/* --- Global Reset & Basic Styles --- */
:root {
  --color-light-gray-base: #F0F0F0;
  --color-very-light-gray-panel: #F9F9F9;
  --color-medium-gray-text: #666666;
  --color-cool-gray-accent: #A9B3C1;
  --color-dark-text: #333333;
  --color-light-border: #DDDDDD;
  --header-height: 70px;
  --font-primary: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  margin: 0;
  font-family: var(--font-primary);
  background-color: var(--color-light-gray-base);
  color: var(--color-medium-gray-text);
  line-height: 1.7;
  overflow-x: hidden;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

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

section {
  padding: 5rem 2rem;
  text-align: center;
  border-bottom: 1px solid var(--color-light-border);
}
section:last-of-type {
  border-bottom: none;
}
section#hero {
  background-color: var(--color-light-gray-base);
  padding-top: var(--header-height);
}
section:not(#hero):nth-of-type(odd) {
   background-color: var(--color-very-light-gray-panel);
}
section:not(#hero):nth-of-type(even) {
   background-color: var(--color-light-gray-base);
}

h1, h2, h3 { /* h1のスタイルも共通部分をこちらへ */
  color: var(--color-cool-gray-accent);
  font-weight: 600;
  line-height: 1.3; /* h1にも適用されるように共通化 */
}

h2 { /* セクションタイトル用 (index.html側で class="section-title" があれば不要) */
  font-size: 2.5rem;
  margin-bottom: 2.5rem;
  letter-spacing: 1px;
}

p {
  margin-bottom: 1rem;
  font-size: 1rem;
  color: var(--color-medium-gray-text);
}

.container {
  max-width: 800px;
  margin: 0 auto;
  padding-left: 1rem; /* スマホ表示で左右に余白がない場合のため */
  padding-right: 1rem;
}
@media (min-width: 851px) { /* PCでは .container の左右パディングは不要な場合も */
  .container {
      padding-left: 0;
      padding-right: 0;
  }
}


/* --- Header --- */
.header {
  background-color: var(--color-very-light-gray-panel);
  padding: 0 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  height: var(--header-height);
  border-bottom: 1px solid var(--color-light-border);
}

.logo {
  flex-shrink: 0;
}
.logo h1 { /* h1タグに直接スタイルを適用 */
  margin-bottom: 0; /* h1共通スタイルからリセット */
}
.logo h1 a {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-dark-text);
  text-decoration: none;
}

.header-right-content {
  display: flex;
  align-items: center;
}

/* Desktop Navigation */
.desktop-nav {
  display: none; /* Default: hidden (mobile-first) */
}
.desktop-nav ul {
  display: flex;
  align-items: center;
  /* list-style: none; は ul リセットで対応済み */
  /* padding: 0; margin: 0; は * リセットで対応済み */
}
.desktop-nav ul li {
  margin-left: 1.5rem;
}
.desktop-nav ul li:first-child {
  margin-left: 0;
}
.desktop-nav ul li a {
  /* text-decoration: none; は a リセットで対応済み */
  color: var(--color-medium-gray-text);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 0.5rem 0.2rem;
  white-space: nowrap;
  transition: color 0.3s ease;
}
.desktop-nav ul li a:hover {
  color: var(--color-cool-gray-accent);
}

/* Desktop Navigation Dropdown */
.desktop-nav ul li.dropdown-menu-item {
  position: relative;
}
/* .desktop-nav ul li.dropdown-menu-item > a {} は特に不要であれば削除 */
.desktop-nav ul li.dropdown-menu-item .dropdown-content {
  display: none;
  position: absolute;
  top: 100%; /* 親メニューの高さに依存 */
  left: 0;
  background-color: var(--color-very-light-gray-panel);
  min-width: 200px;
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
  z-index: 1001;
  border: 1px solid var(--color-light-border);
  border-top: none;
  padding: 0.5rem 0;
  border-radius: 0 0 6px 6px;
}
.desktop-nav ul li.dropdown-menu-item:hover .dropdown-content,
.desktop-nav ul li.dropdown-menu-item .dropdown-content:hover {
  display: block;
}
.desktop-nav .dropdown-content li a {
  /* color: var(--color-medium-gray-text); /* 親から継承 */
  padding: 0.8rem 1.2rem;
  /* text-decoration: none; /* 親から継承 */
  display: block;
  text-align: left;
  /* white-space: nowrap; /* 親から継承の可能性 */
  font-size: 0.9rem;
  font-weight: normal;
}
.desktop-nav .dropdown-content li a:hover {
  background-color: var(--color-light-border);
  color: var(--color-dark-text);
}


