/* ==========================================
   そよ風掲示板 (Breeze Board) - Design System & Styles
   ========================================== */

/* Design Tokens */
:root {
  /* HSL Colors */
  --bg-primary: hsl(210, 30%, 98%);
  --bg-secondary: hsl(0, 0%, 100%);
  --bg-tertiary: hsl(210, 20%, 95%);
  
  --text-primary: hsl(220, 30%, 15%);
  --text-secondary: hsl(220, 15%, 45%);
  --text-tertiary: hsl(220, 10%, 65%);
  
  --primary: hsl(245, 80%, 60%);
  --primary-hover: hsl(245, 80%, 55%);
  --primary-light: hsl(245, 80%, 96%);
  
  --accent-zatsudan: hsl(35, 90%, 55%);
  --accent-zatsudan-light: hsl(35, 90%, 96%);
  --accent-shitsumon: hsl(215, 90%, 55%);
  --accent-shitsumon-light: hsl(215, 90%, 96%);
  --accent-gijutsu: hsl(155, 75%, 40%);
  --accent-gijutsu-light: hsl(155, 75%, 96%);
  --accent-oshirase: hsl(355, 85%, 60%);
  --accent-oshirase-light: hsl(355, 85%, 96%);

  /* Border & Shadows */
  --border-color: hsl(220, 15%, 92%);
  --border-radius-sm: 8px;
  --border-radius-md: 14px;
  --border-radius-lg: 24px;
  --border-radius-full: 9999px;
  
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.08);
  --shadow-glow: 0 10px 25px rgba(99, 102, 241, 0.25);
  
  /* Fonts */
  --font-family: 'Inter', 'Noto Sans JP', sans-serif;
  --font-display: 'Outfit', 'Noto Sans JP', sans-serif;
  
  /* Transitions */
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

/* Modern Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

/* Background Glow Effects */
.bg-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(140px);
  z-index: -1;
  opacity: 0.45;
  pointer-events: none;
  animation: float-glow 20s infinite alternate ease-in-out;
}

.bg-glow-1 {
  background: radial-gradient(circle, hsl(245, 80%, 75%) 0%, transparent 70%);
  top: -200px;
  right: -100px;
}

.bg-glow-2 {
  background: radial-gradient(circle, hsl(175, 75%, 70%) 0%, transparent 70%);
  bottom: -100px;
  left: -200px;
  animation-delay: -5s;
}

@keyframes float-glow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(40px, 30px) scale(1.1); }
}

/* Container & Layout */
.app-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 28px;
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: 24px;
  position: sticky;
  top: 16px;
  z-index: 100;
  transition: transform var(--transition-normal);
}

.header-logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  font-size: 28px;
  display: inline-block;
  animation: gentle-wave 3s infinite ease-in-out;
  transform-origin: 70% 70%;
}

.logo-text h1 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, var(--primary), hsl(210, 80%, 50%));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.2;
}

.logo-text p {
  font-size: 11px;
  color: var(--text-secondary);
  font-weight: 500;
  letter-spacing: 1px;
}

.header-search {
  flex: 0 1 400px;
  position: relative;
  margin: 0 16px;
}

.search-icon {
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 16px;
  pointer-events: none;
  opacity: 0.6;
}

#search-input {
  width: 100%;
  padding: 12px 16px 12px 44px;
  border: 1.5px solid var(--border-color);
  border-radius: var(--border-radius-full);
  background: var(--bg-secondary);
  font-family: var(--font-family);
  font-size: 14px;
  color: var(--text-primary);
  outline: none;
  transition: all var(--transition-normal);
}

#search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-light);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--border-radius-full);
  font-family: var(--font-family);
  font-size: 14px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  outline: none;
  transition: all var(--transition-normal);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), hsl(245, 75%, 55%));
  color: white;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 30px rgba(99, 102, 241, 0.35);
  filter: brightness(1.05);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--primary);
  border: 1.5px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary-light);
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

/* Main Layout Grid */
.app-main {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 28px;
  flex: 1;
}

