/* ==========================================================================
   MyBlog Material Design 3 (Material You) Design System
   - 彩度を持たないモノトーン。強調は色ではなく明度差とエレベーションで付ける
   - ライト / ダーク (body.dark-mode) の両スキームを同一トークン名で切り替える
   ========================================================================== */

:root {
  /* --- Color roles: Light scheme --- */
  --md-primary: #1a1a1a;
  --md-on-primary: #ffffff;
  --md-primary-container: #e0e0e0;
  --md-on-primary-container: #1a1a1a;

  --md-secondary: #4a4a4a;
  --md-on-secondary: #ffffff;
  --md-secondary-container: #ececec;
  --md-on-secondary-container: #1f1f1f;

  --md-tertiary: #5f5f5f;
  --md-on-tertiary: #ffffff;
  --md-tertiary-container: #e6e6e6;
  --md-on-tertiary-container: #1f1f1f;

  /* 破壊的操作もモノトーンで表す。他のボタンより濃いグレー + アウトラインで区別する */
  --md-error: #2a2a2a;
  --md-on-error: #ffffff;
  --md-error-container: #d6d6d6;
  --md-on-error-container: #1a1a1a;

  --md-background: #ffffff;
  --md-on-background: #1a1a1a;
  --md-surface: #ffffff;
  --md-on-surface: #1a1a1a;
  --md-surface-variant: #e4e4e4;
  --md-on-surface-variant: #4a4a4a;

  --md-surface-container-lowest: #ffffff;
  --md-surface-container-low: #f8f8f8;
  --md-surface-container: #f2f2f2;
  --md-surface-container-high: #ececec;
  --md-surface-container-highest: #e6e6e6;

  --md-outline: #767676;
  --md-outline-variant: #c6c6c6;

  --md-inverse-surface: #303030;
  --md-inverse-on-surface: #f2f2f2;
  --md-inverse-primary: #e0e0e0;
  --md-scrim: 0, 0, 0;

  /* ステートレイヤー用の RGB 値 (rgba() 合成に使う) */
  --md-primary-rgb: 26, 26, 26;
  --md-on-surface-rgb: 26, 26, 26;
  --md-error-rgb: 42, 42, 42;

  /* --- Elevation --- */
  --md-elevation-1: 0 1px 2px rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.15);
  --md-elevation-2: 0 1px 2px rgba(0, 0, 0, 0.3), 0 2px 6px 2px rgba(0, 0, 0, 0.15);
  --md-elevation-3: 0 1px 3px rgba(0, 0, 0, 0.3), 0 4px 8px 3px rgba(0, 0, 0, 0.15);
  --md-elevation-4: 0 2px 3px rgba(0, 0, 0, 0.3), 0 6px 10px 4px rgba(0, 0, 0, 0.15);
  --md-elevation-5: 0 4px 4px rgba(0, 0, 0, 0.3), 0 8px 12px 6px rgba(0, 0, 0, 0.15);

  /* --- Shape (角丸) --- */
  --md-shape-xs: 4px;
  --md-shape-sm: 8px;
  --md-shape-md: 12px;
  --md-shape-lg: 16px;
  --md-shape-xl: 28px;
  --md-shape-full: 9999px;

  /* --- Motion --- */
  --md-easing-standard: cubic-bezier(0.2, 0, 0, 1);
  --md-easing-emphasized: cubic-bezier(0.2, 0, 0, 1);
  --md-duration-short: 100ms;
  --md-duration-medium: 200ms;
  --md-duration-long: 350ms;

  /* --- Typography --- */
  --md-font-plain: 'Roboto', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI',
    'Hiragino Sans', 'Hiragino Kaku Gothic ProN', 'Yu Gothic', 'Meiryo', sans-serif;
  --md-font-mono: 'Roboto Mono', 'SF Mono', Monaco, Consolas, 'Courier New', monospace;
}

/* head 内のインラインスクリプトが html に theme-dark-pending を付けることで
   初回描画前からダークスキームを適用する (index.js が body.dark-mode に引き継ぐ) */
body.dark-mode,
.theme-dark-pending body {
  /* --- Color roles: Dark scheme --- */
  --md-primary: #e3e3e3;
  --md-on-primary: #1a1a1a;
  --md-primary-container: #4a4a4a;
  --md-on-primary-container: #ececec;

