/**
 * TC Helicon - スタイルシート（完全版）
 * 共通ヘッダー（position: fixed, z-index: 1000, height: 64px）との共存対応
 */

/* ============================================
   CSS Variables
============================================ */
:root {
    /* ボーカル系カラー */
    --tc-vocal-primary: #0099cc;
    --tc-vocal-secondary: #00b894;
    --tc-vocal-light: #e8f6fc;
    --tc-vocal-bg: #f0f9fc;
    
    /* ゲーミング系カラー */
    --tc-gaming-primary: #9b59b6;
    --tc-gaming-secondary: #e74c3c;
    --tc-gaming-light: #f5eef8;
    --tc-gaming-bg: #faf5fc;
    
    /* ベースカラー（明るい） */
    --tc-white: #ffffff;
    --tc-bg-light: #f8f9fa;
    --tc-bg-gray: #f1f3f4;
    --tc-text-dark: #1a1a2e;
    --tc-text-body: #444444;
    --tc-text-muted: #777777;
    --tc-border: #e0e0e0;
    --tc-border-light: #eeeeee;
    
    /* Heroセクション用（暗め） */
    --tc-hero-dark: #1a1a2e;
    --tc-vocal-gradient: linear-gradient(135deg, #1e3a5f 0%, #2a5298 50%, #3d7ab8 100%);
    --tc-gaming-gradient: linear-gradient(135deg, #4a2c6a 0%, #6b3fa0 50%, #9055d0 100%);
    
    /* ヘッダー高さの変数（共通ヘッダー: 64px） */
    --header-height: 64px;
    --brand-nav-height: 45px;
    --total-nav-height: 109px;
    
    --tc-transition: all 0.3s ease;
    --tc-shadow: 0 2px 10px rgba(0,0,0,0.08);
    --tc-shadow-hover: 0 8px 25px rgba(0,0,0,0.12);
}

/* ============================================
   ブランドナビ - 共通ヘッダーの下に固定
============================================ */
.tc-helicon-brand-nav {
    display: block;
    background: #1a1a1a;
    padding: 12px 0;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    width: 100%;
    z-index: 999;
    box-sizing: border-box;
}

.tc-helicon-brand-nav .brand-nav-container {
    max-width: 100%;
    width: 100%;
    margin: 0 auto;
    padding: 0 30px;
    box-sizing: border-box;
}

.tc-helicon-brand-nav .brand-nav-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    list-style: none;
    margin: 0;
    padding: 0;
    flex-wrap: wrap;
}

.tc-helicon-brand-nav .brand-nav-links li a {
    color: #fff;
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.5px;
    transition: color 0.2s ease;
}

.tc-helicon-brand-nav .brand-nav-links li a:hover {
    color: #00a0e9;
}

.tc-helicon-brand-nav .brand-nav-links li a.active {
    color: #00a0e9;
    border-bottom: 2px solid #00a0e9;
    padding-bottom: 3px;
}

.tc-helicon-brand-nav .external-icon {
    font-size: 10px;
    margin-left: 3px;
    opacity: 0.7;
}

/* ============================================
   Hero Split Section
============================================ */
.tc-hero-split {
    display: flex;
    min-height: 100vh;
    background: var(--tc-hero-dark);
    padding-top: var(--total-nav-height);
    margin-top: 0;
}

.tc-hero-logo {
    position: absolute;
    top: calc(var(--total-nav-height) + 40px);
    left: 50%;
    transform: translateX(-50%);
    z-index: 100;
}

.tc-hero-logo img {
    height: 90px;
    width: auto;
    display: block;
    filter: drop-shadow(0 2px 10px rgba(0, 0, 0, 0.3));
}

.tc-category-panel {
    flex: 1;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    color: var(--tc-white);
    overflow: hidden;
    transition: flex 0.5s ease;
}

.tc-category-panel:hover {
    flex: 1.3;
}

.panel-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    transition: transform 0.5s ease, filter 0.5s ease;
    filter: brightness(0.8);
}

.tc-category-panel:hover .panel-bg {
    transform: scale(1.1);
    filter: brightness(1);
}

.panel-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transition: opacity 0.3s ease;
}

.vocal-panel .panel-overlay {
    background: linear-gradient(135deg, 
        rgba(30, 58, 95, 0.8) 0%, 
        rgba(42, 82, 152, 0.75) 50%, 
        rgba(61, 122, 184, 0.7) 100%);
}

.gaming-panel .panel-overlay {
    background: linear-gradient(135deg, 
        rgba(74, 44, 106, 0.8) 0%, 
        rgba(107, 63, 160, 0.75) 50%, 
        rgba(144, 85, 208, 0.7) 100%);
}

