/* ==============================
   Dr. Manju Subberwal — Styles
   ============================== */

:root {
    --color-primary: #1a5276;
    --color-primary-dark: #0e3a56;
    --color-primary-light: #2980b9;
    --color-accent: #2ecc71;
    --color-accent-dark: #27ae60;
    --color-text: #2c3e50;
    --color-text-light: #5a6c7d;
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafb;
    --color-bg-dark: #0e2a3d;
    --color-border: #e0e6eb;
    --font-heading: 'Playfair Display', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --max-width: 1140px;
    --header-height: 72px;
    --transition: 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-height);
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-bg);
    -webkit-font-smoothing: antialiased;
}

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

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

a:hover {
    color: var(--color-primary-dark);
}

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

/* ==============================
   Header / Navigation
   ============================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--color-border);
    height: var(--header-height);
    transition: box-shadow var(--transition);
}

.site-header.scrolled {
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--color-text);
}

.logo-icon {
    flex-shrink: 0;
    display: flex;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-name {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.1rem;
    line-height: 1.2;
    color: var(--color-primary);
}

.logo-title {
    font-size: 0.75rem;
    color: var(--color-text-light);
    font-weight: 400;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 32px;
}

.main-nav a {
    color: var(--color-text);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    text-decoration: none;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-accent);
    transition: width var(--transition);
}

.main-nav a:hover::after,
.main-nav a.active::after {
    width: 100%;
}

.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(--color-text);
    transition: transform var(--transition), opacity var(--transition);
}

/* ==============================
   Hero
   ============================== */
.hero {
    position: relative;
    min-height: 600px;
    display: flex;
    align-items: center;
    padding: calc(var(--header-height) + 60px) 0 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #f0f7fb 0%, #e8f4e9 50%, #f8fafb 100%);
    z-index: 0;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: rgba(46, 204, 113, 0.06);
}

.hero-bg::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 400px;
    height: 400px;
    border-radius: 50%;
    background: rgba(26, 82, 118, 0.04);
}

.hero .container {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr 380px;
    gap: 60px;
    align-items: center;
}

.hero-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-accent-dark);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 16px;
}

.hero h1 {
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 700;
    color: var(--color-primary-dark);
    line-height: 1.15;
    margin-bottom: 12px;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--color-text-light);
    font-weight: 400;
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.05rem;
    line-height: 1.7;
    color: var(--color-text-light);
    margin-bottom: 32px;
    max-width: 540px;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    font-family: var(--font-body);
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 6px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition);
    text-decoration: none;
}

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

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

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

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

.btn-full {
    width: 100%;
}

.hero-card {
    background: #fff;
    border-radius: 16px;
    padding: 40px 32px;
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.08);
    text-align: center;
}

.hero-card-icon {
    margin-bottom: 28px;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 32px;
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-family: var(--font-heading);
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--color-primary);
}

.stat-label {
    font-size: 0.78rem;
    color: var(--color-text-light);
    font-weight: 500;
}

/* ==============================
   Sections (general)
   ============================== */
.section {
    padding: 80px 0;
}

.section:nth-child(even) {
    background: var(--color-bg-alt);
}

.section-header {
    text-align: center;
    margin-bottom: 52px;
}

.section-header h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary-dark);
    margin-bottom: 12px;
}

.section-line {
    width: 48px;
    height: 3px;
    background: var(--color-accent);
    margin: 0 auto 16px;
    border-radius: 2px;
}

.section-desc {
    font-size: 1.05rem;
    color: var(--color-text-light);
    max-width: 560px;
    margin: 0 auto;
}

/* ==============================
   About
   ============================== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: start;
}

.about-text .lead {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--color-text);
    margin-bottom: 16px;
    font-weight: 400;
}

.about-text p {
    margin-bottom: 16px;
    color: var(--color-text-light);
}

.about-details {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.detail-card {
    background: var(--color-bg-alt);
    border-radius: 10px;
    padding: 24px;
    border-left: 3px solid var(--color-accent);
}

.detail-card h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    color: var(--color-primary);
    margin-bottom: 10px;
}

.detail-card ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.detail-card li {
    font-size: 0.92rem;
    color: var(--color-text-light);
    padding-left: 16px;
    position: relative;
}

.detail-card li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 9px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--color-accent);
}

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

.expertise-card {
    background: #fff;
    border-radius: 12px;
    padding: 32px 28px;
    border: 1px solid var(--color-border);
    transition: transform var(--transition), box-shadow var(--transition);
}

.expertise-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
}

.expertise-icon {
    margin-bottom: 20px;
}

.expertise-card h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    color: var(--color-primary);
    margin-bottom: 12px;
}

.expertise-card p {
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.65;
}

/* ==============================
   Research
   ============================== */
.research-list {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.research-item {
    display: grid;
    grid-template-columns: 72px 1fr;
    gap: 24px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--color-border);
}

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

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

.research-content h3 {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    color: var(--color-primary-dark);
    margin-bottom: 6px;
    line-height: 1.4;
}

.research-journal {
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--color-primary-light);
    margin-bottom: 8px;
    font-style: italic;
}

.research-desc {
    font-size: 0.92rem;
    color: var(--color-text-light);
    line-height: 1.65;
}

.research-note {
    max-width: 800px;
    margin: 40px auto 0;
    padding: 20px 24px;
    background: var(--color-bg-alt);
    border-radius: 8px;
    border-left: 3px solid var(--color-accent);
}