/* Social Links */
.social-links {
  display: flex;
  align-items: center;
}
.social-link {
  display: inline-block;
  padding: 6px;
}
.social-icon-svg {
  width: 26px;
  height: 26px;
  fill: var(--color-medium-gray-text);
  transition: fill 0.3s ease, transform 0.2s ease;
  display: block; /* aタグ内で中央揃えしやすくするため */
}
.social-icon-svg:hover {
  fill: var(--color-cool-gray-accent);
  transform: scale(1.1);
}

/* Hamburger Menu Icon */
.hamburger-icon {
  display: block; /* Default for mobile */
  cursor: pointer;
  padding: 10px; /* クリックエリアの確保 */
  margin: -10px -10px -10px 0.5rem; /* パディングによるズレを相殺、左マージンでSNSリンクとの間隔 */
  z-index: 1005;
}
.hamburger-icon .bar {
  display: block;
  width: 28px;
  height: 3px;
  margin: 5px auto;
  background-color: var(--color-dark-text);
  transition: all 0.3s ease-in-out;
  border-radius: 1px;
}
.hamburger-icon.active .bar:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.hamburger-icon.active .bar:nth-child(2) { opacity: 0; }
.hamburger-icon.active .bar:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* Media Queries for Navigation Visibility */
@media (min-width: 851px) {
  .header {
      padding: 0 2.5rem;
  }
  .logo h1 a {
      font-size: 1.8rem;
  }
  .desktop-nav {
      display: flex !important;
  }
  .social-links {
      margin-left: 1.8rem;
  }
  .social-icon-svg {
      width: 22px;
      height: 22px;
  }
  .social-link {
      padding: 8px;
  }
  .hamburger-icon {
      display: none !important;
  }
  .mobile-nav, .mobile-nav.active {
      display: none !important;
  }
}
@media (max-width: 850px) {
  .desktop-nav {
      display: none !important;
  }
  .hamburger-icon {
      display: block !important;
  }
  /* .social-links positioning is handled by .header-right-content flex */
}

/* Mobile Navigation Panel */
.mobile-nav {
  display: none;
  position: fixed;
  top: var(--header-height);
  left: 0;
  width: 100%;
  background-color: var(--color-very-light-gray-panel);
  z-index: 999;
  border-bottom: 1px solid var(--color-light-border);
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}
.mobile-nav.active {
  display: block;
  max-height: calc(100vh - var(--header-height));
  overflow-y: auto;
}
.mobile-nav ul { /* Resetで対応済み */ }
.mobile-nav ul li a {
  display: block;
  padding: 1rem 2rem;
  text-align: center;
  border-bottom: 1px solid var(--color-light-border);
  font-size: 1.1rem;
  color: var(--color-medium-gray-text);
  transition: background-color 0.3s ease, color 0.3s ease;
}
.mobile-nav ul li:last-child a { border-bottom: none; }
.mobile-nav ul li a:hover {
  background-color: var(--color-light-border);
  color: var(--color-cool-gray-accent);
}
/* Mobile Navigation Dropdown */
.mobile-nav ul li.dropdown-menu-item-mobile .portfolio-toggle-mobile .arrow-down {
  display: inline-block;
  margin-left: 0.5em;
  font-size: 0.8em;
  transition: transform 0.3s ease;
}
.mobile-nav ul li.dropdown-menu-item-mobile.open .portfolio-toggle-mobile .arrow-down {
  transform: rotate(180deg);
}
.mobile-nav .dropdown-content-mobile {
  display: none; /* JS controls this */
  background-color: var(--color-light-gray-base);
}
.mobile-nav .dropdown-content-mobile li a {
  font-size: 1rem;
  padding: 0.8rem 2rem 0.8rem 3rem; /* Indent submenu items */
  /* text-align: center; /* Inherited */
  /* border-bottom: 1px solid var(--color-light-border); /* Inherited */
}
/* .mobile-nav .dropdown-content-mobile li:last-child a { border-bottom: none; } /* Inherited */


