/* ===================================
   CSS Variables & Reset
   =================================== */
:root {
    /* Colors - より豊かなカラーパレット */
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    --secondary-color: #8b5cf6;
    --secondary-dark: #7c3aed;
    --accent-color: #06b6d4;
    --accent-orange: #f59e0b;
    --accent-pink: #ec4899;
    --accent-green: #10b981;
    
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-light: #94a3b8;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-dark: #0f172a;
    
    /* Gradients - より多様なグラデーション */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-blue: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
    --gradient-purple: linear-gradient(135deg, #8b5cf6 0%, #ec4899 100%);
    --gradient-cyan: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
    --gradient-orange: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);
    --gradient-green: linear-gradient(135deg, #10b981 0%, #06b6d4 100%);
    --gradient-hero: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 50%, #8b5cf6 100%);
    
    /* Spacing */
    --container-width: 1200px;
    --section-padding: 120px;
    --section-padding-mobile: 60px;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-japanese: 'Noto Sans JP', 'Yu Gothic', 'Hiragino Sans', sans-serif;
    
    /* Effects */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.18);
    
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-japanese);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.7;
    overflow-x: hidden;
}

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

/* ===================================
   Navigation
   =================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: var(--transition-normal);
    padding: 20px 0;
}

.navbar.scrolled {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: var(--shadow-md);
    padding: 12px 0;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    text-decoration: none;
}

.logo-text {
    font-size: 28px;
    font-weight: 900;
    color: #ffffff;
    font-family: var(--font-primary);
    letter-spacing: -0.5px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    transition: var(--transition-normal);
}

/* スクロール時のナビゲーションでロゴを暗くする */
.navbar.scrolled .logo-text {
    background: var(--gradient-blue);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: none;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 40px;
    align-items: center;
}

.nav-link {
    color: #ffffff;
    text-decoration: none;
    font-weight: 500;
    font-size: 15px;
    position: relative;
    transition: var(--transition-fast);
    padding: 8px 0;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

/* スクロール時のナビゲーションでリンクを暗くする */
.navbar.scrolled .nav-link {
    color: var(--text-primary);
    text-shadow: none;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: #ffffff;
    transition: var(--transition-normal);
}

/* スクロール後のアンダーライン */
.navbar.scrolled .nav-link::after {
    background: var(--gradient-blue);
}

.nav-link:hover {
    color: #ffffff;
}

.navbar.scrolled .nav-link:hover {
    color: var(--primary-color);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #ffffff;
    border-radius: 3px;
    transition: var(--transition-normal);
}

.navbar.scrolled .nav-toggle span {
    background: var(--text-primary);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: 80px;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('../images/tokyo-aerial.jpg') center/cover no-repeat;
    z-index: -1;
}

/* 画像の上にグラデーションオーバーレイで都会的な雰囲気を演出 */
.hero-bg::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.75) 0%, rgba(124, 58, 237, 0.65) 50%, rgba(236, 72, 153, 0.7) 100%);
    z-index: 1;
}

/* テキストの可読性を高める追加レイヤー */
.hero-bg::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at center, transparent 0%, rgba(15, 23, 42, 0.3) 100%);
    z-index: 2;
}

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.25;
    animation: float 20s ease-in-out infinite;
    z-index: 2;
}

.orb-1 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.35) 0%, transparent 70%);
    top: -10%;
    left: -10%;
    animation-delay: 0s;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(236, 72, 153, 0.3) 0%, transparent 70%);
    top: 40%;
    right: -5%;
    animation-delay: 5s;
}

.orb-3 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(6, 182, 212, 0.25) 0%, transparent 70%);
    bottom: -20%;
    left: 30%;
    animation-delay: 10s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(50px, -50px) scale(1.1); }
    66% { transform: translate(-30px, 30px) scale(0.9); }
}

.hero-container {
    position: relative;
    z-index: 3;
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.hero-title {
    font-size: clamp(42px, 6vw, 72px);
    font-weight: 900;
    line-height: 1.2;
    margin-bottom: 30px;
    color: #ffffff;
    letter-spacing: -2px;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-title .highlight {
    color: #ffffff;
    display: inline-block;
}

