:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1d4ed8;
    --color-secondary: #f97316;
    --color-background: #f4f7fb;
    --color-surface: #ffffff;
    --color-border: rgba(15, 23, 42, 0.1);
    --color-muted: #64748b;
    --color-text: #1f2937;
    --radius-sm: 10px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --shadow-sm: 0 6px 18px rgba(15, 23, 42, 0.06);
    --shadow-md: 0 16px 35px rgba(15, 23, 42, 0.12);
    --max-width: min(100%, 960px);
    --font-base: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Segoe UI", sans-serif;
    --font-size-base: clamp(0.95rem, calc(0.9rem + 0.3vw), 1rem);
    --font-size-md: clamp(1rem, calc(0.95rem + 0.35vw), 1.1rem);
    --font-size-sm: clamp(0.85rem, calc(0.8rem + 0.3vw), 0.95rem);
    --font-size-xs: clamp(0.75rem, calc(0.7rem + 0.25vw), 0.85rem);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: var(--font-base);
    font-size: var(--font-size-base);
    line-height: 1.75;
    color: var(--color-text);
    background: radial-gradient(120% 120% at 50% 0%, rgba(59, 130, 246, 0.12) 0%, rgba(59, 130, 246, 0) 55%),
                var(--color-background);
}

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

a {
    color: var(--color-primary);
}

a:hover {
    color: var(--color-primary-dark);
}

main {
    padding-inline: clamp(1.2rem, 3vw, 1.8rem);
    padding-block: clamp(1.2rem, 3vw, 2.4rem);
}

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

.site-header {
    padding: 1.6rem clamp(1.2rem, 4vw, 3rem) 2.8rem;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.95), rgba(29, 78, 216, 0.9));
    color: #fff;
    border-bottom-left-radius: var(--radius-lg);
    border-bottom-right-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

.header-icon {
  width: 24px;
  height: 24px;
  margin-right: 6px;
  vertical-align: middle;
}

.site-header::before {
    content: "";
    position: absolute;
    inset: -30% 40% auto -20%;
    height: 320px;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.22) 0%, rgba(255, 255, 255, 0) 70%);
    pointer-events: none;
    opacity: 0.6;
}

.site-header h1 {
    margin: 0;
    font-size: clamp(1.8rem, 5vw, 2.6rem);
    font-weight: 700;
    letter-spacing: 0.02em;
}

.site-header p {
    margin: 0.6rem 0 0;
    font-size: clamp(0.95rem, 2.5vw, 1.05rem);
    opacity: 0.85;
}

.site-header .header-actions {
    margin-top: 1.6rem;
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.site-header .header-action {
    padding: 0.65rem 1.2rem;
    border-radius: 999px;
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text);
    background: rgba(255, 255, 255, 0.92);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    box-shadow: 0 4px 15px rgba(15, 23, 42, 0.12);
}

.site-header .header-action svg {
    width: 18px;
    height: 18px;
}

.site-header .header-action:hover {
    transform: translateY(-2px);
}

.section-header {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    margin-bottom: 1.4rem;
}

.section-header h2 {
    font-size: clamp(1.3rem, 4vw, 1.75rem);
    margin: 0;
    color: var(--color-text);
}

.section-header p {
    margin: 0;
    color: var(--color-muted);
    font-size: var(--font-size-sm);
}


.support-hero {
    margin-top: clamp(-2.4rem, -5vw, -1.8rem);
    display: grid;
    gap: clamp(1.2rem, 4vw, 1.8rem);
}

.hero-intro {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border);
    padding: clamp(1.4rem, 4vw, 2rem);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
}

.hero-intro::after {
    content: "";
    position: absolute;
    inset: auto -35% -35% auto;
    width: clamp(160px, 55vw, 260px);
    aspect-ratio: 1/1;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.18) 0%, rgba(59, 130, 246, 0) 70%);
    pointer-events: none;
}

