*,
*::before,
*::after {
  box-sizing: border-box;
}

:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --border: #dddfe4;
  --text: #111111;
  --text-muted: #5b5b63;
  --accent: #111111;
  --accent-soft: #f0f0f2;
  --error: #c0392b;
  --radius: 8px;
  --shadow-soft: 0 8px 20px rgba(0, 0, 0, 0.05);
  --transition-fast: 0.16s ease-out;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

/* Layout & header */

.container {
  width: 100%;
  max-width: 980px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 1.1rem;
  padding: 0.75rem 0;
}

.brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: inherit;
}

.brand-logo {
  width: 100px;
  height: 100px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #ffffff;
  object-fit: contain;
}

.site-nav {
  display: flex;
  align-items: center;
  flex-wrap: nowrap;
  gap: 0.4rem;
  margin-left: auto;
  white-space: nowrap;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.4rem;
  margin-left: auto;
  padding: 0.45rem 0.7rem;
  font-size: 0.95rem;
  border-radius: 10px;
  border: 1px solid #c8c8c8;
  background: #ffffff;
  cursor: pointer;
  transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  border-color: #a7a7a7;
  background: #f5f5f5;
  outline: none;
}

.nav-toggle-icon,
.nav-toggle-icon::before,
.nav-toggle-icon::after {
  display: block;
  width: 18px;
  height: 2px;
  background: #000000;
  border-radius: 999px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
  content: "";
}

.nav-toggle-icon::before {
  transform: translateY(-6px);
}

.nav-toggle-icon::after {
  transform: translateY(6px);
}

.nav-toggle.is-open .nav-toggle-icon {
  background: transparent;
}

.nav-toggle.is-open .nav-toggle-icon::before {
  transform: rotate(45deg);
}

.nav-toggle.is-open .nav-toggle-icon::after {
  transform: rotate(-45deg);
}

.nav-link {
  text-decoration: none;
  font-size: 0.9rem;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  border: 1px solid #c8c8c8;
  background: #dddddd;
  color: #000000;
  transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast);
}

.nav-link:hover {
  background: #cfcfcf;
  color: #000000;
}

.nav-link-active {
  border-color: #ff0000;
  background: #ff0000;
  color: #ffffff;
  font-weight: 700;
}

.nav-link-active:hover {
  background: #ff0000;
  color: #ffffff;
}

.site-main {
  padding-bottom: 3rem;
}

.hero {
  background: #ff0000;
  color: #ffffff;
  border-bottom: 1px solid #cc0000;
  padding: 2.3rem 0 2rem;
}

.page-title {
  margin: 0 0 0.35rem;
  font-size: clamp(1.8rem, 2.3vw, 2.2rem);
}

.site-tagline {
  margin: 0 0 1.4rem;
  color: #ffecec;
}

/* Generic sections */

.tool-section {
  padding: 2.5rem 0 1.5rem;
}

.tool-section.tool-alt {
  border-top: 1px solid var(--border);
  background: #ffffff;
}

.content-section,
.faq-section {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
}

/* Hero list */

.hero-list {
  margin: 1rem 0 0;
  padding-left: 1.2rem;
  color: #ffffff;
}

/* Form & inputs */

.tool-form {
  margin-bottom: 2rem;
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.input-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.input-text {
  flex: 1 1 220px;
  padding: 0.7rem 0.9rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  font-size: 1rem;
  outline: none;
  min-width: 0;
  background: #fff;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.input-text:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent-soft);
}

.input-text.readonly {
  background: #fafafa;
}

.input-file {
  display: block;
  margin-top: 0.3rem;
}

/* Buttons */

.btn-primary,
.btn-secondary {
  border-radius: var(--radius);
  border: 1px solid transparent;
  padding: 0.7rem 1.1rem;
  font-size: 0.95rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background-color var(--transition-fast),
              border-color var(--transition-fast),
              transform var(--transition-fast),
              box-shadow var(--transition-fast);
}

.btn-primary {
  background: var(--accent);
  color: #ffffff;
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-soft);
}

.btn-secondary {
  background: #ffffff;
  color: var(--text);
  border-color: var(--border);
}

