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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #ffffff;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: transparent;
    backdrop-filter: none;
    box-shadow: none;
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2563eb;
    text-decoration: none;
}

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

.lang-switch {
    display: flex;
    align-items: center;
    gap: 8px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 0.9rem;
    padding: 6px 12px;
    border-radius: 6px;
    transition: background 0.3s ease;
}

.lang-switch:hover {
    background: #f1f5f9;
}

.lang-option {
    color: #64748b;
    transition: all 0.3s ease;
    cursor: pointer;
    font-weight: 500;
}

.lang-option.active {
    color: #2563eb;
    font-weight: 600;
}

.lang-option:hover {
    color: #2563eb;
}

.lang-divider {
    color: #cbd5e1;
}

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

.hamburger {
    width: 25px;
    height: 3px;
    background: #64748b;
    border-radius: 3px;
    transition: all 0.3s ease;
}

.mobile-menu-toggle.active .hamburger:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active .hamburger:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .hamburger:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

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

.nav-link {
    color: #64748b;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 8px 16px;
    border-radius: 6px;
    position: relative;
}

.nav-link:hover {
    color: #2563eb;
    background: #eff6ff;
}

.nav-link.active {
    color: #2563eb;
    font-weight: 600;
}

/* Hero Section */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 70px;
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    position: relative;
    overflow: hidden;
}

#particles-js {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 0;
    opacity: 0.7;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content-wrapper {
    display: flex;
    align-items: center;
    gap: 24px;
    margin-bottom: 20px;
}

.profile-photo {
    flex-shrink: 0;
}

.profile-photo img {
    width: 120px;
    height: 120px;
    border-radius: 16px;
    object-fit: cover;
    border: 4px solid #2563eb;
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.3);
}

.hero-text-content {
    flex: 1;
}

.hello {
    font-size: 1.1rem;
    color: #2563eb;
    font-weight: 500;
    margin-bottom: 8px;
}

.name {
    font-size: 3rem;
    font-weight: 800;
    color: #0f172a;
    margin-bottom: 8px;
    line-height: 1.1;
    white-space: nowrap;
}

.lang-ja .name {
    font-size: 2.5rem;
}

@media (max-width: 1200px) {
    .name {
        font-size: 2.5rem;
    }

    .lang-ja .name {
        font-size: 2rem;
    }
}

.title {
    font-size: 1.8rem;
    font-weight: 700;
    color: #475569;
    margin-bottom: 0;
}

.description {
    font-size: 1.25rem;
    color: #64748b;
    margin-bottom: 32px;
    line-height: 1.7;
}

.cta-buttons {
    display: flex;
    gap: 16px;
}

.btn {
    padding: 14px 32px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
}

.btn-primary {
    background: #2563eb;
    color: white;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(37, 99, 235, 0.3);
}

.btn-secondary {
    background: transparent;
    color: #2563eb;
    border: 2px solid #2563eb;
}

.btn-secondary:hover {
    background: #2563eb;
    color: white;
}

/* Code Window */
.code-window {
    background: #1e293b;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.window-header {
    background: #0f172a;
    padding: 12px 16px;
    display: flex;
    gap: 8px;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #eab308; }
.dot.green { background: #22c55e; }

.code-content {
    padding: 24px;
    font-family: 'Monaco', 'Courier New', monospace;
    font-size: 0.95rem;
    line-height: 1.8;
    color: #e2e8f0;
}

.code-content .keyword {
    color: #c792ea;
}

.code-content .string {
    color: #c3e88d;
}

/* Sections */
.section {
    padding: 100px 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 48px;
    text-align: center;
}

/* About Section */
.about-section {
    background: white;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-content p {
    font-size: 1.125rem;
    color: #475569;
    line-height: 1.8;
    margin-bottom: 24px;
}

/* Experience Section */
.experience-section {
    background: #f8fafc;
}

.journey-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    flex-wrap: nowrap;
}

.step-card {
    background: white;
    border-radius: 16px;
    padding: 20px 16px;
    flex: 1;
    min-width: 0;
    max-width: 220px;
    min-height: 280px;
    display: flex;
    flex-direction: column;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
    position: relative;
    border: 2px solid #e2e8f0;
}

.step-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

.step-card.highlight {
    background: linear-gradient(135deg, #fef2f2 0%, #fee2e2 100%);
    border-color: #ef4444;
}

.step-card.active {
    background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
    border-color: #2563eb;
    box-shadow: 0 8px 30px rgba(37, 99, 235, 0.2);
}

.step-icon {
    font-size: 2.2rem;
    text-align: center;
    margin: 6px 0 10px;
}

.step-title {
    font-size: 1rem;
    color: #0f172a;
    font-weight: 700;
    text-align: center;
    margin-bottom: 14px;
}

.step-details {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-top: auto;
}

.step-details-horizontal {
    display: flex;
    gap: 12px;
    margin-top: auto;
}

