/* ===========================
   Responsive — Mobile First
   =========================== */

/* ===========================
   SP: max-width: 767px
   =========================== */

@media (max-width: 767px) {
  /* --- Fullscreen Menu --- */
  .fullscreen-menu__columns { grid-template-columns: 1fr; gap: 0; }
  /* FB-R2 ⑥: Stagger animation handled by JS for SP single-column */

  /* --- Layout --- */
  .container { padding: 0 var(--content-padding-sp); }
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }

  /* --- Header --- */
  .site-header { height: var(--header-height-sp); }
  .site-header__inner { padding: 0 var(--content-padding-sp); }
  .site-header__logo img { height: 22px; }
  .site-header__menu-btn { width: 40px; height: 40px; }

  /* --- Page Header (English title overflow) --- */
  .page-header__en {
    font-size: clamp(1.6rem, 8vw, 2.4rem);
    word-break: break-word;
    overflow-wrap: break-word;
  }

  /* --- Hero --- */
  .hero { margin-top: var(--header-height-sp); }
  .hero__text-area {
    height: calc(50svh - var(--header-height-sp) / 2);
    padding: 0 var(--content-padding-sp);
  }
  .hero__content { flex-direction: column; gap: 24px; }
  .hero__title { font-size: clamp(1.5rem, 5.5vw, 2rem); }
  .hero__title br { display: none; }
  .hero__br-sp { display: inline; }
  .hero__br-pc { display: none; }
  .hero__sub { margin-bottom: 0; }
  .hero__actions { flex-direction: row; }
  .hero__actions .btn { font-size: 0.8125rem; }

  /* --- Mission Quote / Lead (line break) --- */
  .mission-quote br { display: none; }
  .section__lead br { display: none; }

  /* --- Why Now (editorial list → stacked on SP) --- */
  .why-now-item {
    flex-direction: column;
    gap: 8px;
  }
  .why-now-item__number { min-width: unset; }

  /* --- Reasons (overlap → stacked on SP) --- */
  .reasons-item,
  .reasons-item:nth-child(even) {
    grid-template-columns: 1fr;
    margin-bottom: 48px;
  }
  .reasons-item__photo {
    grid-column: 1;
    grid-row: 1;
  }
  .reasons-item__text {
    grid-column: 1;
    grid-row: 2;
    margin-left: 0;
    margin-top: -24px;
    margin-right: 0;
    padding: 24px;
  }
  .reasons-item:nth-child(even) .reasons-item__photo { grid-column: 1; }
  .reasons-item:nth-child(even) .reasons-item__text { margin-right: 0; }

  /* --- Background Points --- */
  .section--sb-background [style*="grid-template-columns"] {
    grid-template-columns: 1fr !important;
    gap: 24px !important;
  }

  /* --- News --- */
  .news-item { flex-wrap: wrap; gap: 4px 12px; }
  .news-item__title {
    width: 100%;
    white-space: normal;
    -webkit-line-clamp: 2;
    display: -webkit-box;
    -webkit-box-orient: vertical;
    overflow: hidden;
  }

  /* --- Footer --- */
  .site-footer__grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .site-footer__brand { text-align: center; }
  .site-footer__bottom { text-align: center; }

  /* --- Info Table --- */
  .info-table--dl .info-table__row { flex-direction: column; gap: 4px; }
  .info-table__label { width: auto; }
  .info-table--compare { overflow-x: auto; -webkit-overflow-scrolling: touch; }

  /* --- Step Flow (vertical) --- */
  .step-flow { flex-direction: column; align-items: stretch; }
  .step-flow__item {
    display: flex;
    text-align: left;
    gap: 16px;
    padding: 16px 0;
  }
  .step-flow__number { margin: 0; flex-shrink: 0; }
  .step-flow__connector {
    width: 2px;
    height: 24px;
    margin: 0 0 0 23px;
  }
  .step-flow__connector::after {
    right: auto; top: auto;
    bottom: -4px; left: -4px;
    border: 5px solid transparent;
    border-top-color: var(--color-border);
    border-left-color: transparent;
  }

