/* ============================================
   PRUDHVI ANANTHULA — PROFESSIONAL PORTFOLIO
   Clean, Modern, Secure Static Website
   ============================================ */

/* ---------- CSS CUSTOM PROPERTIES ---------- */
:root {
    /* Colors — Professional Navy + Gold */
    --primary: #1a365d;
    --primary-light: #2d4a7a;
    --primary-dark: #0f2440;
    --accent: #c9963b;
    --accent-light: #e8c47a;
    --accent-dark: #a87a2e;

    /* Neutrals */
    --white: #ffffff;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;

    /* Typography */
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-heading: 'Playfair Display', Georgia, serif;

    /* Spacing */
    --section-padding: 100px 0;
    --container-width: 1200px;

    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 14px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
    --shadow-xl: 0 20px 50px rgba(0,0,0,0.15);

    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 50%;
}

/* ---------- RESET & BASE ---------- */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    color: var(--gray-800);
    line-height: 1.7;
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--accent);
}

ul {
    list-style: none;
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------- TYPOGRAPHY ---------- */
h1, h2, h3, h4 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.3;
}

/* ---------- BUTTONS ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.3px;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    text-align: center;
}

.btn svg {
    width: 18px;
    height: 18px;
}

.btn-primary {
    background: var(--accent);
    color: var(--white);
    border-color: var(--accent);
}

.btn-primary:hover {
    background: var(--accent-dark);
    border-color: var(--accent-dark);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border-color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: var(--white);
    transform: translateY(-2px);
}

.btn-outline--light {
    color: var(--white);
    border-color: rgba(255,255,255,0.5);
}

.btn-outline--light:hover {
    background: var(--white);
    color: var(--primary);
    border-color: var(--white);
}

.btn-secondary {
    background: var(--gray-100);
    color: var(--primary);
    border-color: var(--gray-200);
}

.btn-secondary:hover {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
    transform: translateY(-2px);
}

.btn-full {
    width: 100%;
    justify-content: center;
}

/* ============================================
   NAVIGATION
   ============================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 20px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(255,255,255,0.97);
    backdrop-filter: blur(12px);
    padding: 12px 0;
    box-shadow: var(--shadow-sm);
}

.nav-container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--white);
    letter-spacing: 1px;
    transition: var(--transition);
}

.navbar.scrolled .nav-logo {
    color: var(--primary);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-link {
    color: rgba(255,255,255,0.85);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--white);
    background: rgba(255,255,255,0.1);
}

.navbar.scrolled .nav-link {
    color: var(--gray-600);
}

.navbar.scrolled .nav-link:hover {
    color: var(--primary);
    background: var(--gray-50);
}

.nav-link--cta {
    background: var(--accent) !important;
    color: var(--white) !important;
    padding: 8px 24px;
}

.nav-link--cta:hover {
    background: var(--accent-dark) !important;
}

/* Mobile Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--white);
    transition: var(--transition);
    border-radius: 2px;
}

.navbar.scrolled .nav-toggle span {
    background: var(--gray-800);
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
    overflow: hidden;
}

.hero-bg-pattern {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(201,150,59,0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255,255,255,0.04) 0%, transparent 50%);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    padding-top: 100px;
    padding-bottom: 80px;
    position: relative;
    z-index: 1;
}

.hero-greeting {
    color: var(--accent-light);
    font-size: 1.1rem;
    font-weight: 500;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.hero-name {
    font-family: var(--font-heading);
    font-size: 3.8rem;
    font-weight: 700;
    color: var(--white);
    line-height: 1.15;
    margin-bottom: 16px;
}

.hero-title {
    color: var(--accent-light);
    font-size: 1.15rem;
    font-weight: 400;
    letter-spacing: 1px;
    margin-bottom: 24px;
}

.hero-description {
    color: rgba(255,255,255,0.75);
    font-size: 1.05rem;
    line-height: 1.8;
    max-width: 520px;
    margin-bottom: 36px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.hero-social {
    display: flex;
    gap: 16px;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: var(--radius-full);
    border: 1.5px solid rgba(255,255,255,0.2);
    color: rgba(255,255,255,0.7);
    transition: var(--transition);
}

.social-icon:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--white);
    transform: translateY(-3px);
}

.social-icon svg {
    width: 18px;
    height: 18px;
}

/* Hero Image */
.hero-image {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.hero-image-frame {
    position: relative;
    width: 300px;
    height: 300px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    z-index: 2;
    background: transparent;
    border: none;
}

