/* ==========================================================================
   thumbnaildownload.in - Clean Minimalist Utility CSS
   Zero Bloat | Pure White Aesthetic | 100/100 Core Web Vitals
   ========================================================================== */

:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #6b7280;
  --border-color: #e5e7eb;
  --border-focus: #111827;
  --primary-accent: #e02424;
  --primary-hover: #c81e1e;
  --dark-btn: #111827;
  --dark-btn-hover: #1f2937;
  --success: #059669;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --max-width: 1080px;
  --content-width: 820px;
}

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

html {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-primary);
}

a {
  color: var(--text-primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--primary-accent);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.88em;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--text-primary);
  word-break: break-all;
  overflow-wrap: anywhere;
}

pre {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 0.88rem;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  max-width: 100%;
}

/* Container */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

.content-container {
  width: 100%;
  max-width: var(--content-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* Header & Navigation */
.site-header {
  border-bottom: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.brand-logo-mark {
  display: inline-flex;
  align-items: baseline;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 1.65rem;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.06em;
  color: #111827;
  background: transparent;
  border: none;
  padding: 0;
  margin-right: 2px;
  user-select: none;
}

.brand-logo-mark .mark-dot {
  display: inline-block;
  width: 5.5px;
  height: 5.5px;
  background-color: #e02424;
  margin-left: 2px;
  margin-bottom: 2px;
  border-radius: 1px;
}

.brand-highlight {
  color: var(--primary-accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--text-primary);
}

/* Hero Section */
.hero-section {
  padding: 48px 0 32px 0;
  text-align: center;
}

.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  padding: 4px 12px;
  border-radius: 9999px;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 620px;
  margin: 0 auto 32px auto;
  line-height: 1.5;
}

/* Tool Box Card */
.tool-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  max-width: 760px;
  margin: 0 auto;
}

.input-group {
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
}

.url-input-wrapper {
  position: relative;
  flex: 1;
  display: flex;
  align-items: center;
}

.url-input {
  width: 100%;
  height: 52px;
  padding: 0 46px 0 16px;
  font-size: 1rem;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  outline: none;
  transition: all 0.15s ease;
}

.url-input:focus {
  background-color: var(--bg-primary);
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(17, 24, 39, 0.08);
}

.clear-btn {
  position: absolute;
  right: 12px;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  display: none;
  padding: 4px;
}

.clear-btn:hover {
  color: var(--text-primary);
}

.btn-primary {
  height: 52px;
  padding: 0 24px;
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  background-color: var(--dark-btn);
  border: 1px solid var(--dark-btn);
  border-radius: var(--radius-md);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  white-space: nowrap;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.08);
  transition: all 0.15s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-primary:hover {
  background-color: var(--dark-btn-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.12);
}

.btn-primary:active {
  transform: translateY(0.5px);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.08);
}

.btn-secondary {
  height: 42px;
  padding: 0 16px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: all 0.15s ease;
}

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

.input-helper-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 6px 4px 0 4px;
  flex-wrap: wrap;
  gap: 10px;
}

.input-shortcuts {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.btn-paste, .btn-sample {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-secondary);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  cursor: pointer;
  padding: 5px 12px;
  border-radius: 9999px;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  transition: all 0.15s ease;
}

.btn-paste:hover, .btn-sample:hover {
  color: var(--text-primary);
  background-color: #f3f4f6;
  border-color: #cbd5e1;
  transform: translateY(-1px);
}

.btn-paste:active, .btn-sample:active {
  transform: translateY(0);
}

.input-hint {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* Status & Feedback Alerts */
.status-msg {
  display: none;
  padding: 12px 16px;
  margin-top: 16px;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  text-align: left;
}

.status-msg.error {
  display: flex;
  align-items: center;
  gap: 10px;
  background-color: #fef2f2;
  border: 1px solid #fee2e2;
  color: #991b1b;
}

.status-msg.info {
  display: flex;
  align-items: center;
  gap: 10px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
}

