/* ============================================================
   Lien Dental Clinic — common.css
   全ページ共通スタイル
   ------------------------------------------------------------
   読み込み方:
     ルート直下のHTML   <link rel="stylesheet" href="css/common.css">
     menu/* 配下のHTML <link rel="stylesheet" href="../css/common.css">

   目次:
     01. Design Tokens (CSS Variables)
     02. Reset & Base
     03. Container & Layout Utility
     04. Typography Utilities
     05. Button System
     06. Header
     07. Global Navigation
     08. Mobile Navigation
     09. Footer
     10. Fixed Bottom-Right CTA
     11. Breadcrumbs
     12. Reveal Animation Utility (Scroll-triggered)
     13. Reduced Motion Override
   ============================================================ */


/* ============================================================
   01. Design Tokens (CSS Variables)
   ============================================================ */
:root {
  /* Base */
  --color-bg-primary: #FFFFFF;
  --color-bg-secondary: #FAFBFC;

  /* Trust-blue family (medical trust signal) */
  --color-primary-light: #B8D4E3;
  --color-primary-main: #6B8FA8;
  --color-primary-dark: #4A6E87;
  --color-primary-deep: #2F4A5C;

  /* Warm accents (5–10% use only) */
  --color-accent-warm: #E8DCC8;
  --color-accent-soft: #F5D4CA;
  --color-accent-deep: #C97B6A;

  /* Text */
  --color-text-primary: #2C3E50;
  --color-text-secondary: #5A6B7E;
  --color-text-muted: #8B9AAA;

  /* Lines */
  --color-line: #E4EAF0;
  --color-line-soft: #F0F4F7;

  /* Gradients */
  --gradient-soft: linear-gradient(135deg, #FAFBFC 0%, #F0F5F8 100%);

  /* Fonts - 游ゴシックに統一 */
  --font-yu: "YuGothic", "Yu Gothic Medium", "Yu Gothic", "游ゴシック Medium", "游ゴシック体", "ヒラギノ角ゴ ProN W3", "Hiragino Kaku Gothic ProN", "Hiragino Sans", "メイリオ", "Meiryo", sans-serif;
  --font-serif-jp: var(--font-yu);
  --font-sans-jp: var(--font-yu);
  --font-serif-en: var(--font-yu);
  --font-sans-en: var(--font-yu);

  /* Spacing */
  --space-section: clamp(72px, 9vw, 120px);
  --container-max: 1280px;
  --container-pad: clamp(20px, 4vw, 56px);

  /* Misc */
  --header-height: 84px;
}


/* ============================================================
   02. Reset & Base
   ============================================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans-jp);
  font-weight: 400;
  color: var(--color-text-primary);
  background: var(--color-bg-primary);
  line-height: 1.85;
  font-feature-settings: "palt";
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img,
picture,
svg,
video {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: opacity .3s ease, color .3s ease;
}
a:hover { opacity: 0.7; }

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

ul, ol { list-style: none; }

/* Screen-reader only utility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


/* ============================================================
   03. Container & Layout Utility
   ============================================================ */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-pad);
}

.container-narrow {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 var(--container-pad);
}


/* ============================================================
   04. Typography Utilities
   ============================================================ */

/* Eyebrow (small label above headings) */
.eyebrow {
  font-family: var(--font-serif-en);
  font-size: 13px;
  letter-spacing: 0.34em;
  text-transform: uppercase;
  color: var(--color-primary-main);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 14px;
}
.eyebrow::before {
  content: "";
  width: 36px;
  height: 1px;
  background: var(--color-primary-main);
}
.eyebrow.is-centered {
  justify-content: center;
}
.eyebrow.is-centered::after {
  content: "";
  width: 36px;
  height: 1px;
  background: var(--color-primary-main);
}

/* Section heading */
.section-title {
  font-family: var(--font-serif-jp);
  font-weight: 500;
  font-size: clamp(26px, 3.4vw, 40px);
  line-height: 1.6;
  letter-spacing: 0.06em;
  margin-top: 18px;
  color: var(--color-text-primary);
}
.section-title em {
  font-style: normal;
  color: var(--color-primary-dark);
  position: relative;
}
.section-title em::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--color-accent-soft);
}

/* Section lead text */
.section-lead {
  font-size: 14.5px;
  color: var(--color-text-secondary);
  line-height: 2;
  margin-top: 20px;
  max-width: 620px;
}

