/* main.css — extracted verbatim from main.html's original inline <style>; logic/behavior unchanged, only relocated */
/* Premium Design Tokens & System Variables */
    :root {
      --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      --radius-card: 20px;
      --radius-pill: 30px;
      --radius-btn: 12px;
      --radius-input: 12px;
      
      /* Light Mode Palette */
      --bg-surface: #f5f7fa;
      --bg-header: rgba(255, 255, 255, 0.75);
      --card-bg: #ffffff;
      --card-border: rgba(0, 0, 0, 0.05);
      --text-main: #1c1c1e;
      --text-muted: #68686e;
      --glass-blur: blur(20px);
      
      /* Accent Colors (Premium UI OS Framework) */
      --color-primary: #0071e3;
      --color-primary-hover: #0077ed;
      --color-secondary: #e8e8ed;
      --color-success: #34c759;
      --color-danger: #ff3b30;
      --color-accent-bg: rgba(0, 113, 227, 0.06);
      --gradient-hero: linear-gradient(135deg, #0071e3, #5856d6, #af52de);
      
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.04);
      --shadow-lg: 0 16px 48px rgba(0,0,0,0.06);
      --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

    [data-theme="dark"] {
      /* Dark Mode Palette */
      --bg-surface: #0a0a0c;
      --bg-header: rgba(22, 22, 26, 0.75);
      --card-bg: #16161a;
      --card-border: rgba(255, 255, 255, 0.05);
      --text-main: #f5f5f7;
      --text-muted: #949499;
      --glass-blur: blur(20px);
      
      --color-primary: #2f96ec;
      --color-primary-hover: #40a2f5;
      --color-secondary: #2c2c2e;
      --color-success: #30d158;
      --color-danger: #ff453a;
      --color-accent-bg: rgba(47, 150, 236, 0.12);
      --gradient-hero: linear-gradient(135deg, #1d6fa5, #4338ca, #6b21a8);
      
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.2);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.3);
      --shadow-lg: 0 16px 40px rgba(0,0,0,0.4);
    }

    /* Base Architecture Layout Optimization */
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-family);
      background-color: var(--bg-surface);
      color: var(--text-main);
      min-height: 100vh;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-start;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
      transition: background-color 0.4s ease, color 0.4s ease;
      padding-top: 76px;
    }

    .studio-container {
      width: 100%;
      max-width: 1400px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* Premium Sticky Header Redesign */
    .sticky-header-container {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 70px;
      background: var(--bg-header);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border-bottom: 1px solid var(--card-border);
      z-index: 1000;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition);
    }

    .sticky-header-wrapper {
      width: 100%;
      max-width: 1400px;
      padding: 0 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .header-left-cluster, .header-right-cluster {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .action-btn-node {
      background: transparent;
      border: none;
      color: var(--text-main);
      width: 42px;
      height: 42px;
      border-radius: 50%;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition);
      font-size: 1.25rem;
    }

    .action-btn-node:hover {
      background: var(--color-secondary);
      transform: scale(1.05);
    }

    .brand-logo-cluster {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
      color: var(--text-main);
    }

    .logo-vector-icon {
      width: 32px;
      height: 32px;
      background: var(--gradient-hero);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-weight: 800;
      font-size: 0.95rem;
      letter-spacing: -0.5px;
    }

    .brand-logo-cluster h1 {
      font-size: 1.25rem;
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    /* Slide Menu Drawer System Layout */
    .drawer-overlay-shield {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(0, 0, 0, 0.4);
      z-index: 2000;
      opacity: 0;
      pointer-events: none;
      backdrop-filter: blur(4px);
      transition: opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }

    .drawer-overlay-shield.active {
      opacity: 1;
      pointer-events: auto;
    }

    .slide-drawer-panel {
      position: fixed;
      top: 0;
      left: -320px;
      width: 320px;
      height: 100%;
      background: var(--card-bg);
      border-right: 1px solid var(--card-border);
      z-index: 2001;
      box-shadow: var(--shadow-lg);
      display: flex;
      flex-direction: column;
      transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    }