/* Sidebar & Categories */
.app-sidebar {
  position: sticky;
  top: 110px;
  height: fit-content;
}

.sidebar-title {
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--text-tertiary);
  margin-bottom: 16px;
  padding-left: 8px;
}

.category-nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.category-pill {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  border-radius: var(--border-radius-md);
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-family: var(--font-family);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  outline: none;
  text-align: left;
  transition: all var(--transition-fast);
}

.category-pill:hover {
  background: var(--bg-secondary);
  color: var(--text-primary);
  transform: translateX(4px);
}

.category-pill.active {
  background: var(--bg-secondary);
  color: var(--primary);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

.pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: 12px;
}

.pill-label {
  flex: 1;
}

.pill-count {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-tertiary);
  background: var(--bg-tertiary);
  padding: 2px 8px;
  border-radius: var(--border-radius-full);
}

.category-pill.active .pill-count {
  background: var(--primary-light);
  color: var(--primary);
}

/* Feed Section */
.feed-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

#feed-title {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
}

.feed-sort {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-secondary);
}

.sort-dropdown {
  padding: 6px 12px;
  border-radius: var(--border-radius-sm);
  border: 1.5px solid var(--border-color);
  background: var(--bg-secondary);
  outline: none;
  font-family: var(--font-family);
  cursor: pointer;
  transition: border-color var(--transition-fast);
}

.sort-dropdown:focus {
  border-color: var(--primary);
}

/* Posts Container & Cards */
.posts-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.post-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
  animation: card-appear 0.4s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.post-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: transparent;
  transition: background var(--transition-normal);
}

.post-card[data-category-accent="雑談"]::before { background: var(--accent-zatsudan); }
.post-card[data-category-accent="質問"]::before { background: var(--accent-shitsumon); }
.post-card[data-category-accent="技術"]::before { background: var(--accent-gijutsu); }
.post-card[data-category-accent="お知らせ"]::before { background: var(--accent-oshirase); }

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary-light);
}

.post-card:active {
  transform: translateY(-1px);
}

@keyframes card-appear {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: var(--border-radius-full);
  margin-bottom: 12px;
}

.tag-zatsudan { background: var(--accent-zatsudan-light); color: var(--accent-zatsudan); }
.tag-shitsumon { background: var(--accent-shitsumon-light); color: var(--accent-shitsumon); }
.tag-gijutsu { background: var(--accent-gijutsu-light); color: var(--accent-gijutsu); }
.tag-oshirase { background: var(--accent-oshirase-light); color: var(--accent-oshirase); }

.post-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  transition: color var(--transition-fast);
}

.post-card:hover .post-title {
  color: var(--primary);
}

.post-snippet {
  font-size: 14px;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 16px;
  line-height: 1.5;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-tertiary);
  border-top: 1px solid var(--border-color);
  padding-top: 12px;
}

.author-avatar {
  background: var(--bg-tertiary);
  width: 24px;
  height: 24px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
}

.author-name {
  font-weight: 500;
  color: var(--text-secondary);
}

/* Skeleton Animations */
.skeleton {
  background: linear-gradient(90deg, #f0f0f0 25%, #f7f7f7 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s infinite;
  border-radius: 4px;
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton-card {
  pointer-events: none;
}

.skeleton-tag { width: 60px; height: 18px; margin-bottom: 12px; border-radius: 10px; }
.skeleton-title { width: 40%; height: 22px; margin-bottom: 12px; }
.skeleton-text { width: 85%; height: 16px; margin-bottom: 16px; }
.skeleton-meta { width: 150px; height: 14px; margin-top: 12px; }

/* Empty State */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 24px;
  text-align: center;
  background: var(--bg-secondary);
  border: 1.5px dashed var(--border-color);
  border-radius: var(--border-radius-md);
  margin-top: 10px;
}

.empty-icon {
  font-size: 48px;
  margin-bottom: 16px;
  animation: float-icon 4s infinite alternate ease-in-out;
}

.empty-state h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 20px;
  max-width: 320px;
}

@keyframes float-icon {
  0% { transform: translateY(0); }
  100% { transform: translateY(-8px); }
}

