/* ============================================================
   JINER Blog — 在线工具（索引 + 详情页）
   范围：.tools-wrap（/tools）、.tool-wrap（工具子页）
   ============================================================ */

/* ---------- /tools 索引 ---------- */
.tools-wrap {
  max-width: 720px;
  margin: 0 auto;
  padding: calc(var(--nav-height, 60px) + 1rem) 1rem 4rem;
  color-scheme: light;
}
[data-theme="dark"] .tools-wrap { color-scheme: dark; }

.tools-hero {
  text-align: center;
  padding: 4rem 0 3rem;
}
.tools-hero h1 {
  font-size: clamp(2rem, 5vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0;
}
.tools-hero h1::after {
  content: "";
  display: block;
  width: 56px;
  height: 3px;
  margin: 1rem auto 0;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--color-accent), #8b5cf6);
}
.tools-hero .sub {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 500px;
  margin: 1.25rem auto 0;
  line-height: 1.8;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr));
  gap: 1.25rem;
  margin-top: 1.5rem;
}
.tool-card {
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.5rem 1.25rem;
  text-decoration: none;
  color: inherit;
  transition: all .3s cubic-bezier(.16, 1, .3, 1);
}
.tool-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(99, 102, 241, .1);
  border-color: rgba(99, 102, 241, .25);
}
.tool-card:active { transform: translateY(0) scale(.99); }
.tool-card .icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: var(--color-accent-soft);
  font-size: 1.75rem;
  line-height: 1;
  margin-bottom: 1rem;
}
.tool-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--color-accent);
}
.tool-card p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
  flex: 1;
}
[data-theme="dark"] .tools-wrap .tool-card:hover {
  box-shadow: 0 18px 44px rgba(0, 0, 0, .5);
  border-color: rgba(167, 139, 250, .35);
}

/* ---------- 工具子页 ---------- */
.tool-wrap {
  max-width: 900px;
  margin: 0 auto;
  padding: calc(var(--nav-height, 60px) + 2.5rem) 1rem 4rem;
  color-scheme: light;
}
[data-theme="dark"] .tool-wrap { color-scheme: dark; }

.tool-hero { padding: 1rem 0 2rem; }
.tool-hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: .75rem;
}
.tool-hero p {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  line-height: 1.8;
  max-width: 620px;
}
.tool-back {
  display: inline-block;
  margin-bottom: 1rem;
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color .2s ease;
}
.tool-back:hover { color: var(--color-accent); }

.tool-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
}

/* 页签 */
.tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 1.25rem;
  border-bottom: 1px solid var(--color-border-light);
}
.tab {
  padding: 8px 16px;
  border: none;
  background: transparent;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  transition: color .2s ease, border-color .2s ease;
}
.tab:hover { color: var(--color-accent); }
.tab.active {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* 表单 */
.field { margin-bottom: 1.25rem; }
.field label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: .4rem;
}
.code-area {
  width: 100%;
  padding: .75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  line-height: 1.7;
  resize: vertical;
  transition: border-color .2s ease, box-shadow .2s ease;
}
.code-area:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}
.code-area::placeholder { color: var(--color-text-muted); opacity: 1; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .4rem;
  padding: .55rem 1.1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
  cursor: pointer;
  transition: transform .2s var(--ease), box-shadow .2s var(--ease),
              border-color .2s ease, background-color .2s ease, color .2s ease;
}
.btn:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
  transform: translateY(-1px);
}
.btn:active { transform: translateY(0); }
.btn.primary {
  background: linear-gradient(135deg, #7c3aed, #6d28d9);
  border-color: transparent;
  color: #fff;
  box-shadow: 0 4px 14px rgba(109, 40, 217, .25);
}
.btn.primary:hover {
  color: #fff;
  filter: brightness(1.06);
  box-shadow: 0 8px 20px rgba(109, 40, 217, .32);
}
[data-theme="dark"] .tool-wrap .btn.primary {
  background: #6d61a6;
  border-color: #6d61a6;
  color: #fff;
}
[data-theme="dark"] .tool-wrap .btn.primary:hover { background: #7a6fb2; }

.btn-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .6rem;
  margin-bottom: 1.25rem;
}
.hint {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
.file-btn {
  display: inline-flex;
  align-items: center;
  padding: .55rem 1rem;
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: color .2s ease, border-color .2s ease;
}
.file-btn:hover { color: var(--color-accent); border-color: var(--color-accent); }