.tc-category-panel:hover .panel-overlay {
    opacity: 0.6;
}

.panel-content {
    position: relative;
    z-index: 10;
    text-align: center;
    padding: 40px;
    margin-top: 40px;
}

.panel-label {
    display: inline-block;
    font-size: 11px;
    letter-spacing: 3px;
    text-transform: uppercase;
    opacity: 0.9;
    margin-bottom: 15px;
    padding: 8px 18px;
    border: 1px solid rgba(255,255,255,0.4);
    border-radius: 30px;
    background: rgba(255,255,255,0.1);
}

.panel-title {
    font-size: 64px;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 6px;
    margin-bottom: 20px;
    line-height: 1;
}

.vocal-panel .panel-title {
    background: linear-gradient(90deg, #00e5ff, #00ffa3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.gaming-panel .panel-title {
    background: linear-gradient(90deg, #ff44ff, #ff8855);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.panel-description {
    font-size: 15px;
    line-height: 1.8;
    opacity: 0.9;
    margin-bottom: 30px;
}

.panel-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 15px 40px;
    border: 2px solid rgba(255,255,255,0.8);
    background: rgba(255,255,255,0.1);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    transition: all 0.3s ease;
    border-radius: 50px;
}

.vocal-panel:hover .panel-btn {
    background: #00e5ff;
    border-color: #00e5ff;
    color: #000;
}

.gaming-panel:hover .panel-btn {
    background: #ff44ff;
    border-color: #ff44ff;
    color: #000;
}

.tc-divider {
    width: 2px;
    background: linear-gradient(180deg, 
        transparent 0%, 
        rgba(255,255,255,0.3) 50%,
        transparent 100%);
}

/* ============================================
   Products Section
============================================ */
.tc-products-section {
    padding: 80px 30px;
    background: var(--tc-white);
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-title {
    font-size: 32px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 10px;
}

.section-subtitle {
    color: var(--tc-text-muted);
    font-size: 15px;
}

/* ============================================
   Products Grid
============================================ */
.tc-products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 350px));
    gap: 25px;
    max-width: 1200px;
    margin: 0 auto;
    justify-content: center;
}

.tc-product-card {
    background: var(--tc-white);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--tc-border);
    transition: box-shadow 0.3s ease, transform 0.3s ease;
    max-width: 350px;
    width: 100%;
}

.tc-product-card:hover {
    box-shadow: var(--tc-shadow-hover);
    transform: translateY(-5px);
}

.tc-product-card .product-category {
    padding: 15px 20px 0;
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
}

.tc-product-card.vocal .product-category {
    color: var(--tc-vocal-primary);
}

.tc-product-card.gaming .product-category {
    color: var(--tc-gaming-primary);
}

.tc-product-card .product-image {
    height: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: var(--tc-bg-light);
}

.tc-product-card .product-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.tc-product-card .product-image.no-image::after {
    content: '📦';
    font-size: 50px;
    opacity: 0.3;
}

.product-info {
    padding: 20px;
}

.product-name {
    font-size: 18px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 8px;
}

.product-desc {
    color: var(--tc-text-body);
    font-size: 14px;
    line-height: 1.6;
    margin-bottom: 12px;
}

.product-features {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.feature-tag {
    font-size: 11px;
    padding: 4px 10px;
    background: var(--tc-bg-gray);
    border-radius: 4px;
    color: var(--tc-text-muted);
}

.product-link {
    display: block;
    padding: 15px 20px;
    text-align: center;
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    border-top: 1px solid var(--tc-border-light);
    transition: background 0.3s ease;
}

.tc-product-card.vocal .product-link {
    color: var(--tc-vocal-primary);
}

.tc-product-card.vocal .product-link:hover {
    background: var(--tc-vocal-light);
}

.tc-product-card.gaming .product-link {
    color: var(--tc-gaming-primary);
}

.tc-product-card.gaming .product-link:hover {
    background: var(--tc-gaming-light);
}

/* ============================================
   Category Section
============================================ */
.tc-category-section {
    background: var(--tc-white);
}

.category-block {
    padding: 80px 30px;
}

.category-block.vocal {
    background: var(--tc-vocal-bg);
}

.category-block.gaming {
    background: var(--tc-gaming-bg);
}

.category-content {
    max-width: 1100px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.category-content.reverse {
    direction: rtl;
}

.category-content.reverse > * {
    direction: ltr;
}

.category-label {
    display: inline-block;
    font-size: 12px;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 12px;
    font-weight: 600;
}