  --md-secondary: #c6c6c6;
  --md-on-secondary: #2a2a2a;
  --md-secondary-container: #3a3a3a;
  --md-on-secondary-container: #e6e6e6;

  --md-tertiary: #b8b8b8;
  --md-on-tertiary: #2f2f2f;
  --md-tertiary-container: #454545;
  --md-on-tertiary-container: #e6e6e6;

  --md-error: #d6d6d6;
  --md-on-error: #2a2a2a;
  --md-error-container: #4f4f4f;
  --md-on-error-container: #ececec;

  --md-background: #121212;
  --md-on-background: #e6e6e6;
  --md-surface: #121212;
  --md-on-surface: #e6e6e6;
  --md-surface-variant: #454545;
  --md-on-surface-variant: #c6c6c6;

  --md-surface-container-lowest: #0d0d0d;
  --md-surface-container-low: #1a1a1a;
  --md-surface-container: #1e1e1e;
  --md-surface-container-high: #282828;
  --md-surface-container-highest: #333333;

  --md-outline: #919191;
  --md-outline-variant: #454545;

  --md-inverse-surface: #e6e6e6;
  --md-inverse-on-surface: #303030;
  --md-inverse-primary: #1a1a1a;

  --md-primary-rgb: 227, 227, 227;
  --md-on-surface-rgb: 230, 230, 230;
  --md-error-rgb: 214, 214, 214;
}

/* ==========================================================================
   Base
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--md-font-plain);
  background-color: var(--md-background);
  color: var(--md-on-background);
  line-height: 1.7;
  letter-spacing: 0.01em;
  margin: 0;
  padding: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--md-duration-long) var(--md-easing-standard),
    color var(--md-duration-long) var(--md-easing-standard);
}

.container,
.container-fluid {
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 24px;
}

body > .container {
  flex: 1 0 auto;
  padding-bottom: 32px;
}

section {
  background: transparent !important;
  padding: 8px 0 24px;
}

/* --- Typography scale --- */
.md-display-small,
.display-3 {
  font-size: 2.25rem;
  line-height: 1.25;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--md-on-background);
  margin: 40px 0 8px;
}

.md-headline-small,
h1 {
  font-size: 1.75rem;
  line-height: 1.3;
  font-weight: 500;
  letter-spacing: 0;
}

h2 {
  font-size: 1.5rem;
  line-height: 1.35;
  font-weight: 500;
  letter-spacing: 0;
}

h3 {
  font-size: 1.25rem;
  line-height: 1.4;
  font-weight: 500;
}

.md-body-large {
  font-size: 1rem;
  line-height: 1.5;
  letter-spacing: 0.031em;
}

.md-label-large {
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.006em;
}

.text-muted,
.md-supporting-text {
  color: var(--md-on-surface-variant) !important;
  font-size: 0.8125rem;
  line-height: 1.4;
  letter-spacing: 0.025em;
}

a {
  color: var(--md-primary);
  text-decoration: none;
  transition: color var(--md-duration-medium) var(--md-easing-standard);
}

a:hover {
  text-decoration: underline;
}

hr {
  border: 0;
  border-top: 1px solid var(--md-outline-variant);
  margin: 32px 0;
  opacity: 1;
}

:focus-visible {
  outline: 3px solid var(--md-primary);
  outline-offset: 2px;
}

/* ==========================================================================
   State layer / Ripple
   ========================================================================== */

.md-state-layer {
  position: relative;
  overflow: hidden;
  isolation: isolate;
}

.md-state-layer::before {
  content: '';
  position: absolute;
  inset: 0;
  background-color: currentColor;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--md-duration-medium) var(--md-easing-standard);
  z-index: 0;
}

.md-state-layer:hover::before {
  opacity: 0.08;
}

.md-state-layer:focus-visible::before {
  opacity: 0.1;
}

.md-state-layer:active::before {
  opacity: 0.1;
}

.md-state-layer > * {
  position: relative;
  z-index: 1;
}

.md-ripple {
  position: absolute;
  border-radius: 50%;
  transform: scale(0);
  background-color: currentColor;
  opacity: 0.24;
  pointer-events: none;
  animation: md-ripple-expand 500ms var(--md-easing-standard) forwards;
  z-index: 0;
}

@keyframes md-ripple-expand {
  to {
    transform: scale(2.4);
    opacity: 0;
  }
}

