/* ============================================================
   全局样式 + 暗色模式（CSS 变量）
   ============================================================ */

/* ---------- 设计令牌 ---------- */
:root {
  --bg: #ffffff;
  --bg-soft: #f9fafb;
  --bg-card: #ffffff;
  --fg: #1a1a1a;
  --fg-soft: #6b7280;
  --border: #e5e7eb;
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --primary-fg: #ffffff;
  --danger: #ef4444;
  --success: #22c55e;
  --warning: #f59e0b;
  --code-bg: #f3f4f6;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.08);
  --radius: 8px;
  --radius-sm: 4px;
  --container: 1100px;
  --header-h: 60px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

html.dark {
  --bg: #1a1a1a;
  --bg-soft: #242424;
  --bg-card: #242424;
  --fg: #e5e7eb;
  --fg-soft: #9ca3af;
  --border: #374151;
  --primary: #60a5fa;
  --primary-hover: #3b82f6;
  --primary-fg: #1a1a1a;
  --code-bg: #2d2d2d;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.3), 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.4);
}

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

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

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.2s ease, color 0.2s ease;
}

a {
  color: var(--primary);
  text-decoration: none;
}
a:hover {
  color: var(--primary-hover);
}

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

textarea,
input,
select {
  font-family: inherit;
  font-size: inherit;
}

/* ---------- 布局容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 20px;
}

.main {
  flex: 1;
  padding: 32px 0;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  backdrop-filter: saturate(180%) blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--fg);
}
.logo-icon {
  font-size: 1.3rem;
}

.site-nav {
  display: flex;
  gap: 24px;
}
.nav-link {
  color: var(--fg-soft);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 6px 0;
  border-bottom: 2px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}
.nav-link:hover {
  color: var(--fg);
  border-bottom-color: var(--primary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  color: var(--fg-soft);
  transition: background-color 0.15s, color 0.15s;
}
.icon-btn:hover {
  background: var(--bg-soft);
  color: var(--fg);
}

/* 主题图标切换 */
.icon-moon {
  display: none;
}
html.dark .icon-sun {
  display: none;
}
html.dark .icon-moon {
  display: block;
}

/* 语言切换 */
.lang-switch {
  position: relative;
}
.lang-switch summary {
  list-style: none;
}
.lang-switch summary::-webkit-details-marker {
  display: none;
}
.lang-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 4px);
  min-width: 140px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lg);
  padding: 4px;
  z-index: 50;
}
.lang-item {
  display: block;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: var(--fg);
  font-size: 0.9rem;
}
.lang-item:hover {
  background: var(--bg-soft);
}
.lang-item.active {
  color: var(--primary);
  font-weight: 600;
}

.menu-btn {
  display: none;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  background: var(--bg-soft);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--fg-soft);
}

/* ---------- 首页 Hero ---------- */
.hero {
  text-align: center;
  padding: 48px 0 32px;
}
.hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--primary), #8b5cf6);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero p {
  margin-top: 12px;
  font-size: 1.1rem;
  color: var(--fg-soft);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.hero-actions {
  margin-top: 24px;
  display: flex;
  gap: 12px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 0.95rem;
  transition: background-color 0.15s, color 0.15s, transform 0.1s;
}
.btn:active {
  transform: translateY(1px);
}
.btn-primary {
  background: var(--primary);
  color: var(--primary-fg);
}
.btn-primary:hover {
  background: var(--primary-hover);
  color: var(--primary-fg);
}
.btn-outline {
  border: 1px solid var(--border);
  color: var(--fg);
}
.btn-outline:hover {
  background: var(--bg-soft);
}

/* ---------- 工具网格 ---------- */
.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}

.tool-card {
  display: block;
  padding: 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
  color: var(--fg);
}
.tool-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
  color: var(--fg);
}
.tool-card-icon {
  font-size: 1.5rem;
  margin-bottom: 8px;
}
.tool-card-name {
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 4px;
}
.tool-card-desc {
  font-size: 0.875rem;
  color: var(--fg-soft);
}

.category-label {
  display: inline-block;
  font-size: 0.75rem;
  color: var(--fg-soft);
  margin: 24px 0 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