/* Text link button (no background, underline-arrow style) */
.btn-text {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  font-size: 12.5px;
  letter-spacing: 0.18em;
  font-weight: 500;
  color: var(--color-primary-dark);
  padding: 14px 0;
  font-family: var(--font-sans-jp);
}
.btn-text .arrow {
  width: 24px;
  height: 1px;
  background: currentColor;
  position: relative;
  transition: width .35s ease;
}
.btn-text .arrow::after {
  content: "";
  position: absolute;
  right: 0;
  top: -3px;
  width: 7px;
  height: 7px;
  border-top: 1px solid currentColor;
  border-right: 1px solid currentColor;
  transform: rotate(45deg);
}
.btn-text:hover {
  opacity: 1;
  color: var(--color-primary-deep);
}
.btn-text:hover .arrow {
  width: 36px;
}


/* ============================================================
   05. Button System
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 18px 30px;
  font-size: 12.5px;
  letter-spacing: 0.16em;
  font-weight: 500;
  transition: all .35s cubic-bezier(.4, 0, .2, 1);
  position: relative;
  border: 1px solid transparent;
  font-family: var(--font-sans-jp);
  cursor: pointer;
}

/* Primary button (filled white, dark text) — for use on dark backgrounds */
.btn-primary {
  background: #fff;
  color: var(--color-text-primary);
}
.btn-primary:hover {
  background: var(--color-accent-soft);
  color: var(--color-text-primary);
  opacity: 1;
  transform: translateY(-2px);
}

/* Ghost button (outlined) — for use on dark backgrounds */
.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.6);
}
.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: #fff;
  opacity: 1;
  transform: translateY(-2px);
}

/* CTA primary button (dark blue, for light backgrounds) */
.btn-cta-primary {
  background: var(--color-primary-dark);
  color: #fff;
}
.btn-cta-primary:hover {
  background: var(--color-primary-deep);
  color: #fff;
  opacity: 1;
  transform: translateY(-2px);
}

/* LINE button */
.btn-cta-line {
  background: #06C755;
  color: #fff;
}
.btn-cta-line:hover {
  background: #05B348;
  color: #fff;
  opacity: 1;
  transform: translateY(-2px);
}

/* Outline button (for light backgrounds) */
.btn-outline {
  background: transparent;
  color: var(--color-text-primary);
  border-color: var(--color-text-primary);
}
.btn-outline:hover {
  background: var(--color-text-primary);
  color: #fff;
  opacity: 1;
  transform: translateY(-2px);
}

/* Arrow inside .btn */
.btn .arrow {
  width: 18px;
  height: 1px;
  background: currentColor;
  position: relative;
  transition: width .3s ease;
}
.btn .arrow::after {
  content: "";
  position: absolute;
  right: 0;
  top: -3px;
  width: 7px;
  height: 7px;
  border-top: 1px solid currentColor;
  border-right: 1px solid currentColor;
  transform: rotate(45deg);
}
.btn:hover .arrow {
  width: 26px;
}


/* ============================================================
   06. Header
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--color-line-soft);
}

.header-top {
  display: none;
  border-bottom: 1px solid var(--color-line-soft);
  padding: 8px 0;
  font-size: 12px;
  color: var(--color-text-secondary);
  background: var(--color-bg-secondary);
}
.header-top .container {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 28px;
}
.header-top .phone {
  font-family: var(--font-serif-en);
  font-size: 14px;
  color: var(--color-text-primary);
  letter-spacing: 0.04em;
  font-weight: 500;
}

.header-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 0;
}

/* Logo */
.logo {
  display: flex;
  flex-direction: column;
  line-height: 1.05;
}
.logo-mark {
  font-family: var(--font-serif-en);
  font-size: 26px;
  letter-spacing: 0.06em;
  font-weight: 500;
  color: var(--color-text-primary);
}
.logo-mark span { color: var(--color-primary-main); }
.logo-sub {
  font-family: var(--font-sans-en);
  font-size: 9.5px;
  letter-spacing: 0.32em;
  color: var(--color-text-muted);
  margin-top: 6px;
  font-weight: 400;
}

/* Header right-side CTA cluster */
.header-cta {
  display: none;
  align-items: center;
  gap: 20px;
}
.phone-box {
  text-align: right;
  line-height: 1.3;
}
.phone-box .phone-num {
  font-family: var(--font-serif-en);
  font-size: 20px;
  letter-spacing: 0.04em;
  color: var(--color-text-primary);
  font-weight: 500;
}
.phone-box .phone-hours {
  font-size: 10.5px;
  color: var(--color-text-muted);
  letter-spacing: 0.06em;
}
.btn-reserve {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary-dark);
  color: #fff;
  padding: 14px 26px;
  font-size: 12.5px;
  letter-spacing: 0.14em;
  font-weight: 500;
  transition: background .3s ease, transform .3s ease;
}
.btn-reserve:hover {
  background: var(--color-primary-deep);
  opacity: 1;
  transform: translateY(-2px);
}


