/* ==========================================================================
   YTMP3 Modern Minimalist Design System
   Font: Lexend Deca throughout
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Lexend+Deca:wght@300;400;500;600;700&display=swap');

:root {
  /* Dark Theme Tokens (Default) */
  --bg-main: #0D0F12;
  --bg-card: #171A20;
  --bg-card-hover: #1D2129;
  --bg-input: #12151B;
  --bg-surface: #1E232B;
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-input: #272C38;
  --border-focus: #1685FF;
  
  --primary-accent: #1685FF;
  --primary-hover: #0D76E8;
  --primary-glow: rgba(22, 133, 255, 0.25);
  
  --text-heading: #FFFFFF;
  --text-body: #94A3B8;
  --text-muted: #64748B;
  
  --success: #10B981;
  --error: #EF4444;
  --error-bg: rgba(239, 68, 68, 0.12);
  
  --font-family: 'Lexend Deca', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5), 0 0 1px rgba(255, 255, 255, 0.08);
  --shadow-input: inset 0 2px 4px rgba(0, 0, 0, 0.3);
  --shadow-button: 0 4px 14px 0 var(--primary-glow);
  
  --container-max: 1080px;
  --converter-max: 740px;
}

/* Light Theme Variables */
body.theme-light {
  --bg-main: #F8FAFC;
  --bg-card: #FFFFFF;
  --bg-card-hover: #F1F5F9;
  --bg-input: #F1F5F9;
  --bg-surface: #E2E8F0;
  
  --border-subtle: #E2E8F0;
  --border-input: #CBD5E1;
  --border-focus: #1685FF;
  
  --primary-accent: #1685FF;
  --primary-hover: #0D76E8;
  --primary-glow: rgba(22, 133, 255, 0.18);
  
  --text-heading: #0F172A;
  --text-body: #475569;
  --text-muted: #94A3B8;
  
  --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
  --shadow-input: inset 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-button: 0 4px 14px 0 rgba(22, 133, 255, 0.3);
}

/* System Auto Light Mode */
@media (prefers-color-scheme: light) {
  body:not(.theme-dark) {
    --bg-main: #F8FAFC;
    --bg-card: #FFFFFF;
    --bg-card-hover: #F1F5F9;
    --bg-input: #F1F5F9;
    --bg-surface: #E2E8F0;
    
    --border-subtle: #E2E8F0;
    --border-input: #CBD5E1;
    --border-focus: #1685FF;
    
    --primary-accent: #1685FF;
    --primary-hover: #0D76E8;
    --primary-glow: rgba(22, 133, 255, 0.18);
    
    --text-heading: #0F172A;
    --text-body: #475569;
    --text-muted: #94A3B8;
    
    --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
    --shadow-input: inset 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-button: 0 4px 14px 0 rgba(22, 133, 255, 0.3);
  }
}

/* ==========================================================================
   Base & Reset
   ========================================================================== */

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-main);
  color: var(--text-body);
  font-family: var(--font-family);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.25s ease, color 0.25s ease;
}

input, button, textarea, select {
  font-family: var(--font-family);
}

a {
  color: var(--primary-accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */

.header {
  width: 100%;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-main);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: rgba(13, 15, 18, 0.88);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

body.theme-light .header {
  background-color: rgba(248, 250, 252, 0.88);
}

@media (prefers-color-scheme: light) {
  body:not(.theme-dark) .header {
    background-color: rgba(248, 250, 252, 0.88);
  }
}

.header__container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header__logo a {
  display: flex;
  align-items: center;
  text-decoration: none;
  gap: 8px;
}

/* Logo Theme Switch */
.logo-svg {
  display: block;
  height: 42px;
  width: auto;
  transition: transform 0.2s ease;
}

.logo-svg:hover {
  transform: scale(1.02);
}

.logo-svg--light {
  display: none;
}

.logo-svg--dark {
  display: block;
}

body.theme-light .logo-svg--light {
  display: block;
}

body.theme-light .logo-svg--dark {
  display: none;
}

@media (prefers-color-scheme: light) {
  body:not(.theme-dark) .logo-svg--light {
    display: block;
  }
  body:not(.theme-dark) .logo-svg--dark {
    display: none;
  }
}

