/* ============================================================
   MAIN.CSS — Global styles for SolarFold website
   ============================================================ */

/* --- CSS VARIABLES --- */
:root {
  --c-dark: #0a1628;
  --c-navy: #1a3a5c;
  --c-gold: #f59e0b;
  --c-gold-light: #fbbf24;
  --c-gold-dark: #d97706;
  --c-white: #ffffff;
  --c-off-white: #f8f6f2;
  --c-gray-50: #f9fafb;
  --c-gray-100: #f3f4f6;
  --c-gray-200: #e5e7eb;
  --c-gray-400: #9ca3af;
  --c-gray-600: #4b5563;
  --c-gray-800: #1f2937;
  --c-text: #1a1a2e;
  --c-text-light: #6b7280;

  --font-serif: 'Noto Serif SC', serif;
  --font-sans: 'Noto Sans SC', sans-serif;
  --font-display: 'Barlow Condensed', sans-serif;

  --header-h: 72px;
  --radius: 8px;
  --radius-lg: 16px;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow-md: 0 8px 24px rgba(0,0,0,0.12);
  --shadow-lg: 0 20px 48px rgba(0,0,0,0.16);
  --transition: 0.3s ease;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-sans);
  color: var(--c-text);
  background: var(--c-white);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
ul { list-style: none; }

/* --- TYPOGRAPHY --- */
h1, h2, h3, h4, h5 {
  font-family: var(--font-serif);
  line-height: 1.3;
  color: var(--c-dark);
}

/* --- CONTAINER --- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* --- SECTION --- */
.section {
  padding: 96px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}
.section-header h2 {
  font-size: clamp(2rem, 4vw, 2.8rem);
  margin-bottom: 16px;
  color: var(--c-dark);
}
.section-header p {
  font-size: 1.05rem;
  color: var(--c-text-light);
  max-width: 560px;
  margin: 0 auto;
}

.section-label {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-gold-dark);
  background: rgba(245,158,11,0.1);
  border: 1px solid rgba(245,158,11,0.3);
  padding: 4px 14px;
  border-radius: 100px;
  margin-bottom: 16px;
}

/* --- BREADCRUMB --- */
.breadcrumb-section {
  background: var(--c-gray-50);
  padding: 16px 0;
  padding-top: calc(72px + 16px);
  border-bottom: 1px solid var(--c-gray-100);
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
}

.breadcrumb a {
  color: var(--c-text-light);
  transition: var(--transition);
}

.breadcrumb a:hover {
  color: var(--c-dark);
}

.breadcrumb .separator {
  color: var(--c-gray-400);
}

.breadcrumb .current {
  color: var(--c-dark);
  font-weight: 500;
}

/* --- BUTTONS --- */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--c-gold);
  color: var(--c-dark);
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 28px;
  border-radius: var(--radius);
  border: 2px solid var(--c-gold);
  transition: var(--transition);
  white-space: nowrap;
}
.btn-primary:hover {
  background: var(--c-gold-dark);
  border-color: var(--c-gold-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(245,158,11,0.35);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  background: transparent;
  color: var(--c-white);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 28px;
  border-radius: var(--radius);
  border: 2px solid rgba(255,255,255,0.5);
  transition: var(--transition);
  white-space: nowrap;
}
.btn-outline:hover {
  border-color: var(--c-white);
  background: rgba(255,255,255,0.1);
}

.btn-outline-dark {
  display: inline-flex;
  align-items: center;
  background: transparent;
  color: var(--c-dark);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 28px;
  border-radius: var(--radius);
  border: 2px solid var(--c-gray-200);
  transition: var(--transition);
}
.btn-outline-dark:hover {
  border-color: var(--c-gold);
  color: var(--c-gold-dark);
}

.btn-white {
  display: inline-flex;
  align-items: center;
  background: var(--c-white);
  color: var(--c-dark);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 13px 28px;
  border-radius: var(--radius);
  border: 2px solid var(--c-white);
  transition: var(--transition);
}
.btn-white:hover {
  background: var(--c-off-white);
  transform: translateY(-2px);
}