.hero-intro h2 {
    margin: 0;
    font-size: clamp(1.4rem, 4vw, 1.9rem);
}

.hero-intro p {
    margin: 0.6rem 0 0;
    color: var(--color-muted);
}

.quick-links {
    display: grid;
    gap: 0.8rem;
    margin-top: clamp(1rem, 3vw, 1.4rem);
}

.quick-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(255, 255, 255, 0.9);
    border-radius: var(--radius-md);
    padding: 1rem 1.2rem;
    border: 1px solid rgba(15, 23, 42, 0.1);
    text-decoration: none;
    color: var(--color-text);
    font-weight: 600;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.quick-link span {
    display: inline-flex;
    align-items: center;
    gap: 0.6rem;
}

.quick-link svg {
    width: 20px;
    height: 20px;
}

.quick-link:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-md);
    color: var(--color-primary);
}

.category-section {
    margin-top: clamp(2rem, 5vw, 3rem);
}

.categories {
    display: grid;
    gap: clamp(0.9rem, 3vw, 1.4rem);
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.category-card {
    background: var(--color-surface);
    padding: clamp(1.1rem, 3vw, 1.6rem);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    gap: 0.65rem;
    min-height: 160px;
    box-shadow: var(--shadow-sm);
    position: relative;
    isolation: isolate;
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.category-card::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08), transparent);
    opacity: 0;
    transition: opacity 0.25s ease;
    z-index: -1;
}

.category-card h3 {
    margin: 0;
    font-size: var(--font-size-md);
    color: var(--color-primary);
}

.category-card p {
    margin: 0;
    color: var(--color-muted);
    font-size: var(--font-size-sm);
}

.category-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.category-card:hover::after {
    opacity: 1;
}

.top-faq-section {
    margin-top: clamp(2.5rem, 6vw, 3.2rem);
}

.top-faq-section ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 0.75rem;
}

.top-faq-section li a {
    display: block;
    text-decoration: none;
    background: var(--color-surface);
    padding: 1rem 1.1rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    color: var(--color-text);
    font-weight: 600;
    font-size: var(--font-size-base);
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.top-faq-section li a:hover {
    transform: translateX(3px);
    box-shadow: var(--shadow-md);
    color: var(--color-primary);
}

.site-footer {
    margin-top: clamp(2.5rem, 6vw, 3.5rem);
    padding: 1.8rem clamp(1.2rem, 4vw, 2rem);
    text-align: center;
    font-size: var(--font-size-xs);
    color: var(--color-muted);
    background: rgba(255, 255, 255, 0.65);
    border-top: 1px solid rgba(15, 23, 42, 0.05);
}

.emphasis-red {
    color: #ef4444;
    font-weight: 700;
}

.support-text-box {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: clamp(1.1rem, 3vw, 1.6rem);
    box-shadow: var(--shadow-sm);
}

.support-text-box h3 {
    margin-top: 0;
}

.faq-list-section h2,
.top-faq-section h2,
.category-section h2,
.article-content h2 {
    font-size: clamp(1.2rem, 4vw, 1.6rem);
    margin: 0 0 0.8rem;
    color: var(--color-text);
}

.article-content h3 {
    font-size: clamp(1.05rem, 3vw, 1.35rem);
    margin-top: 1.8rem;
    margin-bottom: 0.6rem;
    padding-left: 0.8rem;
    border-left: 4px solid var(--color-primary);
}

.article-content p {
    margin: 0 0 1rem;
    color: var(--color-muted);
}

.breadcrumbs {
    font-size: var(--font-size-xs);
    color: var(--color-muted);
    margin-bottom: 1.2rem;
}

.breadcrumbs a {
    color: var(--color-primary);
    font-weight: 600;
    text-decoration: none;
}

.breadcrumbs a:hover {
    text-decoration: underline;
}

.contact-form-section,
.cannot-resolve-section,
.card-section {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    padding: clamp(1.2rem, 3vw, 1.8rem);
    box-shadow: var(--shadow-sm);
    margin-top: clamp(2rem, 6vw, 2.6rem);
}

.contact-form-section h2,
.cannot-resolve-section h2 {
    margin-top: 0;
    font-size: clamp(1.2rem, 4vw, 1.6rem);
}