.header__right {
  display: flex;
  align-items: center;
  gap: 20px;
}

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

.nav-link {
  color: var(--text-body);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.nav-link:hover {
  color: var(--text-heading);
  background-color: var(--bg-surface);
}

.nav-link.active {
  color: var(--primary-accent);
  background-color: rgba(22, 133, 255, 0.1);
}

/* Theme Toggle Button */
.theme-toggle-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-body);
  border-radius: var(--radius-sm);
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

.theme-toggle-btn:hover {
  color: var(--text-heading);
  border-color: var(--primary-accent);
  background: var(--bg-card-hover);
}

.theme-icon--moon {
  display: block;
}

.theme-icon--sun {
  display: none;
}

body.theme-light .theme-icon--moon {
  display: none;
}

body.theme-light .theme-icon--sun {
  display: block;
}

@media (prefers-color-scheme: light) {
  body:not(.theme-dark) .theme-icon--moon {
    display: none;
  }
  body:not(.theme-dark) .theme-icon--sun {
    display: block;
  }
}

/* Mobile Hamburger Menu */
.mobile-menu-btn {
  display: none;
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-heading);
  border-radius: var(--radius-sm);
  width: 38px;
  height: 38px;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

/* ==========================================================================
   Main Page Layout
   ========================================================================== */

.main-content {
  flex: 1;
  width: 100%;
}

.page-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.section-view {
  display: none;
}

.section-view.active {
  display: block;
}

/* ==========================================================================
   Hero & Converter Section
   ========================================================================== */

.hero-section {
  padding: 64px 0 48px 0;
  text-align: center;
}

.hero__header {
  max-width: 640px;
  margin: 0 auto 36px auto;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 500;
  color: var(--primary-accent);
  background: rgba(22, 133, 255, 0.1);
  border: 1px solid rgba(22, 133, 255, 0.2);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
}

.hero__title {
  color: var(--text-heading);
  font-size: 40px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 14px;
}

.hero__subtitle {
  color: var(--text-body);
  font-size: 17px;
  line-height: 1.5;
}

/* ==========================================================================
   Converter Card
   ========================================================================== */

.converter-wrapper {
  max-width: var(--converter-max);
  margin: 0 auto;
}

.converter-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-card);
  text-align: left;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.converter-card:hover {
  border-color: rgba(22, 133, 255, 0.3);
}

.converter-label-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.converter-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Input & Convert Action Group */
.converter-input-group {
  background-color: var(--bg-input);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-md);
  padding: 6px 6px 6px 14px;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: all 0.2s ease;
}

.converter-input-group:focus-within {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.input-icon {
  color: var(--text-muted);
  flex-shrink: 0;
  display: flex;
  align-items: center;
}

.converter-input {
  background: transparent;
  border: none;
  color: var(--text-heading);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.5;
  width: 100%;
  outline: none;
  padding: 8px 0;
}

.converter-input::placeholder {
  color: var(--text-muted);
  font-size: 15px;
}

.converter-submit-btn {
  background-color: var(--primary-accent);
  color: #FFFFFF;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  height: 46px;
  padding: 0 24px;
  cursor: pointer;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow-button);
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.converter-submit-btn:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
}

.converter-submit-btn:active {
  transform: translateY(0);
}

/* Format Segmented Controller */
.converter-options {
  margin-top: 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.format-segmented-group {
  display: inline-flex;
  background-color: var(--bg-input);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-sm);
  padding: 3px;
  gap: 3px;
}

.format-btn {
  background: transparent;
  border: none;
  color: var(--text-body);
  font-size: 13px;
  font-weight: 600;
  padding: 6px 16px;
  border-radius: 6px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all 0.15s ease;
}

.format-btn:hover {
  color: var(--text-heading);
}

.format-btn.active {
  background-color: var(--bg-card);
  color: var(--primary-accent);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.15);
}