/* Results Display */
.results-section {
  display: none;
  margin-top: 40px;
}

.results-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.results-title {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.video-id-badge {
  font-size: 0.85rem;
  font-family: monospace;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
}

.thumbnails-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.thumb-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.thumb-card:hover {
  border-color: #cbd5e1;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
  transform: translateY(-2px);
}

.thumb-card.highlight {
  grid-column: 1 / -1;
}

.thumb-media-wrapper {
  position: relative;
  background-color: #000000;
  aspect-ratio: 16 / 9;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.thumb-media-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.res-tag {
  position: absolute;
  top: 10px;
  left: 10px;
  background-color: rgba(17, 24, 39, 0.85);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 4px;
  backdrop-filter: blur(4px);
}

.thumb-meta {
  padding: 16px;
  display: flex;
  flex-direction: column;
  flex: 1;
  justify-content: space-between;
  gap: 14px;
  background-color: var(--bg-primary);
}

.thumb-info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.thumb-label {
  font-weight: 600;
  font-size: 1rem;
  color: var(--text-primary);
}

.thumb-dims {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-family: monospace;
}

.thumb-options-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 8px 10px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
}

.format-selector-wrapper {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.82rem;
}

.format-label {
  font-weight: 600;
  color: var(--text-secondary);
}

.format-select {
  padding: 3px 8px;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  outline: none;
  cursor: pointer;
}

.format-select:focus {
  border-color: var(--border-focus);
}

.btn-open-link {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  text-decoration: none;
}

.btn-open-link:hover {
  color: var(--text-primary);
  text-decoration: underline;
}

.thumb-fallback-alert {
  padding: 8px 12px;
  font-size: 0.82rem;
  line-height: 1.4;
  color: #92400e;
  background-color: #fef3c7;
  border: 1px solid #fde68a;
  border-radius: var(--radius-sm);
}

.thumb-actions {
  display: flex;
  gap: 8px;
}

.thumb-actions .btn-download {
  flex: 2;
  height: 42px;
  font-size: 0.9rem;
  font-weight: 600;
  background-color: var(--dark-btn);
  color: #ffffff;
  border: 1px solid var(--dark-btn);
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.06);
  transition: all 0.15s ease;
}

.thumb-actions .btn-download:hover {
  background-color: var(--dark-btn-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.12);
}

.thumb-actions .btn-download:active {
  transform: translateY(0.5px);
}

.thumb-actions .btn-copy {
  flex: 1;
  height: 40px;
  font-size: 0.85rem;
  font-weight: 500;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  transition: all 0.15s ease;
}

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

/* Feature Grid */
.features-section {
  padding: 60px 0;
  border-top: 1px solid var(--border-color);
  margin-top: 60px;
}

.section-head {
  text-align: center;
  margin-bottom: 40px;
}

.section-title {
  font-size: 1.85rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-box {
  padding: 24px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-primary);
}

.feature-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.feature-heading {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.feature-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* Content & Guide Layout */
.article-content {
  padding: 48px 0;
  line-height: 1.7;
  color: var(--text-secondary);
}

.article-content h1 {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  line-height: 1.2;
}

.article-content h2 {
  font-size: 1.55rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin: 40px 0 16px 0;
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 24px 0 10px 0;
}

.article-content p {
  margin-bottom: 16px;
}

.article-content ul, 
.article-content ol {
  margin: 0 0 20px 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content strong {
  color: var(--text-primary);
}

/* Data Table */
.data-table-wrapper {
  overflow-x: auto;
  margin: 24px 0 32px 0;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.92rem;
}

.data-table th, 
.data-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-color);
}

.data-table th {
  background-color: var(--bg-secondary);
  font-weight: 600;
  color: var(--text-primary);
}

.data-table tr:last-child td {
  border-bottom: none;
}

.data-table tr:hover td {
  background-color: var(--bg-secondary);
}

/* Step-by-Step Card */
.steps-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin: 24px 0 32px 0;
}