.vocal .category-label {
    color: var(--tc-vocal-primary);
}

.gaming .category-label {
    color: var(--tc-gaming-primary);
}

.category-title {
    font-size: 36px;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 20px;
    color: var(--tc-text-dark);
}

.category-description {
    font-size: 15px;
    line-height: 1.8;
    color: var(--tc-text-body);
    margin-bottom: 25px;
}

.category-features {
    list-style: none;
    padding: 0;
    margin: 0 0 30px 0;
}

.category-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 0;
    font-size: 15px;
    color: var(--tc-text-body);
}

.category-features .icon {
    width: 22px;
    height: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-size: 12px;
    color: var(--tc-white);
}

.vocal .category-features .icon {
    background: var(--tc-vocal-primary);
}

.gaming .category-features .icon {
    background: var(--tc-gaming-primary);
}

.category-btn {
    display: inline-block;
    padding: 14px 35px;
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    border-radius: 6px;
    transition: background 0.3s ease;
    color: var(--tc-white);
}

.vocal-btn {
    background: var(--tc-vocal-primary);
}

.vocal-btn:hover {
    background: #007aa3;
}

.gaming-btn {
    background: var(--tc-gaming-primary);
}

.gaming-btn:hover {
    background: #7d3c98;
}

.category-image img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: var(--tc-shadow);
}

/* ============================================
   Features Section
============================================ */
.tc-features-section {
    padding: 80px 30px;
    background: var(--tc-bg-light);
}

.tc-features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
    max-width: 1100px;
    margin: 0 auto;
}

.feature-item {
    text-align: center;
    padding: 35px 25px;
    background: var(--tc-white);
    border-radius: 10px;
    box-shadow: var(--tc-shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--tc-shadow-hover);
}

.feature-icon {
    font-size: 40px;
    margin-bottom: 18px;
}

.feature-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 10px;
}

.feature-desc {
    color: var(--tc-text-muted);
    font-size: 13px;
    line-height: 1.6;
}

/* ============================================
   Support Section
============================================ */
.tc-support-section {
    padding: 80px 30px;
    background: var(--tc-white);
}

.tc-support-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    max-width: 1000px;
    margin: 0 auto;
}

.support-card {
    display: block;
    padding: 30px 20px;
    background: var(--tc-bg-light);
    border-radius: 10px;
    text-decoration: none;
    text-align: center;
    transition: background 0.3s ease, transform 0.3s ease;
}

.support-card:hover {
    background: var(--tc-bg-gray);
    transform: translateY(-3px);
}

.support-icon {
    font-size: 35px;
    margin-bottom: 15px;
}

.support-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 8px;
}

.support-desc {
    color: var(--tc-text-muted);
    font-size: 13px;
}

/* ============================================
   About TC Helicon Section
============================================ */
.tc-about-section {
    padding: 80px 30px;
    background: var(--tc-white);
}

.about-story {
    max-width: 1100px;
    margin: 0 auto 60px;
}

.about-story-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-heading {
    font-size: 28px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 20px;
}

.about-lead {
    font-size: 18px;
    font-weight: 500;
    color: var(--tc-text-dark);
    line-height: 1.7;
    margin-bottom: 20px;
}

.about-description {
    font-size: 15px;
    color: var(--tc-text-body);
    line-height: 1.8;
    margin-bottom: 15px;
}

.about-story-image img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: var(--tc-shadow);
}

.about-features {
    max-width: 1100px;
    margin: 0 auto 60px;
    padding: 50px 40px;
    background: var(--tc-bg-light);
    border-radius: 15px;
}

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

.about-feature-item {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.about-feature-icon {
    font-size: 36px;
}

.about-feature-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--tc-text-dark);
}

.about-feature-desc {
    font-size: 14px;
    color: var(--tc-text-body);
    line-height: 1.7;
}

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

.about-timeline-title {
    text-align: center;
    font-size: 24px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 40px;
}

.timeline-items {
    position: relative;
    padding-left: 30px;
}

.timeline-items::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(180deg, var(--tc-vocal-primary), var(--tc-gaming-primary));
    border-radius: 3px;
}

.timeline-item {
    position: relative;
    padding: 0 0 35px 30px;
}

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

.timeline-item::before {
    content: '';
    position: absolute;
    left: -36px;
    top: 5px;
    width: 15px;
    height: 15px;
    background: var(--tc-white);
    border: 3px solid var(--tc-vocal-primary);
    border-radius: 50%;
}

.timeline-item:nth-child(even)::before {
    border-color: var(--tc-gaming-primary);
}

.timeline-year {
    display: inline-block;
    font-size: 14px;
    font-weight: 700;
    color: var(--tc-vocal-primary);
    background: var(--tc-vocal-light);
    padding: 4px 12px;
    border-radius: 20px;
    margin-bottom: 10px;
}

