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

:root {
    /* Color Palette */
    --color-primary: #1a1a1a;
    --color-secondary: #333333;
    --color-accent: #0066cc;
    --color-text: #2c2c2c;
    --color-text-light: #666666;
    --color-background: #ffffff;
    --color-background-alt: #f8f8f8;
    --color-border: #e0e0e0;

    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, sans-serif;
    --font-size-base: 18px;
    --font-size-small: 16px;
    --line-height-base: 1.7;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --spacing-xxl: 6rem;

    /* Layout */
    --container-max-width: 1100px;
    --border-radius: 2px;

    /* Transitions */
    --transition-speed: 0.3s;
}

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

body {
    font-family: var(--font-primary);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-text);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header and Navigation */
header {
    position: sticky;
    top: 0;
    background-color: var(--color-background);
    border-bottom: 1px solid var(--color-border);
    z-index: 1000;
    padding: var(--spacing-md) 0;
}

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

.nav-brand h1 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--color-primary);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.nav-menu a {
    color: var(--color-text);
    text-decoration: none;
    font-size: var(--font-size-small);
    transition: color var(--transition-speed);
    font-weight: 500;
}

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

/* Hero Section */
.hero {
    padding: var(--spacing-xxl) 0 var(--spacing-xl) 0;
    background-color: var(--color-background);
}

.hero-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.hero-image {
    flex-shrink: 0;
}

.hero-image img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--color-border);
}

.hero-text {
    flex: 1;
}

.hero-title {
    font-size: 3rem;
    font-weight: 300;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.5px;
}

.hero-subtitle {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--color-secondary);
    margin-bottom: var(--spacing-lg);
}

.hero-intro {
    font-size: 1.25rem;
    color: var(--color-text);
    max-width: 900px;
    line-height: 1.6;
}

/* Mission Section */
.mission {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background-alt);
}

.mission p {
    margin-bottom: var(--spacing-md);
    max-width: 900px;
}

.mission p:last-child {
    margin-bottom: 0;
}

/* Tagline Section */
.tagline {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background);
}

.tagline h2 {
    font-size: 2rem;
    font-weight: 600;
    color: var(--color-primary);
    text-align: center;
}

/* Testimonial Section */
.testimonial {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background-alt);
}

.testimonial h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.testimonial blockquote {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--color-text);
    font-style: italic;
    max-width: 900px;
    border-left: 3px solid var(--color-accent);
    padding-left: var(--spacing-md);
}

/* Values Section */
.values {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background);
}

.values h2 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.value-item h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.value-item p {
    color: var(--color-text-light);
    font-size: var(--font-size-small);
}

/* Why Section */
.why-section {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background-alt);
}

.why-section h2 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.why-section p {
    max-width: 900px;
}

/* Working Style Section */
.working-style {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background);
}

.working-style h2 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.working-style p {
    margin-bottom: var(--spacing-md);
    max-width: 900px;
}

.working-style p:last-child {
    margin-bottom: 0;
}

/* Services Section */
.services {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background-alt);
}

.services h2 {
    font-size: 2rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

/* Tabs */
.tabs {
    margin-top: var(--spacing-lg);
}

.tab-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--color-border);
    padding-bottom: var(--spacing-xs);
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.tab-button {
    background: none;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-small);
    font-family: var(--font-primary);
    color: var(--color-text-light);
    cursor: pointer;
    transition: all var(--transition-speed);
    border-bottom: 3px solid transparent;
    margin-bottom: -2px;
    font-weight: 500;
    white-space: nowrap;
}

.tab-button:hover {
    color: var(--color-accent);
    background-color: rgba(0, 102, 204, 0.05);
}

.tab-button.active {
    color: var(--color-accent);
    border-bottom-color: var(--color-accent);
    font-weight: 600;
}

.tab-button:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

.tab-content-container {
    background-color: var(--color-background);
    padding: var(--spacing-lg);
    border: 1px solid var(--color-border);
    min-height: 300px;
}