.hero-subtitle {
    font-size: clamp(20px, 3vw, 28px);
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 30px;
    line-height: 1.5;
    letter-spacing: 0.5px;
    text-shadow: 0 2px 15px rgba(0, 0, 0, 0.3);
}

.hero-description {
    font-size: clamp(15px, 1.8vw, 18px);
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 50px;
    line-height: 1.8;
    font-weight: 400;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.hero-cta {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    align-items: center;
}

.hero-scroll {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    color: rgba(255, 255, 255, 0.8);
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-top: 40px;
}

.scroll-line {
    width: 1px;
    height: 50px;
    background: linear-gradient(to bottom, rgba(255, 255, 255, 0.8), transparent);
    animation: scrollLine 2s ease-in-out infinite;
}

@keyframes scrollLine {
    0%, 100% { opacity: 0; transform: translateY(0); }
    50% { opacity: 1; transform: translateY(20px); }
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 36px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    border-radius: 50px;
    transition: var(--transition-normal);
    cursor: pointer;
    border: none;
    font-family: var(--font-japanese);
}

.btn-primary {
    background: var(--gradient-blue);
    color: white;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
    position: relative;
    overflow: hidden;
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: var(--transition-slow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
}

.btn-primary:hover::before {
    left: 100%;
}

.btn-secondary {
    background: white;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.btn-large {
    padding: 20px 48px;
    font-size: 18px;
}

/* ===================================
   Section Common Styles
   =================================== */
section {
    padding: var(--section-padding) 0;
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-label {
    display: inline-block;
    font-size: 14px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    color: var(--primary-color);
    margin-bottom: 16px;
    font-family: var(--font-primary);
}

.section-title {
    font-size: clamp(36px, 5vw, 52px);
    font-weight: 900;
    margin-bottom: 20px;
    color: var(--text-primary);
    letter-spacing: -1px;
}

.section-description {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ===================================
   Glass Card Effect
   =================================== */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    box-shadow: var(--shadow-lg);
}

/* ===================================
   Services Section
   =================================== */
.services {
    background: var(--bg-secondary);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 40px;
}

.service-card {
    padding: 48px 40px;
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient-blue);
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition-normal);
}

/* 各サービスカードに異なる色を適用 */
.service-card:nth-child(1)::before {
    background: var(--gradient-blue);
}

.service-card:nth-child(2)::before {
    background: var(--gradient-purple);
}

.service-card:nth-child(3)::before {
    background: var(--gradient-cyan);
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.service-card:hover::before {
    transform: scaleX(1);
}

.service-icon {
    width: 80px;
    height: 80px;
    border-radius: 20px;
    background: var(--gradient-blue);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 28px;
    font-size: 32px;
    color: white;
    transition: var(--transition-normal);
}

/* 各サービスアイコンに異なるグラデーションを適用 */
.service-card:nth-child(1) .service-icon {
    background: var(--gradient-blue);
}

.service-card:nth-child(2) .service-icon {
    background: var(--gradient-purple);
}

.service-card:nth-child(3) .service-icon {
    background: var(--gradient-cyan);
}

.service-card:hover .service-icon {
    transform: scale(1.1) rotate(5deg);
}

.service-title {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-primary);
    line-height: 1.4;
}

.service-description {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 24px;
}

.service-features {
    list-style: none;
}

.service-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 0;
    font-size: 14px;
    color: var(--text-secondary);
}

.service-features li i {
    color: var(--primary-color);
    font-size: 12px;
}

/* 各サービスカードのチェックマークに異なる色を適用 */
.service-card:nth-child(1) .service-features li i {
    color: var(--primary-color);
}

.service-card:nth-child(2) .service-features li i {
    color: var(--secondary-color);
}

.service-card:nth-child(3) .service-features li i {
    color: var(--accent-color);
}

/* ===================================
   Strengths Section
   =================================== */
.strengths-grid {
    display: grid;
    gap: 40px;
}

.strength-item {
    display: flex;
    gap: 32px;
    padding: 40px;
    background: white;
    border-radius: 20px;
    border-left: 4px solid transparent;
    transition: var(--transition-normal);
    box-shadow: var(--shadow-sm);
}

.strength-item:hover {
    border-left-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
    transform: translateX(8px);
}

