/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 700;
    color: #667eea;
}

.nav-logo i {
    margin-right: 10px;
    font-size: 1.8rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 15px;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    background: #667eea;
    color: white;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Main Content */
.main-content {
    margin-top: 70px;
    min-height: calc(100vh - 70px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.9), rgba(118, 75, 162, 0.9));
    color: white;
    text-align: center;
    padding: 100px 0;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-content p {
    font-size: 1.3rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Selection Section */
.selection-section {
    padding: 60px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.selection-container {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.selection-container h2 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    font-weight: 300;
}

.isotope-selector {
    margin-top: 30px;
}

.isotope-selector select {
    width: 100%;
    max-width: 400px;
    padding: 15px 20px;
    font-size: 1.1rem;
    border: none;
    border-radius: 50px;
    background: white;
    color: #333;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    cursor: pointer;
    transition: all 0.3s ease;
}

.isotope-selector select:focus {
    outline: none;
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
    transform: translateY(-2px);
}

/* Isotope Details Section */
.isotope-details-section {
    padding: 80px 0;
    background: #f8f9fa;
}

.isotope-details {
    max-width: 1000px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.isotope-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px;
    text-align: center;
}

/* Isotope icon container */
.isotope-icon-container {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 15px;
}

/* Isotope icon styling */
.isotope-icon {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    background: rgba(255, 255, 255, 0.1);
    padding: 8px;
}

.isotope-name {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.isotope-content {
    padding: 40px;
}

/* Responsive isotope info grid */
.isotope-info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.info-card {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 12px;
    border-left: 4px solid #667eea;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.info-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
}

.info-card h4 {
    font-size: 0.9rem;
    color: #666;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
    font-weight: 500;
}

.info-card p {
    font-size: 1.1rem;
    font-weight: 600;
    color: #333;
    margin: 0;
}

.isotope-icon:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

/* Fallback symbol styling */
.isotope-symbol-fallback {
    font-size: 2.5rem;
    font-weight: bold;
    color: #fff;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.isotope-symbol {
    font-size: 4rem;
    font-weight: bold;
    margin-bottom: 10px;
}

.isotope-name {
    font-size: 1.8rem;
    margin-bottom: 5px;
    font-weight: 300;
}

.isotope-generic {
    font-size: 1.1rem;
    opacity: 0.9;
}



/* Generic drugs section */
.generic-drugs-section {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
    padding: 25px;
    border-radius: 15px;
    margin-bottom: 20px;
}

.generic-drugs-section h4 {
    color: white;
    margin-bottom: 15px;
    font-size: 1.2rem;
    font-weight: 600;
}

.generic-drugs-section p {
    color: white;
    opacity: 0.95;
    line-height: 1.6;
    font-size: 1.05rem;
    margin: 0;
}

.medical-uses-section {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    color: white;
    padding: 30px;
    border-radius: 15px;
    margin-top: 30px;
}

.medical-uses-section h4 {
    color: white;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.medical-uses-section p {
    color: white;
    opacity: 0.95;
    line-height: 1.7;
    font-size: 1.05rem;
}

/* Clinical uses list styling */
.clinical-uses-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.clinical-uses-list li {
    color: white;
    opacity: 0.95;
    line-height: 1.7;
    font-size: 1.05rem;
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.clinical-uses-list li:before {
    content: "•";
    color: white;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Isotopes Section */
.isotopes-section {
    padding: 60px 0;
}

.isotopes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.isotope-card {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.isotope-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.isotope-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.isotope-header {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
}

.isotope-icon {
    width: 60px;
    height: 60px;
    margin-right: 20px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
}

.isotope-title h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #333;
    margin-bottom: 5px;
}

.isotope-title p {
    color: #666;
    font-size: 0.9rem;
}

.isotope-info {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 20px;
}

.info-item {
    display: flex;
    flex-direction: column;
}

.info-label {
    font-size: 0.8rem;
    color: #999;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 5px;
}

.info-value {
    font-weight: 600;
    color: #333;
}

.isotope-badges {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.badge {
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-pet {
    background: #e3f2fd;
    color: #1976d2;
}

.badge-spect {
    background: #f3e5f5;
    color: #7b1fa2;
}

.badge-planar {
    background: #e8f5e8;
    color: #388e3c;
}

.badge-diagnostic {
    background: #fff3e0;
    color: #f57c00;
}

.badge-therapeutic {
    background: #ffebee;
    color: #d32f2f;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: white;
    margin: 5% auto;
    padding: 40px;
    border-radius: 15px;
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.close {
    position: absolute;
    right: 20px;
    top: 20px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    color: #999;
    transition: color 0.3s ease;
}

.close:hover {
    color: #333;
}

/* Footer */
.footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 30px 0;
    margin-top: auto;
}

/* Page Specific Styles */
.page-header {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.9), rgba(118, 75, 162, 0.9));
    color: white;
    text-align: center;
    padding: 80px 0 60px;
}

.page-header h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.page-content {
    background: white;
    padding: 60px 0;
    min-height: 60vh;
}

.content-section {
    margin-bottom: 50px;
}

.content-section h2 {
    font-size: 2rem;
    color: #333;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 3px solid #667eea;
}