  /* --- Hero --- */
  .hero__actions { flex-direction: column; align-items: flex-start; }
  .hero__actions .btn { width: 100%; max-width: 280px; }

  /* --- Contact Sidebar → SP Floating CTA --- */
  .contact-sidebar { display: none; }
  .sp-cta { display: block; }

  /* --- News Card (stacked on SP) --- */
  .news-card { flex-direction: column; }
  .news-card__thumb { width: 100%; }

  /* --- Page Top button --- */
  .page-top { bottom: 16px; right: 16px; width: 40px; height: 40px; }

  /* Form responsive → css/form.css */

  /* --- Contact Grid --- */
  .contact-grid { grid-template-columns: 1fr; }
  .contact-aside { position: static; }

  /* --- Filter Bar --- */
  .filter-bar { flex-direction: column; gap: 12px; }
  .filter-bar__buttons { flex-wrap: wrap; }
  .filter-bar__btn { padding: 6px 12px; }

  /* --- Team Profile --- */
  .team-profile,
  .team-profile:nth-child(even) {
    grid-template-columns: 1fr;
    direction: ltr;
    gap: 20px;
  }
  .team-profile__photo { max-width: 200px; }

  /* --- Access Grid --- */
  .access-grid { grid-template-columns: 1fr; }

  /* --- Article Nav --- */
  .article-nav { flex-direction: column; gap: 16px; }

  /* --- FB-01: Hero text-area SP margin fix --- */
  .hero__text-area {
    height: auto;
    min-height: calc(50svh - var(--header-height-sp) / 2);
    padding: clamp(32px, 6vw, 48px) var(--content-padding-sp);
  }

  /* --- FB-03/09: Business & Energy lead text left-align on SP --- */
  .section--biz-lead .section__lead,
  .section--energy-lead .section__lead {
    text-align: left;
  }

  /* --- FB-04: Comparison table vertical layout on SP --- */
  .info-table--compare {
    border: none;
    border-radius: 0;
    overflow: visible;
  }
  .info-table--compare table,
  .info-table--compare thead,
  .info-table--compare tbody,
  .info-table--compare tr,
  .info-table--compare th,
  .info-table--compare td {
    display: block;
    width: 100%;
  }
  .info-table--compare thead { display: none; }
  .info-table--compare tbody tr {
    margin-bottom: 28px;
    margin-left: 0;
    margin-right: 24px;
    padding: 24px 16px 16px;
    border: 1px solid var(--color-border-light);
    background: var(--color-primary);
    border-radius: 0;
    position: relative;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    border-color: var(--color-primary);
  }
  .info-table--compare tbody tr:nth-child(even) {
    background: var(--color-primary);
  }
  .info-table--compare tbody tr:last-child {
    margin-bottom: 0;
  }
  /* th: overlap tag — floats above the card top edge */
  .info-table--compare tbody th {
    position: absolute;
    top: -12px;
    left: -8px;
    font-size: var(--fs-small);
    font-weight: var(--fw-semibold);
    color: var(--color-text);
    background: var(--color-primary);
    border: none;
    padding: 8px 24px 8px 16px;
    clip-path: polygon(0 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
    z-index: 1;
    width: auto;
    display: inline-block;
    margin: 0;
    white-space: nowrap;
    letter-spacing: 0.06em;
  }
  .info-table--compare tbody th::after {
    content: "";
    position: absolute;
    top: 1px;
    left: 1px;
    right: 1px;
    bottom: 1px;
    background: var(--color-white);
    clip-path: polygon(0 0, 100% 0, calc(100% - 10px) 100%, 0 100%);
    z-index: -1;
  }
  .info-table--compare tbody td {
    padding: 8px 0;
    font-size: var(--fs-small);
    color: rgba(255, 255, 255, 0.85);
    position: relative;
    border-bottom: 1px solid rgba(255, 255, 255, 0.15);
  }
  .info-table--compare tbody td:last-child {
    font-weight: var(--fw-medium);
    color: var(--color-white);
    border-bottom: none;
    padding-bottom: 0;
  }
  .info-table--compare tbody td::before {
    content: attr(data-label);
    display: block;
    font-size: var(--fs-caption);
    font-weight: var(--fw-medium);
    color: rgba(255, 255, 255, 0.5);
    margin-bottom: 2px;
  }