/* --- Main Content Sections --- */
.main-content {
  padding-top: var(--header-height);
}

/* Hero Section */
#hero {
  min-height: calc(100vh - var(--header-height));
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.hero-content {
   max-width: 900px;
   padding: 2rem;
}
.hero-title span,
.hero-description span {
  display: inline-block;
  opacity: 0;
  transform: translateY(25px);
}
@keyframes fadeInSlideUp { /* Used by hero text */
  to {
      opacity: 1;
      transform: translateY(0);
  }
}
.hero-title span:nth-of-type(1) { animation: fadeInSlideUp 0.8s ease-out 0.3s forwards; }
.hero-title span:nth-of-type(2) { animation: fadeInSlideUp 0.8s ease-out 0.6s forwards; }
.hero-description span:nth-of-type(1) { animation: fadeInSlideUp 0.8s ease-out 0.9s forwards; }
.hero-description span:nth-of-type(2) { animation: fadeInSlideUp 0.8s ease-out 1.2s forwards; }

.hero-content h1 { /* h1のスタイルは共通化 */
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  margin-bottom: 1.5rem; /* h2の共通スタイルから分離 */
  font-weight: 700; /* h1,h2,h3の共通スタイルから分離・強調 */
}
.hero-content p {
  font-size: clamp(1rem, 2.5vw, 1.3rem);
}

/* Concept Section */
#concept p {
  font-size: 1.1rem;
  line-height: 1.8;
}

/* --- Portfolio Section --- */
/* --- Portfolio Section (Webサイト and Webアプリ共通) --- */
#portfolio-websites,
#portfolio-webapps { 
    overflow-x: hidden; 
}

.portfolio-slider-container {
    position: relative;
    width: 100%; 
    max-width: 1200px; 
    margin: 2rem auto;
    padding: 0 50px; 
    box-sizing: border-box;
}

.portfolio-slider-wrapper {
    width: 100%;
    overflow: hidden; 
    position: relative;
}

.portfolio-slider {
    display: flex; 
    position: relative; 
    transition: transform 0.5s ease-in-out;
}

.portfolio-item { 
    flex-shrink: 0; 
    box-sizing: border-box;
    padding: 0 0.75rem; 
    /* width is set by JS */
}
/* Responsive widths for .portfolio-item (these are initial states, JS might override width directly) */
@media (min-width: 992px) { 
    #portfolio-websites .portfolio-item, 
    #portfolio-webapps .portfolio-item { width: calc(100% / 3); }
}
@media (min-width: 600px) and (max-width: 991px) { 
    #portfolio-websites .portfolio-item, 
    #portfolio-webapps .portfolio-item { width: 50%; }
}
@media (max-width: 599px) { 
    #portfolio-websites .portfolio-item, 
    #portfolio-webapps .portfolio-item { width: 100%; }
}


.portfolio-item a {
    display: block;
    border: 1px solid var(--color-light-border);
    border-radius: 8px;
    overflow: hidden;
    background-color: var(--color-very-light-gray-panel);
    transition: box-shadow 0.3s ease;
    height: 100%; 
}
.portfolio-item a:hover {
    box-shadow: 0 8px 20px rgba(169, 179, 193, 0.15);
}

.portfolio-item img {
    width: 100%;
    height: 220px; /* 基本の高さを維持 */
    object-fit: cover; /* デフォルトはカバー */
    display: block; /* display: block を追加 */
    background-color: var(--color-light-gray-base); /* 画像が小さい場合の背景色 */
}

/* ★ モバイル表示時の画像表示調整 ★ */
@media (max-width: 599px) { /* モバイル（1列表示）のブレークポイント */
    .portfolio-item img {
        object-fit: contain; /* ★ 画像全体が表示されるように変更 */
        height: 200px;       /* ★ モバイルでは高さを少し調整（任意） */
                               /* または height: auto; にして画像の縦横比に任せる */
    }
    /* もしWebアプリのサムネイルだけ挙動を変えたい場合 */
    /* .portfolio-item.webapp-item img {
        object-fit: contain;
        height: 180px; 
    } */
}


