@charset "utf-8";
/* ==========================================================================
   龍南建設株式会社 サイトリニューアル / 共通デザイン
   コンセプト BLUE STRATA ── 深い紺の闇に、継承したブランドの青を光として置く
   全面フル幅レイアウト。中央寄せの箱を作らず、画面の端まで使う。
   ========================================================================== */

/* ---------- トークン ---------- */
:root{
  /* 面（明るい側） */
  --ink-900:#ffffff;
  --ink-850:#f2f7fc;
  --ink-800:#e8f1f9;
  --ink-700:#e1ecf6;
  --ink-600:#d5e4f2;
  --ink-500:#bcd4e9;
  /* 濃い面（CTAなどの差し色） */
  --deep-900:#04101f;
  --deep-800:#062247;

  /* ブランドの青（現行サイトから継承） */
  --blue-700:#005cc4;
  --blue-600:#1d86eb;
  --blue-500:#2b92ee;
  --blue-400:#4facf7;
  --blue-300:#75d7f0;
  --blue-200:#9bd0ff;
  --blue-050:#ebf4f7;

  /* 文字 */
  --tx:#1b2f45;
  --tx-strong:#06121f;
  --tx-mute:#4f677c;
  --tx-faint:#6e8598;

  /* 線 */
  --line:rgba(9,42,82,.14);
  --line-soft:rgba(9,42,82,.07);
  --line-strong:rgba(9,42,82,.26);

  --grad:linear-gradient(100deg,var(--blue-700) 0%,var(--blue-500) 48%,var(--blue-300) 100%);

  /* 書体 */
  --f-mincho:"Shippori Mincho B1","Yu Mincho",YuMincho,"Hiragino Mincho ProN","Noto Serif JP",serif;
  /* 現行サイトのキャッチコピーと同じ明朝の指定 */
  --f-mintyo:"Yu Mincho",YuMincho,"Hiragino Mincho ProN","Sawarabi Mincho",serif;
  --f-sans:"Zen Kaku Gothic New","Yu Gothic Medium",YuGothic,"Hiragino Sans","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;
  --f-latin:"Barlow Condensed","Arial Narrow",Arial,sans-serif;
  --f-mono:"Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  /* 間 */
  --gut:clamp(18px,4.4vw,92px);
  --sec:clamp(86px,10vw,176px);
  --hd-h:88px;

  --ease:cubic-bezier(.22,.61,.28,1);
  --ease-out:cubic-bezier(.16,1,.3,1);
}

/* ---------- リセット ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;background:var(--ink-900);color:var(--tx);
  font-family:var(--f-sans);font-size:16px;line-height:1.9;
  font-feature-settings:"palt" 1;letter-spacing:.03em;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
}
img,svg,video{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4,h5,p,figure,dl,dd,blockquote{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
table{border-collapse:collapse;width:100%}
::selection{background:var(--blue-500);color:#fff}
:focus-visible{outline:2px solid var(--blue-300);outline-offset:3px}

/* ---------- 下地の質感 ---------- */
.grid-bg{
  position:fixed;inset:0;z-index:0;pointer-events:none;
  background-image:linear-gradient(var(--line-soft) 1px,transparent 1px),
                   linear-gradient(90deg,var(--line-soft) 1px,transparent 1px);
  background-size:clamp(64px,7vw,120px) clamp(64px,7vw,120px);
  -webkit-mask-image:radial-gradient(130% 90% at 50% 0%,#000 0%,transparent 76%);
  mask-image:radial-gradient(130% 90% at 50% 0%,#000 0%,transparent 76%);
  opacity:.6;
}
.page{position:relative;z-index:2}

/* ---------- 骨格（フル幅） ---------- */
.wrap{width:100%;padding-inline:var(--gut)}
.sec{position:relative;padding-block:var(--sec)}
.sec--light{background:#f2f6fa;color:#0a1420}
.read{max-width:42em}

