/* ============================================================
   CSS VARIABLES
   ============================================================ */
:root {
    --primary: #C9A96E;
    --primary-dim: rgba(201, 169, 110, 0.10);
    --primary-glow: rgba(201, 169, 110, 0.28);
    --bg: #07111e;
    --bg-card: #0b1828;
    --bg-card-hover: #0f1f32;
    --bg-section-alt: #090f1a;
    --border: rgba(255,255,255,0.07);
    --border-hover: rgba(201, 169, 110, 0.38);
    --text: #b8cceb;
    --text-muted: #5e7a94;
    --text-heading: #e8dfc8;

    --fs-xs: 0.72rem;
    --fs-sm: 0.85rem;
    --fs-base: 1rem;
    --fs-lg: 1.1rem;
    --fs-xl: 1.25rem;
    --fs-2xl: 1.5rem;
    --fs-3xl: 1.9rem;
    --fs-4xl: 2.2rem;
    --fs-hero: clamp(2.4rem, 6vw, 3.8rem);

    --font-display: 'Syne', sans-serif;
    --font-body: 'DM Sans', sans-serif;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;

    --shadow-card: 0 4px 28px rgba(0,0,0,0.5);
    --shadow-glow: 0 0 32px rgba(201, 169, 110, 0.10);
    --transition: 0.25s ease;
}

/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    font-family: var(--font-body);
    color: var(--text);
    line-height: 1.7;
    font-size: var(--fs-base);
    background-color: var(--bg);
    background-image: radial-gradient(circle, rgba(255,255,255,0.025) 1px, transparent 1px);
    background-size: 28px 28px;
}

/* ============================================================
   ACCESSIBILITY
   ============================================================ */
a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 3px;
    border-radius: var(--radius-sm);
}

/* ============================================================
   SCROLL REVEAL
   ============================================================ */
.reveal {
    opacity: 0;
    transform: translateY(22px);
    transition: opacity 0.55s ease, transform 0.55s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-stagger > *:nth-child(1) { transition-delay: 0.05s; }
.reveal-stagger > *:nth-child(2) { transition-delay: 0.12s; }
.reveal-stagger > *:nth-child(3) { transition-delay: 0.19s; }
.reveal-stagger > *:nth-child(4) { transition-delay: 0.26s; }
.reveal-stagger > *:nth-child(5) { transition-delay: 0.33s; }
.reveal-stagger > *:nth-child(6) { transition-delay: 0.40s; }
.reveal-stagger > *:nth-child(7) { transition-delay: 0.47s; }
.reveal-stagger > *:nth-child(8) { transition-delay: 0.54s; }

/* ============================================================
   LAYOUT
   ============================================================ */
.container { max-width: 1100px; margin: auto; padding: 0 24px; }
.section { padding: 96px 0; }

.bg-alt {
    background-color: var(--bg-section-alt);
    background-image: radial-gradient(circle, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 28px 28px;
}

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

.section-title {
    text-align: center;
    margin-bottom: 56px;
    font-family: var(--font-display);
    font-size: var(--fs-4xl);
    font-weight: 700;
    color: var(--text-heading);
    letter-spacing: -0.02em;
    display: block;
    width: 100%;
}

.section-title::after {
    content: '';
    display: block;
    width: 36px;
    height: 3px;
    background: var(--primary);
    margin: 10px auto 0;
    border-radius: 2px;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
.nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(7, 17, 30, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    padding: 14px 0;
    z-index: 1000;
}

.nav-container { display: flex; justify-content: space-between; align-items: center; }

.logo-text {
    font-family: var(--font-display);
    color: var(--primary);
    font-weight: 800;
    font-size: var(--fs-xl);
    letter-spacing: -0.01em;
}

.nav-links { display: flex; list-style: none; align-items: center; }

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    margin-left: 28px;
    font-weight: 500;
    font-size: var(--fs-sm);
    letter-spacing: 0.02em;
    transition: color var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -3px; left: 0;
    width: 0; height: 1.5px;
    background: var(--primary);
    transition: width var(--transition);
}

