/* ================================================
   カラーパレット & 変数定義
   ================================================ */
:root {
    --color-primary: #1a1a1a;
    --color-secondary: #2a2a2a;
    --color-accent: #4a4a4a;
    --color-text: #333333;
    --color-text-light: #666666;
    --color-background: #ffffff;
    --color-background-alt: #f8f8f8;
    --color-border: #e0e0e0;

    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', 'Hiragino Sans', 'Hiragino Kaku Gothic ProN', 'Yu Gothic', YuGothic, Meiryo, sans-serif;
    --font-secondary: 'Georgia', serif;

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;

    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.05);
    --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-heavy: 0 8px 32px rgba(0, 0, 0, 0.12);
}

/* ================================================
   リセット & ベーススタイル
   ================================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

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

/* ================================================
   タイポグラフィ
   ================================================ */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    letter-spacing: -0.02em;
    color: var(--color-primary);
}

h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: var(--spacing-md);
}

h2 {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin-bottom: var(--spacing-sm);
}

p {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-light);
    line-height: 1.8;
}

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

/* ================================================
   レイアウト & コンテナ
   ================================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container-wide {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container-narrow {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

section {
    padding: var(--spacing-xl) 0;
    position: relative;
}

/* ================================================
   ヘッダー & ナビゲーション
   ================================================ */
.header {
    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);
    transition: var(--transition-smooth);
}

.header.scrolled {
    box-shadow: var(--shadow-light);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--spacing-sm);
    padding-bottom: var(--spacing-sm);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    letter-spacing: -0.03em;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
}

.nav-menu a {
    color: var(--color-text);
    font-weight: 500;
    position: relative;
    padding: var(--spacing-xs) 0;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--color-primary);
    transition: width 0.3s ease;
}

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

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition-smooth);
}

/* ================================================
   ヒーローセクション
   ================================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 80px;
    background: linear-gradient(180deg, #ffffff 0%, #f8f8f8 100%);
}

.hero-content {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 1s ease forwards;
}

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

.hero h1 {
    margin-bottom: var(--spacing-md);
}

.hero .subtitle {
    font-size: clamp(1.125rem, 2vw, 1.5rem);
    color: var(--color-text-light);
    margin-bottom: var(--spacing-lg);
    line-height: 1.6;
}

.cta-buttons {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    flex-wrap: wrap;
}

/* ================================================
   ボタン
   ================================================ */
.btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 4px;
    cursor: pointer;
    transition: var(--transition-smooth);
    border: 2px solid transparent;
    text-align: center;
}

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

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

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

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

/* ================================================
   サービスセクション
   ================================================ */
.services {
    background-color: var(--color-background);
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-light);
    max-width: 600px;
    margin: 0 auto;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.service-card {
    padding: var(--spacing-md);
    background-color: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    transition: var(--transition-smooth);
    opacity: 0;
    transform: translateY(20px);
}

.service-card.animate {
    animation: fadeInUp 0.6s ease forwards;
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-medium);
    border-color: var(--color-accent);
}

.service-icon {
    width: 60px;
    height: 60px;
    background-color: var(--color-primary);
    color: var(--color-background);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

.service-card h3 {
    margin-bottom: var(--spacing-sm);
}

.service-card p {
    font-size: 0.9375rem;
}

/* ================================================
   特徴セクション
   ================================================ */
.features {
    background-color: var(--color-background-alt);
}

.features-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.feature-item {
    display: flex;
    gap: var(--spacing-sm);
    align-items: flex-start;
    padding: var(--spacing-sm);
    opacity: 0;
    transform: translateX(-20px);
}

.feature-item.animate {
    animation: fadeInRight 0.6s ease forwards;
}

@keyframes fadeInRight {
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.feature-icon {
    width: 40px;
    height: 40px;
    background-color: var(--color-primary);
    color: var(--color-background);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