.portfolio-item h3 {
    padding: 1rem 1.2rem;
    font-size: 1.1rem;
    background-color: var(--color-light-border);
    margin: 0; 
    min-height: 3.5em; 
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-cool-gray-accent); /* h3の共通スタイルから継承されるが明示 */
    font-weight: 600; /* h3の共通スタイルから継承されるが明示 */
}

/* ... (以降の .slider-controls, .slider-btn, .portfolio-description などは変更なし) ... */

.slider-controls {
  position: static; 
  text-align: center;
  margin-top: 1.5rem;
}
.slider-btn {
  position: absolute; 
  top: 50%;
  transform: translateY(-50%);
  background: var(--color-light-border);
  border: none;
  font: bold 1.8rem / 1 var(--font-primary); 
  color: var(--color-cool-gray-accent);
  cursor: pointer;
  padding: 0.5rem 0.8rem; 
  z-index: 10;
  border-radius: 50%; 
  width: 40px; 
  height: 40px; 
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.3s ease, transform 0.2s ease;
}
.slider-btn:hover {
  background: var(--color-medium-gray-text);
  color: var(--color-light-gray-base);
  transform: translateY(-50%) scale(1.1); 
}
.slider-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
  transform: translateY(-50%) scale(1); 
}
.prev-btn { left: 10px; }
.next-btn { right: 10px; }

.portfolio-description {
  margin-top: 2rem;
  font-size: 0.9rem;
}
.portfolio-description .view-all-link {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.5rem 1rem;
  color: var(--color-cool-gray-accent);
  border: 1px solid var(--color-cool-gray-accent);
  border-radius: 4px;
  transition: background-color 0.3s ease, color 0.3s ease;
  font-weight: 500;
}
.portfolio-description .view-all-link:hover {
  background-color: var(--color-cool-gray-accent);
  color: var(--color-very-light-gray-panel);
}

/* Profile Section */
.profile-info {
  max-width: 700px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.profile-icon-wrapper {
  width: 150px;
  height: 150px;
  border-radius: 50%;
  overflow: hidden;
  margin-bottom: 2rem;
  border: 4px solid var(--color-cool-gray-accent);
  box-shadow: 0 0 15px rgba(169, 179, 193, 0.2);
}
.profile-icon-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.profile-info h3 { /* h3のスタイルは共通化 */
  font-size: 2rem;
  margin-bottom: 1rem;
  font-weight: 700; /* 強調 */
}
.profile-info p {
  font-size: 1.1rem;
  line-height: 1.8;
}

/* Contact Section */
#contact .container p {
  margin-bottom: 2.5rem;
}
#contactForm {
  max-width: 700px;
  margin: 0 auto;
  text-align: left;
  padding: 2.5rem;
  border: 1px solid var(--color-light-border);
  border-radius: 10px;
  background-color: var(--color-very-light-gray-panel);
}
.form-group {
  margin-bottom: 1.8rem;
}
.form-group label {
  display: block;
  margin-bottom: 0.75rem;
  color: var(--color-cool-gray-accent);
  font-size: 1rem;
  font-weight: 500;
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 1rem;
  border: 1px solid var(--color-light-border);
  border-radius: 5px;
  font-size: 1rem;
  background-color: var(--color-light-gray-base);
  color: var(--color-medium-gray-text);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}
.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-cool-gray-accent);
  box-shadow: 0 0 8px rgba(169, 179, 193, 0.25);
}
.submit-btn {
  background-color: var(--color-cool-gray-accent);
  color: var(--color-very-light-gray-panel);
  padding: 1rem 2rem;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1.1rem;
  font-weight: 600;
  transition: background-color 0.3s ease, color 0.3s ease, transform 0.2s ease;
  width: 100%;
  text-transform: uppercase;
  letter-spacing: 1px;
}
.submit-btn:hover {
  background-color: var(--color-medium-gray-text);
  color: var(--color-light-gray-base);
  transform: translateY(-2px);
}
.form-response {
  margin-top: 1.5rem;
  padding: 1rem;
  border-radius: 5px;
  font-weight: 500;
  text-align: center;
  display: none;
}
.form-response.success {
  background-color: rgba(169, 179, 193, 0.1);
  color: #388e3c; 
  border: 1px solid #388e3c;
}
.form-response.error {
  background-color: rgba(169, 179, 193, 0.1);
  color: #d32f2f; 
  border: 1px solid #d32f2f;
}

