:root {
    --primary-color: #0D47A1; /* 深い青 */
    --secondary-color: #1976D2; /* 明るめの青 */
    --surface-color: #ECEFF1; /* 薄い青灰色 */
    --text-color: #333;
    --heading-font: 'Noto Sans JP', sans-serif;
    --body-font: 'Noto Sans JP', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

html {
    box-sizing: border-box;
    font-size: 100%;
    scroll-behavior: smooth;
}

*, *::before, *::after {
    box-sizing: inherit;
}

body {
    font-family: var(--body-font);
    font-size: 16px; /*基準フォントサイズを指定*/
    line-height: 1.8;
    margin: 0;
    padding: 0;
    background: #fff;
    color: var(--text-color);
}

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

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 900;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
}

.btn {
    display: inline-block;
    padding: 14px 28px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
    border: 2px solid transparent;
}

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

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

.btn.line {
    background: #00B900;
    border-color: #00B900;
    color: #fff;
}

.btn.line:hover {
    background: #fff;
    color: #00B900;
}


.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(10px);
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.brand__logo {
    max-width: 240px; /* PCでのロゴサイズ調整 */
    transition: all 0.3s ease;
}

.nav__list {
    display: flex;
    align-items: center;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav__list li:not(:last-child) {
    margin-right: 2rem;
}

.nav__list a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 600;
    position: relative;
    padding-bottom: 5px;
}

.nav__list a:not(.btn)::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.nav__list a:not(.btn):hover::after {
    width: 100%;
}

.nav-toggle {
    display: none; /* PCでは非表示 */
    width: 30px;
    height: 22px;
    position: relative;
    cursor: pointer;
    background: transparent;
    border: none;
    z-index: 110;
}

.nav-toggle span {
    display: block;
    position: absolute;
    width: 100%;
    height: 3px;
    background-color: var(--text-color);
    border-radius: 3px;
    transition: all 0.3s ease-in-out;
}

.nav-toggle span:nth-child(1) { top: 0; }
.nav-toggle span:nth-child(2) { top: 50%; transform: translateY(-50%); }
.nav-toggle span:nth-child(3) { bottom: 0; }


.hero {
    padding-top: 150px;
    padding-bottom: 100px;
    background: linear-gradient(45deg, #0D47A1, #42A5F5); /* 青系のグラデーション */
    color: #fff;
    position: relative;
    z-index: 1;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url(img/7.png);
    background-size: cover;
    background-position: center;
    opacity: 0.1;
    z-index: -1;
}

.hero__grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    align-items: center;
    gap: 3rem;
}

.hero__title {
    font-size: 3.2rem;
    font-weight: 900;
    margin-bottom: 1.5rem;
    line-height: 1.4;
    text-shadow: 1px 1px 3px rgba(0,0,0,0.2);
}

.hero__title .accent {
    color: #FFEB3B; /* 黄色でアクセント */
}

.lead {
    font-size: 1.1rem;
}

.hero__image img {
    width: 100%;
    border-radius: 15px;
}

.surface-muted {
    background: var(--surface-color);
}

.card {
    background: #fff;
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.07);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    height: 100%;
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.1);
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.card p {
    flex-grow: 1;
    word-break: break-word;
}

.grid-3, .grid-4 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.price {
    font-size: 2.5rem;
    font-weight: 900;
    color: var(--primary-color);
}

.tax {
    font-size: 1rem;
    margin-left: 5px;
}

.site-footer {
    background: #263238; /* 濃い青灰色 */
    color: #fff;
    padding: 60px 0 20px;
}

#contact {
    padding: 0;
    margin-bottom: 4rem;
}

.contact-card {
    background: rgba(255,255,255,0.1);
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
}

.contact-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.copyright {
    text-align: center;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.2);
}

.profile-section {
    display: flex;
    align-items: center;
    gap: 3rem;
    background: var(--surface-color);
    padding: 4rem;
    border-radius: 15px;
}

.profile-img {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid #fff;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

:target {
    scroll-margin-top: 90px;
}

/* Responsive */
@media (max-width: 1200px) {
    .nav-toggle { display: block; }
    .nav {
        display: block;
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: #fff;
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        transform: translateY(-150%);
        transition: transform 0.3s ease-in-out;
        z-index: 99;
    }
    .nav.nav--visible {
        transform: translateY(0);
    }
    .nav__list {
        flex-direction: column;
        align-items: stretch;
        padding: 1rem 0;
    }
    .nav__list li {
        margin: 0;
    }
    .nav__list a {
        display: block;
        padding: 1rem 2rem;
        border-bottom: 1px solid #f0f0f0;
    }
    .nav__list a:hover {
        background: #f9f9f9;
    }
    .nav__list a::after {
        display: none;
    }

    .hero__grid { grid-template-columns: 1fr; text-align: center; }
    .profile-section { flex-direction: column; text-align: center; }
}

@media (max-width: 767px) {
    .brand__logo { max-width: 180px; } /* スマホでのロゴサイズ調整 */
    .section { padding: 60px 0; }
    .hero { padding-top: 120px; padding-bottom: 60px; }
    .hero__title { font-size: 2.5rem; }
    .card { padding: 1.5rem; }
}

@media (max-width: 360px) {
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* Problem list */
#problem .container { 
  text-align: initial !important;
}

#problem .section-header { 
  text-align: center;
}

#problem .problem-list{
  list-style: none;
  margin: 0 auto;
  padding: 0 1rem;
  max-width: 42rem;
  display: block;
  text-align: left;
}

#problem .problem-list li{
  position: relative;
  display: block;
  padding-left: 1.5rem;
  margin: .5rem 0;
  line-height: 1.7;
  word-break: break-word;
  background: none !important;
}

#problem .problem-list li::before{
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 0; 
  height: 0;
  border-style: solid;
  border-width: 6px 0 6px 9px;
  border-color: transparent transparent transparent var(--primary-color);
  margin: 0;
}

#problem .problem-lead{
  margin-top: 1.5rem;
  font-weight: 700;
  font-size: 1.2rem;
  text-align: center;
}

@media (max-width: 767px){
  #problem .problem-list{ padding: 0 1rem; }
  #problem .problem-list li{ font-size: .95rem; }
}

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s, transform 0.5s;
}

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

.footer-logo {
    text-align: center;
    margin-bottom: 2rem;
}

.footer-logo img {
    max-width: 300px;
}