/* ==========================================================================
   Top app bar
   ========================================================================== */

.header {
  position: sticky;
  top: 0;
  z-index: 100;
  width: 100%;
  background-color: var(--md-surface-container);
  color: var(--md-on-surface);
  box-shadow: none;
  transition: box-shadow var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-long) var(--md-easing-standard);
}

/* スクロール時に "on scroll" エレベーションを付与 (index.js が付ける) */
.header.is-scrolled {
  box-shadow: var(--md-elevation-2);
  background-color: var(--md-surface-container-high);
}

.navbar {
  background: transparent !important;
  padding: 0;
  width: 100%;
}

.md-top-app-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 64px;
}

.navbar-brand {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 1.375rem;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--md-on-surface);
  text-decoration: none;
  padding: 8px 12px;
  border-radius: var(--md-shape-full);
  transition: background-color var(--md-duration-medium) var(--md-easing-standard);
}

.navbar-brand:hover {
  text-decoration: none;
  color: var(--md-on-surface);
  background-color: rgba(var(--md-on-surface-rgb), 0.08);
}

.md-top-app-bar .nav-link {
  position: relative;
  overflow: hidden;
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.006em;
  color: var(--md-on-surface-variant);
  padding: 10px 16px;
  border-radius: var(--md-shape-full);
  transition: background-color var(--md-duration-medium) var(--md-easing-standard),
    color var(--md-duration-medium) var(--md-easing-standard);
}

.md-top-app-bar .nav-link:hover {
  text-decoration: none;
  color: var(--md-on-surface);
  background-color: rgba(var(--md-on-surface-rgb), 0.08);
}

.md-top-app-bar .md-spacer {
  margin-left: auto;
}

/* --- Icon button --- */
.md-icon-button,
.dark-mode-toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  flex: 0 0 auto;
  padding: 0;
  border: none;
  border-radius: var(--md-shape-full);
  background-color: transparent;
  color: var(--md-on-surface-variant);
  cursor: pointer;
  overflow: hidden;
  transition: background-color var(--md-duration-medium) var(--md-easing-standard),
    color var(--md-duration-medium) var(--md-easing-standard);
}

.md-icon-button:hover,
.dark-mode-toggle:hover {
  background-color: rgba(var(--md-on-surface-rgb), 0.08);
  color: var(--md-on-surface);
}

.md-icon-button:active,
.dark-mode-toggle:active {
  background-color: rgba(var(--md-on-surface-rgb), 0.12);
}

.dark-mode-toggle svg {
  position: absolute;
  transition: opacity var(--md-duration-long) var(--md-easing-standard),
    transform var(--md-duration-long) var(--md-easing-standard);
  color: inherit;
}

.dark-mode-toggle .sun-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

.dark-mode-toggle .moon-icon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.4);
}

body.dark-mode .dark-mode-toggle .sun-icon,
.theme-dark-pending body .dark-mode-toggle .sun-icon {
  opacity: 0;
  transform: rotate(90deg) scale(0.4);
}

body.dark-mode .dark-mode-toggle .moon-icon,
.theme-dark-pending body .dark-mode-toggle .moon-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

/* ==========================================================================
   Buttons
   ========================================================================== */

.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 40px;
  padding: 10px 24px;
  border: none;
  border-radius: var(--md-shape-full);
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.006em;
  line-height: 1.25rem;
  text-transform: none;
  text-decoration: none;
  cursor: pointer;
  overflow: hidden;
  background-color: var(--md-primary);
  color: var(--md-on-primary);
  box-shadow: none;
  transition: box-shadow var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-medium) var(--md-easing-standard),
    color var(--md-duration-medium) var(--md-easing-standard);
}

.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background-color: currentColor;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--md-duration-medium) var(--md-easing-standard);
}

.btn:hover::before {
  opacity: 0.08;
}

.btn:focus-visible::before,
.btn:active::before {
  opacity: 0.12;
}

.btn:hover {
  box-shadow: var(--md-elevation-1);
  text-decoration: none;
}

.btn:active {
  box-shadow: none;
}

.btn:disabled,
.btn.disabled {
  background-color: rgba(var(--md-on-surface-rgb), 0.12);
  color: rgba(var(--md-on-surface-rgb), 0.38);
  box-shadow: none;
  cursor: not-allowed;
  pointer-events: none;
}