/* Footer */
.footer {
  background-color: var(--color-very-light-gray-panel);
  color: var(--color-medium-gray-text);
  text-align: center;
  padding: 2rem;
  border-top: 1px solid var(--color-light-border);
  font-size: 0.9rem;
}

/* General Mobile Adjustments */
@media (max-width: 768px) { 
  h2 { font-size: 1.8rem; } /* General h2 adjustments for mobile */
  section { padding: 3rem 1rem; }
  .hero-content h1 { font-size: 2rem; }
  .hero-content p { font-size: 1rem; }
  .container { /* スマホではコンテナの左右パディングを少し増やす */
      padding-left: 1.5rem;
      padding-right: 1.5rem;
  }
}

/* --- webapp_usage.html 専用スタイル --- */
/* .webapp-usage-main, .webapp-usage-section, .page-title-usage は既存のままでOK */

.app-description-group {
  margin-bottom: 5.5rem; /* ★ コンテナ間のスペースを4remから5.5remに少し広げました */
  padding: 2rem;
  background-color: var(--color-very-light-gray-panel);
  border: 1px solid var(--color-light-border);
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
.app-description-group h2 { /* 各アプリ名 */
  font-size: 2rem; 
  color: var(--color-dark-text);
  margin-bottom: 1.5rem;
  text-align: center; 
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-light-border);
}

.app-description-group .usage-steps { /* ★ 追加: 使い方のステップ全体を囲む要素のスタイル */
  text-align: left; /* ★ ステップのテキスト全体を左寄せに */
}
.app-description-group .usage-steps p,
.app-description-group .usage-steps li {
  margin-bottom: 0.75rem;
  line-height: 1.8;
  color: var(--color-medium-gray-text);
  /* text-align: left; は親の .usage-steps から継承されます */
}
.app-description-group .usage-steps ul,
.app-description-group .usage-steps ol {
  margin-left: 1.5rem; 
  margin-bottom: 1rem;
  padding-left: 1.5rem; /* リストマーカーのためのスペースを調整 */
}
.app-description-group .usage-steps ul li { list-style-type: disc; }
.app-description-group .usage-steps ol li { list-style-type: decimal; }

.app-link-button-container {
  text-align: center;
  margin-top: 2.5rem; /* ★ ボタン上のマージンを少し広げました */
}
.app-link-button {
  display: inline-block;
  padding: 0.9rem 2.2rem; /* パディングを少し調整 */
  background-color: var(--color-dark-text); /* ★ ボタン背景色を濃いグレーに変更 */
  color: var(--color-very-light-gray-panel);   /* ★ ボタン文字色を非常に明るいグレーに変更 */
  text-decoration: none;
  border-radius: 6px; /* 少し丸みを調整 */
  font-weight: 600;
  transition: background-color 0.3s ease, transform 0.2s ease; /* transformも追加 */
  font-size: 1.1rem; /* 文字サイズは変更なし */
  letter-spacing: 0.5px; /* 少し文字間隔を調整 (任意) */
  border: 1px solid transparent; /* ホバー時のボーダー変化に備える (任意) */
}
.app-link-button:hover {
  background-color: var(--color-medium-gray-text); /* ★ ホバー時の背景色を少し明るい濃いグレーに */
  color: var(--color-very-light-gray-panel);       /* 文字色は維持 */
  transform: translateY(-2px); /* 少し浮き上がるエフェクト */
  /* border-color: var(--color-cool-gray-accent); */ /* ホバー時にアクセントカラーのボーダー (任意) */
}

/* --- (既存のフッターなどのスタイルは変更なし) --- */