/* ---------- 工具页通用 ---------- */
.tool-page {
  max-width: 900px;
  margin: 0 auto;
}
.tool-header {
  margin-bottom: 24px;
}
.tool-header h1 {
  font-size: 1.8rem;
  font-weight: 700;
}
.tool-header p {
  color: var(--fg-soft);
  margin-top: 4px;
}

.tool-toolbar {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.tool-btn {
  padding: 8px 16px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--fg);
  font-size: 0.9rem;
  font-weight: 500;
  transition: background-color 0.15s, border-color 0.15s;
}
.tool-btn:hover {
  background: var(--primary);
  color: var(--primary-fg);
  border-color: var(--primary);
}

.tool-textarea {
  width: 100%;
  min-height: 240px;
  padding: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  resize: vertical;
}
.tool-textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.tool-status {
  margin-top: 12px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  display: none;
}
.tool-status.show {
  display: block;
}
.tool-status.valid {
  background: rgba(34, 197, 94, 0.1);
  color: var(--success);
}
.tool-status.invalid {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.field-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--fg-soft);
  margin-bottom: 6px;
}

.tool-field {
  margin-bottom: 16px;
}

/* ---------- 广告位 ---------- */
.ad-slot {
  margin: 32px 0;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.ad-placeholder {
  width: 100%;
  min-height: 90px;
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--fg-soft);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

/* ---------- 关于页 ---------- */
.prose {
  max-width: 720px;
  margin: 0 auto;
}
.prose h1 {
  font-size: 1.8rem;
  margin-bottom: 16px;
}
.prose h2 {
  font-size: 1.3rem;
  margin: 24px 0 12px;
}
.prose p {
  color: var(--fg-soft);
  margin-bottom: 12px;
}
.prose ul {
  margin: 12px 0 12px 20px;
}
.prose li {
  color: var(--fg-soft);
  margin-bottom: 6px;
}

/* ---------- 响应式 ---------- */

/* ---------- 时间戳转换工具 ---------- */
.ts-now-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 24px;
}
.ts-now-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}
.ts-now-value {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--primary);
  background: var(--bg-soft);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
}
.ts-now-ms {
  font-size: 0.95rem;
  color: var(--fg);
}
.ts-unit {
  font-size: 0.8rem;
  color: var(--fg-soft);
}

.ts-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 16px;
}
.ts-input-row {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}
.ts-input {
  flex: 1;
  min-width: 200px;
  padding: 8px 12px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: 0.9rem;
}
.ts-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}
.ts-select {
  padding: 8px 12px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--fg);
  font-size: 0.9rem;
  cursor: pointer;
}
.ts-date-input {
  flex: 1;
}
.ts-results {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.ts-result-row {
  display: flex;
  align-items: center;
  gap: 12px;
}
.ts-result-label {
  min-width: 90px;
  font-size: 0.8rem;
  color: var(--fg-soft);
  font-weight: 500;
}
.ts-result-value {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--fg);
  background: var(--bg-soft);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  flex: 1;
  word-break: break-all;
}

/* ---------- Base64 工具交换按钮 ---------- */
.tool-btn-swap {
  margin-left: auto;
}

/* ---------- iOS 图标生成器（PC 默认两栏） ---------- */
.ios-icon-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 32px;
  align-items: start;
}

.ios-icon-preview-col {
  position: sticky;
  top: calc(var(--header-h) + 20px);
}

.ios-icon-preview {
  width: 256px;
  height: 256px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}
.ios-icon-preview::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(45deg, var(--border) 25%, transparent 25%),
    linear-gradient(-45deg, var(--border) 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, var(--border) 75%),
    linear-gradient(-45deg, transparent 75%, var(--border) 75%);
  background-size: 16px 16px;
  background-position: 0 0, 0 8px, 8px -8px, -8px 0;
  opacity: 0.3;
  z-index: 0;
}
.ios-icon-preview-img {
  position: relative;
  z-index: 1;
  border-radius: 22%;
  max-width: 100%;
  max-height: 100%;
}
.ios-icon-preview-placeholder {
  position: relative;
  z-index: 1;
  color: var(--fg-soft);
  font-size: 0.85rem;
  text-align: center;
  padding: 16px;
}

