/* FFRETT TECH - Home Energy Systems Stylesheet */

    /* Reset and Base Styles */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    :root {
      /* Primary Colors - Clean Energy Theme */
      --primary-green: #2ECC71;
      --primary-dark: #27AE60;
      --accent-blue: #3498DB;
      --accent-orange: #F39C12;
      
      /* Neutral Colors */
      --white: #FFFFFF;
      --light-gray: #F8F9FA;
      --medium-gray: #6C757D;
      --dark-gray: #343A40;
      --black: #1A1A1A;
      
      /* Typography */
      --font-primary: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
      --font-secondary: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
      
      /* Spacing */
      --container-max-width: 1200px;
      --section-padding: 80px 0;
      --border-radius: 12px;
      --border-radius-small: 6px;
      
      /* Shadows */
      --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.1);
      --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.15);
      --shadow-heavy: 0 8px 32px rgba(0, 0, 0, 0.2);
      
      /* Transitions */
      --transition-fast: 0.2s ease;
      --transition-medium: 0.3s ease;
      --transition-slow: 0.5s ease;
    }

    /* Typography */
    @import url('https://fonts.googleapis.com/css2?family=Noto+Sans+TC:wght@300;400;500;700;900&family=Inter:wght@300;400;500;600;700&display=swap');

    body {
      font-family: var(--font-primary);
      font-size: 16px;
      line-height: 1.6;
      color: var(--dark-gray);
      background-color: var(--white);
      overflow-x: hidden;
    }

    /* Container */
    .container {
      max-width: var(--container-max-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* Header & Navigation */
    header{
      position:fixed;top:0;left:0;right:0;
      background:#000;color:#fff;z-index:1000;
      transition:all .3s;
    }
    nav.container{
      display:flex;align-items:center;justify-content:space-between;
      padding:15px 20px;
    }
    nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 15px 20px;
    }

    .logo {
      text-decoration: none;
      display: flex;
      align-items: center;
      transition: transform var(--transition-fast);
    }

    .logo:hover {
      transform: translateY(-2px);
    }

    .logo-image {
      height: 40px;
      width: auto;
    }

    .nav-links {
      display: flex;
      list-style: none;
      gap: 32px;
      align-items: center;
    }

    .nav-links a {
      text-decoration: none;
      color: white;
      font-weight: 500;
      font-size: 15px;
      transition: all var(--transition-fast);
      position: relative;
      padding: 8px 0;
    }

    .nav-links a:hover {
      color: var(--accent-blue);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-blue);
      transition: width var(--transition-medium);
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .cta-nav {
      background: var(--accent-blue);
      color: var(--white) !important;
      padding: 12px 24px !important;
      border-radius: var(--border-radius-small);
      font-weight: 600;
      box-shadow: var(--shadow-light);
      transition: all var(--transition-medium);
    }

    .cta-nav::after {
      display: none;
    }

    .cta-nav:hover {
      background: #2980b9;
      transform: translateY(-2px);
      box-shadow: var(--shadow-medium);
    }

    /* Main Content - FIXED: Remove padding-top */
    main {
      padding-top: 0;
    }

    /* Hero Section - FIXED: Account for header height */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      position: relative;
      overflow: hidden;
      background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
      margin-top: 0;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      padding: 40px 20px;
      animation: fadeInUp 1s ease-out;
    }

    .hero h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 900;
      color: var(--white);
      margin-bottom: 24px;
    }

    .subtitle {
      font-size: clamp(1.1rem, 2.5vw, 1.5rem);
      color: var(--white);
      font-weight: 400;
      margin-bottom: 40px;
      opacity: 1;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
      margin-top: 40px;
    }

    /* Panel Styles */
    .panel {
      min-height: 100vh;
      background-repeat: no-repeat;
      background-size: cover;
      background-position: center;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      margin: 0;
      padding: 60px 0;
    }

    .panel-overlay {
      position: absolute;
      inset: 0;
      background: rgba(0, 0, 0, 0.5);
      z-index: 1;
    }

