/* ===== CSS Variables ===== */
:root {
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-bg-card: #ffffff;
    --color-text: #1e293b;
    --color-text-muted: #64748b;
    --color-text-light: #94a3b8;
    --color-primary: #3b82f6;
    --color-primary-dark: #2563eb;
    --color-secondary: #10b981;
    --color-border: #e2e8f0;
    --color-border-light: #f1f5f9;

    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;

    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-full: 9999px;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-family);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

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

/* ===== Focus States for Accessibility ===== */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

.btn:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.2);
}

.nav-link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 4px;
    border-radius: var(--radius-sm);
}

.hero-social a:focus-visible,
.contact-link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

.project-card:focus-within {
    box-shadow: var(--shadow-xl);
    transform: translateY(-5px);
}

ul {
    list-style: none;
}

/* ===== Utilities ===== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--color-text);
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -0.75rem;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    border-radius: var(--radius-full);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 500;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
}

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

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

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

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

.btn-full {
    width: 100%;
}

/* ===== Tags ===== */
.tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-primary);
    background-color: rgba(59, 130, 246, 0.1);
    border-radius: var(--radius-full);
    margin: 0.25rem;
}

/* ===== 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);
    transition: all var(--transition-normal);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 1.5rem;
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-text);
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-primary);
    transition: width var(--transition-normal);
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-primary);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    transition: all var(--transition-normal);
}

/* ===== Hero Section ===== */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 6rem 1.5rem 2rem;
    background: linear-gradient(180deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
    position: relative;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.hero-content {
    animation: fadeInUp 0.8s ease;
}

.hero-greeting {
    font-size: 1.125rem;
    color: var(--color-primary);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.hero-name {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--color-text);
    line-height: 1.1;
    margin-bottom: 0.75rem;
}

.hero-title {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 500px;
    margin-bottom: 2rem;
    line-height: 1.7;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.hero-social {
    display: flex;
    gap: 1rem;
}

.hero-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-full);
    background-color: var(--color-bg-alt);
    color: var(--color-text-muted);
    transition: all var(--transition-normal);
}

.hero-social a:hover {
    background-color: var(--color-primary);
    color: white;
    transform: translateY(-3px);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeInUp 0.8s ease 0.2s backwards;
}

.hero-photo {
    width: 350px;
    height: 350px;
    border-radius: var(--radius-lg);
    object-fit: cover;
    object-position: center top;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    border: 4px solid var(--color-border);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.hero-photo:hover {
    transform: scale(1.03);
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.4);
}

.hero-image-placeholder {
    width: 350px;
    height: 350px;
    border-radius: var(--radius-lg);
    background: linear-gradient(135deg, var(--color-bg-alt) 0%, var(--color-border) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-muted);
    font-size: 1.125rem;
    border: 2px dashed var(--color-border);
    position: relative;
    overflow: hidden;
}

.hero-image-placeholder::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(16, 185, 129, 0.1) 100%);
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-text-muted);
    font-size: 0.875rem;
    animation: bounce 2s infinite;
}

/* ===== About Section ===== */
.about {
    padding: 6rem 0;
    background-color: var(--color-bg);
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: start;
}

.about-text p {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

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

.about-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.stat-card {
    background-color: var(--color-bg-alt);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    text-align: center;
    border: 1px solid var(--color-border-light);
    transition: all var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary);
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

/* ===== Experience Section ===== */
.experience {
    padding: 6rem 0;
    background-color: var(--color-bg-alt);
}

.timeline {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(180deg, var(--color-primary), var(--color-secondary));
}

.timeline-item {
    position: relative;
    padding-left: 3rem;
    padding-bottom: 3rem;
}

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

.timeline-marker {
    position: absolute;
    left: -6px;
    top: 0;
    width: 14px;
    height: 14px;
    border-radius: var(--radius-full);
    background-color: var(--color-primary);
    border: 3px solid var(--color-bg-alt);
}

.timeline-content {
    background-color: var(--color-bg-card);
    padding: 1.75rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.timeline-content:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-lg);
}

.timeline-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.timeline-title-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.company-logo {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    object-fit: contain;
    flex-shrink: 0;
    background-color: white;
    padding: 4px;
}

.timeline-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
}

.timeline-company {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-primary);
    background-color: rgba(59, 130, 246, 0.1);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
}