.contact-form .form-group {
    margin-bottom: 1.2rem;
}

.form-notice {
    text-align: left;
    margin: 0 auto 1.5rem;
    max-width: 640px;
}

.pre-contact-info {
    padding: 1.4rem 1.6rem;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08), rgba(59, 130, 246, 0));
    border: 1px solid rgba(59, 130, 246, 0.2);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.6);
    display: grid;
    gap: 1.1rem;
}

.pre-contact-info__header {
    display: flex;
    align-items: center;
    gap: 0.9rem;
}

.pre-contact-info__icon {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: rgba(59, 130, 246, 0.14);
    display: grid;
    place-items: center;
    color: var(--color-primary);
    flex-shrink: 0;
}

.pre-contact-info__icon svg {
    width: 22px;
    height: 22px;
    fill: currentColor;
}

.pre-contact-info__label {
    font-weight: 700;
    margin: 0;
    font-size: var(--font-size-md);
}

.pre-contact-info__description {
    margin: 0.3rem 0 0;
    color: var(--color-muted);
    font-size: var(--font-size-sm);
}

.pre-contact-info__list {
    margin: 0;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 0.75rem;
    font-size: var(--font-size-base);
}

.pre-contact-info__list li {
    position: relative;
    padding-left: 1.6rem;
    color: var(--color-text);
}

.pre-contact-info__list li::before {
    content: "";
    position: absolute;
    inset: 0 auto 0 0.1rem;
    width: 0.75rem;
    height: 0.75rem;
    border-radius: 0.3rem;
    background: var(--color-primary);
    opacity: 0.65;
    margin-top: 0.35rem;
}

.pre-contact-info__note {
    color: var(--color-muted);
    font-size: var(--font-size-sm);
}

.pre-contact-info__note::before {
    background: transparent;
    content: "※";
    inset: 0.05rem auto auto 0;
    width: auto;
    height: auto;
    margin-top: 0;
    font-weight: 700;
    color: var(--color-primary);
}

.pre-contact-info a {
    color: var(--color-primary);
    font-weight: 600;
    text-decoration: underline;
    text-decoration-color: rgba(59, 130, 246, 0.5);
    text-underline-offset: 3px;
}

.pre-contact-info a:hover {
    text-decoration-color: var(--color-primary);
}

.contact-form label {
    display: block;
    font-weight: 600;
    font-size: var(--font-size-base);
    margin-bottom: 0.4rem;
}

.contact-form input[type="text"],
.contact-form input[type="email"],
.contact-form input[type="tel"],
.contact-form select,
.contact-form textarea {
    width: 100%;
    padding: 0.75rem 0.9rem;
    font-size: var(--font-size-base);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(15, 23, 42, 0.15);
    background: #fff;
    box-shadow: inset 0 1px 2px rgba(15, 23, 42, 0.04);
}

.contact-form textarea {
    min-height: 160px;
    resize: vertical;
}

.checkbox-group input[type="checkbox"] {
    width: 18px;
    height: 18px;
    margin-top: 0.2rem;
}

.contact-button,
.contact-form button[type="submit"] {
    border: none;
    border-radius: 999px;
    padding: 0.85rem 1.8rem;
    font-size: var(--font-size-md);
    font-weight: 700;
    background: var(--color-primary);
    color: #fff;
    text-decoration: none;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    box-shadow: 0 8px 20px rgba(59, 130, 246, 0.28);
}

.contact-form button[type="submit"]:disabled {
    background: #cbd5f5;
    color: rgba(15, 23, 42, 0.5);
    box-shadow: none;
    cursor: not-allowed;
    transform: none;
}

.contact-button:hover,
.contact-form button[type="submit"]:hover {
    background: var(--color-primary-dark);
    transform: translateY(-1px);
    color: #7dd3fc;
}

.contact-form button[type="submit"]:disabled:hover {
    background: #cbd5f5;
}

.contact-button.secondary {
    background: #694766;
    box-shadow: 0 8px 20px rgba(71, 85, 105, 0.2);
}