.timeline-item:nth-child(even) .timeline-year {
    color: var(--tc-gaming-primary);
    background: var(--tc-gaming-light);
}

.timeline-content h4 {
    font-size: 17px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 5px;
}

.timeline-content p {
    font-size: 14px;
    color: var(--tc-text-body);
    line-height: 1.6;
}

/* ============================================
   Support CTA
============================================ */
.tc-support-cta {
    padding: 70px 30px;
    background: var(--tc-bg-light);
    text-align: center;
}

.tc-support-cta.gaming {
    background: var(--tc-bg-gray);
}

.support-cta-inner {
    max-width: 600px;
    margin: 0 auto;
}

.support-cta-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 10px;
}

.support-cta-desc {
    color: var(--tc-text-muted);
    font-size: 15px;
    margin-bottom: 30px;
}

.support-cta-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
}

.cta-btn {
    padding: 14px 30px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.cta-btn.primary {
    background: var(--tc-vocal-primary);
    color: #fff;
}

.tc-support-cta.gaming .cta-btn.primary {
    background: var(--tc-gaming-primary);
}

.cta-btn.primary:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.cta-btn.secondary {
    background: #fff;
    color: var(--tc-text-dark);
    border: 1px solid var(--tc-border);
}

.cta-btn.secondary:hover {
    background: var(--tc-bg-gray);
}

/* ============================================
   Category Page Hero
============================================ */
.tc-page-hero {
    position: relative;
    min-height: 50vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding-top: var(--total-nav-height);
}

.page-hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
}

.page-hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.vocal-hero .page-hero-overlay {
    background: linear-gradient(135deg, 
        rgba(30, 58, 95, 0.85) 0%, 
        rgba(42, 82, 152, 0.8) 50%, 
        rgba(61, 122, 184, 0.75) 100%);
}

.gaming-hero .page-hero-overlay {
    background: linear-gradient(135deg, 
        rgba(74, 44, 106, 0.85) 0%, 
        rgba(107, 63, 160, 0.8) 50%, 
        rgba(144, 85, 208, 0.75) 100%);
}

.tc-page-logo {
    position: absolute;
    top: calc(var(--total-nav-height) + 20px);
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
}

.tc-page-logo img {
    height: 45px;
    width: auto;
    filter: drop-shadow(0 2px 10px rgba(0, 0, 0, 0.3));
}

.page-hero-content {
    position: relative;
    z-index: 5;
    text-align: center;
    padding: 80px 30px 80px;
    color: #fff;
}

.page-hero-label {
    display: inline-block;
    font-size: 12px;
    letter-spacing: 3px;
    text-transform: uppercase;
    padding: 8px 20px;
    border: 1px solid rgba(255,255,255,0.4);
    border-radius: 30px;
    background: rgba(255,255,255,0.1);
    margin-bottom: 20px;
}

.page-hero-title {
    font-size: 48px;
    font-weight: 900;
    letter-spacing: 4px;
    margin-bottom: 15px;
}

.page-hero-description {
    font-size: 16px;
    line-height: 1.8;
    opacity: 0.9;
}

.category-tabs {
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    z-index: 10;
}

.category-tab {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 15px 35px;
    background: rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    transition: background 0.3s ease, color 0.3s ease;
    border-top: 3px solid transparent;
}

.category-tab:first-child {
    border-radius: 10px 0 0 0;
}

.category-tab:last-child {
    border-radius: 0 10px 0 0;
}

.category-tab:hover {
    background: rgba(255,255,255,0.15);
    color: #fff;
}

.category-tab.active {
    background: #fff;
    color: var(--tc-text-dark);
}

.vocal-hero .category-tab.active {
    border-top-color: var(--tc-vocal-primary);
}

.gaming-hero .category-tab.active {
    border-top-color: var(--tc-gaming-primary);
}

.tab-icon {
    font-size: 18px;
}

/* ============================================
   Product Navigation
============================================ */
.tc-product-nav {
    background: #fff;
    border-bottom: 1px solid var(--tc-border);
    position: sticky;
    top: var(--total-nav-height);
    z-index: 50;
}

.product-nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 30px;
    display: flex;
    gap: 10px;
    overflow-x: auto;
}

.product-nav-link {
    padding: 18px 25px;
    color: var(--tc-text-body);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    white-space: nowrap;
    border-bottom: 3px solid transparent;
    transition: color 0.3s ease, border-color 0.3s ease;
}

.product-nav-link:hover {
    color: var(--tc-text-dark);
    border-bottom-color: var(--tc-border);
}

