/* ============================================
   VARIABLES & RESET
   ============================================ */
:root {
    --color-bg: #0a0a0b;
    --color-bg-alt: #111113;
    --color-surface: #18181b;
    --color-surface-hover: #1f1f23;
    --color-border: #27272a;
    --color-border-light: #3f3f46;
    --color-text: #fafafa;
    --color-text-secondary: #a1a1aa;
    --color-text-muted: #71717a;
    --color-accent: #3b82f6;
    --color-accent-hover: #60a5fa;
    --color-accent-soft: rgba(59, 130, 246, 0.1);
    --color-accent-border: rgba(59, 130, 246, 0.3);
    --color-green: #22c55e;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --container-max: 1100px;
    --nav-height: 64px;
    --radius: 12px;
    --radius-sm: 8px;
    --transition: 0.2s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
}

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

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

ul {
    list-style: none;
}

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

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

.section {
    padding: 100px 0;
}

#about {
    padding-top: 0;
}

.section-alt {
    background: var(--color-bg-alt);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 48px;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 48px;
    height: 3px;
    background: var(--color-accent);
    border-radius: 2px;
}

/* ============================================
   NAVIGATION
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(10, 10, 11, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    z-index: 1000;
    transition: border-color var(--transition), background var(--transition);
}

.nav.scrolled {
    border-bottom-color: var(--color-border);
    background: rgba(10, 10, 11, 0.95);
}

.nav-inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text) !important;
    font-family: var(--font-mono);
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    transition: color var(--transition);
}

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

.nav-links a.active-link {
    color: var(--color-text);
}

.nav-cta {
    background: var(--color-accent);
    color: var(--color-text) !important;
    padding: 8px 20px;
    border-radius: 8px;
    font-weight: 500;
    transition: background var(--transition) !important;
}

.nav-cta:hover {
    background: var(--color-accent-hover) !important;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: 1px;
    transition: transform var(--transition), opacity var(--transition);
}

/* ============================================
   HERO
   ============================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: var(--nav-height);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 64px;
    align-items: center;
}

.hero-greeting {
    font-family: var(--font-mono);
    color: var(--color-accent);
    font-size: 1rem;
    margin-bottom: 12px;
    font-weight: 500;
}

.hero-name {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -1.5px;
    margin-bottom: 12px;
}

.hero-title {
    font-size: clamp(1.1rem, 2.5vw, 1.5rem);
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: 24px;
}

.hero-summary {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    max-width: 560px;
    line-height: 1.8;
    margin-bottom: 36px;
}

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

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

.hero-photo {
    width: 300px;
    height: 340px;
    border-radius: var(--radius);
    object-fit: cover;
    border: 2px solid var(--color-border);
    transition: border-color var(--transition);
}

.hero-photo:hover {
    border-color: var(--color-accent-border);
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius-sm);
    font-weight: 500;
    font-size: 0.9rem;
    transition: all var(--transition);
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--color-accent);
    color: #fff;
    border-color: var(--color-accent);
}

.btn-primary:hover {
    background: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
    color: #fff;
}

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

.btn-secondary:hover {
    border-color: var(--color-border-light);
    color: var(--color-text);
    background: var(--color-surface);
}

.btn-lg {
    padding: 14px 28px;
    font-size: 1rem;
}

/* ============================================
   ABOUT
   ============================================ */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 64px;
    align-items: start;
}

.about-text p {
    color: var(--color-text-secondary);
    margin-bottom: 20px;
    font-size: 1.05rem;
}

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

.about-list {
    list-style: none;
}

.about-list li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 14px;
    color: var(--color-text-secondary);
    font-size: 1.02rem;
    line-height: 1.7;
}

.about-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: 700;
    font-size: 1.1rem;
    line-height: 1.7;
}

.about-list li:last-child {
    margin-bottom: 0;
}

.about-highlights {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.highlight-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 24px;
    text-align: center;
    transition: border-color var(--transition), transform var(--transition);
}

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

.highlight-number {
    display: block;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-accent);
    font-family: var(--font-mono);
    margin-bottom: 4px;
}

.highlight-label {
    display: block;
    font-size: 0.8rem;
    color: var(--color-text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* ============================================
   EXPERIENCE TIMELINE
   ============================================ */
.timeline {
    position: relative;
    padding-left: 0;
}

.timeline::before {
    display: none;
}

.timeline-item {
    position: relative;
    margin-bottom: 48px;
}

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

.timeline-marker {
    display: none;
}

.timeline-content {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
    transition: border-color var(--transition);
}

.timeline-content:hover {
    border-color: var(--color-border-light);
}

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

.timeline-header h3 {
    font-size: 1.15rem;
    font-weight: 600;
}

.timeline-company {
    color: var(--color-accent);
    font-size: 0.9rem;
    font-weight: 500;
    margin-top: 2px;
}

.timeline-date {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    font-family: var(--font-mono);
    white-space: nowrap;
    flex-shrink: 0;
}

.timeline-desc {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
}

.timeline-achievements {
    list-style: none;
    margin-bottom: 16px;
}

.timeline-achievements li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
}

.timeline-achievements li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-accent);
    font-weight: 600;
}