/* Modal Overlay & Window */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 23, 42, 0.4);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-window {
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  width: 90%;
  max-width: 550px;
  padding: 32px;
  position: relative;
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-spring);
  max-height: 90vh;
  overflow-y: auto;
}

.modal-window-large {
  max-width: 720px;
  padding: 40px;
}

.modal-overlay.active .modal-window {
  transform: scale(1) translateY(0);
}

.modal-close {
  position: absolute;
  top: 20px;
  right: 20px;
  font-size: 28px;
  background: transparent;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  outline: none;
  transition: color var(--transition-fast);
}

.modal-close:hover {
  color: var(--text-primary);
}

.modal-header {
  margin-bottom: 24px;
}

.modal-header h2 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.modal-header p {
  font-size: 13px;
  color: var(--text-secondary);
}

/* Form Styles */
.post-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group label {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
}

.required {
  color: var(--accent-oshirase);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  background: var(--bg-secondary);
  font-family: var(--font-family);
  font-size: 14px;
  color: var(--text-primary);
  outline: none;
  transition: all var(--transition-normal);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-tertiary);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--primary-light);
}

.char-counter {
  font-size: 11px;
  color: var(--text-tertiary);
  align-self: flex-end;
}

.form-actions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
  margin-top: 12px;
  border-top: 1px solid var(--border-color);
  padding-top: 20px;
}

/* Detail Modal Styles */
.detail-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 20px;
  margin-bottom: 24px;
}

#detail-title {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 8px;
  margin-bottom: 16px;
  line-height: 1.3;
}

.detail-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-secondary);
}

.detail-author-avatar {
  background: var(--bg-tertiary);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.detail-author-name {
  font-weight: 600;
  color: var(--text-primary);
}

.detail-date-text {
  color: var(--text-tertiary);
}

.detail-body {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-primary);
  white-space: pre-wrap;
  word-break: break-all;
}

/* Toast System */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 2000;
}

.toast {
  background: var(--bg-secondary);
  border-left: 4px solid var(--primary);
  box-shadow: var(--shadow-lg);
  padding: 16px 24px;
  border-radius: var(--border-radius-md);
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 280px;
  max-width: 400px;
  font-size: 13px;
  font-weight: 500;
  transform: translateY(20px);
  opacity: 0;
  animation: toast-in 0.35s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

.toast-success {
  border-left-color: var(--accent-gijutsu);
}

.toast-error {
  border-left-color: var(--accent-oshirase);
}

@keyframes toast-in {
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

/* Footer styling */
.app-footer {
  text-align: center;
  padding: 32px 0 16px;
  font-size: 12px;
  color: var(--text-tertiary);
  margin-top: auto;
}

/* Wave animation for logo icon */
@keyframes gentle-wave {
  0%, 100% { transform: rotate(0deg); }
  50% { transform: rotate(15deg); }
}

/* ==========================================
   Responsive Breakpoints
   ========================================== */
@media (max-width: 900px) {
  .app-main {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .app-sidebar {
    position: static;
  }

  .category-nav {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 6px;
  }

  .category-pill {
    padding: 8px 12px;
    font-size: 13px;
    border-radius: var(--border-radius-full);
    background: var(--bg-tertiary);
  }

  .category-pill:hover {
    transform: none;
  }
}

@media (max-width: 600px) {
  .app-container {
    padding: 12px;
  }

  .app-header {
    flex-direction: column;
    gap: 16px;
    align-items: stretch;
    padding: 16px;
    top: 8px;
    border-radius: var(--border-radius-md);
  }

  .header-search {
    margin: 0;
    order: 2;
  }

  .header-logo {
    order: 1;
    justify-content: center;
  }

  #btn-new-post {
    order: 3;
    width: 100%;
  }

  .form-grid {
    grid-template-columns: 1fr;
  }

  .modal-window {
    padding: 20px;
    width: 95%;
  }

  .modal-window-large {
    padding: 24px;
  }
  
  #detail-title {
    font-size: 20px;
  }
}