/* CSS Variables for Theme */
:root {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #252525;
    --bg-card: rgba(255, 255, 255, 0.03);
    --bg-navbar: rgba(15, 15, 15, 0.8);
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-tertiary: #707070;
    --border-color: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(255, 255, 255, 0.15);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.7);
    --accent-primary: #3b82f6;
    --accent-hover: #60a5fa;
    --transition-speed: 0.2s;
    --transition-smooth: cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius-sm: 6px;
    --border-radius-md: 12px;
    --border-radius-lg: 16px;
    --max-width: 1100px;
}

/* Light Theme */
[data-theme="light"] {
    --bg-primary: #fafafa;
    --bg-secondary: #f5f5f5;
    --bg-tertiary: #e5e5e5;
    --bg-card: rgba(255, 255, 255, 0.8);
    --bg-navbar: rgba(250, 250, 250, 0.8);
    --text-primary: #0f0f0f;
    --text-secondary: #525252;
    --text-tertiary: #737373;
    --border-color: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(0, 0, 0, 0.15);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.08);
    --accent-primary: #2563eb;
    --accent-hover: #3b82f6;
}

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

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    overflow-x: hidden;
    transition: background-color var(--transition-speed) var(--transition-smooth),
                color var(--transition-speed) var(--transition-smooth);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2.25rem;
    margin-bottom: 3rem;
    font-weight: 600;
}

h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

p {
    font-size: 1.0625rem;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* Scroll Progress Bar */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 2px;
    background: var(--accent-primary);
    width: 0%;
    z-index: 1001;
    transition: width 0.1s ease;
}

.navbar {
    position: fixed;
    top: 2px;
    width: 100%;
    background-color: var(--bg-navbar);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 16px 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
    transition: all var(--transition-speed) var(--transition-smooth);
}

.navbar-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.navbar-menu {
    list-style: none;
    display: flex;
    gap: 28px;
    margin: 0;
    padding: 0;
}

.navbar-menu li {
    display: inline;
}

.navbar-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    transition: color var(--transition-speed) var(--transition-smooth);
}

.navbar-menu a:hover {
    color: var(--text-primary);
}

/* Theme Toggle Button */
.theme-toggle {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    margin-right: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius-sm);
    transition: all var(--transition-speed) var(--transition-smooth);
    width: 36px;
    height: 36px;
}

.theme-toggle:hover {
    background-color: var(--bg-card);
}

.theme-toggle svg {
    stroke: var(--text-secondary);
    transition: stroke var(--transition-speed) var(--transition-smooth);
}

.theme-toggle:hover svg {
    stroke: var(--text-primary);
}

.sun-icon {
    display: block;
}

.moon-icon {
    display: none;
}

[data-theme="light"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon {
    display: block;
}

.hamburger {
    display: none;
    cursor: pointer;
    margin-left: auto;
    background: transparent;
    border: none;
    padding: 8px;
    width: 36px;
    height: 36px;
}

.hamburger:hover {
    background: var(--bg-card);
    border-radius: var(--border-radius-sm);
}

.hamburger-line {
    display: block;
    width: 20px;
    height: 2px;
    margin: 4px auto;
    background: var(--text-secondary);
    transition: all var(--transition-speed) var(--transition-smooth);
}

.hamburger:hover .hamburger-line {
    background: var(--text-primary);
}

/* Hero Section */
.hero {
    padding: 140px 0 80px;
}

.hero-content {
    max-width: 720px;
}

.hero-greeting {
    font-size: 1rem;
    color: var(--text-tertiary);
    margin-bottom: 1rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    letter-spacing: -0.03em;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    line-height: 1.6;
    max-width: 600px;
}

.hero-cta {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.btn-primary, .btn-secondary {
    padding: 12px 24px;
    border-radius: var(--border-radius-sm);
    font-size: 0.9375rem;
    font-weight: 500;
    text-decoration: none;
    transition: all var(--transition-speed) var(--transition-smooth);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-primary {
    background: var(--accent-primary);
    color: white;
    border: none;
}

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

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

.btn-secondary:hover {
    border-color: var(--border-hover);
    background: var(--bg-card);
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-speed) var(--transition-smooth);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    border-color: var(--border-hover);
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

.back-to-top svg {
    stroke: var(--text-secondary);
    transition: stroke var(--transition-speed) var(--transition-smooth);
}

.back-to-top:hover svg {
    stroke: var(--text-primary);
}

/* Visitor Counter */
.visitor-counter {
    display: inline-block;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 8px 16px;
    border-radius: var(--border-radius-sm);
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