.step-card {
  display: flex;
  gap: 16px;
  padding: 20px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-primary);
}

.step-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: var(--dark-btn);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.step-body h4 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.step-body p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  margin: 0;
}

/* FAQ Accordion */
.faq-section {
  padding: 48px 0;
  border-top: 1px solid var(--border-color);
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-width: var(--content-width);
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--bg-primary);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.02);
  transition: all 0.15s ease;
}

.faq-item:hover {
  border-color: #cbd5e1;
}

.faq-item summary {
  padding: 18px 20px 8px 20px;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text-primary);
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "▾";
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: transform 0.15s ease;
  flex-shrink: 0;
  margin-left: 8px;
}

.faq-item[open] summary::after {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 20px 18px 20px;
  color: var(--text-secondary);
  font-size: 0.94rem;
  line-height: 1.65;
  overflow-wrap: break-word;
  word-break: break-word;
}

/* Breadcrumbs */
.breadcrumb-nav {
  padding: 16px 0;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
  flex-wrap: wrap;
}

.breadcrumb-list li+li::before {
  content: "/";
  margin-right: 8px;
  color: var(--border-color);
}

.breadcrumb-list a {
  color: var(--text-secondary);
}

.breadcrumb-list a:hover {
  color: var(--text-primary);
}

/* Toast Notification */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background-color: var(--dark-btn);
  color: #ffffff;
  padding: 12px 20px;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 500;
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: all 0.2s ease;
  z-index: 100;
}

.toast.show {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

/* Site Footer */
.site-footer {
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  margin-top: auto;
  padding: 48px 0 24px 0;
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 36px;
}

.footer-brand p {
  color: var(--text-secondary);
  margin-top: 10px;
  max-width: 320px;
  font-size: 0.88rem;
  line-height: 1.5;
}

.footer-col h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 14px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: var(--text-secondary);
}

.footer-links a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.82rem;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-disclaimer-note {
  max-width: 600px;
  line-height: 1.45;
}

/* ==========================================================================
   Responsive & Mobile-First Optimization
   Designed for iPhone SE (320px-375px), standard Android/iOS (390px-430px),
   tablets (768px-860px), and landscape orientation
   ========================================================================== */

@keyframes menuSlideDown {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 860px) {
  .hero-title {
    font-size: 2.1rem;
  }
  .thumbnails-grid {
    grid-template-columns: 1fr;
  }
  .features-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 28px;
  }
}

@media (max-width: 768px) {
  /* Layout & Spacing */
  .container, 
  .content-container {
    padding-left: 16px;
    padding-right: 16px;
  }

  /* Sticky Header & Mobile Nav */
  .site-header {
    height: 60px;
  }

  .header-inner {
    height: 60px;
  }

  .brand-logo {
    font-size: 1.1rem;
    gap: 8px;
  }

  .brand-logo-mark {
    font-size: 1.55rem;
  }

  .mobile-menu-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    min-height: 44px;
    border: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
  }

  .mobile-menu-btn:active {
    background-color: var(--bg-tertiary);
  }

  .nav-links {
    display: none;
  }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 12px 16px 18px 16px;
    gap: 4px;
    box-shadow: 0 14px 28px -4px rgba(0, 0, 0, 0.1), 0 6px 12px -2px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    animation: menuSlideDown 0.16s ease-out;
  }

  .nav-links.open li {
    width: 100%;
  }

  .nav-links.open a {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    min-height: 46px;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
    -webkit-tap-highlight-color: transparent;
  }

  .nav-links.open a:active,
  .nav-links.open a:hover,
  .nav-links.open a.active {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
  }

  /* Hero & Primary Downloader Card */
  .hero-section {
    padding: 28px 0 24px 0;
  }

  .badge-tag {
    font-size: 0.76rem;
    padding: 4px 10px;
    margin-bottom: 12px;
  }