/* ============================================
   Products List
============================================ */
.tc-products-list {
    background: #fff;
    padding: 60px 30px;
}

.product-category-block {
    max-width: 1200px;
    margin: 0 auto 60px;
}

.product-category-block:last-child {
    margin-bottom: 0;
}

.category-block-header {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--tc-border-light);
}

.category-block-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 8px;
}

.category-block-desc {
    color: var(--tc-text-muted);
    font-size: 14px;
}

/* ============================================
   Category Features Section
============================================ */
.tc-category-features {
    padding: 80px 30px;
}

.tc-category-features.vocal {
    background: var(--tc-vocal-bg);
}

.tc-category-features.gaming {
    background: var(--tc-gaming-bg);
}

.category-features-inner {
    max-width: 1100px;
    margin: 0 auto;
}

.category-features-title {
    text-align: center;
    font-size: 28px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 50px;
}

.features-grid-3col {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-box {
    background: #fff;
    padding: 35px 30px;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
}

.feature-box-icon {
    font-size: 40px;
    margin-bottom: 20px;
}

.feature-box-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 12px;
}

.feature-box-desc {
    font-size: 14px;
    line-height: 1.7;
    color: var(--tc-text-body);
}

/* ============================================
   Breadcrumb
============================================ */
.tc-breadcrumb {
    background: var(--tc-bg-light);
    padding: 15px 30px;
    font-size: 13px;
}

.breadcrumb-inner {
    max-width: 1200px;
    margin: 0 auto;
}

.tc-breadcrumb a {
    color: var(--tc-text-muted);
    text-decoration: none;
    transition: color 0.3s ease;
}

.tc-breadcrumb a:hover {
    color: var(--tc-vocal-primary);
}

.tc-breadcrumb .separator {
    margin: 0 10px;
    color: var(--tc-text-muted);
}

.tc-breadcrumb .current {
    color: var(--tc-text-dark);
    font-weight: 500;
}

/* ============================================
   Product Hero
============================================ */
.tc-product-hero {
    background: var(--tc-bg-light);
    padding: 40px 30px;
    text-align: center;
}

.product-hero-header {
    max-width: 800px;
    margin: 0 auto;
}

.brand-logo-hero {
    height: 40px;
    margin-bottom: 20px;
}

.product-logo {
    max-width: 400px;
    max-height: 80px;
    margin-bottom: 15px;
}

.product-title-hero {
    font-size: 36px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 10px;
}

.product-category-label {
    font-size: 14px;
    color: var(--tc-text-muted);
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* ============================================
   Category Tabs Bar
============================================ */
.category-tabs-bar {
    display: flex;
    justify-content: center;
    background: var(--tc-white);
    border-bottom: 1px solid var(--tc-border);
}

.category-tab-link {
    padding: 15px 40px;
    text-decoration: none;
    color: var(--tc-text-muted);
    font-weight: 500;
    font-size: 14px;
    border-bottom: 3px solid transparent;
    transition: color 0.3s ease, border-color 0.3s ease;
}

.category-tab-link:hover {
    color: var(--tc-text-dark);
}

.category-tab-link.active {
    color: var(--tc-vocal-primary);
    border-bottom-color: var(--tc-vocal-primary);
}

.category-tab-link .tab-icon {
    margin-right: 8px;
}

/* ============================================
   Product Detail
============================================ */
.tc-product-detail {
    padding: 60px 30px;
    background: var(--tc-white);
}

.tc-product-detail .container {
    max-width: 1200px;
    margin: 0 auto;
}

.product-showcase {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.product-gallery-wrapper {
    position: sticky;
    top: calc(var(--total-nav-height) + 20px);
}

.product-gallery .main-image {
    position: relative;
    background: var(--tc-bg-light);
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 15px;
    cursor: pointer;
}

.product-gallery .main-image img {
    width: 100%;
    height: auto;
    display: block;
}

.zoom-hint {
    position: absolute;
    bottom: 15px;
    right: 15px;
    font-size: 12px;
    color: var(--tc-text-muted);
    background: rgba(255,255,255,0.9);
    padding: 5px 10px;
    border-radius: 4px;
}

.thumbnail-images {
    display: flex;
    gap: 10px;
}

.thumbnail-images img {
    width: 80px;
    height: 80px;
    object-fit: cover;
    border-radius: 8px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: border-color 0.3s ease;
    background: var(--tc-bg-light);
    padding: 5px;
}