    .panel-content {
      position: relative;
      z-index: 2;
      text-align: center;
      color: var(--white);
      max-width: 1000px;
      padding: 40px 20px;
      margin: 0 auto;
    }

    .panel-content h2 {
      font-size: clamp(2.5rem, 4vw, 3.5rem);
      font-weight: 700;
      margin-bottom: 20px;
      font-family: var(--font-primary);
      color: var(--white);
      text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.7);
    }

    .panel-content h3 {
      font-size: clamp(1.2rem, 2.5vw, 1.8rem);
      font-weight: 400;
      margin-bottom: 40px;
      opacity: 0.9;
      font-family: var(--font-secondary);
      color: rgba(255, 255, 255, 0.9);
      text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
    }

    /* Services Grid */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
      gap: 30px;
      margin-top: 50px;
      z-index: 3;
      position: relative;
    }

    .service-card {
      background: rgba(255, 255, 255, 0.95);
      border-radius: var(--border-radius);
      padding: 30px;
      box-shadow: var(--shadow-heavy);
      transition: all var(--transition-medium);
      position: relative;
      overflow: hidden;
      backdrop-filter: blur(10px);
    }

    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
    }

    .service-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 4px;
      background: linear-gradient(90deg, var(--primary-green), var(--accent-blue));
    }

    .service-number {
      position: absolute;
      top: 20px;
      right: 20px;
      font-size: 36px;
      font-weight: 900;
      color: rgba(52, 58, 64, 0.1);
      font-family: var(--font-secondary);
      z-index: 1;
    }

    .service-icon {
      font-size: 48px;
      margin-bottom: 20px;
      display: block;
    }

    .service-card h4 {
      font-size: 22px;
      font-weight: 700;
      color: var(--dark-gray);
      margin-bottom: 8px;
      font-family: var(--font-primary);
      z-index: 2;
      position: relative;
    }

    .service-card h5 {
      font-size: 14px;
      font-weight: 500;
      color: var(--primary-green);
      margin-bottom: 20px;
      font-family: var(--font-secondary);
    }

    .service-card p {
      font-size: 15px;
      line-height: 1.7;
      color: var(--medium-gray);
      margin-bottom: 15px;
    }

    .service-content {
      text-align: left;
    }

    /* FAQ Grid */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
      gap: 25px;
      margin-top: 50px;
      text-align: left;
      z-index: 3;
      position: relative;
    }

    .faq-item {
      background: rgba(255, 255, 255, 0.95);
      padding: 30px;
      border-radius: var(--border-radius);
      box-shadow: var(--shadow-heavy);
      transition: all var(--transition-medium);
      backdrop-filter: blur(10px);
    }

    .faq-item:hover {
      transform: translateY(-4px);
      box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
    }

    .faq-item h4 {
      font-size: 18px;
      font-weight: 600;
      color: var(--dark-gray);
      margin-bottom: 15px;
      font-family: var(--font-primary);
    }

    .faq-item p {
      font-size: 15px;
      line-height: 1.7;
      color: var(--medium-gray);
    }

    /* About Content */
    .about-content {
      max-width: 800px;
      margin: 0 auto;
      background: rgba(255, 255, 255, 0.15);
      padding: 40px;
      border-radius: var(--border-radius);
      backdrop-filter: blur(10px);
      box-shadow: var(--shadow-heavy);
      z-index: 2;
      position: relative;
    }

    .about-content p {
      font-size: 18px;
      line-height: 1.8;
      color: var(--white);
      margin-bottom: 20px;
      text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
    }

    /* Button Styles */
    .btn {
      display: inline-block;
      padding: 14px 32px;
      border: none;
      border-radius: var(--border-radius-small);
      font-weight: 600;
      text-decoration: none;
      transition: all var(--transition-medium);
      cursor: pointer;
      font-size: 16px;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-green), var(--primary-dark));
      color: var(--white);
      box-shadow: var(--shadow-light);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: var(--shadow-medium);
    }

