/* ==========================================================================
   Variables
   ========================================================================== */
:root {
    --main-color: #00a4b3;
    --main-color-light: #00a4b326;
    --main-color-border: #00a4b366;
}

/* ==========================================================================
   Base Styles
   ========================================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: var(--main-color) url('images/background.svg') no-repeat center/cover;
    background-blend-mode: multiply;
    opacity: 0.2;
}

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

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
header {
    background: #FFFFFFF2;
    border-bottom: 2px solid var(--main-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.logo img {
    height: 50px;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li a {
    text-decoration: none;
    color: #333;
    padding: 10px 15px;
    font-weight: bold;
    display: block;
    transition: color 0.3s;
}

nav ul li a:hover {
    color: var(--main-color);
}

.menu-icon {
    display: none;
    cursor: pointer;
    width: 30px;
    height: 25px;
    position: relative;
    z-index: 1001;
}

/* ==========================================================================
   Hero Section (Top Page)
   memo
   linear-gradient(to right, #0000004D 0%, #0000001A 40%, #00000000 100%), 
   ========================================================================== */
.hero {
    position: relative;
    background: url('images/01_風布の滝.webp') no-repeat center center/cover;
    height: 100vh;
    display: flex;
    align-items: center; 
    justify-content: center;
    color: #fff;
    padding: 0;
}

.hero-content {
    max-width: 1300px;
    padding: 0 60px;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.hero-main-text {
    font-size: clamp(24px, 2.2vw, 40px);
    font-weight: 700;
    line-height: 1.4;
    margin-bottom: 40px;
    letter-spacing: 0.05em;
    text-shadow: 0 0 20px #000000E6, 0 2px 4px #000000B3;
}

.hero-sub-group {
    margin-left: 1vw;
}

.hero-english {
    font-size: clamp(24px, 1.1vw, 40px);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.3em;
    color: var(--main-color);
    margin-bottom: 8px;
    display: block;
    text-shadow: 0 0 5px #000;
}

.hero-sub-text {
    line-height: 1.8;
    color: #fff;
    text-shadow: 0 0 15px #000000E6, 0 0 5px #000000FF;
	margin-left: -0.4rem;
}

/* ==========================================================================
   Products Section (Top Page)
   ========================================================================== */
.products {
    padding: 60px 0;
}

.products h2 {
    text-align: center;
    color: var(--main-color);
    margin-bottom: 40px;
    font-size: 2rem;
}

.products-lead-container {
    text-align: center;
    background: #f4fbfc;
    padding: 40px 20px;
    margin-bottom: 80px;
    border-left: 5px solid var(--main-color);
    border-right: 5px solid var(--main-color);
}

.products-lead-container p {
    font-size: 1.1rem;
    font-weight: 500;
    line-height: 1.8;
    color: #444;
}

.product-item {
    display: flex;
    align-items: center;
    margin-bottom: 80px;
    gap: 5%;
}

.product-item.reverse {
    flex-direction: row-reverse;
}

.product-text, .product-img, .product-img-special {
    flex: 1;
}

.product-text h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
}

.product-text h3 a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s;
}

.product-text h3 a:hover {
    color: var(--main-color);
}

.detail-link {
    display: inline-block;
    margin-top: 15px;
    padding: 8px 20px;
    background: var(--main-color);
    color: #fff;
    text-decoration: none;
    font-size: 0.9rem;
    border-radius: 4px;
    transition: opacity 0.3s;
}

.detail-link:hover {
    opacity: 0.8;
}

.product-img-special {
    position: relative;
    max-width: 450px;
}

.img-overlay {
    position: absolute;
    bottom: -15px;
    right: -15px;
    width: 55% !important;
    border: 3px solid #fff;
    box-shadow: 0 4px 15px #0000004D;
}

/* ==========================================================================
   Contact Section
   ========================================================================== */
.contact {
    padding: 100px 0;
    position: relative;
}

.contact::before, .contact::after {
    content: "";
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 50%;
    height: 1px;
    background: var(--main-color-border); 
}
.contact::before { top: 0; }
.contact::after { bottom: 0; }

.contact-inner {
    max-width: 900px;
    margin: 0 auto;
    background: #FFFFFF66;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid #FFFFFF99;
    border-radius: 20px;
    padding: 60px 40px;
    box-shadow: 0 20px 40px #0000000D;
}

.contact-header {
    margin-bottom: 40px;
    text-align: center;
}

.contact-sub-title {
    display: block;
    font-size: 0.85rem;
    color: var(--main-color);
    letter-spacing: 0.5em;
    margin-bottom: 8px;
    font-weight: 700;
}

.contact h2 {
    font-size: 1.8rem;
    color: #333;
}

.contact-lead {
    text-align: center;
    margin-bottom: 50px;
    color: #555;
    font-size: 1rem;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2px;
    background: var(--main-color-light); 
    max-width: 800px;
    margin: 0 auto;
}