.research-note p {
    font-size: 0.9rem;
    color: var(--color-text-light);
}

/* ==============================
   Department
   ============================== */
.dept-grid {
    display: grid;
    grid-template-columns: 1fr 360px;
    gap: 48px;
    align-items: start;
}

.dept-info .lead {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--color-text);
    margin-bottom: 32px;
}

.dept-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.dept-feature {
    padding: 20px;
    background: #fff;
    border-radius: 10px;
    border: 1px solid var(--color-border);
}

.dept-feature h4 {
    font-size: 0.95rem;
    color: var(--color-primary);
    margin-bottom: 8px;
    font-weight: 600;
}

.dept-feature p {
    font-size: 0.85rem;
    color: var(--color-text-light);
    line-height: 1.6;
}

.dept-team {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    border: 1px solid var(--color-border);
}

.dept-team h3 {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    color: var(--color-primary);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--color-accent);
}

.team-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.team-member {
    display: flex;
    flex-direction: column;
    padding: 12px 16px;
    border-radius: 8px;
    transition: background var(--transition);
}

.team-member:hover {
    background: var(--color-bg-alt);
}

.team-member.highlight {
    background: rgba(46, 204, 113, 0.08);
    border-left: 3px solid var(--color-accent);
}

.team-member strong {
    font-size: 0.95rem;
    color: var(--color-text);
}

.team-member span {
    font-size: 0.82rem;
    color: var(--color-text-light);
}

/* ==============================
   Contact
   ============================== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.contact-card {
    background: var(--color-bg-alt);
    border-radius: 12px;
    padding: 28px;
}

.contact-card h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    color: var(--color-primary);
    margin-bottom: 16px;
}

.contact-card address {
    font-style: normal;
    font-size: 0.95rem;
    color: var(--color-text-light);
    line-height: 1.8;
}

.contact-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.contact-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 0.93rem;
}

.contact-list li svg {
    flex-shrink: 0;
}

.contact-list a {
    color: var(--color-text);
}

.contact-list a:hover {
    color: var(--color-primary-light);
}

.contact-form-wrapper {
    background: #fff;
    border-radius: 12px;
    padding: 32px;
    border: 1px solid var(--color-border);
}

.contact-form-wrapper h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    color: var(--color-primary);
    margin-bottom: 24px;
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 6px;
}

.required {
    color: #e74c3c;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    font-family: var(--font-body);
    font-size: 0.92rem;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-bg);
    color: var(--color-text);
    transition: border-color var(--transition), box-shadow var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary-light);
    box-shadow: 0 0 0 3px rgba(41, 128, 185, 0.12);
}

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

.form-note {
    font-size: 0.8rem;
    color: var(--color-text-light);
    margin-top: 12px;
    line-height: 1.5;
}

/* ==============================
   Map
   ============================== */
.map-section {
    line-height: 0;
}

.map-section iframe {
    width: 100%;
    display: block;
}

/* ==============================
   Footer
   ============================== */
.site-footer {
    background: var(--color-bg-dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 56px 0 0;
}

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand .logo-name {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    color: #fff;
    display: block;
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 0.88rem;
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 0.9rem;
    font-weight: 600;
    color: #fff;
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-links ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-links a {
    font-size: 0.88rem;
    color: rgba(255, 255, 255, 0.6);
    transition: color var(--transition);
}

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

.footer-bottom {
    padding: 20px 0;
    text-align: center;
}

.footer-bottom p {
    font-size: 0.82rem;
    color: rgba(255, 255, 255, 0.4);
}

/* ==============================
   Back to Top
   ============================== */
.back-to-top {
    position: fixed;
    bottom: 24px;
    right: 24px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transform: translateY(12px);
    transition: all var(--transition);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 100;
}

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

.back-to-top:hover {
    background: var(--color-primary-dark);
}

/* ==============================
   Form Success/Error States
   ============================== */
.form-success {
    padding: 20px;
    background: rgba(46, 204, 113, 0.1);
    border: 1px solid rgba(46, 204, 113, 0.3);
    border-radius: 8px;
    color: var(--color-accent-dark);
    text-align: center;
    font-weight: 500;
}

.form-group.error input,
.form-group.error textarea {
    border-color: #e74c3c;
}

.form-group .error-message {
    font-size: 0.8rem;
    color: #e74c3c;
    margin-top: 4px;
}

/* ==============================
   Responsive
   ============================== */
@media (max-width: 992px) {
    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-visual {
        display: flex;
        justify-content: center;
    }

    .hero-card {
        max-width: 400px;
    }

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

    .expertise-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 64px;
    }

    .nav-toggle {
        display: flex;
    }

    .main-nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background: #fff;
        border-bottom: 1px solid var(--color-border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition);
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    }

    .main-nav.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .main-nav ul {
        flex-direction: column;
        gap: 0;
        padding: 12px 24px;
    }

    .main-nav a {
        display: block;
        padding: 12px 0;
        border-bottom: 1px solid var(--color-border);
    }

    .main-nav li:last-child a {
        border-bottom: none;
    }

    .hero {
        min-height: auto;
        padding: calc(var(--header-height) + 40px) 0 60px;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

    .section {
        padding: 60px 0;
    }

    .section-header h2 {
        font-size: 1.7rem;
    }

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

    .dept-features {
        grid-template-columns: 1fr;
    }

    .research-item {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.8rem;
    }

    .hero-desc {
        font-size: 0.95rem;
    }

    .hero-stats {
        gap: 20px;
    }

    .stat-number {
        font-size: 1.3rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .btn {
        text-align: center;
    }

    .contact-form-wrapper {
        padding: 24px 20px;
    }
}