    .btn-outline {
      background: rgba(255, 255, 255, 0.1);
      color: var(--white);
      border: 2px solid var(--white);
      backdrop-filter: blur(10px);
    }

    .btn-outline:hover {
      background: var(--white);
      color: var(--dark-gray);
    }

    /* Footer - IMPROVED */
    footer {
      background: linear-gradient(135deg, #1A1A1A 0%, #2C3E50 100%);
      color: var(--white);
      padding: 60px 0 30px;
      margin-top: 0;
      position: relative;
      overflow: hidden;
    }

    footer::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 1px;
      background: linear-gradient(90deg, transparent, var(--accent-blue), transparent);
    }

    .footer-content {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-section h4 {
      font-size: 20px;
      font-weight: 700;
      color: var(--white);
      margin-bottom: 20px;
      font-family: var(--font-primary);
    }

    .footer-section p,
    .footer-section a {
      font-size: 15px;
      line-height: 1.6;
      color: rgba(255, 255, 255, 0.8);
      text-decoration: none;
      transition: color var(--transition-fast);
    }

    .footer-section a:hover {
      color: var(--accent-blue);
    }

    .footer-links {
      list-style: none;
      padding: 0;
    }

    .footer-links li {
      margin-bottom: 10px;
    }

    .footer-links a {
      display: flex;
      align-items: center;
      gap: 10px;
      padding: 5px 0;
    }

    .footer-links a:hover {
      padding-left: 5px;
    }

    .footer-social {
      display: flex;
      gap: 15px;
      margin-top: 20px;
    }

    .footer-social a {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 40px;
      height: 40px;
      background: rgba(255, 255, 255, 0.1);
      border-radius: 50%;
      transition: all var(--transition-medium);
      backdrop-filter: blur(10px);
    }

    .footer-social a:hover {
      background: var(--accent-blue);
      transform: translateY(-2px);
    }

    .footer-bottom {
      text-align: center;
      padding-top: 30px;
      border-top: 1px solid rgba(255, 255, 255, 0.1);
    }

    .footer-bottom p {
      font-size: 14px;
      color: rgba(255, 255, 255, 0.6);
    }
    
    .footer-social{
      display:flex;
      gap:0.75rem;
    }
    .social-link{
      display:inline-flex;
      width:40px;
      height:40px;
      border-radius:50%;
      align-items:center;
      justify-content:center;
      color:#fff;            /* icon color */
      background:#2b2b2b;    /* circle bg */
      transition:opacity .2s, transform .15s;
    }
    .social-link:hover{
      opacity:.8;
      transform:translateY(-2px);
    }

    /* Animations */
    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(30px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    /* Responsive Design */
    @media (max-width: 968px) {
      .services-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 25px;
      }
      
      .faq-grid {
        grid-template-columns: 1fr;
        gap: 20px;
      }

      .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
        text-align: center;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        gap: 20px;
        flex-wrap: wrap;
        justify-content: center;
      }
      
      .hero-buttons {
        flex-direction: column;
        align-items: center;
      }
      
      .services-grid {
        grid-template-columns: 1fr;
        gap: 20px;
        margin-top: 40px;
      }
      
      .faq-grid {
        grid-template-columns: 1fr;
        margin-top: 40px;
      }
      
      nav {
        flex-direction: column;
        gap: 20px;
        padding: 20px;
      }

      .panel-content {
        padding: 30px 15px;
      }

      .panel-content h2 {
        font-size: 2.2rem;
        margin-bottom: 15px;
      }

      .panel-content h3 {
        font-size: 1.3rem;
        margin-bottom: 30px;
      }

      .service-card {
        padding: 25px 20px;
      }
    }

    @media (max-width: 480px) {
      .container {
        padding: 0 15px;
      }
      
      .nav-links {
        flex-direction: column;
        gap: 15px;
      }
      
      .nav-links a {
        font-size: 16px;
      }
      
      .hero-content {
        padding: 20px 15px;
      }
      
      .panel-content {
        padding: 20px 10px;
      }

      .panel-content h2 {
        font-size: 2rem;
      }

      .panel-content h3 {
        font-size: 1.2rem;
      }

      .service-card {
        padding: 20px 15px;
      }

      .service-number {
        font-size: 28px;
        top: 15px;
        right: 15px;
      }