.contact-button.secondary:hover {
    background: #334155;
}

.contact-options {
    margin-top: 1.3rem;
    display: grid;
    gap: 0.8rem;
}

.form-error-message {
    margin: 0 0 0.75rem;
    color: #dc2626;
    font-weight: 600;
}

@media (min-width: 600px) {
    .contact-options {
        grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    }
}

/* ================================================================
   フォームの共通ユーティリティとモーダル
   ================================================================ */

.required-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.15rem 0.55rem;
    border-radius: 999px;
    background: #ef4444;
    color: #fff;
    font-size: var(--font-size-xs);
    font-weight: 700;
    line-height: 1;
    margin-left: 0.5rem;
}

.auto-note {
    display: inline-block;
    margin-left: 0.5rem;
    font-size: var(--font-size-xs);
    color: var(--color-muted);
}

.contact-intro {
    margin-bottom: clamp(1.2rem, 3vw, 1.6rem);
    padding: clamp(1rem, 3vw, 1.4rem);
    border-radius: var(--radius-md);
    background: rgba(59, 130, 246, 0.08);
    border: 1px solid rgba(59, 130, 246, 0.16);
    color: var(--color-muted);
}

.contact-form input[readonly],
.contact-form textarea[readonly] {
    background: #f1f5f9;
    color: #475569;
    cursor: not-allowed;
}

.contact-form input[readonly]:focus,
.contact-form textarea[readonly]:focus {
    outline: 2px solid rgba(59, 130, 246, 0.35);
}

.device-group,
.ios-other-device-group {
    display: none;
    margin-top: 0.5rem;
}

.hidden {
    display: none;
}

.checkbox-group {
    display: flex;
    align-items: flex-start;
    gap: 0.6rem;
    font-size: var(--font-size-sm);
    color: var(--color-muted);
    flex-wrap: wrap;
}

.checkbox-group--centered {
    justify-content: center;
    text-align: center;
}

.checkbox-group label {
    margin: 0;
    color: inherit;
}

.checkbox-group a {
    color: var(--color-primary);
    font-weight: 600;
    text-decoration: none;
}

.checkbox-group a:hover {
    text-decoration: underline;
}

.help-link {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    margin-top: 0.5rem;
    padding: 0.35rem 0.85rem;
    border-radius: 999px;
    border: none;
    background: #0ea5e9;
    color: #fff;
    font-size: var(--font-size-xs);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
    box-shadow: 0 10px 25px rgba(14, 165, 233, 0.28);
}

.help-link:hover,
.help-link:focus {
    background: #0284c7;
    transform: translateY(-1px);
    color: #7dd3fc;
}

.help-modal {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background: rgba(15, 23, 42, 0.45);
    backdrop-filter: blur(2px);
    z-index: 1000;
}

.help-modal.active {
    display: flex;
}

.help-modal__dialog {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    max-width: 520px;
    width: min(100%, 520px);
    max-height: 90vh;
    overflow-y: auto;
    padding: clamp(1.2rem, 3vw, 1.6rem);
    box-shadow: var(--shadow-md);
    position: relative;
}

.help-modal__close {
    position: absolute;
    top: 0.75rem;
    right: 0.75rem;
    border: none;
    background: transparent;
    color: var(--color-muted);
    font-size: 1.35rem;
    cursor: pointer;
}

.help-modal__close:hover,
.help-modal__close:focus {
    color: var(--color-primary);
}

.help-modal__content figure {
    margin: 1rem 0;
    text-align: center;
}

.help-modal__content h3 {
    margin: 0;
    font-size: clamp(1.1rem, 3vw, 1.35rem);
}

.help-modal__content ol {
    margin: 0.75rem 0 0.75rem 1.5rem;
    padding-left: 1rem;
    text-align: left;
}

.help-modal__content li {
    margin-bottom: 0.6rem;
    color: var(--color-text);
}

.help-modal__content img {
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-sm);
}

