/* ===== CSS Variables ===== */
:root {
  --bg: #0f0f14;
  --bg-card: #1a1a24;
  --bg-input: #12121a;
  --border: #2a2a3a;
  --border-active: #6c5ce7;
  --text: #e0e0e8;
  --text-dim: #8888a0;
  --accent: #6c5ce7;
  --accent-hover: #7d6ff0;
  --accent-glow: rgba(108, 92, 231, 0.3);
  --danger: #e74c3c;
  --success: #2ecc71;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 4px 24px rgba(0,0,0,.4);
  --transition: 0.2s ease;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

/* ===== App Layout ===== */
.app {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px 40px;
}

/* ===== Header ===== */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
  margin-bottom: 28px;
}
.logo {
  font-size: 1.4rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}
.logo span { background: linear-gradient(135deg, var(--accent), #a29bfe); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.btn-icon {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text);
  font-size: 1.2rem;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}
.btn-icon:hover { border-color: var(--accent); background: #22223a; }

/* ===== Main Layout ===== */
.main-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 28px;
  align-items: start;
}
.main-layout.no-sidebar { grid-template-columns: 1fr; }

/* ===== Model Selector ===== */
.model-selector {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 20px;
}
.model-option { cursor: pointer; }
.model-option input { display: none; }
.model-card {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 18px;
  background: var(--bg-card);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}
.model-option input:checked + .model-card {
  border-color: var(--accent);
  box-shadow: 0 0 16px var(--accent-glow);
  background: #1e1e32;
}
.model-card:hover { border-color: var(--border-active); }
.model-icon { font-size: 1.5rem; }
.model-name { font-weight: 600; flex: 1; }
.model-tag {
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: 20px;
  background: var(--bg);
  color: var(--text-dim);
  border: 1px solid var(--border);
}

/* ===== Prompt Area ===== */
.prompt-area { margin-bottom: 16px; }
.prompt-area textarea {
  width: 100%;
  padding: 16px;
  background: var(--bg-input);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 1rem;
  font-family: inherit;
  resize: vertical;
  transition: border-color var(--transition);
}
.prompt-area textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 12px var(--accent-glow);
}
.prompt-area textarea::placeholder { color: #555; }
.prompt-footer {
  display: flex;
  justify-content: space-between;
  padding: 6px 4px 0;
  font-size: 0.8rem;
  color: var(--text-dim);
}
.btn-text {
  background: none;
  border: none;
  color: var(--text-dim);
  cursor: pointer;
  font-size: 0.8rem;
  transition: color var(--transition);
}
.btn-text:hover { color: var(--text); }

/* ===== Image Upload ===== */
.image-upload-area { margin-bottom: 16px; }
.upload-zone {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 18px;
  background: var(--bg-input);
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--transition);
}
.upload-zone:hover {
  border-color: var(--accent);
  background: #18182a;
}
.upload-icon { font-size: 1.3rem; }
.upload-text { color: var(--text-dim); font-size: 0.9rem; }
.image-preview {
  position: relative;
  display: inline-block;
}
.image-preview img {
  max-width: 200px;
  max-height: 200px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  object-fit: contain;
  display: block;
}
.btn-remove-image {
  position: absolute;
  top: -8px;
  right: -8px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--danger);
  color: #fff;
  border: none;
  font-size: 0.8rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition);
}
.btn-remove-image:hover { background: #d63031; }

@media (max-width: 480px) {
  .upload-zone { padding: 14px; gap: 8px; }
  .upload-text { font-size: 0.82rem; }
  .image-preview img { max-width: 140px; max-height: 140px; }
}

/* ===== Params ===== */
.params {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}
.param-group { flex: 1; min-width: 100px; }
.param-group label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 4px;
}
.param-group select {
  width: 100%;
  padding: 10px 12px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.9rem;
  cursor: pointer;
  transition: border-color var(--transition);
}
.param-group select:focus { outline: none; border-color: var(--accent); }

/* ===== Generate Button ===== */
.btn-generate {
  width: 100%;
  padding: 16px;
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  border: none;
  border-radius: var(--radius);
  color: #fff;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.btn-generate:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px var(--accent-glow);
}
.btn-generate:active:not(:disabled) { transform: translateY(0); }
.btn-generate:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}
.btn-generate .btn-loading { display: none; }
.btn-generate.loading .btn-label { display: none; }
.btn-generate.loading .btn-loading { display: inline; }
.btn-generate.loading {
  background: var(--bg-card);
  border: 2px solid var(--border);
  color: var(--text-dim);
}

/* ===== Error ===== */
.error-box {
  margin-top: 16px;
  padding: 14px 18px;
  background: rgba(231, 76, 60, 0.12);
  border: 1px solid rgba(231, 76, 60, 0.3);
  border-radius: var(--radius-sm);
  color: #f88;
  font-size: 0.9rem;
}
.hidden { display: none !important; }