.format-helper-text {
  font-size: 13px;
  color: var(--text-muted);
}

/* Validation Alert Banner */
.validation-message {
  margin-top: 14px;
  padding: 10px 14px;
  background-color: var(--error-bg);
  border: 1px solid rgba(239, 68, 68, 0.3);
  border-radius: var(--radius-sm);
  color: #F87171;
  font-size: 13px;
  display: none;
  align-items: center;
  gap: 8px;
}

.validation-message.active {
  display: flex;
}

/* Dynamic State Styles (Progress / Ready / Error) */
.state-container {
  display: none;
  padding: 16px 0;
}

.state-container.active {
  display: block;
}

/* Progress State */
.progress-box {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.progress-header {
  display: flex;
  align-items: center;
  gap: 12px;
}

.progress-spinner {
  width: 20px;
  height: 20px;
  border: 2px solid rgba(22, 133, 255, 0.2);
  border-top-color: var(--primary-accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  flex-shrink: 0;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.progress-status-text {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-heading);
}

.progress-bar-wrapper {
  width: 100%;
  height: 6px;
  background-color: var(--bg-surface);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  width: 25%;
  background-color: var(--primary-accent);
  border-radius: var(--radius-full);
  transition: width 0.3s ease;
  animation: pulse-progress 1.5s ease-in-out infinite alternate;
}

@keyframes pulse-progress {
  from { opacity: 0.8; }
  to { opacity: 1; }
}

/* Ready State */
.ready-box {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.ready-media-meta {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  background: var(--bg-input);
  padding: 14px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}

.media-icon-badge {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background-color: rgba(22, 133, 255, 0.12);
  color: var(--primary-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.ready-info {
  flex: 1;
  min-width: 0;
}

.ready-badge {
  display: inline-block;
  font-size: 11px;
  font-weight: 700;
  color: var(--success);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 2px;
}

.ready-title {
  color: var(--text-heading);
  font-size: 16px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.ready-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-download {
  flex: 1;
  min-width: 180px;
  background-color: var(--primary-accent);
  color: #FFFFFF;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  box-shadow: var(--shadow-button);
  transition: all 0.2s ease;
}

.btn-download:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
}

.btn-convert-another {
  background-color: transparent;
  border: 1px solid var(--border-input);
  color: var(--text-body);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 500;
  height: 48px;
  padding: 0 20px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-convert-another:hover {
  color: var(--text-heading);
  border-color: var(--border-focus);
  background-color: var(--bg-surface);
}

/* Error State */
.error-box {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.error-banner {
  display: flex;
  align-items: center;
  gap: 12px;
  background-color: var(--error-bg);
  border: 1px solid rgba(239, 68, 68, 0.3);
  padding: 14px 16px;
  border-radius: var(--radius-md);
  color: #F87171;
  font-size: 14px;
}

.btn-back {
  align-self: flex-start;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-input);
  color: var(--text-heading);
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-back:hover {
  border-color: var(--border-focus);
}

/* Trust Indicator Strip */
.trust-strip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-top: 24px;
  font-size: 13px;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.trust-item svg {
  color: var(--primary-accent);
}

/* ==========================================================================
   Section Styling & Headers
   ========================================================================== */

.page-section {
  padding: 72px 0;
  border-top: 1px solid var(--border-subtle);
}

.section-intro {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 48px auto;
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--primary-accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.section-title {
  color: var(--text-heading);
  font-size: 30px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 12px;
}

.section-description {
  color: var(--text-body);
  font-size: 16px;
}

/* ==========================================================================
   How It Works (Steps)
   ========================================================================== */

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

.step-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  position: relative;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.step-card:hover {
  transform: translateY(-2px);
  border-color: rgba(22, 133, 255, 0.3);
}

.step-number {
  position: absolute;
  top: 20px;
  right: 20px;
  font-size: 28px;
  font-weight: 700;
  color: var(--text-muted);
  opacity: 0.25;
}

.step-icon-wrapper {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: rgba(22, 133, 255, 0.1);
  color: var(--primary-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.step-card h3 {
  color: var(--text-heading);
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.step-card p {
  color: var(--text-body);
  font-size: 14px;
  line-height: 1.6;
}

/* ==========================================================================
   Features Grid
   ========================================================================== */