.feature-content h4 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xs);
}

.feature-content p {
    font-size: 0.9375rem;
}

/* ================================================
   プロセスセクション
   ================================================ */
.process {
    background-color: var(--color-background);
}

.process-timeline {
    position: relative;
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md) 0;
}

.process-timeline::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background-color: var(--color-border);
}

.process-step {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    position: relative;
    opacity: 0;
    transform: scale(0.9);
}

.process-step.animate {
    animation: scaleIn 0.6s ease forwards;
}

@keyframes scaleIn {
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.process-step:nth-child(odd) {
    flex-direction: row;
}

.process-step:nth-child(even) {
    flex-direction: row-reverse;
}

.process-number {
    width: 60px;
    height: 60px;
    background-color: var(--color-primary);
    color: var(--color-background);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    flex-shrink: 0;
    position: relative;
    z-index: 1;
}

.process-content {
    flex: 1;
    background-color: var(--color-background-alt);
    padding: var(--spacing-md);
    border-radius: 8px;
    max-width: 45%;
}

.process-content h3 {
    margin-bottom: var(--spacing-sm);
}

/* ================================================
   CTA (Call to Action) セクション
   ================================================ */
.cta {
    background-color: var(--color-primary);
    color: var(--color-background);
    text-align: center;
}

.cta h2 {
    color: var(--color-background);
}

.cta p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
}

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

.cta .btn-primary:hover {
    background-color: var(--color-background-alt);
    border-color: var(--color-background-alt);
}

/* ================================================
   コンタクトセクション
   ================================================ */
.contact {
    background-color: var(--color-background-alt);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.contact-item {
    display: flex;
    gap: var(--spacing-sm);
    align-items: flex-start;
}

.contact-item-icon {
    width: 40px;
    height: 40px;
    background-color: var(--color-primary);
    color: var(--color-background);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group label {
    font-weight: 600;
    color: var(--color-primary);
    font-size: 0.9375rem;
}

.form-group input,
.form-group textarea {
    padding: 0.875rem;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    font-family: var(--font-primary);
    font-size: 1rem;
    transition: var(--transition-smooth);
    background-color: var(--color-background);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(26, 26, 26, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

/* ================================================
   フッター
   ================================================ */
.footer {
    background-color: var(--color-primary);
    color: var(--color-background);
    padding: var(--spacing-lg) 0 var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.footer-section h4 {
    color: var(--color-background);
    margin-bottom: var(--spacing-sm);
}

.footer-section p,
.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9375rem;
}

.footer-section a:hover {
    color: var(--color-background);
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-md);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
}

/* ================================================
   レスポンシブデザイン
   ================================================ */
@media (max-width: 968px) {
    .process-timeline::before {
        left: 30px;
    }

    .process-step:nth-child(odd),
    .process-step:nth-child(even) {
        flex-direction: row;
    }

    .process-content {
        max-width: 100%;
    }

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

@media (max-width: 768px) {
    :root {
        --spacing-lg: 3rem;
        --spacing-xl: 4rem;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background-color: var(--color-background);
        flex-direction: column;
        padding: var(--spacing-md);
        gap: 0;
        transition: left 0.3s ease;
        border-top: 1px solid var(--color-border);
    }

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

    .nav-menu li {
        width: 100%;
        border-bottom: 1px solid var(--color-border);
    }

    .nav-menu a {
        display: block;
        padding: var(--spacing-sm) 0;
    }

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

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

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

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }

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

    .btn {
        width: 100%;
    }
}

/* ================================================
   ユーティリティクラス
   ================================================ */
.text-center {
    text-align: center;
}

.mt-lg {
    margin-top: var(--spacing-lg);
}

.mb-lg {
    margin-bottom: var(--spacing-lg);
}

.fade-in {
    opacity: 0;
    animation: fadeIn 1s ease forwards;
}

@keyframes fadeIn {
    to {
        opacity: 1;
    }
}