.thumbnail-images img:hover {
    border-color: var(--tc-border);
}

.thumbnail-images img.active {
    border-color: var(--tc-vocal-primary);
}

.product-info-detail {
    padding-top: 20px;
}

.product-info-header {
    margin-bottom: 20px;
}

.brand-logo-small {
    height: 30px;
}

.product-name-detail {
    font-size: 32px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 20px;
}

.product-description-lead {
    font-size: 18px;
    line-height: 1.7;
    color: var(--tc-text-dark);
    margin-bottom: 15px;
}

.product-description-body {
    font-size: 15px;
    line-height: 1.8;
    color: var(--tc-text-body);
    margin-bottom: 30px;
}

.key-features {
    background: var(--tc-bg-light);
    padding: 25px;
    border-radius: 12px;
    margin-bottom: 30px;
}

.key-features h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 15px;
}

.key-features ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.key-features li {
    position: relative;
    padding-left: 25px;
    padding-bottom: 10px;
    font-size: 14px;
    color: var(--tc-text-body);
    line-height: 1.6;
}

.key-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--tc-vocal-primary);
    font-weight: bold;
}

.product-dimensions {
    margin-bottom: 30px;
}

.product-dimensions h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--tc-text-dark);
    margin-bottom: 15px;
}

.dimensions-grid {
    display: flex;
    gap: 20px;
}

.dimension-item {
    text-align: center;
    padding: 15px 25px;
    background: var(--tc-bg-light);
    border-radius: 8px;
}

.dimension-value {
    font-size: 24px;
    font-weight: 700;
    color: var(--tc-text-dark);
}

.dimension-label {
    font-size: 12px;
    color: var(--tc-text-muted);
    margin-top: 5px;
}

.product-cta {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.btn-tc {
    display: inline-block;
    padding: 14px 30px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    text-align: center;
    transition: background 0.3s ease, opacity 0.3s ease;
}

.btn-tc.btn-primary {
    background: var(--tc-vocal-primary);
    color: var(--tc-white);
}

.btn-tc.btn-primary:hover {
    background: #007aa3;
}

.btn-tc.btn-secondary {
    background: var(--tc-white);
    color: var(--tc-text-dark);
    border: 1px solid var(--tc-border);
}

.btn-tc.btn-secondary:hover {
    background: var(--tc-bg-light);
}

/* ============================================
   About Product Section
============================================ */
.tc-about-product {
    padding: 80px 30px;
    background: var(--tc-white);
}

.tc-about-product .container {
    max-width: 900px;
    margin: 0 auto;
}

.about-product-content {
    margin-top: 40px;
}

.about-section {
    margin-bottom: 40px;
    padding: 30px;
    background: var(--tc-bg-light);
    border-radius: 12px;
    border-left: 4px solid var(--tc-vocal-primary);
}

.about-section h3 {
    font-size: 20px;
    font-weight: 700;
    color: var(--tc-text-dark);
    margin-bottom: 15px;
}

.about-section p {
    font-size: 15px;
    line-height: 1.9;
    color: var(--tc-text-dark);
}

/* ============================================
   Specs Section
============================================ */
.tc-specs-section {
    padding: 80px 30px;
    background: var(--tc-white);
}

.tc-specs-section .container {
    max-width: 900px;
    margin: 0 auto;
}

.specs-container {
    margin-top: 40px;
}

.specs-table {
    width: 100%;
    border-collapse: collapse;
}

.specs-table th {
    background: var(--tc-vocal-primary);
    color: var(--tc-white);
    padding: 15px 20px;
    text-align: left;
    font-size: 16px;
    font-weight: 600;
}

.specs-table td {
    padding: 15px 20px;
    border-bottom: 1px solid var(--tc-border);
    font-size: 14px;
    color: var(--tc-text-body);
}

.specs-table tr:nth-child(even) {
    background: var(--tc-bg-light);
}

.specs-table td:first-child {
    font-weight: 500;
    color: var(--tc-text-dark);
    width: 40%;
}

/* ============================================
   Video Section
============================================ */
.tc-video-section {
    padding: 80px 30px;
    background: var(--tc-bg-light);
}

.tc-video-section .container {
    max-width: 1000px;
    margin: 0 auto;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 12px;
    background: #000;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.video-title {
    margin-top: 10px;
    font-size: 14px;
    color: var(--tc-text-body);
    text-align: center;
}

/* ============================================
   Downloads Section
============================================ */
.tc-downloads-section {
    padding: 60px 30px;
    background: var(--tc-white);
}

.tc-downloads-section .container {
    max-width: 800px;
    margin: 0 auto;
}

.downloads-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-top: 30px;
    justify-content: center;
}

.download-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 15px 25px;
    background: var(--tc-bg-light);
    border-radius: 8px;
    text-decoration: none;
    color: var(--tc-text-dark);
    font-size: 14px;
    font-weight: 500;
    transition: background 0.3s ease, transform 0.3s ease;
}