.help-modal__content figcaption {
    margin-top: 0.5rem;
    font-size: var(--font-size-xs);
    color: var(--color-muted);
}

.notice-box {
    border-radius: var(--radius-sm);
    padding: 1rem 1.2rem;
    font-size: var(--font-size-sm);
    background: rgba(252, 211, 77, 0.16);
    border: 1px solid rgba(252, 211, 77, 0.35);
    color: #92400e;
}

.notice-box--warning {
    background: rgba(254, 243, 199, 0.85);
    border-color: rgba(245, 158, 11, 0.35);
}

.notice-box--centered {
    text-align: center;
}

.note-box {
    background: rgba(148, 163, 184, 0.12);
    border-left: 4px solid rgba(148, 163, 184, 0.6);
    border-radius: var(--radius-sm);
    padding: 1rem 1.2rem;
    font-size: var(--font-size-sm);
    color: var(--color-text);
}

.support-note {
    margin-top: clamp(1.2rem, 3vw, 1.6rem);
    font-size: var(--font-size-sm);
    color: var(--color-muted);
    text-align: center;
}

.thank-you-section {
    margin-top: clamp(2.5rem, 6vw, 3.5rem);
    padding: clamp(2.5rem, 6vw, 3.2rem);
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    text-align: center;
    display: grid;
    gap: 1.1rem;
}

.thank-you-section h2 {
    margin: 0;
    color: #16a34a;
    font-size: clamp(1.5rem, 3.5vw, 2rem);
}

.thank-you-section .contact-button {
    justify-self: center;
    background: #0f172a;
    box-shadow: 0 14px 30px rgba(15, 23, 42, 0.3);
}

.thank-you-section .contact-button:hover {
    background: #bfcfe9;
}

.guide-section {
    background: var(--color-surface);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    padding: clamp(1.2rem, 3vw, 1.8rem);
    box-shadow: var(--shadow-sm);
    margin-bottom: clamp(1.4rem, 4vw, 1.8rem);
}

.guide-section h2 {
    margin-top: 0;
}

.step-list {
    margin: 1rem 0 0 1.25rem;
    padding: 0;
}

.step-list li {
    margin-bottom: 0.75rem;
}

.cannot-resolve-section p {
    color: var(--color-muted);
    margin-bottom: 0.6rem;
}

ul,
ol {
    padding-left: 1.2rem;
}

li {
    margin-bottom: 0.4rem;
}

.table-wrapper {
    overflow-x: auto;
}

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

.table-wrapper th,
.table-wrapper td {
    padding: 0.75rem;
    border: 1px solid rgba(148, 163, 184, 0.35);
    font-size: var(--font-size-sm);
}

.table-wrapper th {
    background: rgba(59, 130, 246, 0.08);
    color: var(--color-text);
}

.notice-box,
.alert-box {
    border-radius: var(--radius-sm);
    padding: 0.9rem 1rem;
    font-size: var(--font-size-sm);
}

.notice-box {
    background: rgba(252, 211, 77, 0.18);
    border: 1px solid rgba(252, 211, 77, 0.35);
    color: #92400e;
}

.alert-box {
    background: rgba(239, 68, 68, 0.15);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #991b1b;
}

.tag-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    padding: 0;
    list-style: none;
}

.tag-list li {
    margin: 0;
}

.tag {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.35rem 0.7rem;
    border-radius: 999px;
    background: rgba(59, 130, 246, 0.12);
    color: var(--color-primary);
    font-size: var(--font-size-xs);
    font-weight: 600;
}

@media (min-width: 768px) {
    main {
        padding-inline: clamp(2rem, 6vw, 3rem);
    }

    .site-header {
        padding: 2.4rem clamp(2rem, 6vw, 4rem) 3.2rem;
    }

    .site-header .header-actions {
        gap: 1rem;
    }

    .support-hero {
        grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
        align-items: stretch;
    }

    .quick-links {
        align-self: center;
    }

    .top-faq-section ul {
        gap: 1rem;
    }

    .top-faq-section li a {
        padding: 1.1rem 1.4rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation: none !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}