/* 章見出し */
.chap{display:flex;align-items:baseline;gap:clamp(12px,1.4vw,26px);margin-bottom:clamp(34px,4.2vw,66px)}
.chap__no{
  font-family:var(--f-mono);font-size:11px;letter-spacing:.24em;color:var(--blue-400);
  padding-top:.7em;flex:none;
}
.chap__body{min-width:0}
.chap__en{
  display:block;font-family:var(--f-latin);font-weight:600;
  font-size:clamp(40px,8.4vw,140px);line-height:.86;letter-spacing:.005em;
  text-transform:uppercase;color:var(--tx-strong);
}
.chap__ja{
  display:block;margin-top:1em;font-family:var(--f-mincho);font-weight:700;
  font-size:clamp(14px,1.4vw,19px);letter-spacing:.24em;color:var(--blue-700);
}
.chap__ja::before{
  content:"";display:inline-block;width:clamp(22px,3vw,52px);height:1px;
  background:var(--blue-500);vertical-align:middle;margin-right:1.1em;
}
.chap__en::first-letter{color:var(--blue-700)}
.phero__en::first-letter{color:var(--blue-700)}
.sec--light .chap__en{color:var(--tx-strong)}
.sec--light .chap__ja{color:var(--blue-700)}
.sec--light .chap__no{color:var(--blue-700)}

.tag{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.24em;text-transform:uppercase;color:var(--tx-mute)}
.hr{height:1px;background:var(--line);border:0;margin:0}

/* ---------- ボタン ---------- */
.btn{
  --bg:transparent;--fg:var(--tx-strong);--bd:var(--line-strong);
  position:relative;display:inline-flex;align-items:center;gap:1.2em;
  padding:1.1em 1.5em 1.1em 1.8em;background:var(--bg);color:var(--fg);
  border:1px solid var(--bd);font-size:13px;letter-spacing:.16em;font-weight:500;
  overflow:hidden;isolation:isolate;transition:color .45s var(--ease),border-color .45s var(--ease);
}
.btn span{position:relative;z-index:1}
.btn::before{
  content:"";position:absolute;inset:0;z-index:0;background:var(--grad);
  transform:translateY(101%);transition:transform .55s var(--ease-out);
}
.btn:hover{color:#fff;border-color:transparent}
.btn:hover::before{transform:translateY(0)}
.btn__arw{position:relative;z-index:1;width:28px;height:8px;flex:none;overflow:hidden}
.btn__arw::before,.btn__arw::after{
  content:"";position:absolute;top:50%;left:0;width:28px;height:1px;background:currentColor;
  transition:transform .55s var(--ease-out);
}
.btn__arw::after{transform:translateX(-100%)}
.btn:hover .btn__arw::before{transform:translateX(100%)}
.btn:hover .btn__arw::after{transform:translateX(0)}
.btn--fill{--bg:var(--blue-600);--bd:var(--blue-600);--fg:#fff}
.btn--fill::before{background:linear-gradient(100deg,var(--deep-800),var(--blue-700))}
.btn--fill:hover{border-color:var(--blue-500)}
.btn--dark{--fg:#08131f;--bd:rgba(8,19,31,.25)}
.btn--dark:hover{--fg:#fff}
.btn--lg{padding:1.35em 1.9em 1.35em 2.2em;font-size:14px}
.btn--block{display:flex;justify-content:space-between;width:100%}

.ln{position:relative;display:inline-block;padding-bottom:.15em}
.ln::after{
  content:"";position:absolute;left:0;bottom:0;width:100%;height:1px;background:currentColor;
  transform:scaleX(0);transform-origin:right;transition:transform .5s var(--ease-out);
}
.ln:hover::after{transform:scaleX(1);transform-origin:left}

/* ---------- ヘッダー ---------- */
.hd{
  position:fixed;inset:0 0 auto;z-index:80;
  transition:background-color .5s var(--ease),backdrop-filter .5s var(--ease),
             border-color .5s var(--ease),transform .5s var(--ease);
  border-bottom:1px solid transparent;
}
.hd.is-stuck{
  background:rgba(255,255,255,.88);backdrop-filter:blur(20px) saturate(150%);
  -webkit-backdrop-filter:blur(20px) saturate(150%);border-bottom-color:var(--line-soft);
}
.hd.is-hidden{transform:translateY(-101%)}
.hd__in{
  display:flex;align-items:center;gap:clamp(14px,2vw,40px);
  height:var(--hd-h);padding-inline:var(--gut);transition:height .5s var(--ease);
}
.hd.is-stuck .hd__in{height:70px}
.hd__logo{--logo-h:clamp(27px,2.5vw,35px);flex:none;display:flex;align-items:center;gap:.6em}
.hd__logo .mark{height:var(--logo-h);width:auto;position:relative;top:1px}
.hd__logo .word{height:calc(var(--logo-h) * .755);width:auto}
.hd.is-stuck .hd__logo{--logo-h:clamp(25px,2.2vw,31px)}
.hd__in>nav{margin-left:auto}
.hd__nav{display:flex;align-items:center;justify-content:flex-end;gap:clamp(14px,1.7vw,30px)}
.hd__nav>li{position:relative}
.hd__nav a{
  display:block;text-align:center;font-size:clamp(14px,1.12vw,16px);letter-spacing:.06em;color:var(--tx-strong);font-weight:500;white-space:nowrap;
  position:relative;padding-block:.5em;transition:color .35s var(--ease);
}
.hd__nav a small{
  display:block;font-family:var(--f-mono);font-size:9.5px;letter-spacing:.18em;
  color:var(--tx-mute);margin-top:.3em;text-indent:.18em;transition:color .35s var(--ease);
}
.hd__nav a::after{
  content:"";position:absolute;left:0;bottom:0;width:100%;height:1px;background:var(--blue-400);
  transform:scaleX(0);transform-origin:right;transition:transform .45s var(--ease-out);
}
.hd__nav a:hover::after{transform:scaleX(1);transform-origin:left}
.hd__nav a:hover small{color:var(--blue-300)}