/* Filled button (既定) */
.btn-primary,
.btn-filled {
  background-color: var(--md-primary);
  color: var(--md-on-primary);
}

.btn-primary:hover,
.btn-filled:hover {
  background-color: var(--md-primary);
  color: var(--md-on-primary);
}

/* Tonal button */
.btn-tonal,
.btn-secondary {
  background-color: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
}

.btn-tonal:hover,
.btn-secondary:hover {
  background-color: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
}

/* Outlined button */
.btn-outlined,
.btn-outline-secondary,
.btn-outline-primary {
  background-color: transparent;
  color: var(--md-primary);
  box-shadow: none;
  border: 1px solid var(--md-outline);
  padding: 9px 23px;
}

.btn-outlined:hover,
.btn-outline-secondary:hover,
.btn-outline-primary:hover {
  background-color: transparent;
  color: var(--md-primary);
  box-shadow: none;
  border-color: var(--md-primary);
}

/* Text button */
.btn-text {
  background-color: transparent;
  color: var(--md-primary);
  padding: 10px 12px;
  box-shadow: none;
}

.btn-text:hover {
  background-color: transparent;
  color: var(--md-primary);
  box-shadow: none;
}

/* Error / destructive */
.btn-danger,
.btn-outline-danger {
  background-color: var(--md-error-container);
  color: var(--md-on-error-container);
  border: 1px solid var(--md-outline);
  padding: 9px 23px;
}

.btn-danger:hover,
.btn-outline-danger:hover {
  background-color: var(--md-error-container);
  color: var(--md-on-error-container);
}

.btn-sm {
  min-height: 32px;
  padding: 6px 16px;
  font-size: 0.8125rem;
}

.action-buttons {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin: 24px 0 32px;
}

.action-buttons form {
  display: inline-flex;
  margin: 0;
}

/* ==========================================================================
   Cards
   ========================================================================== */

.row {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
  margin: 24px 0;
}

.col {
  display: contents;
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 152px;
  padding: 20px;
  margin: 0 0 4px;
  background-color: var(--md-surface-container-low);
  color: var(--md-on-surface);
  border: none;
  border-radius: var(--md-shape-md);
  box-shadow: var(--md-elevation-1);
  overflow: hidden;
  transition: box-shadow var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-long) var(--md-easing-standard);
  animation: md-fade-in-up var(--md-duration-long) var(--md-easing-standard) both;
}

.card:hover {
  box-shadow: var(--md-elevation-2);
  background-color: var(--md-surface-container);
}

.card-title {
  font-size: 1.125rem;
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0;
  color: var(--md-on-surface);
  margin: 0 0 12px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}

.card > div:last-child {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px solid var(--md-outline-variant);
}

/* カード内のアクション (Text button 相当) */
.card-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 6px 16px;
  margin: 0;
  border: none;
  border-radius: var(--md-shape-full);
  background-color: transparent;
  color: var(--md-primary);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.006em;
  text-decoration: none;
  overflow: hidden;
  transition: background-color var(--md-duration-medium) var(--md-easing-standard);
}

.card-link::before {
  content: '';
  position: absolute;
  inset: 0;
  background-color: currentColor;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--md-duration-medium) var(--md-easing-standard);
}

.card-link:hover {
  color: var(--md-primary);
  text-decoration: none;
}

.card-link:hover::before {
  opacity: 0.08;
}

.card-link:active::before {
  opacity: 0.12;
}

@keyframes md-fade-in-up {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ==========================================================================
   Chips (シリーズバッジなど)
   ========================================================================== */

.badge,
.md-chip {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 28px;
  padding: 0 12px;
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-sm);
  background-color: transparent !important;
  color: var(--md-on-surface-variant) !important;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.031em;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color var(--md-duration-medium) var(--md-easing-standard),
    color var(--md-duration-medium) var(--md-easing-standard),
    border-color var(--md-duration-medium) var(--md-easing-standard);
}

a.badge:hover,
a.md-chip:hover {
  background-color: var(--md-secondary-container) !important;
  color: var(--md-on-secondary-container) !important;
  border-color: transparent;
  text-decoration: none;
}

/* ==========================================================================
   Surfaces: 記事本文
   ========================================================================== */