.nav-links a:hover { color: var(--primary); }
.nav-links a:hover::after { width: 100%; }

.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    border-radius: var(--radius-sm);
}

.hamburger-line {
    display: block;
    width: 22px; height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: transform 0.3s, opacity 0.3s;
}

.nav-toggle[aria-expanded="true"] .hamburger-line:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .hamburger-line:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .hamburger-line:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   HERO
   ============================================================ */
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(28px); }
    to   { opacity: 1; transform: translateY(0); }
}
@keyframes orbPulse {
    0%, 100% { opacity: 0.5; transform: scale(1); }
    50%       { opacity: 0.9; transform: scale(1.08); }
}

.hero-banner {
    background-color: var(--bg);
    color: white;
    padding: 200px 0 130px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero-banner::before,
.hero-banner::after {
    content: '';
    position: absolute;
    border-radius: 50%;
    pointer-events: none;
}

.hero-banner::before {
    width: 550px; height: 550px;
    background: radial-gradient(circle, rgba(201,169,110,0.07) 0%, transparent 68%);
    top: -120px; left: -120px;
    animation: orbPulse 8s ease-in-out infinite;
}

.hero-banner::after {
    width: 420px; height: 420px;
    background: radial-gradient(circle, rgba(201,169,110,0.05) 0%, transparent 68%);
    bottom: -80px; right: -60px;
    animation: orbPulse 8s 4s ease-in-out infinite;
}

.hero-banner .container { position: relative; z-index: 1; }

.hero-banner h1 {
    font-family: var(--font-display);
    font-size: var(--fs-hero);
    font-weight: 800;
    line-height: 1.1;
    color: var(--text-heading);
    letter-spacing: -0.03em;
    animation: fadeUp 0.7s ease both;
}

.subtitle {
    color: var(--primary);
    font-size: var(--fs-3xl);
    margin: 14px 0;
    font-weight: 300;
    letter-spacing: 0.01em;
    animation: fadeUp 0.7s 0.15s ease both;
}

.hero-description {
    margin: 18px 0 38px;
    color: var(--text-muted);
    font-size: var(--fs-sm);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    animation: fadeUp 0.7s 0.3s ease both;
}

.hero-buttons { animation: fadeUp 0.7s 0.45s ease both; }

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
    padding: 13px 32px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 500;
    font-family: var(--font-body);
    display: inline-block;
    margin: 8px;
    font-size: var(--fs-sm);
    letter-spacing: 0.03em;
    transition: background-color var(--transition), border-color var(--transition),
                color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.btn:hover { transform: translateY(-2px); }

.btn-primary {
    background: var(--primary);
    color: #0d0a05;
    border: 1.5px solid var(--primary);
    font-weight: 600;
}

.btn-primary:hover {
    background: #dbbe85;
    border-color: #dbbe85;
    box-shadow: 0 8px 28px rgba(201,169,110,0.35);
}

.btn-secondary {
    border: 1.5px solid rgba(255,255,255,0.18);
    color: var(--text);
    background: transparent;
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 8px 28px rgba(201,169,110,0.12);
}

.btn-ghost {
    border: 1.5px solid transparent;
    color: var(--text-muted);
    background: transparent;
}

.btn-ghost:hover {
    color: var(--primary);
    border-color: rgba(201,169,110,0.2);
}

.btn i { margin-right: 6px; font-size: 0.8em; }

/* ============================================================
   FILTER BAR
   ============================================================ */
.filter-bar {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
    margin-bottom: 40px;
}

.filter-btn {
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 8px 20px;
    border-radius: 24px;
    font-size: var(--fs-xs);
    font-family: var(--font-body);
    font-weight: 500;
    letter-spacing: 0.04em;
    cursor: pointer;
    transition: border-color var(--transition), color var(--transition),
                background var(--transition), box-shadow var(--transition);
}