.ios-icon-preview-sizes {
  display: flex;
  gap: 12px;
  margin-top: 12px;
  flex-wrap: wrap;
}
.preview-size-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}
.preview-size-item canvas {
  border-radius: 4px;
  border: 1px solid var(--border);
  image-rendering: -webkit-optimize-contrast;
}
.preview-size-item span {
  font-size: 0.7rem;
  color: var(--fg-soft);
}

.ios-icon-controls {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.upload-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 32px 20px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s, background-color 0.15s;
}
.upload-zone:hover,
.upload-zone.dragover {
  border-color: var(--primary);
  background: var(--bg-soft);
}
.upload-icon {
  font-size: 2rem;
  margin-bottom: 8px;
}
.upload-text {
  font-weight: 500;
  margin-bottom: 4px;
}
.upload-hint {
  font-size: 0.8rem;
  color: var(--fg-soft);
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.control-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--fg-soft);
}
.control-value {
  color: var(--primary);
  font-weight: 600;
}
.control-row {
  display: flex;
  align-items: center;
  gap: 12px;
}
.color-input {
  width: 40px;
  height: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  padding: 2px;
  background: var(--bg-card);
}
.range-input {
  width: 100%;
  accent-color: var(--primary);
}
.checkbox-group {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.875rem;
  cursor: pointer;
}
.checkbox-label input[type="checkbox"] {
  accent-color: var(--primary);
}
.btn-block {
  width: 100%;
  justify-content: center;
  padding: 12px 20px;
  font-size: 1rem;
}

@media (max-width: 768px) {
  .site-nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 12px 20px;
    gap: 0;
  }
  .site-nav.open {
    display: flex;
  }
  .nav-link {
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
  }
  .nav-link:last-child {
    border-bottom: none;
  }
  .menu-btn {
    display: inline-flex;
  }
  .hero h1 {
    font-size: 1.8rem;
  }
  .hero p {
    font-size: 1rem;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 768px) {

.ios-icon-layout {
  grid-template-columns: 1fr;
  gap: 20px;
}
.ios-icon-preview-col {
  position: static;
  display: flex;
  flex-direction: column;
  align-items: center;
}
}

/* ---------- 按钮变体（抠图工具等复用） ---------- */
.btn-secondary {
  background: var(--bg-soft);
  color: var(--fg);
  border: 1px solid var(--border);
}
.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}
.btn-ghost {
  background: transparent;
  color: var(--fg-soft);
  border: 1px solid transparent;
}
.btn-ghost:hover {
  background: var(--bg-soft);
  color: var(--fg);
}
.btn-sm {
  padding: 6px 12px;
  font-size: 0.85rem;
}

/* ---------- 图片抠图工具 ---------- */
.ibr-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 24px;
  align-items: start;
}
.ibr-preview-col {
  min-width: 0;
}
.ibr-controls {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.ibr-compare {
  position: relative;
  width: 100%;
  border-radius: var(--radius);
  overflow: hidden;
  background:
    repeating-conic-gradient(var(--bg-soft) 0% 25%, transparent 0% 50%) 50% / 24px 24px;
  border: 1px solid var(--border);
  user-select: none;
}
/* 尺寸参考层：正常文档流，由图片真实比例撑开容器高度 */
.ibr-compare-sizer {
  display: block;
  width: 100%;
  height: auto;
  visibility: hidden; /* 只占位不渲染，避免透出原图覆盖透明效果 */
}
.ibr-compare-img {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.ibr-compare-img img {
  max-width: 100%;
  max-height: 100%;
  display: block;
}
.ibr-compare-after {
  z-index: 1;
}
.ibr-compare-before {
  z-index: 2;
}
.ibr-placeholder {
  color: var(--fg-soft);
  font-size: 0.95rem;
  padding: 20px;
  text-align: center;
}
.ibr-compare-divider {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--primary);
  z-index: 3;
  transform: translateX(-1px);
  box-shadow: 0 0 0 1px rgba(0,0,0,0.15);
}
.ibr-compare-range {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  opacity: 0;
  cursor: ew-resize;
  z-index: 4;
}
.ibr-compare-hint {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0,0,0,0.55);
  color: #fff;
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: 999px;
  z-index: 5;
  pointer-events: none;
}
.ibr-bg-options {
  margin-top: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.ibr-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 4px;
}

@media (max-width: 768px) {
  .ibr-layout {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}