:root {
    /* Color System */
    --primary-50: #fce8e9;
    --primary-100: #fac5c6;
    --primary-200: #f69fa1;
    --primary-300: #f1787b;
    --primary-400: #ec5255;
    --primary-500: #E13C3F;
    /* Brand Color */
    --primary-600: #b43032;
    --primary-700: #872426;
    --primary-800: #5a1819;
    --primary-900: #2d0c0d;

    --neutral-50: #fafafa;
    --neutral-100: #f5f5f5;
    --neutral-200: #e5e5e5;
    --neutral-300: #d4d4d4;
    --neutral-400: #a3a3a3;
    --neutral-500: #737373;
    --neutral-600: #525252;
    --neutral-700: #404040;
    --neutral-800: #262626;
    --neutral-900: #171717;

    --white: #ffffff;
    --black: #000000;

    /* Spacing Scale */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    --space-3xl: 64px;
    --space-4xl: 96px;

    /* Typography */
    --font-base: 'Noto Sans JP', sans-serif;
    --font-heading: 'Noto Sans JP', sans-serif;

    /* Layout */
    --max-width: 1200px;
    --header-height: 80px;
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* Z-Index */
    --z-header: 100;
    --z-hero: 1;
    --z-modal: 1000;
}

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

body {
    font-family: var(--font-base);
    color: var(--neutral-800);
    line-height: 1.6;
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

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

/* Utilities */
.container {
    width: 90%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

.bg-light {
    background-color: var(--neutral-50);
}

.text-center {
    text-align: center;
}

.mt-4 {
    margin-top: var(--space-md);
}

.mb-8 {
    margin-bottom: var(--space-xl);
}

/* Responsive Display Utilities */
.pc-only {
    display: inline;
}

.sp-only {
    display: none;
}

.section {
    padding: var(--space-4xl) 0;
    position: relative;
    z-index: auto;
    /* Fix z-index issue */
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-3xl);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    /* Strengthened */
    margin-bottom: var(--space-md);
    position: relative;
    display: inline-block;
    color: var(--neutral-900);
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-500), var(--primary-300));
    margin: var(--space-md) auto 0;
    border-radius: var(--radius-full);
}

.section-desc {
    color: var(--neutral-600);
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 36px;
    border-radius: var(--radius-full);
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: none;
    text-align: center;
    font-size: 1rem;
    letter-spacing: 0.02em;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
    color: var(--white);
    box-shadow: 0 4px 12px rgba(225, 60, 63, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(225, 60, 63, 0.4);
    background: linear-gradient(135deg, var(--primary-400), var(--primary-500));
}

.btn-lg {
    padding: 18px 48px;
    font-size: 1.25rem;
}

.btn-block {
    display: flex;
    width: 100%;
}

/* Header */
.header {
    height: var(--header-height);
    background-color: rgba(255, 255, 255, 0.95);
    /* Slightly more opaque */
    backdrop-filter: blur(12px);
    position: sticky;
    top: 0;
    left: 0;
    width: 100%;
    z-index: var(--z-header);
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
    width: 90%;
    max-width: var(--max-width);
    margin: 0 auto;
}

.logo {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
    align-items: center;
}

.logo-text {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--primary-500);
    letter-spacing: -0.02em;
}

.logo-sub {
    font-size: 0.7rem;
    color: var(--neutral-500);
    letter-spacing: 0.05em;
    font-weight: 500;
}

/* Added flex to .nav to align list and button */
.nav {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-list {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-list a {
    font-weight: 500;
    font-size: 0.95rem;
    color: var(--neutral-700);
}

.nav-list a:hover {
    color: var(--primary-500);
}

.header-cta {
    padding: 10px 24px;
    font-size: 0.9rem;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-xs);
}

/* Hero */
.hero {
    padding-top: var(--space-4xl);
    padding-bottom: var(--space-4xl);
    background-color: var(--neutral-50);
    /* Light background */
    position: relative;
    overflow: hidden;
}

.hero-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-3xl);
}

.hero-content {
    flex: 1;
    max-width: 600px;
    z-index: 2;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3.5rem);
    /* Fluid typography */
    line-height: 1.3;
    margin-bottom: var(--space-lg);
    font-weight: 900;
    color: var(--neutral-900);
    /* Dark text */
    word-break: keep-all;
    /* Prevent word breaking */
    overflow-wrap: normal;
}

.highlight {
    color: var(--neutral-900);
    background: linear-gradient(transparent 70%, var(--primary-100) 70%);
    /* Red underline */
    padding: 0 4px;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--neutral-600);
    /* Dark gray */
    margin-bottom: var(--space-xl);
    line-height: 1.8;
    font-weight: 500;
}

.hero-image {
    flex: 1;
    position: relative;
    z-index: 1;
}

.hero-image img {
    width: 100%;
    height: auto;
    border-radius: var(--radius-xl);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    /* Optional: Add a subtle shape or transform */
}

/* Hero Stats */
.hero-stats {
    display: flex;
    gap: var(--space-md);
    margin-top: var(--space-2xl);
    flex-wrap: wrap;
}