/* 各強みアイテムに異なるボーダーカラーを適用 */
.strength-item:nth-child(1):hover {
    border-left-color: var(--primary-color);
}

.strength-item:nth-child(2):hover {
    border-left-color: var(--secondary-color);
}

.strength-item:nth-child(3):hover {
    border-left-color: var(--accent-color);
}

.strength-item:nth-child(4):hover {
    border-left-color: var(--accent-green);
}

.strength-number {
    font-size: 48px;
    font-weight: 900;
    background: var(--gradient-blue);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-family: var(--font-primary);
    line-height: 1;
    flex-shrink: 0;
}

/* 各強みナンバーに異なるグラデーションを適用 */
.strength-item:nth-child(1) .strength-number {
    background: var(--gradient-blue);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.strength-item:nth-child(2) .strength-number {
    background: var(--gradient-purple);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.strength-item:nth-child(3) .strength-number {
    background: var(--gradient-cyan);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.strength-item:nth-child(4) .strength-number {
    background: var(--gradient-green);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.strength-content {
    flex: 1;
}

.strength-title {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 12px;
}

.strength-title i {
    color: var(--primary-color);
    font-size: 20px;
}

/* 各強みアイコンに異なる色を適用 */
.strength-item:nth-child(1) .strength-title i {
    color: var(--primary-color);
}

.strength-item:nth-child(2) .strength-title i {
    color: var(--secondary-color);
}

.strength-item:nth-child(3) .strength-title i {
    color: var(--accent-color);
}

.strength-item:nth-child(4) .strength-title i {
    color: var(--accent-green);
}

.strength-description {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ===================================
   Contact Section
   =================================== */
.contact {
    background: var(--bg-secondary);
}

.contact-wrapper {
    padding: 80px 60px;
    text-align: center;
}

.contact-content {
    max-width: 700px;
    margin: 0 auto;
}

.contact-description {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 50px;
    line-height: 1.8;
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: var(--bg-dark);
    color: var(--text-light);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-logo {
    margin-bottom: 16px;
}

.footer-logo .logo-text {
    font-size: 28px;
    background: linear-gradient(135deg, #60a5fa 0%, #a78bfa 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-tagline {
    font-size: 14px;
    color: var(--text-light);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.footer-column h4 {
    font-size: 16px;
    font-weight: 700;
    color: white;
    margin-bottom: 20px;
}

.footer-column ul {
    list-style: none;
}

.footer-column ul li {
    margin-bottom: 12px;
}

.footer-column a {
    color: var(--text-light);
    text-decoration: none;
    font-size: 14px;
    transition: var(--transition-fast);
}

.footer-column a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-bottom p {
    font-size: 14px;
    color: var(--text-light);
}

/* ===================================
   Animations
   =================================== */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 968px) {
    :root {
        --section-padding: 80px;
    }
    
    .nav-list {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        width: 100%;
        padding: 40px 24px;
        box-shadow: var(--shadow-lg);
        transition: var(--transition-normal);
        gap: 20px;
        align-items: flex-start;
    }
    
    .nav-list.active {
        left: 0;
    }
    
    /* モバイルメニューのリンクは常に暗色 */
    .nav-list .nav-link {
        color: var(--text-primary);
        text-shadow: none;
    }
    
    .nav-list .nav-link::after {
        background: var(--gradient-blue);
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(7px, 7px);
    }
    
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: stretch;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .strength-item {
        flex-direction: column;
        padding: 30px;
    }
    
    .strength-number {
        font-size: 36px;
    }
    
    .contact-wrapper {
        padding: 60px 30px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .hero-scroll {
        margin-top: 30px;
    }
    
    .hero-cta {
        flex-direction: column;
        width: 100%;
    }
    
    .hero-cta .btn {
        width: 100%;
        justify-content: center;
    }
}

@media (max-width: 640px) {
    :root {
        --section-padding: 60px;
    }
    
    .hero {
        min-height: 90vh;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .section-title {
        font-size: 32px;
    }
    
    .service-card {
        padding: 36px 24px;
    }
    
    .btn {
        padding: 14px 28px;
        font-size: 15px;
    }
    
    .btn-large {
        padding: 16px 36px;
        font-size: 16px;
    }
    
    .hero-scroll {
        margin-top: 25px;
    }
}