/* ===========================
   CSS Variables & Reset
   =========================== */
:root {
    /* Colors - Professional, understated palette */
    --color-bg: #fafafa;
    --color-bg-alt: #ffffff;
    --color-text: #1a1a1a;
    --color-text-secondary: #5a5a5a;
    --color-text-muted: #888888;
    --color-accent: #2c5282;
    --color-accent-light: #4a7ab8;
    --color-border: #e5e5e5;
    --color-border-light: #f0f0f0;
    --color-huawei: #e4002b;

    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.25s ease;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;

    /* Container */
    --container-max: 1100px;
    --container-padding: 1.5rem;
}

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

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

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

a {
    color: inherit;
    text-decoration: none;
}

ul {
    list-style: none;
}

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

/* ===========================
   Layout
   =========================== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.section-title {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xl);
    color: var(--color-text);
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -0.5rem;
    left: 0;
    width: 3rem;
    height: 2px;
    background-color: var(--color-accent);
}

/* ===========================
   Navigation
   =========================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border-light);
    padding: var(--spacing-sm) 0;
}

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

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
}

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

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    transition: var(--transition-fast);
}

/* ===========================
   Hero Section
   =========================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    padding-bottom: var(--spacing-2xl);
    background-color: var(--color-bg-alt);
}

.hero-wrapper {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: var(--spacing-2xl);
    align-items: center;
}

.hero-content {
    max-width: 600px;
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-photo {
    width: 280px;
    height: 280px;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid var(--color-border-light);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.greeting {
    font-size: 1rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-xs);
    font-weight: 400;
}

.name {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
    letter-spacing: -1px;
}

.title {
    font-size: clamp(1.25rem, 3vw, 1.5rem);
    font-weight: 500;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xs);
}

.tagline {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* Hero Metrics */
.hero-metrics {
    display: flex;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md) 0;
    border-top: 1px solid var(--color-border-light);
    border-bottom: 1px solid var(--color-border-light);
}

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

.metric-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-accent);
}

.metric-label {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Hero Skills */
.hero-skills {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-xl);
}

.skill-tag {
    display: inline-block;
    padding: 0.4rem 0.8rem;
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 100px;
    font-size: 0.85rem;
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}

.skill-tag:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.hero-actions {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all var(--transition-base);
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background-color: var(--color-accent-light);
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

/* ===========================
   About Section
   =========================== */
.about {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: start;
}

.about-text p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-secondary);
    font-size: 1.05rem;
}

.about-text strong {
    color: var(--color-text);
    font-weight: 600;
}

/* About Highlights */
.about-highlights {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.highlight-card {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background-color: var(--color-bg-alt);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
}

.highlight-icon {
    font-size: 1.5rem;
}

.highlight-content h3 {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 2px;
}

.highlight-content p {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
}

.highlight-company {
    font-size: 0.85rem;
    color: var(--color-accent);
    font-weight: 500;
}

/* ===========================
   Experience Section
   =========================== */
.experience {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg-alt);
}

.timeline {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2xl);
}

.timeline-company {
    background-color: var(--color-bg);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid var(--color-border-light);
}

.company-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--color-border-light);
}

.company-logo {
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #e4002b 0%, #c00025 100%);
    color: white;
    font-size: 0.7rem;
    font-weight: 700;
    border-radius: var(--radius-md);
    letter-spacing: 0.5px;
}

.company-logo.gov {
    background: linear-gradient(135deg, #2c5282 0%, #1a365d 100%);
}

.company-info h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 2px;
}

.company-tenure {
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

.timeline-roles {
    position: relative;
    padding-left: var(--spacing-xl);
}

.timeline-roles::before {
    content: '';
    position: absolute;
    left: 6px;
    top: 0;
    bottom: 0;
    width: 2px;
    background-color: var(--color-border);
}

.timeline-item {
    position: relative;
    padding-bottom: var(--spacing-lg);
}

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

.timeline-marker {
    position: absolute;
    left: calc(-1 * var(--spacing-xl) + 2px);
    top: 4px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--color-accent);
    border: 2px solid var(--color-bg);
}

.timeline-content h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.timeline-content .period {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-sm);
}

.timeline-content .description {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

.responsibilities {
    list-style: disc;
    margin-left: var(--spacing-md);
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

.responsibilities li {
    margin-bottom: var(--spacing-xs);
    line-height: 1.5;
}

.responsibilities strong {
    color: var(--color-text);
}

.skill-tags-small {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-sm);
}

.skill-tags-small span {
    padding: 0.25rem 0.6rem;
    background-color: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

/* ===========================
   Education Section
   =========================== */
.education {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg);
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.education-card {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background-color: var(--color-bg-alt);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
}

.edu-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.edu-content h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.degree {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-xs);
}

.edu-period {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-xs);
}

.edu-location {
    display: inline-block;
    padding: 0.2rem 0.5rem;
    background-color: var(--color-bg);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

/* ===========================
   Certifications Section
   =========================== */
.certifications {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg-alt);
}