    .drawer-overlay-shield.active .slide-drawer-panel {
      transform: translateX(320px);
    }

    .drawer-header-segment {
      padding: 24px;
      border-bottom: 1px solid var(--card-border);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .drawer-nav-container {
      flex: 1;
      overflow-y: auto;
      padding: 16px;
    }

    .drawer-section-divider {
      font-size: 0.7rem;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--text-muted);
      margin: 16px 8px 8px 8px;
      font-weight: 700;
    }

    .drawer-nav-link {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 12px;
      color: var(--text-main);
      text-decoration: none;
      font-size: 0.92rem;
      font-weight: 500;
      border-radius: var(--radius-btn);
      transition: var(--transition);
    }

    .drawer-nav-link:hover {
      background: var(--color-accent-bg);
      color: var(--color-primary);
    }

    /* Hero Section Component Expansion */
    .hero-station-premium {
      text-align: center;
      padding: 60px 24px 40px 24px;
      border-radius: var(--radius-card);
      background: var(--card-bg);
      box-shadow: var(--shadow-md);
      border: 1px solid var(--card-border);
      margin-top: 32px;
      margin-bottom: 40px;
      position: relative;
      overflow: hidden;
    }

    .hero-station-premium::before {
      content: '';
      position: absolute;
      top: -150px;
      left: 50%;
      transform: translateX(-50%);
      width: 600px;
      height: 300px;
      background: var(--gradient-hero);
      opacity: 0.05;
      filter: blur(100px);
      border-radius: 50%;
      pointer-events: none;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      background: var(--color-accent-bg);
      color: var(--color-primary);
      padding: 6px 16px;
      border-radius: 30px;
      font-size: 0.8rem;
      font-weight: 600;
      margin-bottom: 20px;
    }

    .hero-station-premium h2 {
      font-size: 2.5rem;
      font-weight: 800;
      letter-spacing: -1px;
      line-height: 1.2;
      margin-bottom: 12px;
    }

    .hero-station-premium p {
      font-size: 1.05rem;
      color: var(--text-muted);
      max-width: 650px;
      margin: 0 auto 32px auto;
      line-height: 1.5;
    }

    .hero-stats-grid {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
      margin-bottom: 32px;
    }

    .hero-stat-pill {
      background: var(--bg-surface);
      border: 1px solid var(--card-border);
      padding: 10px 20px;
      border-radius: var(--radius-pill);
      font-size: 0.85rem;
      color: var(--text-main);
      font-weight: 600;
      box-shadow: var(--shadow-sm);
    }

    /* Enhanced Search Engine Layout */
    .search-wrapper-premium {
      position: relative;
      width: 100%;
      max-width: 550px;
      margin: 0 auto;
    }

    .search-icon-node {
      position: absolute;
      left: 18px;
      top: 50%;
      transform: translateY(-50%);
      color: var(--text-muted);
      font-size: 1.1rem;
      pointer-events: none;
    }

    .search-input-premium {
      width: 100%;
      padding: 16px 20px 16px 52px;
      border-radius: var(--radius-pill);
      border: 1px solid var(--card-border);
      background: var(--bg-surface);
      color: var(--text-main);
      font-size: 0.98rem;
      font-family: var(--font-family);
      outline: none;
      box-shadow: inset 0 1px 3px rgba(0,0,0,0.02);
      transition: var(--transition);
    }

    .search-input-premium:focus {
      border-color: var(--color-primary);
      background: var(--card-bg);
      box-shadow: 0 0 0 4px var(--color-accent-bg);
    }

    /* Layout Sub-Navigation Bar */
    .floating-navigation-bar {
      display: flex;
      overflow-x: auto;
      gap: 10px;
      padding: 12px 4px;
      margin-bottom: 32px;
      scrollbar-width: none;
      -webkit-overflow-scrolling: touch;
    }