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  align-items: flex-start;
  gap: 18px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-2px);
  border-color: rgba(22, 133, 255, 0.3);
}

.feature-icon-wrapper {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: rgba(22, 133, 255, 0.1);
  color: var(--primary-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.feature-content h3 {
  color: var(--text-heading);
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
}

.feature-content p {
  color: var(--text-body);
  font-size: 14px;
  line-height: 1.6;
}

/* ==========================================================================
   FAQ Accordions
   ========================================================================== */

.faq-container {
  max-width: 760px;
  margin: 0 auto;
}

.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.accordion-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.accordion-item:hover {
  border-color: rgba(22, 133, 255, 0.3);
}

.accordion-header {
  width: 100%;
  background: transparent;
  border: none;
  color: var(--text-heading);
  font-size: 16px;
  font-weight: 600;
  text-align: left;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  cursor: pointer;
}

.accordion-icon {
  width: 18px;
  height: 18px;
  color: var(--text-muted);
  transition: transform 0.25s ease, color 0.2s ease;
  flex-shrink: 0;
}

.accordion-item.open .accordion-icon {
  transform: rotate(180deg);
  color: var(--primary-accent);
}

.accordion-body {
  padding: 0 24px 20px 24px;
  color: var(--text-body);
  font-size: 15px;
  line-height: 1.65;
  display: none;
}

.accordion-item.open .accordion-body {
  display: block;
}

/* ==========================================================================
   Bookmarklet Page / Section View
   ========================================================================== */

.standalone-view {
  padding: 48px 0 64px 0;
}

.bookmarklet-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-top: 24px;
}

.bookmarklet-actions {
  display: flex;
  gap: 16px;
  margin: 20px 0;
  flex-wrap: wrap;
}

.bookmarklet-pill {
  background: var(--primary-accent);
  color: #FFFFFF;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  cursor: grab;
  box-shadow: var(--shadow-button);
}

.bookmarklet-pill:hover {
  color: #FFFFFF;
  background: var(--primary-hover);
}

.code-snippet-box {
  background: var(--bg-input);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-sm);
  padding: 14px;
  width: 100%;
  color: var(--text-heading);
  font-family: monospace;
  font-size: 13px;
  resize: none;
  outline: none;
  height: 80px;
  margin-top: 10px;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
  border-top: 1px solid var(--border-subtle);
  background: var(--bg-main);
  padding: 56px 0 32px 0;
  margin-top: auto;
}

.footer__grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.footer__brand {
  max-width: 320px;
}

.footer__desc {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 12px;
  line-height: 1.6;
}

.footer__nav-group h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-heading);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 14px;
}

.footer__links-col {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer__links-col a {
  color: var(--text-body);
  font-size: 14px;
  transition: color 0.2s ease;
}

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

.footer__bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-muted);
  flex-wrap: wrap;
  gap: 12px;
}

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

@media only screen and (max-width: 900px) {
  .steps-grid {
    grid-template-columns: 1fr;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
  }
}

@media only screen and (max-width: 640px) {
  .header__container {
    padding: 14px 16px;
  }
  
  .header__nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    border-bottom: 1px solid var(--border-subtle);
    padding: 16px;
    flex-direction: column;
    align-items: stretch;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
  }

  .header__nav.open {
    display: flex;
  }
  
  .mobile-menu-btn {
    display: flex;
  }

  .hero-section {
    padding: 40px 0 32px 0;
  }

  .hero__title {
    font-size: 28px;
  }

  .hero__subtitle {
    font-size: 15px;
  }

  .converter-card {
    padding: 20px 16px;
  }

  .converter-input-group {
    flex-direction: column;
    padding: 8px;
  }

  .converter-submit-btn {
    width: 100%;
    justify-content: center;
  }

  .converter-options {
    flex-direction: column;
    align-items: flex-start;
  }

  .format-segmented-group {
    width: 100%;
  }

  .format-btn {
    flex: 1;
    justify-content: center;
  }

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

  .btn-download,
  .btn-convert-another {
    width: 100%;
  }

  .page-section {
    padding: 48px 0;
  }

  .footer__grid {
    flex-direction: column;
    gap: 32px;
  }
}