/* ============================================================
   07. Global Navigation (Desktop)
   ============================================================ */
.global-nav { display: none; }
.global-nav > ul {
  display: flex;
  align-items: center;
  gap: clamp(20px, 2.6vw, 38px);
}
.global-nav a {
  font-size: 13.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--color-text-primary);
  position: relative;
  padding: 8px 0;
  display: inline-block;
}
.global-nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 2px;
  height: 1px;
  background: var(--color-primary-main);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform .35s cubic-bezier(.6, .05, .3, 1);
}
.global-nav a:hover {
  opacity: 1;
  color: var(--color-primary-dark);
}
.global-nav a:hover::after { transform: scaleX(1); }

/* Active state (for current page) */
.global-nav a.is-current::after {
  transform: scaleX(1);
  background: var(--color-primary-dark);
}
.global-nav a.is-current { color: var(--color-primary-dark); }

/* Dropdown */
.nav-has-sub { position: relative; }
.nav-sub {
  position: absolute;
  top: 100%; left: 50%;
  transform: translateX(-50%) translateY(8px);
  background: #fff;
  border: 1px solid var(--color-line-soft);
  min-width: 240px;
  padding: 14px 0;
  opacity: 0;
  visibility: hidden;
  transition: all .3s ease;
  box-shadow: 0 24px 50px rgba(44, 62, 80, 0.08);
}
.nav-has-sub:hover .nav-sub {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.nav-sub a {
  display: block;
  padding: 10px 24px;
  font-size: 13px;
  white-space: nowrap;
}
.nav-sub a::after { display: none; }
.nav-sub a:hover { background: var(--color-bg-secondary); }

/* Hamburger button (mobile) */
.hamburger {
  width: 36px;
  height: 36px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-end;
  gap: 7px;
  z-index: 105;
}
.hamburger span {
  display: block;
  height: 1.5px;
  background: var(--color-text-primary);
  transition: transform .35s ease, width .35s ease, opacity .35s ease;
}
.hamburger span:nth-child(1) { width: 28px; }
.hamburger span:nth-child(2) { width: 20px; }
.hamburger.is-open span:nth-child(1) {
  transform: translateY(4.5px) rotate(45deg);
  width: 28px;
}
.hamburger.is-open span:nth-child(2) {
  transform: translateY(-4.5px) rotate(-45deg);
  width: 28px;
}

@media (min-width: 1100px) {
  .header-top { display: block; }
  .global-nav { display: block; }
  .header-cta { display: flex; }
  .hamburger { display: none; }
}


/* ============================================================
   08. Mobile Navigation (drawer)
   ============================================================ */
.mobile-nav {
  position: fixed;
  inset: 0;
  background: #fff;
  padding: 90px 32px 40px;
  z-index: 99;
  transform: translateX(100%);
  transition: transform .45s cubic-bezier(.6, .05, .3, 1);
  overflow-y: auto;
}
.mobile-nav.is-open { transform: translateX(0); }
.mobile-nav > ul > li {
  border-bottom: 1px solid var(--color-line-soft);
}
.mobile-nav > ul > li > a,
.mobile-nav > ul > li > span {
  display: block;
  padding: 18px 0;
  font-family: var(--font-serif-jp);
  font-size: 16px;
  letter-spacing: 0.08em;
  font-weight: 500;
}
.mobile-nav .nav-sub-mobile {
  padding: 0 0 16px 0;
}
.mobile-nav .nav-sub-mobile a {
  display: block;
  padding: 8px 0 8px 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
}
.mobile-nav-info {
  margin-top: 40px;
  padding-top: 28px;
  border-top: 1px solid var(--color-line-soft);
}
.mobile-nav-info .phone-num {
  font-family: var(--font-serif-en);
  font-size: 28px;
  letter-spacing: 0.04em;
  font-weight: 500;
  display: block;
  margin-bottom: 6px;
  color: var(--color-text-primary);
}
.mobile-nav-info p {
  font-size: 12px;
  color: var(--color-text-secondary);
}
.mobile-nav-info .btn-reserve {
  width: 100%;
  margin-top: 24px;
  padding: 16px;
}