.hero-image-frame img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
    object-position: top center;
}

.hero-image-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    color: rgba(255,255,255,0.4);
    gap: 12px;
}

.placeholder-icon {
    width: 80px !important;
    height: 80px !important;
}

.hero-image-placeholder span {
    font-size: 0.9rem;
    font-weight: 500;
}

/* Hide the old decoration div — replaced by ::after pseudo-element */
.hero-image-decoration {
    display: none;
}

.hero-scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
}

.hero-scroll-indicator a {
    color: rgba(255,255,255,0.5);
    animation: bounce 2s infinite;
}

.hero-scroll-indicator svg {
    width: 28px;
    height: 28px;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-10px); }
    60% { transform: translateY(-5px); }
}

/* ============================================
   SECTION COMMON STYLES
   ============================================ */
.section {
    padding: var(--section-padding);
}

.section--light {
    background: var(--white);
}

.section--dark {
    background: var(--gray-900);
}

.section--accent {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
}

.section--accent-alt {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-label {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 3px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 12px;
}

.section-label--light {
    color: var(--accent-light);
}

.section-title {
    font-size: 2.5rem;
    color: var(--gray-900);
    margin-bottom: 16px;
}

.section-title--light {
    color: var(--white);
}

.section-divider {
    width: 60px;
    height: 3px;
    background: var(--accent);
    margin: 0 auto;
    border-radius: 2px;
}

.section-subtitle {
    color: rgba(255,255,255,0.7);
    font-size: 1.05rem;
    max-width: 560px;
    margin: 20px auto 0;
    line-height: 1.7;
}

.section-cta {
    text-align: center;
    margin-top: 48px;
}

/* ============================================
   ABOUT SECTION
   ============================================ */
.about-grid {
    display: grid;
    grid-template-columns: 1.3fr 0.7fr;
    gap: 60px;
    align-items: start;
}

.about-lead {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 20px;
    line-height: 1.7;
}

.about-text p {
    margin-bottom: 18px;
    color: var(--gray-600);
}

.about-text .btn {
    margin-top: 12px;
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.stat-card {
    background: var(--gray-50);
    border: 1px solid var(--gray-100);
    border-radius: var(--radius-md);
    padding: 28px 20px;
    text-align: center;
    transition: var(--transition);
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent);
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
    margin-bottom: 8px;
}

.stat-number::after {
    content: '+';
    font-size: 1.5rem;
    color: var(--accent);
}

.stat-label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ============================================
   EXPERTISE SECTION
   ============================================ */
.expertise-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.expertise-card {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 36px 28px;
    transition: var(--transition);
}

.expertise-card:hover {
    background: rgba(255,255,255,0.1);
    transform: translateY(-6px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
}

.expertise-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-sm);
    background: rgba(201,150,59,0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: var(--accent-light);
}

.expertise-icon svg {
    width: 26px;
    height: 26px;
}

.expertise-card h3 {
    font-family: var(--font-body);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 10px;
}

.expertise-card p {
    color: rgba(255,255,255,0.6);
    font-size: 0.92rem;
    line-height: 1.7;
}

/* ============================================
   IMPACT SECTION — LIGHT MODE CARD OVERRIDES
   ============================================ */
.section--light .expertise-card {
    background: #fff;
    border: 1px solid rgba(0,0,0,0.08);
    box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.section--light .expertise-card:hover {
    background: #fff;
    box-shadow: 0 8px 28px rgba(0,0,0,0.12);
}

.section--light .expertise-card h3 {
    color: var(--gray-900);
}

.section--light .expertise-card p {
    color: var(--gray-600);
}

.section--light .expertise-icon {
    background: rgba(26, 54, 93, 0.08);
    color: var(--primary);
}

.section--light .expertise-icon svg {
    color: var(--primary);
    stroke: var(--primary);
}

.section--light .tag {
    background: rgba(26, 54, 93, 0.08);
    color: var(--primary);
}

/* ============================================
   PUBLICATIONS SECTION
   ============================================ */
.research-profiles {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 48px;
    flex-wrap: wrap;
}

.profile-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 24px;
    border: 1.5px solid var(--gray-200);
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--gray-600);
    transition: var(--transition);
}