.timeline-date {
    display: block;
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-bottom: 1rem;
}

.timeline-description {
    color: var(--color-text-muted);
    line-height: 1.7;
    margin-bottom: 1rem;
}

.timeline-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
}

/* ===== Skills Section ===== */
.skills {
    padding: 6rem 0;
    background-color: var(--color-bg);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.skill-category {
    background-color: var(--color-bg-alt);
    padding: 2rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: all var(--transition-normal);
}

.skill-category:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-5px);
}

.skill-category-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--color-border);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.skill-tag {
    display: inline-flex;
    align-items: center;
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    overflow: hidden;
    transition: all var(--transition-fast);
}

.skill-tag:hover {
    border-color: var(--color-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.skill-tag-name {
    padding: 0.5rem 0.75rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text);
}

.skill-tag-years {
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: white;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
}

.achievements-section {
    margin-top: 3rem;
    text-align: center;
}

.achievements-section .skill-category-title {
    display: inline-block;
    margin-bottom: 1.5rem;
}

.achievements-grid {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.achievement-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background-color: var(--color-bg-alt);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: all var(--transition-normal);
}

.achievement-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--color-primary);
}

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

.achievement-text {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text);
}

/* ===== Projects Section ===== */
.projects {
    padding: 6rem 0;
    background-color: var(--color-bg-alt);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.project-card {
    background-color: var(--color-bg-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.project-image {
    height: 200px;
    overflow: hidden;
}

.project-placeholder {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.125rem;
    font-weight: 500;
}

.project-content {
    padding: 1.5rem;
}

.project-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 0.75rem;
}

.project-description {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.project-tags {
    margin-bottom: 1rem;
}

.project-links {
    display: flex;
    gap: 1rem;
}

.project-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-primary);
    transition: all var(--transition-fast);
}

.project-link:hover {
    color: var(--color-primary-dark);
}

/* ===== Contact Section ===== */
.contact {
    padding: 6rem 0;
    background-color: var(--color-bg);
}

.contact-intro {
    text-align: center;
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 600px;
    margin: -1rem auto 3rem;
}

.contact-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 3rem;
    max-width: 900px;
    margin: 0 auto;
}

.contact-form {
    background-color: var(--color-bg-alt);
    padding: 2rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 0.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    font-family: inherit;
    color: var(--color-text);
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-light);
}

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

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.contact-card {
    background-color: var(--color-bg-alt);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
}

.contact-card h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 1rem;
}

.contact-card p {
    color: var(--color-text-muted);
}

.contact-links {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.contact-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--color-text-muted);
    font-size: 0.9rem;
    transition: all var(--transition-fast);
}

.contact-link:hover {
    color: var(--color-primary);
}

.contact-link svg {
    flex-shrink: 0;
}

/* ===== Footer ===== */
.footer {
    padding: 2rem 0;
    background-color: var(--color-bg-alt);
    border-top: 1px solid var(--color-border-light);
    text-align: center;
}

.footer p {
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

.footer-tagline {
    margin-top: 0.5rem;
    color: var(--color-text-light);
    font-size: 0.8rem;
}

/* ===== Animations ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

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

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 3rem;
    }

    .hero-content {
        order: 1;
    }

    .hero-image {
        order: 0;
    }

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

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

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

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

    .about-stats {
        grid-template-columns: repeat(4, 1fr);
    }

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

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

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background-color: var(--color-bg);
        flex-direction: column;
        justify-content: center;
        gap: 2rem;
        box-shadow: var(--shadow-xl);
        transition: right var(--transition-normal);
    }

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

    .nav-toggle {
        display: flex;
        z-index: 1001;
    }

    .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);
    }

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

    .hero-title {
        font-size: 1.25rem;
    }

    .hero-image-placeholder {
        width: 280px;
        height: 280px;
    }

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

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

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

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

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

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 280px;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 5rem 1rem 2rem;
    }

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

    .hero-description {
        font-size: 1rem;
    }

    .stat-card {
        padding: 1rem;
    }

    .stat-number {
        font-size: 1.5rem;
    }

    .timeline::before {
        left: 6px;
    }

    .timeline-item {
        padding-left: 2.5rem;
    }

    .timeline-marker {
        left: 0;
    }

    .timeline-content {
        padding: 1.25rem;
    }

    .timeline-header {
        flex-direction: column;
        align-items: flex-start;
    }
}