.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.cert-category {
    background-color: var(--color-bg);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid var(--color-border-light);
}

.cert-category-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 1px solid var(--color-border-light);
}

.cert-icon {
    font-size: 1.25rem;
}

.cert-list li {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--color-border-light);
    gap: var(--spacing-sm);
}

.cert-list li:last-child {
    border-bottom: none;
}

.cert-info {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.cert-name {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
}

.cert-date {
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

.cert-badge {
    font-size: 0.65rem;
    font-weight: 600;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    background-color: var(--color-border-light);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    white-space: nowrap;
    flex-shrink: 0;
}

.cert-badge.verified {
    background-color: #e6f4ea;
    color: #1e7e34;
}

.cert-badge.expert {
    background-color: #fef3c7;
    color: #b45309;
}

.cert-badge.professional {
    background-color: #dbeafe;
    color: #1d4ed8;
}

/* ===========================
   Languages Section
   =========================== */
.languages {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg);
}

.languages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.language-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--spacing-lg);
    background-color: var(--color-bg-alt);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    text-align: center;
}

.language-flag {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
}

.language-name {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.language-level {
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

/* ===========================
   Contact Section
   =========================== */
.contact {
    padding: var(--spacing-3xl) 0;
    background-color: var(--color-bg-alt);
}

.contact-intro {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin-bottom: var(--spacing-xl);
}

.contact-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    max-width: 400px;
}

.contact-card {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background-color: var(--color-bg);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: all var(--transition-base);
}

.contact-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-2px);
}

.contact-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-accent);
    color: white;
    border-radius: var(--radius-md);
}

.contact-text {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.contact-label {
    font-weight: 600;
    color: var(--color-text);
}

.contact-value {
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

/* ===========================
   Footer
   =========================== */
.footer {
    padding: var(--spacing-lg) 0;
    background-color: var(--color-bg);
    border-top: 1px solid var(--color-border-light);
    text-align: center;
}

.footer p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

/* ===========================
   Responsive Design
   =========================== */
@media (max-width: 900px) {
    .about-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--color-bg-alt);
        flex-direction: column;
        padding: var(--spacing-md);
        border-bottom: 1px solid var(--color-border-light);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero {
        padding-top: 100px;
        min-height: auto;
        padding-bottom: var(--spacing-xl);
    }

    .hero-wrapper {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-image {
        order: -1;
        margin-bottom: var(--spacing-md);
    }

    .profile-photo {
        width: 150px;
        height: 150px;
    }

    .hero-content {
        max-width: 100%;
    }

    .name {
        font-size: 1.75rem;
    }

    .title {
        font-size: 1rem;
    }

    .tagline {
        font-size: 0.95rem;
    }

    .hero-metrics {
        flex-direction: column;
        gap: var(--spacing-sm);
        align-items: center;
    }

    .metric {
        flex-direction: row;
        align-items: center;
        gap: var(--spacing-sm);
    }

    .metric-value {
        font-size: 1.1rem;
        min-width: 50px;
    }

    .metric-label {
        font-size: 0.75rem;
    }

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

    .skill-tag {
        font-size: 0.75rem;
        padding: 0.3rem 0.6rem;
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
    }

    .btn {
        width: 100%;
    }

    .company-header {
        flex-direction: column;
        text-align: center;
    }

    .timeline-roles {
        padding-left: var(--spacing-md);
    }

    .timeline-marker {
        left: calc(-1 * var(--spacing-md) + 2px);
    }

    .responsibilities {
        font-size: 0.85rem;
        margin-left: var(--spacing-sm);
    }

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

    .education-card {
        flex-direction: column;
        text-align: center;
    }

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

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

    .contact-links {
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    :root {
        --container-padding: 1rem;
        --spacing-lg: 1.5rem;
        --spacing-xl: 2rem;
        --spacing-2xl: 2.5rem;
        --spacing-3xl: 3rem;
    }

    .name {
        font-size: 1.5rem;
        letter-spacing: -0.5px;
    }

    .title {
        font-size: 0.9rem;
    }

    .profile-photo {
        width: 120px;
        height: 120px;
    }

    .section-title {
        font-size: 1.4rem;
    }

    .timeline-company {
        padding: var(--spacing-md);
    }

    .company-logo {
        width: 50px;
        height: 50px;
        font-size: 0.6rem;
    }

    .timeline-content h4 {
        font-size: 1rem;
    }

    .cert-category {
        padding: var(--spacing-md);
    }

    .cert-name {
        font-size: 0.8rem;
    }

    .about-text p {
        font-size: 0.95rem;
    }
}

/* ===========================
   Animations
   =========================== */
@media (prefers-reduced-motion: no-preference) {

    .hero-content,
    .about-content,
    .timeline-company,
    .education-card,
    .cert-category,
    .language-card {
        animation: fadeInUp 0.6s ease-out both;
    }

    .hero-content {
        animation-delay: 0.1s;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}