      .faq-grid {
        grid-template-columns: 1fr;
      }

      .faq-item {
        padding: 20px;
      }

      .about-content {
        padding: 25px 20px;
      }

      footer {
        padding: 40px 0 20px;
      }

      .footer-content {
        gap: 25px;
      }
    }

    /* Accessibility */
    @media (prefers-reduced-motion: reduce) {
      * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
      }
    }

    /* Focus states for keyboard navigation */
    a:focus,
    button:focus {
      outline: 2px solid var(--primary-green);
      outline-offset: 2px;
    }
    /* Force 3 cards on desktop */
  #services .panel-content{
    max-width: none !important;
    width: 100% !important;
  }

  @media (min-width:1024px){
    #services .services-grid{
      grid-template-columns: repeat(3, 1fr) !important;
    }
  }

  /* keep mobile behavior */
  @media (max-width:968px){
    #services .services-grid{
      grid-template-columns: 1fr !important;
    }
  }
  /* Hamburger button */
.nav-toggle{
  display:none;
  flex-direction:column;
  gap:6px;
  width:32px;
  height:24px;
  background:none;
  border:0;
  cursor:pointer;
  z-index:1100;
}
.nav-toggle span{
  display:block;
  width:100%;
  height:3px;
  background:#fff;
  transition:transform .25s, opacity .25s;
}

/* Mobile menu panel */
/* Mobile header fix */
@media (max-width:768px){
  nav.container{
    flex-direction: row !important;
    align-items: center !important;
    justify-content: space-between !important;
    gap: 0 !important;
    padding: 12px 16px !important;
  }

  .nav-links{ display:none !important; }          /* hide base list */
  #primary-nav.open{ display:flex !important; }   /* show when toggled */
}

.nav-toggle{ margin-left:auto; } /* push burger to the right */
@media (max-width:768px){
  .nav-toggle{ display:flex !important; }  /* show the burger */
  nav{ flex-direction:row !important; justify-content:space-between !important; gap:0 !important; }
  .nav-links{ display:none !important; }
  #primary-nav.open{ display:flex !important; flex-direction:column; }
}
/* ===== Mobile Nav ===== */
@media (max-width:768px){
  nav.container{
    flex-direction:row !important;
    align-items:center !important;
    justify-content:space-between !important;
    gap:0 !important;
    padding:12px 16px !important;
    position:relative;
    z-index:1200;
  }

  .nav-toggle{
    display:flex !important;
    flex-direction:column;
    gap:6px;
    width:32px;height:24px;
    background:none;border:0;cursor:pointer;
    z-index:1300;
  }
  .nav-toggle span{
    width:100%;height:3px;background:#fff;
    transition:transform .25s, opacity .25s;
  }
  .nav-toggle.active span:nth-child(1){transform:translateY(9px) rotate(45deg);}
  .nav-toggle.active span:nth-child(2){opacity:0;}
  .nav-toggle.active span:nth-child(3){transform:translateY(-9px) rotate(-45deg);}

  /* Drawer */
  #primary-nav{
    position:fixed;
    top:0; right:0; bottom:0;
    width:75%; max-width:320px;
    background:#111;
    padding:96px 32px 32px;
    display:flex; flex-direction:column;
    gap:28px;
    transform:translateX(100%);
    transition:transform .3s ease;
    z-index:1250;
  }
  #primary-nav.open{ transform:translateX(0); }

  #primary-nav a{ color:#fff; font-size:18px; }

  /* Backdrop */
  #nav-backdrop{
    position:fixed;
    inset:0;
    background:rgba(0,0,0,.45);
    opacity:0;
    pointer-events:none;
    transition:opacity .3s;
    z-index:1240;
  }
  #nav-backdrop.show{
    opacity:1;
    pointer-events:auto;
  }

  body.nav-open{ overflow:hidden; }
}