 0.2s; }
a:hover { color: var(--link-color); }
ul { list-style: none; }

/* --- SIDEBAR --- */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    position: fixed;
    height: 100vh;
    left: 0;
    top: 0;
    padding: 3rem 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    z-index: 1000;
}

.profile-img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid rgba(255,255,255,0.2);
    margin-bottom: 1.5rem;
}

.sidebar h1 {
    font-family: var(--heading-font);
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    letter-spacing: 0.5px;
}

.sidebar p {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.8);
    margin-bottom: 2rem;
    line-height: 1.5;
}

.social-icons {
    display: flex;
    gap: 15px;
    margin-top: auto;
    margin-bottom: 2rem;
}

.social-icons a {
    color: rgba(255,255,255,10);
    font-size: 2.0rem;
    transition: 0.3s;
}

.social-icons a:hover {
    color: #fff;
    transform: translateY(-5px);
}

.copyright {
    font-size: 0.75rem;
    color: rgba(255,255,255,0.4);
    margin-top: auto;
}

/* --- MAIN CONTENT AREA --- */
.main-content {
    margin-left: var(--sidebar-width);
    flex: 1;
    padding: 3rem 3%;
    max-width: 100%;
    width: 100%;
}

/* Top Navigation */
.top-nav {
    margin-bottom: 4rem;
    padding: 1rem 3% 1rem 3%;
    border-bottom: 1px solid #eee;
    position: sticky;
    top: 0;
    background-color: rgba(255, 255, 255, 0.95);
    z-index: 100;
    backdrop-filter: blur(5px);
    margin-left: -3%;
    margin-right: -3%;
    width: 106%;
}

.top-nav ul {
    display: flex;
    gap: 25px;
}

.top-nav a {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    color: #555;
    letter-spacing: 1px;
    cursor: pointer;
}

.top-nav a.active { color: var(--link-color); border-bottom: 2px solid var(--link-color); }

/* Page Sections */
.page-section { display: none; animation: fadeIn 0.4s ease; }
.page-section.active { display: block; }

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.publication-year {
    font-size: 1.5rem;
    font-weight: 700;
    color: #1e3a8a;
    border-bottom: 2px solid #eee;
    padding-bottom: 0.5rem;
    margin: 1.0rem 0 1.0rem 0;
}

.publication-item {
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid #e0e0e0;
}

.publication-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

h2.section-title {
    font-size: 1.8rem;
    color: #111;
    margin: 3rem 0 1.5rem 0;
    border-bottom: 1px solid #eee;
    padding-bottom: 0.5rem;
}

h2.section-title:first-child { margin-top: 0; }

/* --- RESEARCH STYLE --- */
.publication-item { margin-bottom: 1.5rem; }
.publication-item .title { font-weight: 700; color: #222; display: block; }
.publication-item .meta { color: #555; font-size: 0.95rem; }
.publication-item a.doi { color: var(--link-color); font-size: 0.85rem; margin-left: 5px; }

/* --- POSTS STYLE --- */
.posts-year { font-size: 1.5rem; font-weight: 700; color: #ccc; margin: 2rem 0 1rem 0; }
.post-item { display: flex; align-items: baseline; margin-bottom: 0.8rem; }
.post-date { width: 100px; font-size: 0.9rem; color: #888; flex-shrink: 0; }
.post-link { font-weight: 600; color: #333; }
.post-link:hover { text-decoration: underline; color: var(--link-color); }

/* --- HOME & ABOUT STYLE --- */
.intro-text { font-size: 1.1rem; color: #444; margin-bottom: 2rem; }
.btn-link {
    display: inline-block;
    margin-top: 1rem;
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--link-color);
}

/* READ MORE / LESS STYLES */
.more-content {
    display: none;
}

.read-more-btn {
    color: var(--link-color);
    cursor: pointer;
    font-weight: 700;
    font-size: 0.9rem;
    margin-left: 3px;
}

.read-more-btn:hover {
    text-decoration: underline;
}

.highlight-box {
    margin-top: 10px;
    padding: 10px;
    background: #f8fafc;
    border-left: 4px solid #d4af37;
    border-radius: 4px;
}