.article-content {
  background-color: var(--md-surface-container-lowest);
  color: var(--md-on-surface);
  border: none;
  border-radius: var(--md-shape-lg);
  box-shadow: var(--md-elevation-1);
  padding: 28px 32px;
  margin: 20px 0 32px;
  line-height: 1.85;
  word-break: break-word;
  overflow-wrap: break-word;
  transition: background-color var(--md-duration-long) var(--md-easing-standard);
}

.article-content h1,
.article-content h2,
.article-content h3,
.article-content h4,
.article-content h5,
.article-content h6 {
  margin: 32px 0 12px;
  font-weight: 500;
  color: var(--md-on-surface);
  letter-spacing: 0;
}

.article-content > :first-child {
  margin-top: 0;
}

.article-content h2 {
  font-size: 1.375rem;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--md-outline-variant);
}

.article-content h3 {
  font-size: 1.125rem;
}

.article-content p {
  margin: 14px 0;
  color: var(--md-on-surface);
}

.article-content ul,
.article-content ol {
  margin: 14px 0;
  padding-left: 24px;
  color: var(--md-on-surface);
}

.article-content li {
  margin: 6px 0;
}

.article-content blockquote {
  margin: 20px 0;
  padding: 12px 20px;
  border: none;
  border-left: 4px solid var(--md-primary);
  border-radius: 0 var(--md-shape-sm) var(--md-shape-sm) 0;
  background-color: var(--md-surface-container-low);
  color: var(--md-on-surface-variant);
  font-style: normal;
}

.article-content a {
  color: var(--md-primary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  word-break: break-word;
  overflow-wrap: anywhere;
}

.article-content img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 20px 0;
  border-radius: var(--md-shape-md);
}

.article-content code {
  background-color: var(--md-surface-container-high);
  border: none;
  border-radius: var(--md-shape-xs);
  padding: 2px 6px;
  font-family: var(--md-font-mono);
  font-size: 0.875em;
  color: var(--md-on-surface);
  word-break: break-word;
  overflow-wrap: anywhere;
}

.article-content pre {
  background-color: var(--md-surface-container-high);
  border: none;
  border-radius: var(--md-shape-md);
  padding: 20px;
  margin: 20px 0;
  overflow-x: auto;
  white-space: pre-wrap;
  word-wrap: break-word;
}

.article-content pre code {
  background: none;
  padding: 0;
  display: block;
  white-space: pre-wrap;
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 0.9375rem;
}

.article-content th,
.article-content td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--md-outline-variant);
  text-align: left;
}

.article-content th {
  font-weight: 500;
  color: var(--md-on-surface-variant);
  background-color: var(--md-surface-container-low);
}

/* ==========================================================================
   Text fields (Material filled text field 相当)
   ========================================================================== */

.edit-form,
.md-form-surface {
  background-color: var(--md-surface-container-lowest);
  border-radius: var(--md-shape-lg);
  box-shadow: var(--md-elevation-1);
  padding: 28px 32px;
  margin: 20px 0 32px;
}

.form-group {
  margin-bottom: 24px;
}

.form-group > label,
.form-label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.006em;
  color: var(--md-on-surface-variant);
}

.form-control,
select.form-control,
textarea.form-control,
input[type='text'],
input[type='password'],
input[type='email'],
select,
textarea {
  display: block;
  width: 100%;
  padding: 14px 16px;
  font-family: inherit;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--md-on-surface);
  background-color: var(--md-surface-container-highest);
  background-clip: padding-box;
  border: none;
  border-bottom: 1px solid var(--md-on-surface-variant);
  border-radius: var(--md-shape-xs) var(--md-shape-xs) 0 0;
  box-shadow: none;
  transition: border-color var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-medium) var(--md-easing-standard);
}

.form-control:hover,
input[type='text']:hover,
input[type='password']:hover,
select:hover,
textarea:hover {
  border-bottom-color: var(--md-on-surface);
}

.form-control:focus,
input[type='text']:focus,
input[type='password']:focus,
select:focus,
textarea:focus {
  outline: none;
  color: var(--md-on-surface);
  background-color: var(--md-surface-container-highest);
  border-bottom: 2px solid var(--md-primary);
  padding-bottom: 13px;
  box-shadow: none;
}