/* ===== Templates ===== */
.templates { margin-top: 24px; }
.templates-title { font-size: 0.85rem; color: var(--text-dim); margin-bottom: 10px; }
.template-chips { display: flex; flex-wrap: wrap; gap: 8px; }
.template-chip {
  padding: 6px 14px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 20px;
  color: var(--text-dim);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition);
  max-width: 320px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.template-chip:hover {
  border-color: var(--accent);
  color: var(--text);
  background: #1e1e32;
}

/* ===== Result Area ===== */
.result-area { margin-top: 28px; }
.result-area h2 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-dim);
}
.result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}
.result-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
  cursor: pointer;
  animation: fadeIn 0.4s ease;
}
.result-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.result-card img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
  display: block;
}
.result-card-footer {
  display: flex;
  gap: 8px;
  padding: 10px 12px;
}
.result-card-footer button {
  flex: 1;
  padding: 6px 0;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.8rem;
  cursor: pointer;
  transition: all var(--transition);
}
.result-card-footer button:hover {
  border-color: var(--accent);
  background: #1e1e32;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ===== Loading Spinner ===== */
.loading-grid {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 0;
  gap: 16px;
}
.loading-text {
  color: var(--text-dim);
  font-size: 0.9rem;
}
.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border);
  border-top: 4px solid var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ===== History Sidebar ===== */
.history-sidebar {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  max-height: calc(100vh - 140px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.history-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}
.history-header h3 { font-size: 1rem; }
.history-header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}
.btn-close-history {
  display: none; /* PC 隐藏 */
  width: 28px;
  height: 28px;
  padding: 0;
  font-size: 0.9rem;
  line-height: 28px;
  text-align: center;
}
.history-list {
  overflow-y: auto;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.history-item {
  display: flex;
  gap: 10px;
  align-items: center;
  padding: 8px;
  background: var(--bg);
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}
.history-item:hover { border-color: var(--accent); }
.history-item img {
  width: 56px;
  height: 56px;
  object-fit: cover;
  border-radius: 4px;
  flex-shrink: 0;
}
.history-item-info {
  flex: 1;
  min-width: 0;
}
.history-item-prompt {
  font-size: 0.78rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text);
}
.history-item-meta {
  font-size: 0.68rem;
  color: var(--text-dim);
  margin-top: 2px;
}
.history-empty {
  text-align: center;
  color: var(--text-dim);
  font-size: 0.85rem;
  padding: 40px 0;
}
.btn-history-del {
  background: none;
  border: none;
  color: var(--text-dim);
  font-size: 1.1rem;
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  line-height: 1;
  transition: all var(--transition);
  flex-shrink: 0;
  opacity: 0;
}
.history-item:hover .btn-history-del { opacity: 1; }
.btn-history-del:hover {
  color: var(--danger);
  background: rgba(231, 76, 60, 0.12);
}

/* ===== Lightbox ===== */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
}
.lightbox-bg {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.85);
  backdrop-filter: blur(4px);
}
.lightbox-content {
  position: relative;
  max-width: 90vw;
  max-height: 90vh;
  z-index: 1;
}
.lightbox-content img {
  max-width: 90vw;
  max-height: 80vh;
  object-fit: contain;
  border-radius: var(--radius);
}
.lightbox-close {
  position: absolute;
  top: -40px;
  right: 0;
  background: none;
  border: none;
  color: #fff;
  font-size: 1.6rem;
  cursor: pointer;
  opacity: 0.7;
  transition: opacity var(--transition);
}
.lightbox-close:hover { opacity: 1; }
.lightbox-actions {
  display: flex;
  justify-content: center;
  margin-top: 16px;
}
.btn-download {
  padding: 10px 28px;
  background: var(--accent);
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-size: 1rem;
  cursor: pointer;
  transition: background var(--transition);
}
.btn-download:hover { background: var(--accent-hover); }

/* ===== Confirm Dialog ===== */
.confirm-dialog {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
}
.confirm-bg {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.6);
}
.confirm-box {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 28px 20px;
  max-width: 380px;
  width: 90vw;
  animation: fadeIn 0.2s ease;
}
.confirm-msg {
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 20px;
  color: var(--text);
}
.confirm-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
}
.btn-confirm-cancel,
.btn-confirm-ok {
  padding: 8px 20px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
}
.btn-confirm-cancel {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text-dim);
}
.btn-confirm-cancel:hover { border-color: var(--text-dim); color: var(--text); }
.btn-confirm-ok {
  background: var(--danger);
  color: #fff;
}
.btn-confirm-ok:hover { background: #d63031; }

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

/* Tablet / 中等屏幕 */
@media (max-width: 900px) {
  .main-layout {
    grid-template-columns: 1fr;
  }
  .app {
    padding: 0 16px 32px;
  }
  .result-grid {
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 12px;
  }
}