.btn-secondary:hover {
  background: var(--accent-soft);
}

/* Helper text & errors */

.helper-text {
  margin-top: 0.5rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.error-message {
  margin-top: 0.6rem;
  font-size: 0.9rem;
  color: var(--error);
  min-height: 1.1em;
}

/* Results box */

.results {
  margin-top: 2.5rem;
  padding: 1.75rem 1.5rem 2rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #ffffff;
  box-shadow: var(--shadow-soft);
}

.results-header h3 {
  margin-top: 0;
  margin-bottom: 0.4rem;
}

.video-id-display {
  margin-top: 0;
  margin-bottom: 1rem;
  font-size: 0.95rem;
  color: var(--text-muted);
}

.result-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.2rem;
  margin-bottom: 1.2rem;
}

.result-block {
  margin-bottom: 1.3rem;
}

.result-block h4 {
  margin: 0 0 0.4rem;
  font-size: 1rem;
}

.inline-row {
  display: flex;
  gap: 0.6rem;
  align-items: center;
}

/* Embed options */

.embed-tools {
  margin-top: 1.8rem;
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
}

.embed-intro {
  margin-top: 0.3rem;
  color: var(--text-muted);
}

.embed-options {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.5rem;
  margin: 1rem 0 1.4rem;
}

.checkbox-label {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.code-row {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.code-box {
  width: 100%;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.9rem;
  padding: 0.7rem 0.9rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #fafafa;
  resize: vertical;
}

/* Thumbnails */

.thumbnails-section {
  margin-top: 2rem;
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
}

.thumbnails-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.2rem;
  margin-top: 1.2rem;
}

.thumb-card {
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--bg-alt);
  padding: 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.thumb-label-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.5rem;
}

.thumb-title {
  font-size: 0.95rem;
  font-weight: 600;
}

.thumb-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.thumb-image-wrapper {
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #ffffff;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.35rem;
}

.thumb-image-wrapper img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.thumb-actions {
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.thumb-url {
  flex: 1 1 100%;
  font-size: 0.8rem;
  color: var(--text-muted);
  word-break: break-all;
}

/* Mockup player */

.mockup-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.1fr);
  gap: 1.5rem;
  margin-top: 1.3rem;
}

.mockup-preview h3 {
  margin-top: 0;
}

.mockup-player {
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #000;
  overflow: hidden;
}

.mockup-bar {
  height: 24px;
  background: #202020;
}

.mockup-screen {
  position: relative;
  background: #000;
  padding-top: 56.25%; /* 16:9 */
}

.mockup-screen img,
.mockup-placeholder {
  position: absolute;
  inset: 0;
}

.mockup-screen img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.mockup-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  color: #888;
  font-size: 0.9rem;
  padding: 0.5rem;
}

.mockup-controls {
  height: 32px;
  background: linear-gradient(to top, rgba(0,0,0,0.5), transparent);
}

/* Channel art helper */

.channel-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.1fr);
  gap: 1.5rem;
  margin-top: 1.3rem;
}

.channel-preview-block h3 {
  margin-top: 0;
}

.channel-preview {
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #ffffff;
  padding: 0.7rem;
  position: relative;
}

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

.channel-preview .mockup-placeholder {
  position: static;
  min-height: 180px;
}

/* FAQ */

.content-section h2,
.faq-section h2 {
  margin-top: 0;
}

.faq-section details {
  margin: 0.5rem 0;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #ffffff;
  padding: 0.7rem 0.9rem;
}

.faq-section summary {
  cursor: pointer;
  font-weight: 500;
}

.faq-section p {
  margin: 0.6rem 0 0.2rem;
  font-size: 0.95rem;
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--border);
  padding: 1.2rem 0 1.6rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Responsive */

@media (max-width: 800px) {
  .header-inner {
    flex-direction: row;
    align-items: center;
    gap: 0.75rem;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    width: 100%;
    margin-left: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0.55rem;
  }

  .site-nav.is-open {
    display: flex;
  }

  .nav-link {
    width: 100%;
    text-align: center;
  }

  .mockup-grid,
  .channel-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 640px) {
  .results {
    padding: 1.3rem 1.1rem 1.6rem;
  }

  .embed-options {
    flex-direction: column;
  }
}