.form-control::placeholder {
  color: var(--md-on-surface-variant);
  opacity: 0.7;
}

textarea.form-control {
  border-radius: var(--md-shape-sm);
  border-bottom: 1px solid var(--md-on-surface-variant);
  resize: vertical;
  min-height: 140px;
  font-family: var(--md-font-mono);
  font-size: 0.9375rem;
  line-height: 1.7;
}

textarea.form-control:focus {
  border-bottom: 2px solid var(--md-primary);
}

select.form-control,
select {
  appearance: none;
  -webkit-appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, currentColor 50%),
    linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: calc(100% - 20px) calc(50% + 2px), calc(100% - 14px) calc(50% + 2px);
  background-size: 6px 6px, 6px 6px;
  background-repeat: no-repeat;
  padding-right: 44px;
}

/* Floating label (login) */
.form-floating {
  position: relative;
  margin-bottom: 20px;
}

.form-floating > .form-control {
  height: 56px;
  padding: 24px 16px 8px;
}

/* ラベルと placeholder の二重表示を防ぐ */
.form-floating > .form-control::placeholder {
  color: transparent;
}

.form-floating > label {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  padding: 16px;
  margin: 0;
  color: var(--md-on-surface-variant);
  pointer-events: none;
  transform-origin: 0 0;
  transition: transform var(--md-duration-medium) var(--md-easing-standard),
    color var(--md-duration-medium) var(--md-easing-standard);
}

.form-floating > .form-control:focus ~ label,
.form-floating > .form-control:not(:placeholder-shown) ~ label {
  transform: scale(0.75) translateY(-10px);
  color: var(--md-primary);
  opacity: 1;
}

/* Radio / checkbox */
.form-check {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 0;
  margin: 0 20px 0 0;
}

.form-check-inline {
  display: inline-flex;
}

.form-check-input {
  appearance: none;
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  margin: 0;
  flex: 0 0 auto;
  border: 2px solid var(--md-on-surface-variant);
  background-color: transparent;
  cursor: pointer;
  transition: border-color var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-medium) var(--md-easing-standard);
}

.form-check-input[type='radio'] {
  border-radius: 50%;
}

.form-check-input:checked {
  border-color: var(--md-primary);
  background-color: var(--md-primary);
  box-shadow: inset 0 0 0 3px var(--md-surface);
}

.form-check-input:focus {
  outline: none;
  box-shadow: 0 0 0 8px rgba(var(--md-primary-rgb), 0.12);
}

.form-check-input:checked:focus {
  box-shadow: inset 0 0 0 3px var(--md-surface), 0 0 0 8px rgba(var(--md-primary-rgb), 0.12);
}

.form-check label,
.form-check + label {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--md-on-surface);
  cursor: pointer;
}

/* ==========================================================================
   Feedback: alerts / progress
   ========================================================================== */

.alert {
  padding: 16px 20px;
  margin-bottom: 16px;
  border: none;
  border-radius: var(--md-shape-md);
  font-size: 0.875rem;
  color: var(--md-on-surface);
  background-color: var(--md-surface-container-high);
}

.alert-info {
  background-color: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
}

.alert-success {
  background-color: var(--md-primary-container);
  color: var(--md-on-primary-container);
}

.alert-danger {
  background-color: var(--md-error-container);
  color: var(--md-on-error-container);
}

.progress {
  height: 4px;
  overflow: hidden;
  border-radius: var(--md-shape-full);
  background-color: rgba(var(--md-primary-rgb), 0.24);
}

.progress-bar {
  height: 100%;
  background-color: var(--md-primary);
  border-radius: var(--md-shape-full);
  transition: width var(--md-duration-medium) var(--md-easing-standard);
}

/* ==========================================================================
   Details / expansion panel
   ========================================================================== */

details {
  background-color: var(--md-surface-container-low);
  border-radius: var(--md-shape-md);
  padding: 4px 8px;
  margin: 20px 0;
  transition: background-color var(--md-duration-long) var(--md-easing-standard);
}

details > summary {
  list-style: none;
  cursor: pointer;
  padding: 16px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--md-on-surface);
  border-radius: var(--md-shape-sm);
  display: flex;
  align-items: center;
  gap: 12px;
  transition: background-color var(--md-duration-medium) var(--md-easing-standard);
}

details > summary::-webkit-details-marker {
  display: none;
}

details > summary::before {
  content: '';
  width: 0;
  height: 0;
  border-left: 5px solid currentColor;
  border-top: 5px solid transparent;
  border-bottom: 5px solid transparent;
  transition: transform var(--md-duration-medium) var(--md-easing-standard);
}

details[open] > summary::before {
  transform: rotate(90deg);
}

details > summary:hover {
  background-color: rgba(var(--md-on-surface-rgb), 0.08);
}

details .edit-form {
  box-shadow: none;
  background-color: transparent;
  padding: 8px 16px 16px;
  margin: 0;
}