  .hero-title {
    font-size: 1.8rem;
    line-height: 1.2;
    letter-spacing: -0.025em;
    margin-bottom: 10px;
  }

  .hero-subtitle {
    font-size: 0.96rem;
    line-height: 1.5;
    margin: 0 auto 22px auto;
  }

  .tool-card {
    padding: 18px 16px;
    border-radius: var(--radius-md);
  }

  .input-group {
    flex-direction: column;
    gap: 10px;
    margin-bottom: 10px;
  }

  .url-input-wrapper {
    width: 100%;
  }

  /* Critical for iOS: input font-size MUST be >= 16px to prevent automatic zooming */
  .url-input {
    height: 50px;
    font-size: 16px;
    padding: 0 42px 0 14px;
    border-radius: var(--radius-sm);
  }

  .btn-primary {
    width: 100%;
    height: 50px;
    font-size: 1rem;
    border-radius: var(--radius-sm);
    -webkit-tap-highlight-color: transparent;
  }

  .btn-primary:active {
    transform: scale(0.985);
  }

  .input-helper-row {
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    text-align: left;
    font-size: 0.82rem;
  }

  .input-shortcuts {
    width: 100%;
    display: flex;
    gap: 8px;
  }

  .btn-paste, .btn-sample {
    flex: 1;
    height: 38px;
    min-height: 38px;
    justify-content: center;
    font-size: 0.82rem;
    padding: 0 10px;
    border-radius: 9999px;
    -webkit-tap-highlight-color: transparent;
  }

  .btn-paste:active, .btn-sample:active {
    background-color: var(--bg-tertiary);
  }

  /* Status Message */
  .status-msg {
    margin-top: 12px;
    font-size: 0.88rem;
    padding: 10px 14px;
  }

  /* Results Section & Thumb Cards */
  .results-section {
    margin-top: 28px;
    padding-top: 24px;
  }

  .results-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    margin-bottom: 16px;
  }

  .results-title {
    font-size: 1.35rem;
  }

  .thumbnails-grid {
    gap: 16px;
  }

  .thumb-card {
    border-radius: var(--radius-md);
  }

  .thumb-meta {
    padding: 14px;
    gap: 12px;
  }

  .thumb-label {
    font-size: 0.98rem;
  }

  .thumb-dims {
    font-size: 0.82rem;
  }

  .thumb-options-row {
    padding: 10px 12px;
    gap: 10px;
    flex-wrap: wrap;
    justify-content: space-between;
  }

  .format-selector-wrapper {
    gap: 8px;
    font-size: 0.85rem;
  }

  .format-select {
    padding: 5px 10px;
    font-size: 0.85rem;
    height: 34px;
    border-radius: 4px;
  }

  .btn-open-link {
    font-size: 0.85rem;
    padding: 4px 6px;
  }

  .thumb-actions {
    gap: 8px;
  }

  .thumb-actions .btn-download {
    height: 48px;
    min-height: 48px;
    font-size: 0.95rem;
    -webkit-tap-highlight-color: transparent;
  }

  .thumb-actions .btn-download:active {
    transform: scale(0.985);
  }

  .thumb-actions .btn-copy {
    height: 48px;
    min-height: 48px;
    min-width: 48px;
    -webkit-tap-highlight-color: transparent;
  }

  /* FAQs (Always Open on Mobile) */
  .faq-section {
    padding: 36px 0;
  }

  .section-head {
    margin-bottom: 24px;
  }

  .section-title {
    font-size: 1.5rem;
    line-height: 1.25;
  }

  .section-subtitle {
    font-size: 0.92rem;
  }

  .faq-list {
    gap: 10px;
  }

  .faq-item {
    border-radius: var(--radius-sm);
  }

  .faq-item summary {
    padding: 14px 16px 8px 16px;
    font-size: 0.98rem;
    line-height: 1.35;
    gap: 10px;
  }

  .faq-answer {
    padding: 0 16px 14px 16px;
    font-size: 0.91rem;
    line-height: 1.6;
  }