/* ドロップダウン */
.hd__dd{
  position:absolute;top:100%;left:50%;translate:-50% 0;min-width:250px;padding-top:18px;
  opacity:0;visibility:hidden;transform:translateY(8px);
  transition:opacity .4s var(--ease),transform .4s var(--ease),visibility .4s;
}
.hd__nav>li:hover .hd__dd,.hd__nav>li:focus-within .hd__dd{opacity:1;visibility:visible;transform:none}
.hd__dd ul{
  background:rgba(255,255,255,.97);backdrop-filter:blur(20px);
  border:1px solid var(--line);padding:10px 0;box-shadow:0 24px 60px -24px rgba(6,40,80,.3);
}
.hd__dd a{padding:.72em 1.4em;font-size:12.5px}
.hd__dd a::after{display:none}
.hd__dd a:hover{background:rgba(43,146,238,.1);color:var(--blue-700)}

.hd__cta{display:flex;gap:8px;flex:none}
.hd__cta a{
  display:inline-flex;align-items:center;gap:.7em;padding:1em 1.35em;
  font-size:13.5px;letter-spacing:.1em;font-weight:500;border:1px solid var(--line-strong);
  transition:background-color .4s var(--ease),border-color .4s var(--ease),color .4s var(--ease),filter .4s;
}
.hd__cta a:hover{background:var(--blue-600);border-color:var(--blue-600);color:#fff}
.hd__cta a.is-key{background:var(--blue-600);border-color:var(--blue-600);color:#fff}
.hd__cta a.is-key:hover{background:var(--blue-700);border-color:var(--blue-700)}
.hd__burger{display:none}

/* モバイルメニュー */
.mnav{
  position:fixed;inset:0;z-index:90;background:var(--ink-850);
  clip-path:inset(0 0 100% 0);transition:clip-path .75s var(--ease-out);
  overflow-y:auto;overscroll-behavior:contain;
}
.mnav.is-open{clip-path:inset(0 0 0 0)}
.mnav__in{padding:calc(var(--hd-h) + 26px) var(--gut) 64px}
.mnav__list li{border-bottom:1px solid var(--line-soft)}
.mnav__list>li>a{display:flex;align-items:baseline;gap:1em;padding:1.05em 0}
.mnav__list .ja{font-family:var(--f-mincho);font-size:clamp(21px,6.2vw,32px);font-weight:700;letter-spacing:.06em}
.mnav__list .en{font-family:var(--f-mono);font-size:9px;letter-spacing:.22em;color:var(--tx-faint)}
.mnav__sub{display:flex;flex-wrap:wrap;gap:8px;padding:2px 0 20px}
.mnav__sub a{font-size:12px;letter-spacing:.08em;padding:.5em .95em;border:1px solid var(--line);color:var(--tx-mute)}
.mnav__cta{display:grid;gap:10px;margin-top:34px}
.mnav__info{margin-top:32px;font-family:var(--f-mono);font-size:12px;line-height:2.1;letter-spacing:.06em;color:var(--tx-mute)}