#visitor-count {
    font-weight: 600;
    color: var(--accent-primary);
}

/* Sections */
section {
    padding: 60px 0;
}

/* About Section */
.about {
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.4s var(--transition-smooth),
                transform 0.4s var(--transition-smooth);
}

.about.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.about p {
    max-width: 720px;
    margin-bottom: 1.25rem;
}

/* Projects Section */
.projects {
    padding: 60px 0;
}

.projects-timeline {
    position: relative;
    padding-left: 40px;
}

.projects-timeline::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border-color);
}

.project {
    position: relative;
    margin-bottom: 40px;
    opacity: 0;
    transform: translateY(10px);
    transition: all 0.4s var(--transition-smooth);
}

.project::before {
    content: '';
    position: absolute;
    left: -39px;
    top: 8px;
    width: 10px;
    height: 10px;
    background: var(--accent-primary);
    border-radius: 50%;
    border: 3px solid var(--bg-primary);
}

.project.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.project-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 12px;
}

.project-title {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
}

.project h3 {
    font-size: 1.25rem;
    margin: 0;
    font-weight: 600;
}

.project-status {
    display: inline-flex;
    align-items: center;
    padding: 4px 12px;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 500;
    white-space: nowrap;
}

.project-status.active {
    background: rgba(59, 130, 246, 0.1);
    color: var(--accent-primary);
    border: 1px solid rgba(59, 130, 246, 0.2);
}

.project-status.completed {
    background: rgba(34, 197, 94, 0.1);
    color: #22c55e;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.project-description {
    margin-bottom: 16px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.project-features {
    margin: 16px 0;
}

.project-features h4 {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.project-features ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 8px;
}

.project-features li {
    color: var(--text-secondary);
    padding-left: 20px;
    position: relative;
    line-height: 1.6;
    font-size: 0.9375rem;
}

.project-features li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 9px;
    width: 4px;
    height: 4px;
    background: var(--text-tertiary);
    border-radius: 50%;
}

.project-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
}

.project-link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9375rem;
    transition: color var(--transition-speed) var(--transition-smooth);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

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

.project-link::after {
    content: '→';
    transition: transform var(--transition-speed) var(--transition-smooth);
}

.project-link:hover::after {
    transform: translateX(4px);
}

/* Projects in Progress Section */
.projects-in-progress {
    padding: 60px 0;
}

/* Skills Section */
.skills {
    padding: 60px 0;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.4s var(--transition-smooth),
                transform 0.4s var(--transition-smooth);
}

.skills.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.skills h2 {
    margin-bottom: 2rem;
}

.skills-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.skill-item {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 100px;
    padding: 10px 20px 10px 10px;
    transition: all var(--transition-speed) var(--transition-smooth);
}

.skill-item:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
}

.skill-item img {
    width: 32px;
    height: 32px;
    object-fit: contain;
    flex-shrink: 0;
}

.skill-item p {
    margin: 0;
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    white-space: nowrap;
}

.skill-item:hover p {
    color: var(--text-primary);
}

/* Certifications Section */
.certifications {
    padding: 60px 0;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.4s var(--transition-smooth),
                transform 0.4s var(--transition-smooth);
}

.certifications.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.certifications ul {
    list-style: none;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 16px;
}

.certifications li {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    padding: 24px;
    transition: all var(--transition-speed) var(--transition-smooth);
    position: relative;
}

.certifications li::before {
    content: '✓';
    position: absolute;
    top: 24px;
    left: 24px;
    width: 32px;
    height: 32px;
    background: var(--accent-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.125rem;
}

.certifications li:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
}

.certifications li p {
    margin: 0;
    padding-left: 48px;
}

.certifications li p strong:first-child {
    display: block;
    font-size: 1.125rem;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.certifications li p strong:last-of-type {
    color: var(--text-secondary);
    font-weight: 500;
}

/* Contacts Section */
.contacts {
    padding: 60px 0;
}

.contacts h2 {
    margin-bottom: 2rem;
}

.contacts-grid {
    display: grid;
    gap: 16px;
    max-width: 600px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    transition: all var(--transition-speed) var(--transition-smooth);
    position: relative;
}

.contact-item:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
}

.contact-link {
    text-decoration: none;
    cursor: pointer;
}

.contact-link:hover .contact-arrow {
    opacity: 1;
    transform: translateX(0);
}

.contact-link:hover .contact-arrow svg {
    transform: translateX(4px);
}

.contact-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: rgba(59, 130, 246, 0.1);
    border-radius: 8px;
    flex-shrink: 0;
}