    .floating-navigation-bar::-webkit-scrollbar {
      display: none;
    }

    .nav-pill {
      white-space: nowrap;
      text-decoration: none;
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      color: var(--text-muted);
      padding: 10px 20px;
      border-radius: var(--radius-pill);
      font-size: 0.88rem;
      font-weight: 600;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .nav-pill:hover, .nav-pill.active {
      background: var(--color-primary);
      color: #ffffff;
      border-color: var(--color-primary);
      transform: translateY(-1px);
    }

    /* Premium Modular Calculator Cards (Dynamic Grid Architecture) */
    .modules-area {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
      margin-bottom: 60px;
    }

    .premium-modular-row {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-md);
      display: flex;
      flex-direction: column;
      gap: 24px;
      position: relative;
      transition: transform 0.3s cubic-bezier(0.25, 1, 0.5, 1), box-shadow 0.3s ease;
    }

    .premium-modular-row:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
    }

    .premium-modular-row.hidden-module {
      display: none !important;
    }

    .card-top-identity-row {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
    }

    .identity-left-stack {
      display: flex;
      flex-direction: column;
    }

    .studio-step-tag {
      font-size: 0.72rem;
      text-transform: uppercase;
      letter-spacing: 1.2px;
      color: var(--color-primary);
      font-weight: 700;
      margin-bottom: 6px;
    }

    .premium-modular-row h3 {
      font-size: 1.4rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      margin-bottom: 4px;
    }

    .tool-description {
      font-size: 0.9rem;
      color: var(--text-muted);
      line-height: 1.5;
    }

    .card-favorite-toggle {
      background: none;
      border: none;
      font-size: 1.2rem;
      cursor: pointer;
      color: var(--text-muted);
      transition: var(--transition);
    }

    .card-favorite-toggle.favorited {
      color: #ffb800;
      transform: scale(1.1);
    }

    /* Action Panels / Tool Specs Elements */
    .btn-info {
      background: var(--bg-surface);
      border: 1px solid var(--card-border);
      color: var(--text-muted);
      padding: 6px 12px;
      border-radius: 8px;
      font-size: 0.78rem;
      font-weight: 600;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      align-self: flex-start;
      transition: var(--transition);
    }

    .btn-info:hover {
      background: var(--color-secondary);
      color: var(--text-main);
    }

    .info-panel {
      background: var(--bg-surface);
      border-radius: var(--radius-input);
      padding: 14px 18px;
      font-size: 0.85rem;
      color: var(--text-muted);
      line-height: 1.5;
      border-left: 4px solid var(--color-primary);
      display: none;
      animation: fadeIn 0.3s ease;
    }

    /* Core Input Components Architecture Styles */
    .grid-inputs-vertical {
      display: flex;
      flex-direction: column;
      gap: 16px;
      margin-bottom: 20px;
    }

    .grid-inputs-row-mesh {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 10px;
      margin-bottom: 20px;
    }

    .input-wrapper {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .input-wrapper label {
      font-size: 0.75rem;
      font-weight: 700;
      color: var(--text-muted);
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .input-wrapper input, .input-wrapper select {
      width: 100%;
      background: var(--bg-surface);
      border: 1px solid var(--card-border);
      color: var(--text-main);
      padding: 12px 16px;
      border-radius: var(--radius-input);
      font-family: var(--font-family);
      font-size: 0.95rem;
      outline: none;
      transition: var(--transition);
    }

    .input-wrapper input:focus, .input-wrapper select:focus {
      border-color: var(--color-primary);
      background: var(--card-bg);
      box-shadow: 0 0 0 3px var(--color-accent-bg);
    }

    /* Core Action Button Paddings Redesigns */
    .action-group-vertical {
      display: flex;
      gap: 12px;
    }

    .btn-primary, .btn-secondary {
      flex: 1;
      padding: 14px 20px;
      border-radius: var(--radius-btn);
      font-family: var(--font-family);
      font-size: 0.92rem;
      font-weight: 600;
      border: none;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: var(--transition);
    }