/* 手机横屏 / 小平板 */
@media (max-width: 800px) {
  .header {
    padding: 14px 0;
    margin-bottom: 20px;
  }
  .logo { font-size: 1.2rem; }
  .model-selector { gap: 8px; }
  .model-card {
    padding: 10px 12px;
    gap: 6px;
  }
  .model-icon { font-size: 1.2rem; }
  .model-name { font-size: 0.9rem; }

  /* -- 移动端侧栏 -- */
  .history-sidebar {
    position: fixed;
    right: 0;
    top: 0;
    width: min(320px, 85vw);
    height: 100vh;
    height: 100dvh;
    max-height: none;
    z-index: 100;
    border-radius: 0;
    border: none;
    padding: 16px;
    transform: translateX(100%);
    transition: transform 0.3s cubic-bezier(.4,0,.2,1);
    box-shadow: -8px 0 40px rgba(0,0,0,.6);
  }
  .history-sidebar.show { transform: translateX(0); }
  .btn-close-history {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    font-size: 1rem;
  }
  .history-header { margin-bottom: 14px; }
  .history-header h3 { font-size: 0.95rem; }
  .history-list { gap: 8px; }
  .history-item {
    padding: 10px;
    gap: 10px;
  }
  .history-item img {
    width: 48px;
    height: 48px;
    border-radius: 6px;
  }
  .history-item-prompt { font-size: 0.8rem; }
  .history-item-meta { font-size: 0.7rem; }
  .btn-history-del {
    opacity: 1;
    width: 28px;
    height: 28px;
    padding: 0;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
  }

  .params { gap: 8px; }
  .result-grid {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 10px;
  }
  .result-card:hover { transform: none; }
  .result-card-footer {
    gap: 4px;
    padding: 8px 10px;
  }
  .result-card-footer button {
    font-size: 0.72rem;
    padding: 6px 4px;
  }

  .lightbox-content { max-width: 95vw; }
  .lightbox-content img { max-width: 95vw; max-height: 70vh; }
  .lightbox-close { top: -36px; right: 0; font-size: 1.4rem; }
  .btn-download { padding: 10px 24px; font-size: 0.9rem; }
}

/* 手机竖屏 */
@media (max-width: 480px) {
  .app {
    padding: 0 10px 24px;
  }
  .header {
    padding: 12px 0;
    margin-bottom: 16px;
  }
  .logo { font-size: 1rem; gap: 4px; }
  .btn-icon { padding: 6px 10px; font-size: 1rem; }

  .model-selector {
    grid-template-columns: 1fr 1fr;
    gap: 6px;
  }
  .model-card {
    padding: 8px 10px;
    gap: 4px;
  }
  .model-name { font-size: 0.82rem; }
  .model-tag { font-size: 0.62rem; padding: 1px 6px; }

  .prompt-area textarea {
    padding: 12px;
    font-size: 16px; /* 防止 iOS 缩放 */
    border-radius: var(--radius-sm);
  }
  .prompt-footer { font-size: 0.72rem; }

  .params {
    flex-direction: column;
    gap: 6px;
  }
  .param-group select {
    padding: 8px 10px;
    font-size: 0.85rem;
  }

  .btn-generate { padding: 14px; font-size: 1rem; }

  .template-chip {
    font-size: 0.78rem;
    padding: 5px 10px;
    max-width: 260px;
  }

  .result-area { margin-top: 20px; }
  .result-area h2 { font-size: 1rem; margin-bottom: 10px; }
  .result-grid {
    grid-template-columns: 1fr 1fr;
    gap: 8px;
  }
  .result-card-footer {
    flex-direction: column;
    gap: 4px;
    padding: 6px 8px;
  }
  .result-card-footer button {
    font-size: 0.7rem;
    padding: 5px 0;
  }

  .history-sidebar {
    width: 100vw;
    padding: 14px;
  }
  .history-header { margin-bottom: 12px; }
  .history-header h3 { font-size: 0.9rem; }
  .btn-close-history { width: 36px; height: 36px; font-size: 1.1rem; }
  .history-item {
    padding: 12px 10px;
    gap: 12px;
  }
  .history-item img {
    width: 52px;
    height: 52px;
  }
  .history-item-prompt { font-size: 0.82rem; }
  .btn-history-del {
    width: 32px;
    height: 32px;
    font-size: 1.3rem;
  }

  .lightbox-close { top: -30px; font-size: 1.2rem; }
  .lightbox-actions { margin-top: 10px; }
  .btn-download { padding: 8px 20px; font-size: 0.85rem; }

  .spinner { width: 36px; height: 36px; }
  .loading-text { font-size: 0.8rem; }
}

/* 小屏手机 */
@media (max-width: 360px) {
  .model-selector {
    grid-template-columns: 1fr;
  }
  .result-grid {
    grid-template-columns: 1fr;
  }
}