.contact-icon svg {
    color: var(--accent-primary);
}

.contact-content {
    flex: 1;
    min-width: 0;
}

.contact-content h3 {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0 0 4px 0;
}

.contact-content a,
.contact-content span {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9375rem;
    transition: color var(--transition-speed) var(--transition-smooth);
}

.contact-content a:hover {
    color: var(--accent-primary);
}

.contact-arrow {
    display: flex;
    align-items: center;
    opacity: 0.5;
    transform: translateX(-4px);
    transition: all var(--transition-speed) var(--transition-smooth);
}

.contact-arrow svg {
    color: var(--text-secondary);
    transition: transform var(--transition-speed) var(--transition-smooth);
}

/* Copy Email Button */
.copy-email-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    transition: all var(--transition-speed) var(--transition-smooth);
    display: inline-flex;
    align-items: center;
    vertical-align: middle;
}

.copy-email-btn:hover {
    border-color: var(--border-hover);
    background-color: var(--bg-card);
}

.copy-email-btn svg {
    stroke: var(--text-secondary);
    transition: stroke var(--transition-speed) var(--transition-smooth);
}

.copy-email-btn:hover svg {
    stroke: var(--text-primary);
}

.copy-email-btn.copied {
    border-color: var(--accent-primary);
}

.copy-email-btn.copied svg {
    stroke: var(--accent-primary);
}

/* Current Learning Section */
.current-learning {
    padding: 60px 0;
}

.current-learning h2 {
    margin-bottom: 3rem;
}

.learning-item {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    transition: all var(--transition-speed) var(--transition-smooth);
    min-width: 120px;
}

.learning-item:hover {
    border-color: var(--border-hover);
    background: var(--bg-secondary);
    transform: translateY(-2px);
}

.learning-item img {
    max-width: 40px;
    height: 40px;
    margin-bottom: 10px;
    object-fit: contain;
    opacity: 0.9;
}

.learning-item:hover img {
    opacity: 1;
}

.learning-item p {
    margin: 0;
    color: var(--text-secondary);
    font-size: 0.8125rem;
    font-weight: 500;
}

.learning-item:hover p {
    color: var(--text-primary);
}

/* Footer */
.footer {
    padding: 48px 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
    margin-top: 60px;
}

.footer p {
    margin: 0;
    font-size: 0.875rem;
    color: var(--text-tertiary);
}

/* Media Queries */
@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    .navbar-container {
        padding: 0 20px;
    }

    .theme-toggle {
        margin-right: 12px;
    }

    .hamburger {
        display: block;
    }

    .navbar-menu {
        position: fixed;
        top: 60px;
        right: -100%;
        width: calc(100vw - 40px);
        max-width: 320px;
        background-color: var(--bg-secondary);
        border: 1px solid var(--border-color);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        flex-direction: column;
        padding: 16px;
        border-radius: var(--border-radius-md);
        box-shadow: var(--shadow-lg);
        opacity: 0;
        gap: 0;
        margin-right: 20px;
    }

    .navbar-menu.active {
        right: 0;
        opacity: 1;
    }

    .navbar-menu li {
        margin: 0;
        padding: 12px 8px;
        border-bottom: 1px solid var(--border-color);
    }

    .navbar-menu li:last-child {
        border-bottom: none;
    }

    .navbar-menu a {
        display: block;
        font-size: 1rem;
    }

    .hamburger.active .hamburger-line:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .hamburger-line:nth-child(1) {
        transform: translateY(6px) rotate(45deg);
    }

    .hamburger.active .hamburger-line:nth-child(3) {
        transform: translateY(-6px) rotate(-45deg);
    }

    .hero {
        padding: 100px 0 60px;
    }

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

    .hero-subtitle {
        font-size: 1.125rem;
    }

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

    .btn-primary, .btn-secondary {
        width: 100%;
        justify-content: center;
    }

    section {
        padding: 40px 0;
    }

    h2 {
        font-size: 1.875rem;
        margin-bottom: 2rem;
    }

    .skills-grid {
        gap: 10px;
    }

    .skill-item {
        padding: 8px 16px 8px 8px;
    }

    .skill-item img {
        width: 28px;
        height: 28px;
    }

    .skill-item p {
        font-size: 0.9375rem;
    }

    .certifications ul {
        grid-template-columns: 1fr;
    }

    .project {
        padding: 24px;
    }

    .contacts p {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
    }

    .back-to-top {
        bottom: 24px;
        right: 24px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.625rem;
    }
}