.contact-card {
    background: #FFFFFF80; 
    padding: 30px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.contact-type {
    font-size: 0.75rem;
    color: var(--main-color);
    font-weight: 700;
    margin-bottom: 15px;
    letter-spacing: 0.1em;
}

.contact-val {
    font-size: 1.5rem;
    font-weight: 500;
    color: #333;
    text-decoration: none;
    transition: all 0.3s ease;
}

.email .contact-val:hover {
    color: var(--main-color);
}

.contact-val.fax {
    font-size: 1rem;
    color: #777;
    margin-top: 5px;
}

/* ==========================================================================
   Footer
   ========================================================================== */
footer {
    background: var(--main-color);
    color: #fff;
    padding: 60px 0 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 40px;
    padding-bottom: 40px;
}

.footer-logo img {
    height: 40px;
    filter: brightness(0) invert(1);
    margin-bottom: 20px;
}

.footer-nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.footer-nav ul li a {
    color: #fff;
    text-decoration: none;
    font-size: 0.95rem;
    transition: opacity 0.3s;
}

.footer-nav ul li a:hover {
    color: #e0f7f8;
    opacity: 0.7;
    text-decoration: underline;
}

.footer-bottom {
    border-top: 1px solid #FFFFFF33;
    padding: 20px 0;
    text-align: center;
}

.copyright {
    font-size: 0.85rem;
    margin: 0;
}

/* ==========================================================================
   Responsive Design (Mobile)
   ========================================================================== */
@media (max-width: 768px) {
    #nav-menu {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: #fff;
        border-bottom: 2px solid var(--main-color);
    }

    #nav-menu.active {
        display: block;
    }

    #nav-menu ul {
        flex-direction: column;
        padding: 20px 0;
    }

    .menu-icon {
        display: block;
    }

    .menu-icon span {
        display: block;
        height: 3px;
        background: var(--main-color);
        margin-bottom: 6px;
        transition: 0.3s;
    }

    .menu-icon.active span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
    .menu-icon.active span:nth-child(2) { opacity: 0; }
    .menu-icon.active span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

    .product-item, .product-item.reverse {
        flex-direction: column;
        gap: 30px;
    }

    .hero-content {
        padding: 0 25px;
    }
    .hero-main-text {
        font-size: 1.6rem;
        margin-bottom: 30px;
    }
    .hero-english { font-size: 1rem; }
    .hero-sub-text { font-size: 0.95rem; }

    .product-img-special {
        max-width: 100%;
        padding-right: 15px;
    }
    .img-overlay {
        right: 0;
        bottom: -15px;
        width: 50%;
    }

    .contact { padding: 60px 20px; }
    .contact-inner { padding: 40px 20px; }
    .contact-grid {
        grid-template-columns: 1fr;
        background: none;
        gap: 20px;
    }
    .contact-card {
        background: #FFFFFF4D;
        border-radius: 12px;
    }
    .contact-val { font-size: 1.25rem; }

    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 30px;
        padding-bottom: 30px;
    }

    .footer-nav ul {
        flex-direction: column;
        align-items: center;
        gap: 15px;
    }

    .sub-hero { 
        height: 200px; 
        min-height: auto; /* モバイルでは高さ固定を優先 */
    }
    .sub-hero h1 { 
        font-size: 1.8rem; 
    }
}

/* ==========================================================================
   Common Elements for Lower Pages
   ========================================================================== */
.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title .eng {
    display: block;
    font-size: 0.9rem;
    color: var(--main-color);
    letter-spacing: 0.3em;
    font-weight: 700;
    margin-bottom: 5px;
}

.section-title h2 {
    font-size: 1.8rem;
    position: relative;
    display: inline-block;
    padding-bottom: 15px;
}

/* 下層ページ共通ヒーロー（統合・修正版） */
.sub-hero {
    position: relative;
    background: url('images/01_風布の滝.webp') no-repeat center center/cover;
    height: 50vh;
    min-height: 300px;
    display: flex;
    align-items: center;
    color: #fff;
    margin-bottom: 80px;
    mask-image: linear-gradient(to bottom, black 70%, transparent 100%);
    -webkit-mask-image: linear-gradient(to bottom, black 60%, transparent 100%);
    z-index: 2;
}

.sub-hero::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--main-color);
    opacity: 0.15;
    z-index: 1;
}

.sub-hero .container {
    position: relative;
    z-index: 2;
}

.sub-hero h1 {
    font-size: 3rem;
    letter-spacing: 0.15em;
    font-weight: 700;
    text-shadow: 0 0 15px #00000080;
}

.sub-hero h1 span {
    display: block;
    font-size: 1.1rem;
    font-weight: 500;
    margin-top: 5px;
    color: #fff;
    opacity: 0.9;
    letter-spacing: 0.3em;
}