.tab-content {
    display: none;
    animation: fadeIn 0.3s ease-in;
}

.tab-content.active {
    display: block;
}

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

.tab-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.tab-content > p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.tab-content ul {
    list-style: none;
    padding-left: 0;
}

.tab-content li {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
    padding-left: var(--spacing-md);
    position: relative;
}

.tab-content li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: bold;
}

.tab-content strong {
    color: var(--color-secondary);
    font-weight: 600;
}

/* About Section */
.about {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background);
}

.about h2 {
    font-size: 2rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xl);
}

.about h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.experience-section {
    margin-bottom: var(--spacing-xxl);
}

.experience-item {
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
}

.experience-item:last-of-type {
    border-bottom: none;
}

.experience-header h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.experience-content .position {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
    line-height: 1.5;
}

.experience-content p {
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
}

.experience-content p:last-child {
    margin-bottom: 0;
}

.earlier-roles {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-lg);
    background-color: var(--color-background-alt);
    border-left: 3px solid var(--color-accent);
}

.earlier-roles p {
    color: var(--color-text-light);
    font-style: italic;
}

/* Specializations */
.specializations {
    margin-top: var(--spacing-xxl);
}

.spec-card {
    background-color: var(--color-background-alt);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    border-left: 3px solid var(--color-accent);
}

.spec-card h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.spec-card > p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.spec-list {
    margin-top: var(--spacing-lg);
}

.spec-item {
    margin-bottom: var(--spacing-lg);
}

.spec-item:last-child {
    margin-bottom: 0;
}

.spec-item h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-secondary);
    margin-bottom: var(--spacing-xs);
}

.spec-item p {
    color: var(--color-text-light);
}

/* Contact Section */
.contact {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-background-alt);
}

.contact h2 {
    font-size: 2rem;
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.contact-intro {
    font-size: 1.2rem;
    color: var(--color-text);
    margin-bottom: var(--spacing-xl);
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    max-width: 600px;
}

.contact-item h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.contact-item p {
    font-size: 1.1rem;
}

.contact-item a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-speed);
    font-weight: 500;
}

.contact-item a:hover {
    color: var(--color-primary);
    text-decoration: underline;
}

/* Footer */
footer {
    padding: var(--spacing-lg) 0;
    background-color: var(--color-primary);
    color: #ffffff;
    text-align: center;
}

footer p {
    font-size: var(--font-size-small);
    color: rgba(255, 255, 255, 0.8);
}

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --font-size-base: 16px;
        --spacing-xl: 3rem;
        --spacing-xxl: 4rem;
    }

    header .container {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .nav-menu {
        gap: var(--spacing-md);
    }

    .hero-content {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-lg);
    }

    .hero-image img {
        width: 150px;
        height: 150px;
    }

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

    .hero-subtitle {
        font-size: 1.4rem;
    }

    .hero-intro {
        font-size: 1.1rem;
    }

    .values-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .tab-buttons {
        gap: var(--spacing-xs);
        justify-content: flex-start;
    }

    .tab-button {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: 0.875rem;
    }

    .tab-content-container {
        padding: var(--spacing-md);
        min-height: 250px;
    }

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

@media (max-width: 480px) {
    .hero-image img {
        width: 120px;
        height: 120px;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .nav-menu {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }

    .tab-buttons {
        flex-direction: column;
        align-items: stretch;
        border-bottom: none;
    }

    .tab-button {
        text-align: left;
        padding: var(--spacing-sm);
        border-bottom: 1px solid var(--color-border);
        border-left: 3px solid transparent;
        margin-bottom: 0;
    }

    .tab-button.active {
        border-left-color: var(--color-accent);
        border-bottom-color: var(--color-border);
        background-color: rgba(0, 102, 204, 0.05);
    }

    .tab-content-container {
        padding: var(--spacing-sm);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* Focus styles for keyboard navigation */
a:focus,
button:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    header {
        position: static;
    }

    .nav-menu {
        display: none;
    }

    section {
        page-break-inside: avoid;
    }
}