/* ==========================================================================
   Drop zone (画像アップロード)
   ========================================================================== */

.image-upload-section {
  margin-top: 8px;
}

.drop-zone {
  padding: 32px 24px;
  text-align: center;
  cursor: pointer;
  border: 2px dashed var(--md-outline-variant);
  border-radius: var(--md-shape-md);
  background-color: var(--md-surface-container-low);
  transition: border-color var(--md-duration-medium) var(--md-easing-standard),
    background-color var(--md-duration-medium) var(--md-easing-standard);
}

.drop-zone:hover {
  border-color: var(--md-primary);
  background-color: rgba(var(--md-primary-rgb), 0.05);
}

.drop-zone.dragover {
  border-color: var(--md-primary);
  background-color: rgba(var(--md-primary-rgb), 0.12);
}

.drop-zone p {
  margin: 8px 0;
  color: var(--md-on-surface-variant);
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
  flex-shrink: 0;
  margin-top: 48px;
  padding: 28px 0;
  background-color: var(--md-surface-container) !important;
  color: var(--md-on-surface-variant);
  transition: background-color var(--md-duration-long) var(--md-easing-standard);
}

.footer .container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px 20px;
}

.footer span,
.footer a {
  color: var(--md-on-surface-variant) !important;
  font-size: 0.8125rem;
  letter-spacing: 0.025em;
}

.footer a:hover {
  color: var(--md-primary) !important;
}

/* ==========================================================================
   Utilities（Bootstrap 由来のクラスを Material の余白に合わせる）
   ========================================================================== */

.md-empty-state {
  padding: 48px 24px;
  text-align: center;
  color: var(--md-on-surface-variant);
  background-color: var(--md-surface-container-low);
  border-radius: var(--md-shape-lg);
  margin: 24px 0;
}

.md-page-header {
  margin: 32px 0 8px;
}

.md-divider {
  height: 1px;
  background-color: var(--md-outline-variant);
  border: none;
  margin: 24px 0;
}

/* 認証フォームなど、幅を絞ったカード */
.md-auth-card {
  max-width: 460px;
  margin: 48px auto;
}

.md-auth-card h1 {
  margin: 0 0 24px;
}

.md-error-text {
  margin: 8px 0 16px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--md-error);
}

/* select の直後に続くラベルの間隔 */
.md-field-spacing {
  margin-top: 20px;
}

.md-radio-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  margin-top: 4px;
}

.md-supporting-text {
  margin: 8px 0 0;
}

.md-uploaded-image {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 1024px) {
  .row {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  }

  .display-3 {
    font-size: 2rem;
  }
}

@media (max-width: 768px) {
  .container,
  .container-fluid {
    padding: 0 16px;
  }

  .md-top-app-bar {
    min-height: 56px;
    gap: 4px;
  }

  .navbar-brand {
    font-size: 1.125rem;
    padding: 8px;
  }

  .md-top-app-bar .nav-link {
    padding: 10px 12px;
  }

  .row {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .card {
    min-height: 0;
    padding: 16px;
  }

  .display-3 {
    font-size: 1.75rem;
    margin: 24px 0 8px;
  }

  .article-content,
  .edit-form,
  .md-form-surface {
    padding: 20px;
    border-radius: var(--md-shape-md);
  }

  .action-buttons {
    margin: 16px 0 24px;
    gap: 8px;
  }

  .btn {
    padding: 10px 20px;
  }
}

@media (max-width: 480px) {
  .display-3 {
    font-size: 1.5rem;
  }

  .card-title {
    font-size: 1rem;
  }

  .article-content,
  .edit-form,
  .md-form-surface {
    padding: 16px;
  }

  .article-content pre {
    padding: 14px;
    font-size: 0.85em;
  }
}

/* ==========================================================================
   Accessibility
   ========================================================================== */

@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;
  }
}