.filter-btn:hover { border-color: var(--border-hover); color: var(--primary); }

.filter-btn.active {
    background: var(--primary-dim);
    border-color: rgba(201,169,110,0.4);
    color: var(--primary);
    box-shadow: 0 0 14px rgba(201,169,110,0.1);
}

/* ============================================================
   PROJECTS GRID
   ============================================================ */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    align-items: stretch;
}

.project-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
    padding: 28px;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
    transition: border-color var(--transition), box-shadow var(--transition),
                background var(--transition), transform var(--transition),
                opacity 0.3s ease;
}

.project-card p {
    font-size: var(--fs-sm);
    color: var(--text);
    line-height: 1.75;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 1.5px;
    background: linear-gradient(90deg, transparent, var(--primary), transparent);
    opacity: 0;
    transition: opacity var(--transition);
}

.project-card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-card), var(--shadow-glow);
    background: var(--bg-card-hover);
    transform: translateY(-4px);
}

.project-card:hover::before { opacity: 1; }

.project-card .tags { margin-top: auto; padding-top: 16px; }
.project-card .link { margin-top: 12px; flex-shrink: 0; }

.project-card.featured {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto 1fr auto;
    column-gap: 40px;
    align-items: start;
    border-color: rgba(201,169,110,0.2);
    background: linear-gradient(135deg, #0b1828 0%, #0f1e32 100%);
    padding: 36px;
}

.project-card.featured p {
    display: block;
    overflow: visible;
}

.project-card.featured::before { opacity: 0.5; }

.project-card.featured .card-header { grid-column: 1 / -1; margin-bottom: 20px; }
.project-card.featured p { grid-column: 1; grid-row: 2; }
.project-card.featured .tags {
    grid-column: 2; grid-row: 2;
    margin-top: 0; padding-top: 0;
    align-content: start;
}

.project-card.hidden-by-filter,
.project-card.hidden-by-more { display: none; }

.no-results {
    grid-column: 1 / -1;
    text-align: center;
    color: var(--text-muted);
    font-size: var(--fs-sm);
    padding: 48px 0;
    display: none;
}
.no-results.visible { display: block; }

/* ============================================================
   CARD SHARED ELEMENTS
   ============================================================ */
.card-header { margin-bottom: 14px; }

.card-header i {
    font-size: 1.4rem;
    color: var(--primary);
    margin-bottom: 10px;
    display: block;
    opacity: 0.85;
}

.card-header h3 {
    font-family: var(--font-display);
    font-size: var(--fs-lg);
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -0.01em;
}

.project-card p {
    font-size: var(--fs-sm);
    color: var(--text);
    line-height: 1.75;
}

.project-card strong,
.edu-card strong,
.experience-item strong {
    color: var(--primary);
    font-weight: 500;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.tag {
    background: var(--primary-dim);
    color: var(--primary);
    padding: 3px 11px;
    border-radius: 20px;
    font-size: var(--fs-xs);
    font-weight: 500;
    letter-spacing: 0.02em;
    border: 1px solid rgba(201,169,110,0.14);
}

.link {
    display: inline-block;
    margin-top: 16px;
    color: var(--primary);
    font-weight: 500;
    text-decoration: none;
    font-size: var(--fs-sm);
    transition: letter-spacing var(--transition);
    letter-spacing: 0.01em;
}
.link:hover { letter-spacing: 0.05em; }

/* ============================================================
   SHOW MORE
   ============================================================ */
.show-more-wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    margin-top: 36px;
}

.btn-show-more {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 11px 28px;
    border-radius: var(--radius-md);
    font-size: var(--fs-sm);
    font-family: var(--font-body);
    font-weight: 500;
    letter-spacing: 0.03em;
    cursor: pointer;
    transition: border-color var(--transition), color var(--transition),
                box-shadow var(--transition), transform var(--transition);
}