.hero-stat-card {
    background: var(--white);
    border: 1px solid var(--neutral-100);
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    color: var(--neutral-800);
    min-width: 140px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease;
}

.hero-stat-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.hero-stat-label {
    display: block;
    font-size: 0.8rem;
    margin-bottom: var(--space-xs);
    color: var(--neutral-500);
    font-weight: 700;
}

.hero-stat-value {
    display: block;
    font-size: 1.1rem;
    font-weight: 800;
    line-height: 1.4;
    color: var(--neutral-900);
}

.highlight-text {
    color: var(--primary-500);
    /* Brand color */
    font-size: 1.4rem;
}

/* Responsive adjustments */
@media (max-width: 960px) {
    .hero-container {
        flex-direction: column;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
        margin-bottom: var(--space-xl);
        display: flex;
        flex-direction: column;
        align-items: center;
        padding: 0 var(--space-sm);
        /* Reduce padding slightly */
    }

    .hero-stats {
        justify-content: center;
        width: 100%;
    }

    .hero-image {
        width: 100%;
        max-width: 600px;
    }
}

@media (max-width: 768px) {
    .hero {
        padding-top: var(--space-2xl);
        padding-bottom: var(--space-3xl);
    }

    .hero-title {
        font-size: clamp(1.8rem, 6vw, 2.5rem);
        /* Smaller on mobile to fit "わくわくが止まらない" */
        line-height: 1.4;
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--space-sm);
        width: 100%;
    }

    .hero-stat-card {
        width: 100%;
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: var(--space-md);
        text-align: left;
    }

    .hero-stat-value br {
        display: none;
    }

    .hero-stat-value {
        text-align: right;
    }
}

/* About */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-3xl);
    align-items: center;
}

.about-lead {
    font-size: 1.75rem;
    margin-bottom: var(--space-lg);
    color: var(--primary-600);
    font-weight: 700;
    line-height: 1.4;
}

.feature-list {
    margin-top: var(--space-lg);
}

.feature-list li {
    margin-bottom: var(--space-md);
    padding-left: 32px;
    position: relative;
    font-weight: 600;
    font-size: 1.1rem;
}

.feature-list li::before {
    content: '✔';
    position: absolute;
    left: 0;
    top: 2px;
    color: var(--primary-500);
    font-weight: 800;
}

.about-image {
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
}

/* Service Process */
.service-process {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: var(--space-lg);
}

.process-step {
    flex: 1;
    min-width: 180px;
    text-align: center;
    padding: var(--space-lg);
    background: var(--white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--neutral-200);
    transition: all 0.3s ease;
}

.process-step:hover {
    transform: translateY(-8px);
    border-color: var(--primary-200);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.06);
}

.step-number {
    font-size: 3rem;
    font-weight: 900;
    color: var(--primary-100);
    line-height: 1;
    margin-bottom: var(--space-sm);
}

.step-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
}

.step-desc {
    font-size: 0.9rem;
    color: var(--neutral-500);
}

.process-arrow {
    align-self: center;
    width: 24px;
    height: 24px;
    border-top: 3px solid var(--neutral-300);
    border-right: 3px solid var(--neutral-300);
    transform: rotate(45deg);
    margin-top: -20px;
}

.service-note {
    text-align: center;
    margin-top: var(--space-2xl);
    font-weight: 700;
    color: var(--primary-600);
    background: var(--primary-50);
    display: inline-block;
    padding: var(--space-sm) var(--space-lg);
    border-radius: var(--radius-full);
}

/* Case Studies */
.case-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-2xl);
}

.case-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
    transition: all 0.3s ease;
    border: 1px solid var(--neutral-100);
}

.case-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.08);
}

.case-img {
    height: 220px;
    overflow: hidden;
    position: relative;
}

.case-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.case-card:hover .case-img img {
    transform: scale(1.08);
}

.case-body {
    padding: var(--space-lg);
}

.case-tag {
    display: inline-block;
    padding: 6px 14px;
    background-color: var(--primary-50);
    color: var(--primary-600);
    font-size: 0.75rem;
    font-weight: 700;
    border-radius: var(--radius-sm);
    margin-bottom: var(--space-md);
}

.case-title {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
    line-height: 1.4;
}

.case-text {
    font-size: 0.95rem;
    color: var(--neutral-600);
    margin-bottom: var(--space-md);
    /* Adjusted margin */
}

.case-stats {
    display: flex;
    justify-content: center;
    gap: var(--space-3xl);
    margin-top: var(--space-2xl);
    padding: var(--space-xl);
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.04);
}

.stat-item {
    text-align: center;
}

.stat-label {
    display: block;
    font-size: 0.9rem;
    color: var(--neutral-500);
    margin-bottom: var(--space-xs);
    font-weight: 600;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-600);
}

/* Team */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-xl);
}

.team-member {
    text-align: center;
    padding: var(--space-2xl) var(--space-lg);
    border: 1px solid var(--neutral-200);
    border-radius: var(--radius-lg);
    background: var(--white);
    transition: all 0.3s ease;
}