.profile-badge:hover {
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.profile-badge svg {
    width: 18px;
    height: 18px;
}

.publications-list {
    max-width: 800px;
    margin: 0 auto;
}

.publication-card {
    display: grid;
    grid-template-columns: 80px 1fr;
    gap: 28px;
    padding: 32px 0;
    border-bottom: 1px solid var(--gray-100);
    transition: var(--transition);
}

.publication-card:last-child {
    border-bottom: none;
}

.publication-year {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--accent);
    padding-top: 4px;
}

.publication-title {
    font-family: var(--font-body);
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: 6px;
}

.publication-journal {
    font-size: 0.9rem;
    color: var(--gray-500);
    margin-bottom: 4px;
}

.publication-authors {
    font-size: 0.88rem;
    color: var(--gray-400);
    font-style: italic;
    margin-bottom: 10px;
}

.publication-tags {
    display: flex;
    gap: 8px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.tag {
    display: inline-block;
    padding: 3px 12px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
    background: var(--gray-100);
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.publication-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--primary);
}

.publication-link svg {
    width: 14px;
    height: 14px;
}

.publication-link:hover {
    color: var(--accent);
}

/* ============================================
   SPEAKING SECTION
   ============================================ */
.speaking-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.speaking-card {
    background: rgba(255,255,255,0.08);
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid rgba(255,255,255,0.1);
    transition: var(--transition);
}

.speaking-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
}

.speaking-card-media {
    height: 200px;
    overflow: hidden;
}

.speaking-card-media img,
.speaking-card-media iframe {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.speaking-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.04);
    color: rgba(255,255,255,0.3);
    gap: 8px;
}

.speaking-placeholder svg {
    width: 48px;
    height: 48px;
}

.speaking-placeholder span {
    font-size: 0.8rem;
}

.speaking-card-body {
    padding: 24px;
}

.speaking-type {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 50px;
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    background: rgba(201,150,59,0.2);
    color: var(--accent-light);
    margin-bottom: 12px;
}

.speaking-card-body h3 {
    font-family: var(--font-body);
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 8px;
}

.speaking-meta {
    font-size: 0.82rem;
    color: rgba(255,255,255,0.5);
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
}

.speaking-meta svg {
    width: 14px;
    height: 14px;
}

.speaking-card-body > p:last-child {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.65);
    line-height: 1.6;
}

/* ============================================
   JUDGING / TIMELINE SECTION
   ============================================ */
.judging-timeline {
    max-width: 700px;
    margin: 0 auto;
    position: relative;
    padding-left: 40px;
}

.judging-timeline::before {
    content: '';
    position: absolute;
    left: 14px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--gray-200);
}

.timeline-item {
    position: relative;
    padding: 0 0 40px 32px;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-marker {
    position: absolute;
    left: -33px;
    top: 6px;
    width: 14px;
    height: 14px;
    border-radius: var(--radius-full);
    background: var(--accent);
    border: 3px solid var(--white);
    box-shadow: var(--shadow-sm);
}

.timeline-date {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 6px;
}

.timeline-content h3 {
    font-family: var(--font-body);
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: 6px;
}

.timeline-content p {
    font-size: 0.92rem;
    color: var(--gray-500);
    line-height: 1.6;
}

/* ============================================
   CMT (CONFERENCE MANAGEMENT) SECTION
   ============================================ */
.cmt-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 28px;
}

.cmt-card {
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 32px 28px;
    transition: var(--transition);
}

.cmt-card:hover {
    background: rgba(255,255,255,0.12);
    transform: translateY(-6px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
}

.cmt-card-header {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 18px;
}

.cmt-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    background: rgba(201,150,59,0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-light);
    flex-shrink: 0;
}

.cmt-icon svg {
    width: 22px;
    height: 22px;
}

.cmt-role-type {
    display: inline-block;
    padding: 4px 14px;
    border-radius: 50px;
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    background: rgba(201,150,59,0.2);
    color: var(--accent-light);
}

.cmt-card h3 {
    font-family: var(--font-body);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 6px;
}

.cmt-org {
    font-size: 0.88rem;
    color: rgba(255,255,255,0.5);
    margin-bottom: 12px;
}

.cmt-desc {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
    line-height: 1.7;
    margin-bottom: 16px;
}

.cmt-meta {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.cmt-meta span {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.8rem;
    color: rgba(255,255,255,0.45);
}