    .btn-primary {
      background: var(--color-primary);
      color: #ffffff;
      box-shadow: 0 4px 12px rgba(0, 113, 227, 0.15);
    }

    .btn-primary:hover {
      background: var(--color-primary-hover);
      transform: translateY(-1px);
      box-shadow: 0 6px 16px rgba(0, 113, 227, 0.25);
    }

    .btn-secondary {
      background: var(--bg-surface);
      color: var(--color-danger);
      border: 1px solid var(--card-border);
    }

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

    /* Dashboard Metrics & Outputs Sections Redesigns */
    .panel-dashboard-analytics {
      background: var(--bg-surface);
      border-radius: var(--radius-card);
      padding: 24px;
      border: 1px dashed var(--card-border);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .panel-title-badge h4 {
      font-size: 0.75rem;
      text-transform: uppercase;
      letter-spacing: 0.8px;
      color: var(--text-muted);
    }

    .dashboard-empty-state {
      font-size: 0.88rem;
      color: var(--text-muted);
      text-align: center;
      padding: 20px 0;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 10px;
    }

    .dashboard-empty-state-icon {
      font-size: 1.8rem;
      opacity: 0.6;
    }

    .result-display {
      font-size: 1.6rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--color-success);
      word-break: break-word;
      animation: scaleIn 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    .result-action-bar {
      display: flex;
      gap: 8px;
      flex-wrap: wrap;
      margin-top: 4px;
    }

    .btn-action-pill {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      color: var(--text-main);
      padding: 6px 12px;
      border-radius: 8px;
      font-size: 0.75rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 6px;
      transition: var(--transition);
    }

    .btn-action-pill:hover {
      background: var(--color-secondary);
    }

    .smart-insights-deck-card, .how-it-works-trace {
      padding-top: 16px;
      border-top: 1px solid var(--card-border);
      font-size: 0.82rem;
      color: var(--text-muted);
      line-height: 1.5;
    }

    .smart-insights-deck-card h5, .how-it-works-trace h5 {
      font-size: 0.8rem;
      color: var(--text-main);
      margin-bottom: 6px;
      font-weight: 700;
    }

    .trace-formula {
      display: block;
      font-family: monospace;
      background: var(--card-bg);
      padding: 8px 12px;
      border-radius: 6px;
      margin: 6px 0;
      color: var(--color-primary);
      border: 1px solid var(--card-border);
    }

    /* Snapshot Layout Cards Framework Designs */
    .panel-snapshot-share-studio {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .social-wrapped-snapshot-card {
      background: var(--gradient-hero);
      border-radius: var(--radius-card);
      padding: 28px;
      color: #ffffff;
      position: relative;
      overflow: hidden;
      box-shadow: var(--shadow-md);
    }

    .wrapped-watermark {
      position: absolute;
      right: -15px;
      bottom: -15px;
      font-size: 4.5rem;
      font-weight: 900;
      opacity: 0.06;
      letter-spacing: -2px;
      pointer-events: none;
    }

    .wrapped-tool-tag {
      font-size: 0.75rem;
      text-transform: uppercase;
      letter-spacing: 1.2px;
      opacity: 0.8;
      margin-bottom: 12px;
      font-weight: 700;
    }

    .wrapped-main-stat {
      font-size: 1.8rem;
      font-weight: 800;
      margin-bottom: 8px;
      letter-spacing: -0.5px;
    }

    .wrapped-sub-metrics {
      font-size: 0.88rem;
      opacity: 0.9;
      line-height: 1.45;
    }

    .wrapped-footer-branding {
      font-size: 0.7rem;
      margin-top: 24px;
      opacity: 0.6;
      font-weight: 500;
    }

    .social-share-mesh-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 8px;
    }

    .btn-share-node {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      color: var(--text-main);
      padding: 10px 4px;
      border-radius: 8px;
      font-size: 0.75rem;
      font-weight: 600;
      cursor: pointer;
      text-align: center;
      transition: var(--transition);
    }