.download-item:hover {
    background: var(--tc-bg-gray);
    transform: translateY(-2px);
}

.download-icon {
    font-size: 20px;
}

/* ============================================
   Related Section
============================================ */
.tc-related-section {
    padding: 80px 30px;
    background: var(--tc-bg-light);
}

.tc-related-section .container {
    max-width: 1200px;
    margin: 0 auto;
}

.tc-related-section .tc-products-grid {
    margin-top: 40px;
}

/* ============================================
   Lightbox
============================================ */
.lightbox {
    display: none;
    position: fixed;
    z-index: 9999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.95);
    cursor: pointer;
}

.lightbox-close {
    position: absolute;
    top: 20px;
    right: 30px;
    color: #fff;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    z-index: 10000;
}

.lightbox-content {
    display: block;
    max-width: 90%;
    max-height: 85%;
    margin: auto;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.lightbox-caption {
    color: #fff;
    text-align: center;
    padding: 15px;
    position: absolute;
    bottom: 20px;
    width: 100%;
    font-size: 16px;
}

/* ============================================
   CTAボタン（購入・マニュアル）
============================================ */
.product-cta-buttons {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 25px;
    padding-top: 25px;
    border-top: 1px solid #eee;
}

.btn-cta {
    flex: 1 1 auto;
    min-width: 140px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 12px 14px;
    border-radius: 8px;
    text-decoration: none;
    font-size: 13px;
    font-weight: 600;
    transition: all 0.2s ease;
    text-align: center;
    white-space: nowrap;
}

.btn-cta .btn-icon {
    font-size: 15px;
}

.btn-buy {
    background: #1a1a2e;
    color: #fff;
    border: 2px solid #1a1a2e;
}

.btn-buy:hover {
    background: #2d2d44;
    border-color: #2d2d44;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 26, 46, 0.3);
}

.btn-manual {
    background: #fff;
    color: #333;
    border: 2px solid #ddd;
}

.btn-manual:hover {
    border-color: #1a1a2e;
    color: #1a1a2e;
    background: #f5f5f7;
}

/* ============================================
   ソフトウェアダウンロードリンク
============================================ */
.software-download-link {
    margin-top: 15px;
    text-align: center;
}

.software-download-link a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    font-size: 13px;
    color: #666;
    text-decoration: none;
    border-radius: 6px;
    transition: all 0.2s ease;
    background: #f5f5f5;
}

.software-download-link a:hover {
    color: #1a1a2e;
    background: #eaeaea;
}

.software-download-link .dl-icon {
    font-size: 16px;
}

.software-download-link .external-icon {
    font-size: 12px;
    opacity: 0.6;
}

/* ============================================
   Gaming Theme Styles
============================================ */
.tc-product-hero.gaming {
    background: var(--tc-gaming-bg);
}

.category-tab-link.active.gaming {
    color: var(--tc-gaming-primary);
    border-bottom-color: var(--tc-gaming-primary);
}

.key-features.gaming {
    background: var(--tc-gaming-light);
}

.key-features.gaming li::before {
    color: var(--tc-gaming-primary);
}

.product-info-detail.gaming .thumbnail-images img.active {
    border-color: var(--tc-gaming-primary);
}

.btn-tc.btn-primary.gaming {
    background: var(--tc-gaming-primary);
}

.btn-tc.btn-primary.gaming:hover {
    background: #7d3c98;
}

.about-section.gaming {
    border-left-color: var(--tc-gaming-primary);
}

.specs-table.gaming th {
    background: var(--tc-gaming-primary);
}

.download-item.gaming:hover {
    background: var(--tc-gaming-light);
}

.tc-support-cta.gaming {
    background: var(--tc-gaming-bg);
}

.tc-support-cta.gaming .cta-btn.primary.gaming {
    background: var(--tc-gaming-primary);
}

.tc-support-cta.gaming .cta-btn.primary.gaming:hover {
    background: #7d3c98;
}

.gaming .btn-buy {
    background: #9c27b0;
    border-color: #9c27b0;
}

.gaming .btn-buy:hover {
    background: #7b1fa2;
    border-color: #7b1fa2;
    box-shadow: 0 4px 12px rgba(156, 39, 176, 0.3);
}

.gaming .btn-manual:hover {
    border-color: #9c27b0;
    color: #9c27b0;
}

/* ============================================
   Responsive Design
============================================ */
@media (max-width: 1024px) {
    .tc-features-grid,
    .tc-support-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .category-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .category-content.reverse {
        direction: ltr;
    }
    