  /* Articles & Content Pages */
  .article-content {
    padding: 32px 0;
  }

  .article-content h1 {
    font-size: 1.7rem;
    line-height: 1.25;
    margin-bottom: 14px;
  }

  .article-content h2 {
    font-size: 1.32rem;
    margin: 32px 0 12px 0;
  }

  .article-content h3 {
    font-size: 1.1rem;
    margin: 20px 0 8px 0;
  }

  .article-content p, 
  .article-content li {
    font-size: 0.93rem;
    line-height: 1.62;
  }

  .article-content ul, 
  .article-content ol {
    margin: 0 0 18px 20px;
  }

  /* Steps Guide */
  .steps-container {
    gap: 12px;
    margin: 18px 0 24px 0;
  }

  .step-card {
    padding: 14px;
    gap: 12px;
  }

  .step-num {
    width: 28px;
    height: 28px;
    font-size: 0.85rem;
  }

  .step-body h4 {
    font-size: 0.98rem;
  }

  .step-body p {
    font-size: 0.88rem;
  }

  /* Responsive Data Table */
  .data-table-wrapper {
    margin: 18px -4px 24px -4px;
    border-radius: var(--radius-sm);
    -webkit-overflow-scrolling: touch;
  }

  .data-table th, 
  .data-table td {
    padding: 10px 12px;
    font-size: 0.85rem;
  }

  /* Features */
  .features-section {
    padding: 36px 0;
    margin-top: 36px;
  }

  .feature-box {
    padding: 18px;
  }

  /* Toast Notification on Mobile (Pinned to bottom full width) */
  .toast {
    left: 16px;
    right: 16px;
    bottom: 16px;
    transform: translateY(20px);
    text-align: center;
    border-radius: var(--radius-sm);
  }

  .toast.show {
    transform: translateY(0);
  }

  /* Footer on Mobile */
  .site-footer {
    padding: 36px 0 20px 0;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 28px;
  }

  .footer-brand {
    grid-column: span 2;
  }

  .footer-brand p {
    max-width: 100%;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding-top: 18px;
  }
}

@media (max-width: 480px) {
  .container, 
  .content-container {
    padding-left: 14px;
    padding-right: 14px;
  }

  .brand-logo {
    font-size: 1.02rem;
    gap: 6px;
  }

  .brand-logo-mark {
    font-size: 1.45rem;
  }

  .hero-title {
    font-size: 1.6rem;
  }

  .hero-subtitle {
    font-size: 0.92rem;
  }

  .tool-card {
    padding: 14px 12px;
  }

  .url-input {
    height: 48px;
    padding-right: 38px;
  }

  .btn-primary {
    height: 48px;
    font-size: 0.96rem;
  }

  .btn-paste, .btn-sample {
    font-size: 0.78rem;
    padding: 0 8px;
  }

  .thumb-options-row {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

  .format-selector-wrapper {
    justify-content: space-between;
    width: 100%;
  }

  .format-select {
    flex: 1;
    max-width: 120px;
  }

  .btn-open-link {
    justify-content: center;
    width: 100%;
    padding: 4px 0;
  }

  .faq-item summary {
    padding: 12px 14px 6px 14px;
    font-size: 0.95rem;
  }

  .faq-answer {
    padding: 0 14px 12px 14px;
    font-size: 0.88rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .footer-brand {
    grid-column: span 1;
  }
}

@media (max-width: 360px) {
  .container, 
  .content-container {
    padding-left: 10px;
    padding-right: 10px;
  }

  .hero-title {
    font-size: 1.42rem;
  }

  .brand-logo {
    font-size: 0.95rem;
  }

  .input-shortcuts {
    flex-direction: column;
  }

  .btn-paste, .btn-sample {
    width: 100%;
  }

  .thumb-actions {
    flex-direction: column;
  }

  .thumb-actions .btn-copy {
    width: 100%;
  }
}