.btn-show-more:hover {
    border-color: var(--border-hover);
    color: var(--primary);
    box-shadow: 0 0 18px rgba(201,169,110,0.12);
    transform: translateY(-1px);
}

.btn-show-more i {
    font-size: 0.7rem;
    transition: transform 0.3s ease;
}

.btn-show-more[aria-expanded="true"] i { transform: rotate(180deg); }
.btn-show-more.force-hidden { display: none; }

.show-more-count {
    color: var(--text-muted);
    font-size: var(--fs-xs);
    letter-spacing: 0.04em;
}

/* ============================================================
   EXPERIENCE
   ============================================================ */
.experience-timeline { max-width: 820px; margin: 0 auto; }

.experience-item {
    background: var(--bg-card);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    border-left: 3px solid var(--primary);
    box-shadow: var(--shadow-card);
}

.timeline-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}

.timeline-header h3 {
    font-family: var(--font-display);
    font-size: var(--fs-xl);
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -0.01em;
}

.timeline-header span {
    color: var(--primary);
    font-size: var(--fs-xs);
    font-weight: 500;
    background: var(--primary-dim);
    padding: 5px 13px;
    border-radius: 20px;
    border: 1px solid rgba(201,169,110,0.14);
    white-space: nowrap;
    letter-spacing: 0.02em;
}

.experience-item ul { list-style: none; padding: 0; }

.experience-item li {
    color: var(--text);
    font-size: var(--fs-sm);
    line-height: 1.8;
    margin-bottom: 10px;
    padding-left: 18px;
    position: relative;
}

.experience-item li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary);
    font-size: 0.65rem;
    top: 5px;
}

/* ============================================================
   EDUCATION GRID
   ============================================================ */
.edu-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    max-width: 860px;
    margin: 0 auto;
}

.edu-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    border-top: 3px solid var(--primary);
    box-shadow: var(--shadow-card);
    padding: 32px 28px;
    display: flex;
    flex-direction: column;
    gap: 6px;
    transition: border-color var(--transition), box-shadow var(--transition),
                transform var(--transition), background var(--transition);
    position: relative;
    overflow: hidden;
}

.edu-card::after {
    content: '';
    position: absolute;
    bottom: -30px; right: -30px;
    width: 100px; height: 100px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(201,169,110,0.06) 0%, transparent 70%);
    pointer-events: none;
}

.edu-card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-card), var(--shadow-glow);
    background: var(--bg-card-hover);
    transform: translateY(-3px);
}

.edu-card h3 {
    font-family: var(--font-display);
    font-size: var(--fs-lg);
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 4px;
}

.edu-card p {
    font-size: var(--fs-sm);
    color: var(--text-muted);
    line-height: 1.6;
}

.edu-card p strong { color: var(--text-heading); font-weight: 600; }

/* ============================================================
   CERTIFICATIONS GRID
   ============================================================ */
.certs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 12px;
    max-width: 900px;
    margin: 0 auto;
}

.cert-card {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--bg-card);
    padding: 16px 22px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.cert-card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-glow);
    transform: translateX(4px);
}

.cert-card i {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px; height: 36px;
    border-radius: 50%;
    background: var(--primary-dim);
    border: 1px solid rgba(201,169,110,0.18);
    color: var(--primary);
    font-size: 0.9rem;
    flex-shrink: 0;
}

.cert-info { flex: 1; min-width: 0; }

.cert-info h4 {
    font-family: var(--font-display);
    font-size: var(--fs-sm);
    font-weight: 600;
    color: var(--text-heading);
    margin-bottom: 2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.cert-info span {
    font-size: var(--fs-xs);
    color: var(--text-muted);
}

.cert-year {
    font-size: var(--fs-xs);
    color: var(--primary);
    background: var(--primary-dim);
    border: 1px solid rgba(201,169,110,0.14);
    padding: 3px 10px;
    border-radius: 20px;
    white-space: nowrap;
    flex-shrink: 0;
}