.wide-card {
    flex: 2;
    max-width: 450px;
}

.detail-row {
    display: flex;
    flex-direction: column;
    gap: 5px;
    padding: 10px;
    background: #f8fafc;
    border-radius: 8px;
    border-left: 3px solid #2563eb;
}

.step-card:not(.active) .detail-row {
    border-left-color: #cbd5e1;
}

.detail-period {
    font-size: 0.75rem;
    color: #64748b;
    font-weight: 600;
}

.detail-role {
    font-size: 0.88rem;
    color: #0f172a;
    font-weight: 700;
}

.detail-company {
    font-size: 0.8rem;
    color: #2563eb;
    font-weight: 500;
}

.detail-company a {
    color: #2563eb;
    text-decoration: none;
    transition: all 0.3s ease;
}

.detail-company a:hover {
    color: #1d4ed8;
    text-decoration: underline;
}

.detail-activities {
    font-size: 0.75rem;
    color: #64748b;
    font-style: italic;
}

.current-tag {
    display: inline-block;
    background: #2563eb;
    color: white;
    padding: 4px 10px;
    border-radius: 12px;
    font-size: 0.7rem;
    font-weight: 700;
    margin-top: 8px;
    letter-spacing: 0.5px;
}

.step-year {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    color: #ef4444;
    margin-top: auto;
}

.step-arrow {
    font-size: 1.5rem;
    color: #cbd5e1;
    font-weight: 300;
    flex-shrink: 0;
}

/* Skills Section */
.skills-section {
    background: white;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
}

.skill-category h3 {
    font-size: 1.25rem;
    color: #0f172a;
    margin-bottom: 16px;
    font-weight: 700;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.tag {
    background: white;
    color: #475569;
    padding: 8px 16px;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    border: 1px solid #e2e8f0;
    transition: all 0.3s ease;
}

.tag:hover {
    border-color: #2563eb;
    color: #2563eb;
    transform: translateY(-2px);
}

/* Contact Section */
.contact-section {
    background: #f8fafc;
    text-align: center;
}

.contact-text {
    font-size: 1.125rem;
    color: #475569;
    max-width: 600px;
    margin: 0 auto 40px;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: nowrap;
    max-width: 600px;
    margin: 0 auto;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 45px;
    height: 45px;
    padding: 0;
    background: white;
    border: 2px solid #e2e8f0;
    border-radius: 50%;
    color: #475569;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-link span {
    display: none;
}

.social-link svg {
    width: 20px;
    height: 20px;
}

.social-link:hover {
    border-color: #2563eb;
    color: #2563eb;
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(37, 99, 235, 0.2);
}

/* Footer */
.footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 40px 0;
    text-align: center;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-visual {
        order: -1;
    }

    .profile-photo img {
        width: 110px;
        height: 110px;
    }

    .name {
        font-size: 2.5rem;
    }

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

@media (max-width: 768px) {
    .nav-container {
        padding: 0 20px;
    }

    .nav-right {
        gap: 16px;
    }

    .lang-switch {
        font-size: 0.85rem;
        padding: 4px 8px;
    }

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

    .nav-links {
        position: fixed;
        top: 70px;
        right: -100%;
        width: 250px;
        height: calc(100vh - 70px);
        background: white;
        flex-direction: column;
        gap: 0;
        padding: 20px;
        box-shadow: -2px 0 10px rgba(0, 0, 0, 0.1);
        transition: right 0.3s ease;
        z-index: 999;
    }

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

    .nav-link {
        padding: 15px 20px;
        width: 100%;
        text-align: left;
        border-radius: 8px;
    }

    .container {
        padding: 0 20px;
    }

    .hero-container {
        padding: 40px 20px;
    }

    .hero-content-wrapper {
        flex-direction: column;
        text-align: center;
        gap: 16px;
    }

    .profile-photo img {
        width: 100px;
        height: 100px;
    }

    .name {
        font-size: 2.2rem;
    }

    .lang-ja .name {
        font-size: 1.8rem;
    }

    .title {
        font-size: 1.5rem;
    }

    .description {
        font-size: 1.1rem;
    }

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

    .btn {
        text-align: center;
    }

    .code-content {
        font-size: 0.8rem;
        padding: 16px;
    }

    .section {
        padding: 60px 0;
    }

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

    .journey-steps {
        flex-direction: column;
        gap: 32px;
    }

    .step-card {
        max-width: 100%;
        width: 100%;
    }

    .wide-card {
        max-width: 100%;
    }

    .step-details-horizontal {
        flex-direction: column;
    }

    .step-arrow {
        transform: rotate(90deg);
        font-size: 2.5rem;
    }

    .step-card:hover {
        transform: translateY(-4px);
    }

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

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

    .social-links {
        gap: 10px;
        flex-wrap: wrap;
    }

    .social-link {
        width: 40px;
        height: 40px;
    }

    .social-link svg {
        width: 18px;
        height: 18px;
    }
}