.cmt-meta svg {
    width: 14px;
    height: 14px;
    color: var(--accent-light);
}

/* ============================================
   AWARDS SECTION
   ============================================ */
.awards-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.award-card {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: var(--radius-md);
    padding: 36px 28px;
    text-align: center;
    transition: var(--transition);
}

.award-card:hover {
    background: rgba(255,255,255,0.1);
    transform: translateY(-6px);
}

.award-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-full);
    background: rgba(201,150,59,0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: var(--accent-light);
}

.award-icon svg {
    width: 28px;
    height: 28px;
}

.award-card h3 {
    font-family: var(--font-body);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 8px;
}

.award-org {
    font-size: 0.88rem;
    color: rgba(255,255,255,0.5);
    margin-bottom: 4px;
}

.award-year {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--accent-light);
    margin-bottom: 12px;
}

.award-desc {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
    line-height: 1.6;
}

/* ============================================
   CERTIFICATES SECTION
   ============================================ */
.cert-filters {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.cert-filter {
    padding: 8px 22px;
    border: 1.5px solid var(--gray-200);
    border-radius: 50px;
    font-family: var(--font-body);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--gray-500);
    background: transparent;
    cursor: pointer;
    transition: var(--transition);
}

.cert-filter:hover,
.cert-filter.active {
    background: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

.certificates-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.cert-card {
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--gray-100);
    background: var(--white);
    transition: var(--transition);
}

.cert-card.hidden {
    display: none;
}

.cert-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.cert-card-image {
    position: relative;
    height: 220px;
    overflow: hidden;
    background: var(--gray-50);
}

.cert-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.cert-card:hover .cert-card-image img {
    transform: scale(1.05);
}

.cert-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #f0f4f8, #e2e8f0);
    color: var(--primary);
    gap: 8px;
}

.cert-placeholder svg {
    width: 56px;
    height: 56px;
    opacity: 0.6;
}

.cert-overlay {
    position: absolute;
    inset: 0;
    background: rgba(26,54,93,0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
}

.cert-card:hover .cert-overlay {
    opacity: 1;
}

.cert-view-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 24px;
    background: var(--white);
    color: var(--primary);
    border: none;
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.cert-view-btn:hover {
    background: var(--accent);
    color: var(--white);
}

.cert-view-btn svg {
    width: 16px;
    height: 16px;
}

.cert-card-body {
    padding: 20px 24px;
}

.cert-card-body h3 {
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-800);
    margin-bottom: 6px;
}

.cert-issuer {
    font-size: 0.85rem;
    color: var(--gray-500);
    margin-bottom: 6px;
}

.cert-date {
    font-size: 0.8rem;
    color: var(--gray-400);
    display: flex;
    align-items: center;
    gap: 6px;
}

.cert-date svg {
    width: 14px;
    height: 14px;
}

/* ============================================
   MENTORING SECTION
   ============================================ */
.mentoring-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.mentoring-card {
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 36px 28px;
    transition: var(--transition);
}

.mentoring-card:hover {
    background: rgba(255,255,255,0.12);
    transform: translateY(-6px);
}

.mentoring-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-sm);
    background: rgba(201,150,59,0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: var(--accent-light);
}

.mentoring-icon svg {
    width: 26px;
    height: 26px;
}

.mentoring-card h3 {
    font-family: var(--font-body);
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 10px;
}

.mentoring-card p {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.6);
    line-height: 1.7;
    margin-bottom: 16px;
}

.mentoring-period {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-light);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* ============================================
   WRITING SECTION
   ============================================ */
.writing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.writing-card {
    border: 1px solid var(--gray-100);
    border-radius: var(--radius-md);
    padding: 28px;
    transition: var(--transition);
    background: var(--white);
}

.writing-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent);
}

.writing-card-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.writing-platform {
    padding: 4px 12px;
    border-radius: 50px;
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    background: var(--gray-100);
    color: var(--gray-600);
}

.writing-date {
    font-size: 0.8rem;
    color: var(--gray-400);
}

.writing-card h3 {
    font-family: var(--font-body);
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.writing-card h3 a {
    color: var(--gray-800);
}

.writing-card h3 a:hover {
    color: var(--accent);
}

.writing-card > p {
    font-size: 0.9rem;
    color: var(--gray-500);
    line-height: 1.7;
    margin-bottom: 16px;
}

.writing-read-more {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--primary);
}