.tool-note {
  margin-top: 1.5rem;
  padding: .9rem 1.1rem;
  border-left: 3px solid var(--color-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--color-accent-soft);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: 1.8;
}
.tool-note code {
  font-family: var(--font-mono);
  font-size: .9em;
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--color-surface);
  color: var(--color-accent);
}

/* ---------- 视频转 PNG ---------- */
.drop-zone {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: .35rem;
  padding: 2.5rem 1.5rem;
  margin-bottom: 1.5rem;
  border: 2px dashed color-mix(in srgb, var(--color-accent) 45%, transparent);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
  text-align: center;
  cursor: pointer;
  transition: border-color .2s ease, background-color .2s ease;
}
[data-theme="dark"] .drop-zone {
  border-color: color-mix(in srgb, var(--color-accent) 70%, transparent);
}
.drop-zone:hover,
.drop-zone.dragover {
  border-color: var(--color-accent);
  background: var(--color-accent-soft);
}
.drop-zone:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.drop-zone .drop-icon { font-size: 2rem; line-height: 1.2; }
.drop-zone h3 {
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-text);
  max-width: 100%;
  word-break: break-all;
}
.drop-zone p { font-size: var(--text-xs); color: var(--color-text-muted); }
.drop-zone.has-video .formats { display: none; }

.video-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  margin-bottom: 1.25rem;
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}
.video-controls input[type="number"] {
  width: 80px;
  padding: .4rem .6rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
  color: var(--color-text);
  font-family: var(--font-mono);
  color-scheme: light;
}
[data-theme="dark"] .video-controls input[type="number"] { color-scheme: dark; }

.video-stage {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: #000;
  margin-bottom: 1.25rem;
}
.video-stage video {
  display: block;
  width: 100%;
  max-height: 460px;
  background: #000;
}

.frames {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: .75rem;
  margin-bottom: 1.25rem;
}
.frame-item {
  position: relative;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: var(--color-surface-alt);
}
.frame-item img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: #000;
}
.frame-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 6px;
  padding: 6px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-muted);
}
.frame-meta a,
.frame-meta button {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 6px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text-secondary);
  text-decoration: none;
  cursor: pointer;
}
.frame-meta a:hover,
.frame-meta button:hover { color: var(--color-accent); border-color: var(--color-accent); }

/* ---------- OS 刷题 ---------- */
.quiz-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
}
.quiz-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: .9rem;
  margin-bottom: 1.25rem;
  border-bottom: 1px solid var(--color-border-light);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}
.quiz-q {
  font-size: var(--text-lg);
  font-weight: 500;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 1.25rem;
}
.quiz-tag {
  display: inline-block;
  margin-right: .5rem;
  padding: 2px 9px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 500;
  color: var(--color-accent);
  background: var(--color-accent-soft);
  vertical-align: 2px;
}
.quiz-options { display: grid; gap: .6rem; }
.quiz-option {
  display: flex;
  align-items: flex-start;
  gap: .65rem;
  padding: .8rem 1rem;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  line-height: 1.7;
  text-align: left;
  cursor: pointer;
  transition: border-color .2s ease, background-color .2s ease, color .2s ease;
}
.quiz-option:hover { border-color: var(--color-accent); color: var(--color-text); }
.quiz-option .key {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-muted);
  padding-top: 1px;
}
.quiz-option.correct {
  border-color: #16a34a;
  background: rgba(22, 163, 74, .08);
  color: #15803d;
}
.quiz-option.wrong {
  border-color: #dc2626;
  background: rgba(220, 38, 38, .07);
  color: #b91c1c;
}
[data-theme="dark"] .quiz-option.correct { color: #4ade80; }
[data-theme="dark"] .quiz-option.wrong { color: #f87171; }
.quiz-explain {
  margin-top: 1rem;
  padding: .85rem 1rem;
  border-radius: var(--radius-sm);
  background: var(--color-surface-alt);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: 1.8;
}
.quiz-footer {
  display: flex;
  justify-content: flex-end;
  gap: .6rem;
  margin-top: 1.25rem;
}
.quiz-loading { color: var(--color-text-muted); font-size: var(--text-sm); }

@media (max-width: 640px) {
  .tool-panel, .quiz-panel { padding: 1.15rem; border-radius: var(--radius-md); }
  .tools-hero { padding: 3rem 0 2rem; }
  .tool-hero h1 { font-size: 1.6rem; }
  .btn-row .hint { width: 100%; text-align: center; }
}

@media (prefers-reduced-motion: reduce) {
  .tool-card, .btn { transition: none; }
}