@media (min-width: 1100px) {
  .mobile-nav { display: none; }
}


/* ============================================================
   09. Footer
   ============================================================ */
.site-footer {
  background: var(--color-primary-deep);
  color: rgba(255, 255, 255, 0.7);
  padding: 80px 0 30px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}
@media (min-width: 900px) {
  .footer-top {
    grid-template-columns: 1.6fr 1fr 1fr 1fr;
    gap: 48px;
  }
}

.footer-brand .logo-mark {
  color: #fff;
  font-size: 26px;
}
.footer-brand .logo-mark span { color: var(--color-primary-light); }
.footer-brand .logo-sub { color: rgba(255, 255, 255, 0.4); }
.footer-brand p {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.55);
  margin-top: 24px;
  line-height: 2;
}

.footer-col h4 {
  font-family: var(--font-serif-en);
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--color-primary-light);
  font-weight: 500;
  margin-bottom: 22px;
  text-transform: uppercase;
}
.footer-col li {
  font-size: 12.5px;
  margin-bottom: 12px;
  letter-spacing: 0.04em;
}
.footer-col li a { color: rgba(255, 255, 255, 0.7); }
.footer-col li a:hover {
  color: var(--color-primary-light);
  opacity: 1;
}

.footer-bottom {
  padding-top: 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  font-size: 11px;
  color: rgba(255, 255, 255, 0.35);
  letter-spacing: 0.06em;
}
@media (min-width: 700px) {
  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

.footer-sns {
  display: flex;
  gap: 12px;
}
.footer-sns a {
  width: 36px;
  height: 36px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .3s ease;
}
.footer-sns a:hover {
  border-color: var(--color-primary-light);
  background: var(--color-primary-light);
  opacity: 1;
}
.footer-sns svg {
  width: 14px;
  height: 14px;
  fill: rgba(255, 255, 255, 0.6);
}
.footer-sns a:hover svg { fill: var(--color-primary-deep); }


/* ============================================================
   10. Fixed Bottom-Right CTA
   ============================================================ */
.fixed-cta {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: flex-end;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: opacity .5s ease, transform .5s ease;
}
.fixed-cta.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.fixed-cta-main {
  background: var(--color-primary-dark);
  color: #fff;
  padding: 16px 22px;
  font-size: 12px;
  letter-spacing: 0.14em;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  box-shadow: 0 16px 40px rgba(44, 62, 80, 0.3);
  transition: all .3s ease;
}
.fixed-cta-main:hover {
  background: var(--color-primary-deep);
  opacity: 1;
  transform: translateY(-2px);
}
.fixed-cta-main svg {
  width: 16px;
  height: 16px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.8;
}

.fixed-cta-options {
  display: none;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 4px;
}
.fixed-cta.is-open .fixed-cta-options { display: flex; }
.fixed-cta-options a {
  background: #fff;
  padding: 11px 18px;
  font-size: 12px;
  letter-spacing: 0.1em;
  border: 1px solid var(--color-line);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 10px 28px rgba(44, 62, 80, 0.12);
  transition: all .25s ease;
}
.fixed-cta-options a:hover {
  background: var(--color-bg-secondary);
  opacity: 1;
}
.fixed-cta-options a.is-line {
  background: #06C755;
  color: #fff;
  border-color: #06C755;
}
.fixed-cta-options a.is-line:hover { background: #05B348; }

@media (max-width: 700px) {
  .fixed-cta { right: 12px; bottom: 12px; }
  .fixed-cta-main {
    padding: 14px 18px;
    font-size: 11px;
  }
}


/* ============================================================
   11. Breadcrumbs (for lower pages)
   ============================================================ */
.breadcrumbs {
  padding: 16px 0;
  background: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-line-soft);
}
.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
}
.breadcrumbs li {
  display: flex;
  align-items: center;
  gap: 10px;
}
.breadcrumbs li + li::before {
  content: "/";
  color: var(--color-line);
  font-family: var(--font-serif-en);
  font-size: 12px;
}
.breadcrumbs a {
  color: var(--color-text-secondary);
}
.breadcrumbs a:hover {
  color: var(--color-primary-dark);
  opacity: 1;
}
.breadcrumbs [aria-current="page"] {
  color: var(--color-text-primary);
}


/* ============================================================
   12. Reveal Animation Utility (Scroll-triggered via IO)
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .9s ease, transform .9s ease;
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-d1 { transition-delay: .12s; }
.reveal-d2 { transition-delay: .24s; }
.reveal-d3 { transition-delay: .36s; }
.reveal-d4 { transition-delay: .48s; }


/* ============================================================
   13. Reduced Motion Override
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}