/* ============================================================
   TESTIMONIALS GRID
   ============================================================ */
.testimonial-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.testimonial-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
    padding: 32px;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
    transition: border-color var(--transition), box-shadow var(--transition),
                background var(--transition);
}

.testimonial-card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--shadow-card), var(--shadow-glow);
    background: var(--bg-card-hover);
}

.testimonial-card::before {
    content: '\201C';
    position: absolute;
    top: 12px; right: 24px;
    font-size: 6rem;
    line-height: 1;
    color: var(--primary);
    opacity: 0.08;
    font-family: Georgia, serif;
    pointer-events: none;
}

.testimonial-header {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 18px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}

.testimonial-avatar {
    width: 42px; height: 42px;
    border-radius: 50%;
    background: var(--primary-dim);
    border: 1px solid rgba(201,169,110,0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-display);
    font-size: var(--fs-xs);
    font-weight: 700;
    color: var(--primary);
    flex-shrink: 0;
    letter-spacing: 0.05em;
}

.testimonial-header-text h4 {
    font-family: var(--font-display);
    font-size: var(--fs-base);
    color: var(--text-heading);
    font-weight: 700;
    margin-bottom: 2px;
}

.testimonial-header-text span {
    font-size: var(--fs-xs);
    color: var(--text-muted);
}

.testimonial-body {
    flex: 1;
    font-size: var(--fs-sm);
    color: var(--text);
    line-height: 1.8;
    font-style: italic;
}

.hidden { display: none; }

.read-more-btn {
    background: none;
    border: none;
    color: var(--primary);
    font-weight: 500;
    cursor: pointer;
    margin-top: 16px;
    padding: 0;
    font-size: var(--fs-xs);
    font-family: var(--font-body);
    letter-spacing: 0.07em;
    text-transform: uppercase;
    transition: letter-spacing var(--transition);
    align-self: flex-start;
}

.read-more-btn:hover { letter-spacing: 0.12em; }

/* ============================================================
   CONTACT
   ============================================================ */
.contact-links {
    display: flex;
    justify-content: center;
    gap: 14px;
    margin-top: 12px;
}

.contact-icon-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 52px; height: 52px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 1.15rem;
    text-decoration: none;
    transition: border-color var(--transition), color var(--transition),
                box-shadow var(--transition), transform var(--transition);
}

.contact-icon-link:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 0 22px rgba(201,169,110,0.28);
    transform: translateY(-3px);
}

.contact-phone {
    margin-top: 20px;
    color: var(--text-muted);
    font-size: var(--fs-sm);
}

.contact-phone i { color: var(--primary); margin-right: 8px; }

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    padding: 36px 0;
    text-align: center;
    font-size: var(--fs-xs);
    letter-spacing: 0.05em;
}

/* ============================================================
   RESPONSIVE — TABLET (max 900px)
   ============================================================ */
@media (max-width: 900px) {
    .projects-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .project-card.featured {
        grid-column: 1 / -1;
        grid-template-columns: 1fr;
        grid-template-rows: auto;
        height: auto;
    }

    .project-card.featured .card-header { grid-column: 1; }
    .project-card.featured p { grid-column: 1; grid-row: auto; }
    .project-card.featured .tags {
        grid-column: 1; grid-row: auto;
        margin-top: auto; padding-top: 16px;
    }

    .testimonial-grid { grid-template-columns: 1fr; }
    .edu-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .section { padding: 70px 0; }

    .section-title { font-size: var(--fs-2xl); margin-bottom: 40px; }

    .hero-banner { padding: 140px 0 80px; }
    .subtitle { font-size: var(--fs-2xl); }

    .nav-toggle { display: flex; }

    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: rgba(7,17,30,0.97);
        backdrop-filter: blur(16px);
        padding: 10px 0 20px;
        border-top: 1px solid var(--border);
    }

    .nav-links.is-open { display: flex; }
    .nav-links li { width: 100%; }

    .nav-links a {
        display: block;
        margin-left: 0;
        padding: 13px 24px;
        font-size: var(--fs-base);
        border-bottom: 1px solid var(--border);
    }