    .btn-share-node:hover {
      background: var(--color-secondary);
      transform: translateY(-1px);
    }

    /* Modal Overlay & App Settings Layout Structure */
    .settings-modal-overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(0, 0, 0, 0.4);
      z-index: 3000;
      opacity: 0;
      pointer-events: none;
      backdrop-filter: blur(5px);
      display: flex;
      align-items: center;
      justify-content: center;
      transition: opacity 0.3s ease;
    }

    .settings-modal-overlay.active {
      opacity: 1;
      pointer-events: auto;
    }

    .settings-card-frame {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 32px;
      width: 100%;
      max-width: 500px;
      box-shadow: var(--shadow-lg);
      transform: scale(0.95);
      transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    .settings-modal-overlay.active .settings-card-frame {
      transform: scale(1);
    }

    .settings-header-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 24px;
    }

    .settings-options-stack {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    /* Quick Action Floating Controls System */
    .floating-hub-controls {
      position: fixed;
      bottom: 32px;
      right: 32px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      z-index: 999;
    }

    .hub-action-trigger {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      color: var(--text-main);
      box-shadow: var(--shadow-md);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.2rem;
      transition: var(--transition);
    }

    .hub-action-trigger:hover {
      transform: translateY(-2px);
      background: var(--color-primary);
      color: #fff;
      box-shadow: var(--shadow-lg);
    }

    /* Modern Footer Component Section Redesign */
    footer {
      background: var(--card-bg);
      border-top: 1px solid var(--card-border);
      width: 100%;
      padding: 48px 24px;
      margin-top: auto;
    }

    .footer-content-wrapper {
      width: 100%;
      max-width: 1400px;
      margin: 0 auto;
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }

    .footer-brand-info h4 {
      font-size: 1.2rem;
      margin-bottom: 12px;
      font-weight: 700;
    }

    .footer-brand-info p {
      font-size: 0.88rem;
      color: var(--text-muted);
      line-height: 1.6;
    }

    .footer-links-column {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .footer-links-column h5 {
      font-size: 0.85rem;
      text-transform: uppercase;
      letter-spacing: 0.8px;
      color: var(--text-muted);
      margin-bottom: 4px;
    }

    .footer-links-column a {
      color: var(--text-main);
      text-decoration: none;
      font-size: 0.88rem;
      transition: var(--transition);
    }

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

    .footer-bottom-bar {
      width: 100%;
      max-width: 1400px;
      margin: 40px auto 0 auto;
      padding-top: 24px;
      border-top: 1px solid var(--card-border);
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 0.8rem;
      color: var(--text-muted);
      flex-wrap: wrap;
      gap: 16px;
    }

    /* Core System Keyframe Animations Presets */
    @keyframes fadeIn {
      from { opacity: 0; transform: translateY(6px); }
      to { opacity: 1; transform: translateY(0); }
    }

    @keyframes scaleIn {
      from { transform: scale(0.97); opacity: 0; }
      to { transform: scale(1); opacity: 1; }
    }

    /* System Responsive Layout Media Queries Engine */
    @media (max-width: 1024px) {
      .modules-area { grid-template-columns: repeat(2, 1fr); gap: 24px; }
      .hero-station-premium h2 { font-size: 2.2rem; }
    }

    @media (max-width: 768px) {
      .modules-area { grid-template-columns: 1fr; gap: 20px; }
      .footer-content-wrapper { grid-template-columns: 1fr; gap: 32px; }
      .hero-station-premium h2 { font-size: 1.8rem; }
      body { padding-top: 70px; }
    }

    @media (max-width: 480px) {
      .grid-inputs-row-mesh { grid-template-columns: repeat(2, 1fr); }
      .social-share-mesh-grid { grid-template-columns: repeat(2, 1fr); }
      .hero-stats-grid { flex-direction: column; align-items: stretch; }
      .action-group-vertical { flex-direction: column; }
      .sticky-header-wrapper { padding: 0 16px; }
      .brand-logo-cluster h1 { display: none; }
    }