  /* --- FB-06/10: Risk & Domains icons center on SP --- */
  .feature-item--left {
    text-align: center;
  }
  .feature-item--left .feature-item__icon {
    margin: 0 auto 12px;
  }

  /* --- FB-07/08: Step flow vertical center alignment --- */
  .step-flow__item {
    align-items: center;
  }
  /* Remove bottom margin on title when it's the only child (e.g. CTA step flow) */
  .step-flow__title:last-child {
    margin-bottom: 0;
  }

  /* --- FB-R2 ⑤: CTA section step-flow SP layout --- */
  .cta-banner .step-flow {
    gap: 0;
  }
  .cta-banner .step-flow__item {
    padding: 12px 0;
  }
  .cta-banner .step-flow__connector {
    background: rgba(255, 255, 255, 0.3) !important;
    margin-left: 23px;
    height: 20px;
  }

  /* --- FB-11: Breadcrumb on dark header — improve visibility --- */
  .page-header--has-image .breadcrumb__item,
  .page-header--has-image .breadcrumb__item a {
    font-size: 0.6875rem;
    text-shadow: 0 1px 4px rgba(0, 0, 0, 0.6);
  }
  .page-header--has-image .breadcrumb__list {
    flex-wrap: wrap;
    gap: 4px;
  }

  /* --- FB-05: Scheme section — margin between text and diagram (SP) --- */
  .scheme__lead {
    margin-bottom: clamp(24px, 4vw, 32px);
  }

  /* FB-12: form padding → css/form.css */

}

/* ===========================
   Tablet: 768px - 991px
   =========================== */

@media (min-width: 768px) and (max-width: 991px) {
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }

  .site-header { height: var(--header-height-sp); }
  .site-header__inner { padding: 0 var(--content-padding-sp); }
  .site-header__logo img { height: 22px; }
  .site-header__menu-btn { width: 40px; height: 40px; }

  .hero { margin-top: var(--header-height-sp); }
  .hero__text-area { height: calc(50svh - var(--header-height-sp) / 2); }

  .site-footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  /* --- Contact Grid --- */
  .contact-grid { grid-template-columns: 1fr; }
  .contact-aside { position: static; }

  /* Step flow vertical on tablet too */
  .step-flow { flex-direction: column; align-items: stretch; }
  .step-flow__item {
    display: flex;
    text-align: left;
    gap: 16px;
    padding: 16px 0;
  }
  .step-flow__number { margin: 0; flex-shrink: 0; }
  .step-flow__connector {
    width: 2px;
    height: 24px;
    margin: 0 0 0 23px;
  }
  .step-flow__connector::after {
    right: auto; top: auto;
    bottom: -4px; left: -4px;
    border: 5px solid transparent;
    border-top-color: var(--color-border);
    border-left-color: transparent;
  }

  .page-header { margin-top: var(--header-height-sp); }

  /* Contact sidebar → SP CTA on tablet too */
  .contact-sidebar { display: none; }
  .sp-cta { display: block; }
}

/* ===========================
   PC: min-width: 992px
   =========================== */

@media (min-width: 992px) {
  .site-header__nav { display: block; }

  /* --- FB-13: Hero subtext — force single line on PC --- */
  .hero__sub {
    max-width: none;
  }

  /* --- FB-14: WHAT IS section — center + full width on PC --- */
  .biz-detail__title {
    text-align: center;
  }
  .biz-detail__desc {
    max-width: none;
  }
  .section--alt .biz-detail {
    max-width: none;
  }

  /* --- FB-15 PC: Scheme text full width + margin --- */
  .scheme__lead {
    max-width: none;
    text-align: center;
    margin-bottom: clamp(32px, 4vw, 48px);
  }
}

/* ===========================
   Wide: min-width: 1300px
   =========================== */

@media (min-width: 1300px) {
  .container { padding: 0 60px; }
}