    .nav-links a::after { display: none; }

    .timeline-header { flex-direction: column; gap: 10px; }

    .certs-grid { grid-template-columns: 1fr; }
}

/* ============================================================
   RESPONSIVE — MOBILE (max 480px)
   ============================================================ */
@media (max-width: 480px) {
    .hero-banner { padding: 110px 0 60px; }
    .hero-banner::before, .hero-banner::after { display: none; }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .btn {
        display: block;
        width: 100%;
        max-width: 260px;
        margin: 8px auto;
        text-align: center;
    }

    .hero-buttons {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .project-card,
    .edu-card,
    .testimonial-card,
    .experience-item,
    .cert-card { padding: 20px; }

    .filter-bar { gap: 6px; }
    .filter-btn { padding: 7px 14px; font-size: 0.7rem; }
}

/* ============================================================
   PUBLICATIONS
   ============================================================ */
.publication-card {
    max-width: 860px;
    margin: 0 auto;
    border-radius: var(--radius-lg);
    border: 1px solid rgba(201, 169, 110, 0.22);
    border-top: none;
    box-shadow: var(--shadow-card), var(--shadow-glow);
    padding: 40px;
    display: flex;
    flex-direction: column;
    gap: 24px;
    background: linear-gradient(140deg, #0b1828 0%, #0f1e32 100%);
    position: relative;
    overflow: hidden;
    transition: transform var(--transition), box-shadow var(--transition);
}

.publication-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent 0%, var(--primary) 40%, var(--primary) 60%, transparent 100%);
    opacity: 0.8;
}

.publication-card::after {
    content: '';
    position: absolute;
    bottom: -60px; right: -60px;
    width: 220px; height: 220px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(201,169,110,0.07) 0%, transparent 70%);
    pointer-events: none;
}

.publication-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-card), 0 0 48px rgba(201, 169, 110, 0.18);
}

.publication-top {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.publication-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--primary-dim);
    border: 1px solid rgba(201, 169, 110, 0.25);
    border-radius: 20px;
    padding: 6px 14px;
}

.publication-badge i {
    font-size: 0.85rem;
    color: var(--primary);
}

.publication-badge span {
    font-size: var(--fs-xs);
    font-weight: 600;
    color: var(--primary);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.publication-chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 5px 12px;
    font-size: var(--fs-xs);
    color: var(--text-muted);
    letter-spacing: 0.02em;
}

.publication-chip i {
    font-size: 0.7rem;
    color: var(--primary);
}

.publication-body h3 {
    font-family: var(--font-display);
    font-size: var(--fs-2xl);
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.35;
}

.publication-meta {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.publication-authors {
    font-size: var(--fs-sm);
    color: var(--text-muted);
}

.publication-authors strong {
    color: var(--primary);
    font-weight: 600;
}

.publication-venue {
    font-size: var(--fs-sm);
    color: var(--text-muted);
    font-style: italic;
}

.publication-contribution {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    background: rgba(201,169,110,0.05);
    border: 1px solid rgba(201,169,110,0.12);
    border-left: 3px solid var(--primary);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    padding: 16px 20px;
}

.publication-contribution i {
    color: var(--primary);
    font-size: 0.9rem;
    margin-top: 3px;
    flex-shrink: 0;
}

.publication-contribution p {
    font-size: var(--fs-sm);
    color: var(--text);
    line-height: 1.75;
    margin: 0;
}

.publication-footer {
    display: flex;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
    padding-top: 4px;
    border-top: 1px solid var(--border);
}

.publication-doi {
    font-size: var(--fs-xs);
    color: var(--text-muted);
    letter-spacing: 0.02em;
    font-family: monospace;
}

@media (max-width: 600px) {
    .publication-card {
        padding: 24px;
        gap: 18px;
    }

    .publication-body h3 {
        font-size: var(--fs-xl);
    }

    .publication-footer {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
}