.writing-read-more svg {
    width: 16px;
    height: 16px;
    transition: var(--transition);
}

.writing-read-more:hover svg {
    transform: translateX(4px);
}

/* ============================================
   CONTACT SECTION
   ============================================ */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 60px;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.contact-item > svg,
.contact-item > i {
    width: 24px;
    height: 24px;
    color: var(--accent-light);
    flex-shrink: 0;
    margin-top: 4px;
}

.contact-item h4 {
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 4px;
}

.contact-item a,
.contact-item p {
    font-size: 0.92rem;
    color: rgba(255,255,255,0.6);
}

.contact-item a:hover {
    color: var(--accent-light);
}

.contact-social {
    display: flex;
    gap: 12px;
    margin-top: 12px;
}

.contact-form {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: 36px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 500;
    color: rgba(255,255,255,0.8);
    margin-bottom: 8px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1.5px solid rgba(255,255,255,0.15);
    border-radius: var(--radius-sm);
    font-family: var(--font-body);
    font-size: 0.92rem;
    color: var(--white);
    background: rgba(255,255,255,0.05);
    transition: var(--transition);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: rgba(255,255,255,0.3);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    background: rgba(255,255,255,0.08);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    background: var(--gray-900);
    border-top: 1px solid rgba(255,255,255,0.05);
    padding: 40px 0;
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 24px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--white);
}

.footer-brand p {
    font-size: 0.82rem;
    color: var(--gray-500);
}

.footer-links {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.footer-links a {
    font-size: 0.85rem;
    color: var(--gray-400);
}

.footer-links a:hover {
    color: var(--accent-light);
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    color: var(--gray-500);
    transition: var(--transition);
}

.footer-social a:hover {
    color: var(--accent-light);
}

.footer-social svg {
    width: 18px;
    height: 18px;
}

/* ============================================
   LIGHTBOX
   ============================================ */
.lightbox {
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0,0,0,0.92);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.lightbox.active {
    opacity: 1;
    visibility: visible;
}

.lightbox-close {
    position: absolute;
    top: 24px;
    right: 24px;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    background: rgba(255,255,255,0.1);
    border: none;
    color: var(--white);
    font-size: 1.8rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.lightbox-close:hover {
    background: rgba(255,255,255,0.2);
}

.lightbox-content {
    max-width: 90%;
    max-height: 90vh;
    text-align: center;
}

.lightbox-content img {
    max-width: 100%;
    max-height: 80vh;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-xl);
}

.lightbox-title {
    color: var(--white);
    font-size: 1rem;
    margin-top: 16px;
    font-weight: 500;
}

/* ============================================
   BACK TO TOP
   ============================================ */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    background: var(--primary);
    color: var(--white);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    box-shadow: var(--shadow-md);
    z-index: 100;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--accent);
    transform: translateY(-3px);
}

.back-to-top svg {
    width: 20px;
    height: 20px;
}

/* ============================================
   SCROLL ANIMATIONS
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 1024px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-description {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-social {
        justify-content: center;
    }

    .hero-image {
        order: -1;
    }

    .hero-image-frame {
        width: 260px;
        height: 260px;
    }

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

    .expertise-grid,
    .speaking-grid,
    .awards-grid,
    .mentoring-grid,
    .writing-grid,
    .certificates-grid,
    .cmt-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--primary-dark);
        flex-direction: column;
        padding: 80px 32px 32px;
        gap: 4px;
        transition: var(--transition);
        box-shadow: var(--shadow-xl);
    }

    .nav-menu.active {
        right: 0;
    }

    .nav-link {
        color: rgba(255,255,255,0.8);
        padding: 12px 16px;
        width: 100%;
    }

    .navbar.scrolled .nav-link {
        color: rgba(255,255,255,0.8);
    }

    .hero-name {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .expertise-grid,
    .speaking-grid,
    .awards-grid,
    .mentoring-grid,
    .writing-grid,
    .certificates-grid,
    .cmt-grid {
        grid-template-columns: 1fr;
    }

    .publication-card {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero-name {
        font-size: 2rem;
    }

    .hero-image-frame {
        width: 200px;
        height: 200px;
    }

    .cert-filters {
        gap: 6px;
    }

    .cert-filter {
        padding: 6px 16px;
        font-size: 0.78rem;
    }

    .contact-form {
        padding: 24px;
    }
}