/* ---------- 下層ヘッダービジュアル ---------- */
.phero{position:relative;min-height:clamp(400px,50vw,660px);display:flex;align-items:flex-end;overflow:hidden}
.phero__bg{position:absolute;inset:0;z-index:0}
.phero__bg img{width:100%;height:100%;object-fit:cover;opacity:.94;animation:kb 26s var(--ease) infinite alternate}
.phero__bg::after{
  content:"";position:absolute;inset:0;
  background:linear-gradient(180deg,rgba(255,255,255,.62) 0%,rgba(255,255,255,.2) 26%,rgba(255,255,255,.86) 74%,var(--ink-900) 100%),
             linear-gradient(100deg,rgba(255,255,255,.9) 0%,rgba(255,255,255,.72) 44%,rgba(255,255,255,.18) 78%,transparent 100%);
}
.phero__in{position:relative;z-index:1;width:100%;padding:0 var(--gut) clamp(42px,5.2vw,86px)}
.phero__en{
  font-family:var(--f-latin);font-weight:600;text-transform:uppercase;
  font-size:clamp(46px,12vw,186px);line-height:.84;letter-spacing:.004em;color:var(--tx-strong);
  text-shadow:0 1px 2px rgba(255,255,255,.85);
}
.phero__ja{margin-top:1em;font-family:var(--f-mincho);font-weight:700;font-size:clamp(15px,1.7vw,22px);letter-spacing:.2em;color:var(--blue-700)}
.phero__lead{margin-top:1.6em;max-width:34em;font-size:clamp(14px,1.3vw,16.5px);line-height:2.15;color:var(--tx)}
@keyframes kb{from{transform:scale(1.03)}to{transform:scale(1.13)}}

.crumb{padding:20px 0 0;font-family:var(--f-mono);font-size:11px;letter-spacing:.14em;color:var(--tx-mute)}
.crumb ol{display:flex;flex-wrap:wrap;gap:.7em;align-items:center}
.crumb li+li::before{content:"/";margin-right:.7em;color:var(--line-strong)}
.crumb a:hover{color:var(--blue-300)}

/* ---------- CTA ---------- */
.cta{position:relative;overflow:hidden;color:#fff;
  background:linear-gradient(104deg,#0c62bd 0%,#1d86eb 42%,#2b92ee 68%,#63c6ef 100%)}
.cta__ttl{color:#fff}
.cta .btn{--fg:#fff;--bd:rgba(255,255,255,.42)}
.cta .btn--fill{--bg:#fff;--bd:#fff;--fg:var(--blue-700)}
.cta .btn--fill::before{background:var(--grad)}
.cta .btn--fill:hover{--fg:#fff;border-color:transparent}
.cta .tag{color:rgba(255,255,255,.72)}
.cta__bg{position:absolute;inset:0;z-index:0}
.cta__bg img{width:100%;height:100%;object-fit:cover;opacity:.4}
.cta__bg::after{content:"";position:absolute;inset:0;background:linear-gradient(96deg,rgba(12,98,189,.94) 12%,rgba(29,134,235,.82) 52%,rgba(99,198,239,.6) 100%)}
.cta__in{position:relative;z-index:1;display:grid;gap:clamp(28px,3.4vw,56px);grid-template-columns:minmax(0,1fr) auto;align-items:end}
.cta__ttl{font-family:var(--f-latin);font-weight:600;text-transform:uppercase;font-size:clamp(44px,9.5vw,152px);line-height:.86}
.cta__ja{margin-top:1em;font-family:var(--f-mincho);font-weight:700;font-size:clamp(15px,1.6vw,20px);letter-spacing:.16em;color:#fff}
.cta__txt{margin-top:1.5em;max-width:31em;color:rgba(255,255,255,.88);font-size:14.5px;line-height:2.15}
.cta__btns{display:grid;gap:12px;justify-items:stretch;margin-right:clamp(0px,7vw,132px)}
.cta__btns .btn{width:auto;min-width:clamp(252px,23vw,322px);gap:1.9em;padding:1.28em 1.6em 1.28em 1.85em;font-size:14px}