.team-member:hover {
    border-color: var(--primary-200);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.05);
}

.member-role {
    display: inline-block;
    font-family: serif;
    font-style: italic;
    font-size: 1.25rem;
    color: var(--primary-500);
    margin-bottom: var(--space-md);
}

.member-title {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
}

.member-desc {
    color: var(--neutral-600);
    font-size: 1rem;
}

/* FAQ */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--neutral-200);
}

.faq-question {
    width: 100%;
    text-align: left;
    padding: var(--space-lg) 0;
    background: none;
    border: none;
    font-size: 1.15rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--neutral-800);
    transition: color 0.3s;
}

.faq-question:hover {
    color: var(--primary-500);
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--primary-500);
    transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.faq-answer p {
    padding-bottom: var(--space-lg);
    color: var(--neutral-600);
    line-height: 1.8;
}

/* Contact */
.contact-section {
    background: linear-gradient(135deg, var(--primary-600) 0%, var(--primary-400) 100%);
    color: var(--white);
}

.contact-box {
    max-width: 600px;
    margin: 0 auto;
    background: var(--white);
    padding: var(--space-3xl);
    border-radius: var(--radius-xl);
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.2);
    color: var(--neutral-800);
}

.contact-title {
    text-align: center;
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: var(--space-md);
}

.contact-desc {
    text-align: center;
    margin-bottom: var(--space-2xl);
    color: var(--neutral-500);
}

.form-group {
    margin-bottom: var(--space-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--space-xs);
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--neutral-700);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px;
    border: 2px solid var(--neutral-200);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    transition: all 0.3s;
    background-color: var(--neutral-50);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-500);
    background-color: var(--white);
    box-shadow: 0 0 0 4px var(--primary-50);
}

/* Footer */
.footer {
    background-color: var(--neutral-900);
    color: var(--white);
    padding: var(--space-3xl) 0 var(--space-lg);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-2xl);
    border-bottom: 1px solid var(--neutral-800);
    padding-bottom: var(--space-2xl);
}

.footer-logo .logo-text {
    color: var(--white);
}

.footer-tagline {
    color: var(--neutral-500);
    font-size: 0.85rem;
    margin-top: var(--space-xs);
}

.footer-links a {
    color: var(--neutral-400);
    margin-left: var(--space-xl);
    font-size: 0.9rem;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--white);
}

.footer-copyright {
    text-align: center;
    color: var(--neutral-600);
    font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 768px) {
    :root {
        --header-height: 60px;
        --space-4xl: 64px;
        /* Reduce section padding */
        --space-3xl: 48px;
    }

    /* Typography Adjustments */
    .section-title {
        font-size: 1.75rem;
        /* Smaller heading */
    }

    .section-desc {
        font-size: 0.95rem;
        padding: 0 var(--space-sm);
    }

    .hero {
        flex-direction: column-reverse;
        text-align: center;
        padding-top: var(--space-2xl);
        gap: var(--space-xl);
    }

    .hero-title {
        font-size: 2.0rem;
        /* Smaller hero title for mobile */
        line-height: 1.4;
    }

    .hero-subtitle {
        font-size: 1rem;
        line-height: 1.6;
    }

    /* Responsive Display Utilities */
    .pc-only {
        display: none;
    }

    .sp-only {
        display: inline;
    }

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

    .about-lead {
        font-size: 1.4rem;
    }

    /* Stats Section Mobile Optimization */
    .case-stats {
        flex-direction: column;
        gap: var(--space-xl);
        padding: var(--space-lg);
    }

    .stat-value {
        font-size: 2rem;
        /* Larger value for readability */
    }

    .process-arrow {
        display: none;
    }

    .nav {
        display: none;
        position: absolute;
        top: var(--header-height);
        left: 0;
        width: 100%;
        background: var(--white);
        padding: var(--space-lg);
        box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
        border-top: 1px solid var(--neutral-100);
    }

    .nav.active {
        display: block;
        animation: slideDown 0.3s ease forwards;
    }

    @keyframes slideDown {
        from {
            opacity: 0;
            transform: translateY(-10px);
        }

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

    .nav-list {
        flex-direction: column;
        gap: var(--space-md);
        margin-bottom: var(--space-lg);
    }

    .menu-toggle {
        display: block;
        width: 30px;
        height: 20px;
        position: relative;
    }

    .menu-toggle span {
        display: block;
        width: 100%;
        height: 2px;
        background-color: var(--neutral-800);
        position: absolute;
        transition: 0.3s;
    }

    .menu-toggle span:nth-child(1) {
        top: 0;
    }

    .menu-toggle span:nth-child(2) {
        top: 9px;
    }

    .menu-toggle span:nth-child(3) {
        top: 18px;
    }

    .menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg);
        top: 9px;
    }

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

    .menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg);
        top: 9px;
    }

    .contact-box {
        padding: var(--space-xl);
    }

    .contact-title {
        font-size: 1.8rem;
    }
}