.timeline-achievements li:last-child {
    margin-bottom: 0;
}

.timeline-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.timeline-tags span {
    font-size: 0.75rem;
    padding: 4px 10px;
    background: var(--color-accent-soft);
    color: var(--color-accent);
    border-radius: 6px;
    font-weight: 500;
    font-family: var(--font-mono);
}

/* Previous experience compact grid */
.prev-experience {
    margin-top: 48px;
}

.prev-experience-heading {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--color-border);
}

.prev-roles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.prev-role {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 20px;
    transition: border-color var(--transition);
}

.prev-role:hover {
    border-color: var(--color-border-light);
}

.prev-role-title {
    display: block;
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--color-text);
    margin-bottom: 6px;
}

.prev-role-field {
    display: block;
    font-size: 0.82rem;
    color: var(--color-text-muted);
    line-height: 1.5;
}

/* ============================================
   PROJECTS
   ============================================ */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.project-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
    transition: border-color var(--transition), transform var(--transition);
    position: relative;
}

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

.project-featured {
    grid-column: 1 / -1;
    border-color: var(--color-accent-border);
    background: linear-gradient(135deg, var(--color-surface) 0%, rgba(59, 130, 246, 0.03) 100%);
}

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

.project-badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    padding: 4px 10px;
    background: var(--color-accent);
    color: #fff;
    border-radius: 6px;
    margin-bottom: 16px;
}

.project-card h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.project-subtitle {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-bottom: 12px;
    font-family: var(--font-mono);
}

.project-card > p {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    margin-bottom: 16px;
    line-height: 1.7;
}

.project-links {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
}

.project-links a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
    font-weight: 500;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.project-tags span {
    font-size: 0.75rem;
    padding: 4px 10px;
    background: var(--color-accent-soft);
    color: var(--color-accent);
    border-radius: 6px;
    font-weight: 500;
    font-family: var(--font-mono);
}

/* ============================================
   SKILLS
   ============================================ */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.skill-group {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
}

.skill-group h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--color-text);
}

.skill-group h3 svg {
    color: var(--color-accent);
    flex-shrink: 0;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-tags span {
    font-size: 0.8rem;
    padding: 6px 14px;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 20px;
    color: var(--color-text-secondary);
    font-weight: 500;
    transition: all var(--transition);
}

.skill-tags span:hover {
    border-color: var(--color-accent-border);
    color: var(--color-accent);
    background: var(--color-accent-soft);
}

/* ============================================
   SPEAKING & WRITING
   ============================================ */
.speaking-rows {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.speaking-row {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 20px 28px;
    display: flex;
    align-items: center;
    gap: 24px;
    transition: border-color var(--transition);
}

.speaking-row:hover {
    border-color: var(--color-border-light);
}

.speaking-row-label {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    white-space: nowrap;
    flex-shrink: 0;
    min-width: 140px;
}

.speaking-row-label svg {
    color: var(--color-accent);
    flex-shrink: 0;
}

.speaking-row-items {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.speaking-row-items span {
    font-size: 0.82rem;
    padding: 6px 14px;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 20px;
    color: var(--color-text-secondary);
    font-weight: 500;
    transition: all var(--transition);
}

.speaking-row-items span:hover {
    border-color: var(--color-accent-border);
    color: var(--color-accent);
    background: var(--color-accent-soft);
}

/* ============================================
   EDUCATION
   ============================================ */
.education-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.education-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 28px;
}

.education-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.education-card p {
    color: var(--color-text-secondary);
    font-size: 0.9rem;
}

.education-card ul {
    list-style: none;
}

.education-card ul li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
}

.education-card ul li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-accent);
}

.education-card ul li:last-child {
    margin-bottom: 0;
}

/* ============================================
   CONTACT
   ============================================ */
.contact-block {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-block .section-title::after {
    left: 50%;
    transform: translateX(-50%);
}

.contact-text {
    color: var(--color-text-secondary);
    font-size: 1.1rem;
    margin-bottom: 36px;
    line-height: 1.8;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    padding: 32px 0;
    border-top: 1px solid var(--color-border);
    text-align: center;
}

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

/* ============================================
   ANIMATIONS
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 900px) {
    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-visual {
        order: -1;
    }

    .hero-photo {
        width: 200px;
        height: 240px;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

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

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

    .project-featured {
        grid-column: auto;
    }

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

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

@media (max-width: 640px) {
    .section {
        padding: 72px 0;
    }

    .section-title {
        font-size: 1.6rem;
        margin-bottom: 36px;
    }

    .prev-roles-grid {
        grid-template-columns: 1fr;
    }

    .speaking-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .speaking-row-label {
        min-width: auto;
    }

    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: transform 0.3s ease, opacity 0.3s ease;
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }

    .nav-toggle {
        display: flex;
    }

    .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 {
        min-height: auto;
        padding-top: calc(var(--nav-height) + 48px);
        padding-bottom: 48px;
    }

    .hero-photo {
        width: 160px;
        height: 200px;
    }

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

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

    .timeline {
        padding-left: 24px;
    }

    .timeline-header {
        flex-direction: column;
        gap: 4px;
    }

    .timeline-content {
        padding: 20px;
    }

    .contact-links {
        flex-direction: column;
        align-items: center;
    }
}