/* ---------- フッター ---------- */
.ft{position:relative;overflow:hidden;background:var(--ink-850);border-top:1px solid var(--line-soft);padding-top:clamp(40px,4.4vw,68px)}
.ft>.wrap{position:relative;z-index:1}
.ft__top{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.5fr);gap:clamp(26px,3.6vw,70px)}
.ft__logo{--logo-h:clamp(30px,2.9vw,40px);display:flex;align-items:center;gap:.6em}
.ft__logo .mark{height:var(--logo-h);width:auto;position:relative;top:1px}
.ft__logo .word{height:calc(var(--logo-h) * .755);width:auto}
.ft__addr{margin-top:1.3em;font-family:var(--f-mono);font-size:12px;line-height:1.95;letter-spacing:.05em;color:var(--tx-mute)}
.ft__tel{display:block;margin-top:.7em;font-family:var(--f-latin);font-size:clamp(24px,2.8vw,36px);font-weight:600;letter-spacing:.03em;color:var(--tx-strong)}
.ft__nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(20px,3vw,48px)}
.ft__nav h3{font-family:var(--f-mono);font-size:10px;letter-spacing:.24em;color:var(--blue-700);margin-bottom:1.2em;text-transform:uppercase}
.ft__nav li{margin-bottom:.62em}
.ft__nav a{font-size:13px;color:var(--tx-mute);transition:color .3s var(--ease)}
.ft__nav a:hover{color:var(--blue-700)}
.ft__bot{
  margin-top:clamp(20px,2.4vw,34px);
  padding-block:18px;display:flex;flex-wrap:wrap;gap:12px 26px;align-items:center;
  font-family:var(--f-mono);font-size:10.5px;letter-spacing:.12em;color:var(--tx-mute);
}
.ft__bot nav{display:flex;gap:22px;margin-left:auto}
.ft__bot a:hover{color:var(--blue-300)}

.totop{
  position:fixed;right:clamp(14px,1.8vw,30px);bottom:clamp(14px,1.8vw,30px);z-index:70;
  width:54px;height:54px;display:grid;place-items:center;border:1px solid var(--line-strong);
  background:rgba(255,255,255,.85);backdrop-filter:blur(10px);
  opacity:0;visibility:hidden;transform:translateY(12px);
  transition:opacity .45s var(--ease),transform .45s var(--ease),visibility .45s,background-color .4s,border-color .4s;
}
.totop.is-on{opacity:1;visibility:visible;transform:none}
.totop:hover{background:var(--blue-600);border-color:var(--blue-600)}
.totop::before{content:"";width:9px;height:9px;border-left:1px solid currentColor;border-top:1px solid currentColor;transform:rotate(45deg) translate(2px,2px)}

/* ---------- スクロール演出 ---------- */
.js .rv{opacity:0;transform:translateY(28px);transition:opacity 1s var(--ease-out),transform 1s var(--ease-out)}
.rv.is-in{opacity:1;transform:none}
.rv-d1{transition-delay:.09s}.rv-d2{transition-delay:.18s}.rv-d3{transition-delay:.27s}
.rv-d4{transition-delay:.36s}.rv-d5{transition-delay:.45s}
.js .rv-clip{clip-path:inset(0 100% 0 0);transition:clip-path 1.15s var(--ease-out)}
.rv-clip.is-in{clip-path:inset(0 0 0 0)}
.rv-img{overflow:hidden}
.js .rv-img img{transform:scale(1.15);transition:transform 1.6s var(--ease-out)}
.rv-img.is-in img{transform:scale(1)}

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important}
  html{scroll-behavior:auto}
}

/* ---------- レスポンシブ ---------- */
@media (max-width:1240px){
  .hd__nav,.hd__cta{display:none}
  .hd__burger{
    display:flex;flex-direction:column;justify-content:center;align-items:center;gap:7px;
    margin-left:auto;width:54px;height:54px;border:1px solid var(--line-strong);
    transition:background-color .4s var(--ease),border-color .4s var(--ease);
  }
  .hd__burger span{display:block;width:20px;height:1px;background:currentColor;transition:transform .5s var(--ease-out),opacity .3s}
  .hd__burger.is-open{background:var(--blue-600);border-color:var(--blue-600)}
  .hd__burger.is-open span:nth-child(1){transform:translateY(4px) rotate(45deg)}
  .hd__burger.is-open span:nth-child(2){opacity:0}
  .hd__burger.is-open span:nth-child(3){transform:translateY(-4px) rotate(-45deg)}
}
@media (min-width:1241px){.mnav{display:none}}
@media (max-width:900px){
  .cta__in{grid-template-columns:1fr}
  .ft__top{grid-template-columns:1fr}
}
@media (max-width:640px){
  body{font-size:15px}
  :root{--hd-h:72px}
  .ft__nav{grid-template-columns:1fr 1fr}
  .ft__bot nav{margin-left:0;width:100%;flex-wrap:wrap;gap:14px}
}