    .category-image {
        order: -1;
    }
}

@media (max-width: 992px) {
    .product-showcase {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .product-gallery-wrapper {
        position: static;
    }
}

@media (max-width: 768px) {
    /* CSS変数を上書き（共通ヘッダーは64pxのまま） */
    :root {
        --header-height: 64px;
        --brand-nav-height: 40px;
        --total-nav-height: 104px;
    }
    
    /* ブランドナビ */
    .tc-helicon-brand-nav {
        padding: 10px 0;
    }
    
    .tc-helicon-brand-nav .brand-nav-container {
        padding: 0 15px;
    }
    
    .tc-helicon-brand-nav .brand-nav-links {
        gap: 12px;
    }
    
    .tc-helicon-brand-nav .brand-nav-links li a {
        font-size: 11px;
    }
    
    /* Hero */
    .tc-hero-split {
        flex-direction: column;
    }
    
    .tc-hero-logo {
        top: calc(var(--total-nav-height) + 20px);
    }
    
    .tc-hero-logo img {
        height: 50px;
    }
    
    .tc-category-panel {
        min-height: 50vh;
    }
    
    .tc-category-panel:hover {
        flex: 1;
    }
    
    .tc-divider {
        width: 100%;
        height: 2px;
    }
    
    .panel-title {
        font-size: 42px;
    }
    
    .panel-content {
        margin-top: 30px;
    }
    
    /* Page Hero */
    .tc-page-logo {
        top: calc(var(--total-nav-height) + 10px);
    }
    
    .tc-page-logo img {
        height: 35px;
    }
    
    .page-hero-title {
        font-size: 32px;
    }
    
    .page-hero-content {
        padding: 70px 20px 60px;
    }
    
    .category-tabs {
        width: 100%;
        left: 0;
        transform: none;
    }
    
    .category-tab {
        flex: 1;
        justify-content: center;
        padding: 12px 20px;
        border-radius: 0;
    }
    
    /* Sections */
    .tc-products-section,
    .tc-features-section,
    .tc-support-section,
    .category-block {
        padding: 60px 20px;
    }
    
    .tc-products-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 26px;
    }
    
    .category-title {
        font-size: 28px;
    }
    
    /* About */
    .about-story-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .about-story-image {
        order: -1;
    }
    
    .about-heading {
        font-size: 24px;
    }
    
    .about-lead {
        font-size: 16px;
    }
    
    .about-features-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .about-features {
        padding: 30px 25px;
    }
    
    .timeline-items {
        padding-left: 20px;
    }
    
    .timeline-item {
        padding-left: 25px;
    }
    
    .timeline-item::before {
        left: -27px;
        width: 12px;
        height: 12px;
    }
    
    /* Features */
    .features-grid-3col {
        grid-template-columns: 1fr;
    }
    
    /* Support CTA */
    .support-cta-buttons {
        flex-direction: column;
    }
    
    /* Product Detail */
    .product-name-detail {
        font-size: 26px;
    }
    
    .product-description-lead {
        font-size: 16px;
    }
    
    .dimensions-grid {
        flex-wrap: wrap;
    }
    
    .dimension-item {
        flex: 1;
        min-width: 80px;
    }
    
    .product-cta {
        flex-direction: column;
    }
    
    .btn-tc {
        width: 100%;
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .category-tab-link {
        padding: 12px 25px;
        font-size: 13px;
    }
    
    /* CTA Buttons */
    .product-cta-buttons {
        flex-direction: column;
    }
    
    .btn-cta {
        width: 100%;
        min-width: unset;
    }
}

@media (max-width: 480px) {
    /* CSS変数を上書き */
    :root {
        --header-height: 64px;
        --brand-nav-height: 35px;
        --total-nav-height: 99px;
    }
    
    /* ブランドナビ */
    .tc-helicon-brand-nav {
        padding: 8px 0;
    }
    
    .tc-helicon-brand-nav .brand-nav-links {
        gap: 8px;
    }
    
    .tc-helicon-brand-nav .brand-nav-links li a {
        font-size: 10px;
    }
    
    /* Hero */
    .tc-hero-logo {
        top: calc(var(--total-nav-height) + 15px);
    }
    
    .tc-hero-logo img {
        height: 40px;
    }
    
    .panel-title {
        font-size: 32px;
    }
    
    .panel-btn {
        padding: 12px 30px;
        font-size: 12px;
    }
    
    .panel-content {
        margin-top: 20px;
        padding: 30px 20px;
    }
    
    /* Features & Support */
    .tc-features-grid,
    .tc-support-grid {
        grid-template-columns: 1fr;
    }
}