.msc-course {
    background: #eef2ff;
    color: #1e3a8a;
    padding: 4px 10px;
    border-radius: 15px;
    font-size: 0.85rem;
    border: 1px solid #dbeafe;
}

.bsc-key-coursework {
    background: #f0fdf4;
    color: #166534;
    padding: 4px 10px;
    border-radius: 15px;
    font-size: 0.85rem;
    border: 1px solid #dcfce7;
}

.technical-skills {
    background: #f1f5f9;
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 600;
    color: #334155;
    border: 1px solid #e2e8f0;
}

.skill-category {
    margin-bottom: 2.5rem;
}

.skill-category h4 {
    font-size: 1.4rem;
    color: #333;
    margin-bottom: 1.5rem;
    font-weight: 300;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
    display: inline-block;
    min-width: 200px;
}

.skill-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); /* Creates responsive columns */
    gap: 25px 50px; /* row-gap column-gap */
}

.skill-item {
    margin-bottom: 10px;
}

.skill-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    color: #444;
}

.progress-bg {
    width: 100%;
    height: 6px;
    background-color: #f1f5f9;
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    border-radius: 8px;
    background: linear-gradient(90deg, #2563eb, #28a745);
}

/* --- RESPONSIVE --- */
@media (max-width: 900px) {
    body { flex-direction: column; }
    .sidebar {
        position: relative;
        width: 100%;
        height: auto;
        padding: 2rem 1rem;
    }
    .main-content { margin-left: 0; padding: 2rem 1.5rem; }
    .top-nav { overflow-x: auto; white-space: nowrap; }
}
/* --- TRAVEL DIARY STYLES --- */
.filter-container {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 8px 24px;
    border: 1px solid #e2e8f0;
    background: #fff;
    color: #555;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.filter-btn:hover, .filter-btn.active {
    background: #1e3a8a; /* Your primary blue */
    color: white;
    border-color: #1e3a8a;
    box-shadow: 0 4px 10px rgba(30, 58, 138, 0.2);
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.gallery-item {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s ease;
    border: 1px solid #f1f5f9;
}

.gallery-item:hover {
    transform: translateY(-5px);
}

.gallery-img {
    width: 100%;
    height: 220px;
    object-fit: cover;
    cursor: zoom-in; /* Shows the user they can click */
    transition: opacity 0.2s;
}

.gallery-img:hover {
    opacity: 0.9;
}

.gallery-info {
    padding: 20px;
}

/* Location Link Styling */
.gallery-location {
    font-size: 0.85rem;
    color: #2563eb;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: 8px;
    display: inline-flex;
    align-items: center;
    text-decoration: none;
    cursor: pointer;
    transition: color 0.2s;
}

.gallery-location:hover {
    color: #1e3a8a;
    text-decoration: underline;
}

.gallery-location i {
    margin-right: 6px;
    font-size: 1rem;
}

.gallery-date {
    font-size: 0.8rem;
    color: #94a3b8;
    margin-bottom: 12px;
    display: block;
    font-weight: 500;
}

.gallery-caption {
    font-size: 1.1rem;
    color: #475569;
    line-height: 1.6;
    font-family: 'Caveat', cursive; /* The change */
}

.hide-item {
    display: none;
}

/* --- LIGHTBOX (FULL SCREEN POPUP) --- */
.lightbox {
    display: none; /* Hidden by default */
    position: fixed;
    z-index: 9999; /* Sit on top of everything */
    padding-top: 50px;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(5px);
}

.lightbox-content {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 1000px;
    max-height: 80vh;
    object-fit: contain;
    border-radius: 4px;
    box-shadow: 0 0 20px rgba(255,255,255,0.1);
    animation: zoomIn 0.3s;
}

@keyframes zoomIn {
    from {transform:scale(0)}
    to {transform:scale(1)}
}

.close-lightbox {
    position: absolute;
    top: 20px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: 0.3s;
    cursor: pointer;
}

.close-lightbox:hover,
.close-lightbox:focus {
    color: #bbb;
    text-decoration: none;
    cursor: pointer;
}