.content-section h3 {
    font-size: 1.5rem;
    color: #555;
    margin: 30px 0 15px;
}

.content-section p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #666;
    margin-bottom: 20px;
}

.content-section ul {
    margin: 20px 0;
    padding-left: 30px;
}

.content-section li {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 10px;
}

/* Contact Form */
.contact-form {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #333;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

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

.btn {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    padding: 15px 30px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

/* Responsive Design - Mobile First Approach */

/* Extra Small Devices (phones, 320px and up) */
@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .nav-container {
        padding: 0 15px;
        height: 60px;
    }

    .nav-logo {
        font-size: 1.2rem;
    }

    .nav-logo i {
        font-size: 1.4rem;
    }

    .main-content {
        margin-top: 60px;
    }

    .hero {
        padding: 60px 0;
    }

    .hero-content h1 {
        font-size: 2rem;
        line-height: 1.2;
        margin-bottom: 15px;
    }

    .hero-content p {
        font-size: 1rem;
        padding: 0 10px;
    }

    .selection-section {
        padding: 40px 0;
    }

    .selection-container h2 {
        font-size: 1.8rem;
        margin-bottom: 20px;
    }

    .isotope-selector select {
        padding: 12px 15px;
        font-size: 1rem;
        max-width: 100%;
    }

    .isotope-details-section {
        padding: 40px 0;
    }

    .isotope-header {
        padding: 30px 20px;
    }

    .isotope-icon {
        width: 60px;
        height: 60px;
    }

    .isotope-header h2 {
        font-size: 1.8rem;
    }

    .isotope-content {
        padding: 20px;
    }

    .isotope-info {
        grid-template-columns: 1fr;
        gap: 10px;
    }

    .page-header {
        padding: 60px 0 40px;
    }

    .page-header h1 {
        font-size: 2rem;
    }

    .page-content {
        padding: 40px 0;
    }

    .content-section h2 {
        font-size: 1.5rem;
    }

    .content-section h3 {
        font-size: 1.3rem;
    }

    .content-section p,
    .content-section li {
        font-size: 1rem;
    }

    .contact-form {
        padding: 25px 15px;
        margin: 0 15px;
    }

    .modal-content {
        margin: 15% auto;
        padding: 20px 15px;
        width: 95%;
        max-height: 70vh;
    }

    .generic-drugs-section,
    .clinical-uses-section {
        padding: 15px;
        margin: 15px 0;
    }

    .clinical-uses-list li {
        font-size: 0.9rem;
        margin-bottom: 8px;
    }
}

/* Small Devices (landscape phones, 481px to 768px) */
@media (min-width: 481px) and (max-width: 768px) {
    .hero-content h1 {
        font-size: 2.5rem;
    }

    .hero-content p {
        font-size: 1.2rem;
    }

    .selection-container h2 {
        font-size: 2.2rem;
    }

    .isotope-header {
        padding: 35px 25px;
    }

    .isotope-icon {
        width: 70px;
        height: 70px;
    }

    .isotope-content {
        padding: 25px;
    }

    .page-header h1 {
        font-size: 2.5rem;
    }

    .contact-form {
        padding: 35px 25px;
    }

    .modal-content {
        margin: 10% auto;
        padding: 30px 20px;
        width: 90%;
    }
}

/* Medium Devices (tablets, 769px to 1024px) */
@media (min-width: 769px) and (max-width: 1024px) {
    .container {
        padding: 0 30px;
    }

    .hero-content h1 {
        font-size: 3rem;
    }

    .isotope-details {
        max-width: 900px;
    }

    .isotope-info {
        grid-template-columns: 1fr 1fr;
        gap: 20px;
    }
}

/* Mobile Navigation for tablets and phones */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 60px;
        flex-direction: column;
        background-color: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(10px);
        width: 100%;
        text-align: center;
        transition: left 0.3s ease;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.1);
        padding: 20px 0;
        z-index: 999;
    }

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

    .nav-menu li {
        margin: 15px 0;
    }

    .nav-link {
        padding: 15px 20px;
        font-size: 1.1rem;
        justify-content: center;
    }

    .search-container {
        flex-direction: column;
        align-items: stretch;
    }

    .search-box {
        max-width: none;
    }

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

/* Large Devices (desktops, 1025px to 1200px) */
@media (min-width: 1025px) and (max-width: 1200px) {
    .container {
        max-width: 1000px;
    }

    .isotope-details {
        max-width: 950px;
    }
}

/* Extra Large Devices (large desktops, 1201px and up) */
@media (min-width: 1201px) {
    .container {
        max-width: 1200px;
    }

    .hero-content h1 {
        font-size: 4rem;
    }

    .hero-content p {
        font-size: 1.4rem;
    }

    .selection-container h2 {
        font-size: 3rem;
    }

    .isotope-details {
        max-width: 1100px;
    }
}

/* Touch-friendly improvements */
@media (hover: none) and (pointer: coarse) {
    .nav-link,
    .btn,
    .isotope-selector select {
        min-height: 44px;
        padding: 12px 20px;
    }

    .close {
        font-size: 32px;
        padding: 10px;
    }
}

/* High DPI displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .isotope-icon {
        image-rendering: -webkit-optimize-contrast;
        image-rendering: crisp-edges;
    }
}