.btn-white-outline {
  display: inline-flex;
  align-items: center;
  background: transparent;
  color: var(--c-white);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 13px 28px;
  border-radius: var(--radius);
  border: 2px solid rgba(255,255,255,0.6);
  transition: var(--transition);
}
.btn-white-outline:hover {
  background: rgba(255,255,255,0.15);
  border-color: var(--c-white);
}

.section-cta {
  text-align: center;
  margin-top: 48px;
}

/* ============================================================
   HEADER
   ============================================================ */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 80px;
  z-index: 1000;
  background: var(--c-white);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: background 0.4s ease, box-shadow 0.4s ease;
}
.site-header.scrolled {
  background: rgba(255,255,255,0.98);
  backdrop-filter: blur(12px);
  box-shadow: 0 4px 20px rgba(0,0,0,0.12);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 40px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
}

/* LOGO */
.logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
}
.logo-img {
  height: 90px;
  width: auto;
  max-width: 420px;
  object-fit: contain;
}

/* NAV */
.main-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}
.nav-link {
  font-size: 1rem;
  font-weight: 500;
  color: var(--c-dark);
  padding: 10px 18px;
  border-radius: var(--radius);
  transition: var(--transition);
  position: relative;
}
.nav-link::after {
  content: '';
  position: absolute;
  bottom: 6px; left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 24px; height: 3px;
  background: var(--c-gold);
  border-radius: 2px;
  transition: transform 0.3s ease;
}
.nav-link:hover, .nav-link.active {
  color: var(--c-gold-dark);
}
.nav-link:hover::after, .nav-link.active::after {
  transform: translateX(-50%) scaleX(1);
}

/* LANGUAGE SWITCHER */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: 24px;
  flex-shrink: 0;
}
.lang-btn {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: 6px;
  border: 1px solid var(--c-gray-200);
  background: transparent;
  color: var(--c-dark);
  cursor: pointer;
  transition: var(--transition);
}
.lang-btn:hover {
  border-color: var(--c-gold);
  color: var(--c-gold-dark);
}
.lang-btn.active {
  background: var(--c-gold);
  border-color: var(--c-gold);
  color: var(--c-dark);
}

/* HAMBURGER */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}
.hamburger span {
  display: block;
  width: 24px; height: 2px;
  background: var(--c-white);
  border-radius: 2px;
  transition: var(--transition);
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   PAGE HERO (inner pages)
   ============================================================ */
.page-hero {
  position: relative;
  min-height: 320px;
  display: flex;
  align-items: flex-end;
  padding-bottom: 60px;
  padding-top: calc(var(--header-h) + 40px);
  overflow: hidden;
}
.page-hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.page-hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}
.page-hero .container {
  position: relative;
  z-index: 1;
}
.page-label {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-gold);
  margin-bottom: 12px;
}
.page-hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  color: var(--c-white);
  margin-bottom: 12px;
  font-family: var(--font-serif);
}
.page-desc {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.75);
  max-width: 500px;
}
.page-hero-scroll {
  position: absolute;
  bottom: 24px; left: 50%;
  transform: translateX(-50%);
  text-align: center;
  z-index: 1;
  color: rgba(255,255,255,0.5);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
}
.scroll-arrow {
  font-size: 1.2rem;
  animation: bounce 2s infinite;
}
@keyframes bounce {
  0%,100% { transform: translateY(0); }
  50% { transform: translateY(6px); }
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: var(--c-dark);
  color: rgba(255,255,255,0.7);
  padding: 72px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1.2fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.7;
  margin-top: 16px;
  margin-bottom: 20px;
}
.logo-light .logo-text { color: var(--c-white); }

.social-links {
  display: flex;
  gap: 12px;
}
.social-links a {
  font-size: 0.8rem;
  font-weight: 500;
  color: rgba(255,255,255,0.5);
  background: rgba(255,255,255,0.08);
  padding: 6px 14px;
  border-radius: 100px;
  transition: var(--transition);
}
.social-links a:hover {
  background: var(--c-gold);
  color: var(--c-dark);
}

.footer-col h4 {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--c-white);
  margin-bottom: 20px;
}
.footer-col a, .footer-col p {
  display: block;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.55);
  margin-bottom: 10px;
  transition: color 0.2s;
}
.footer-col a:hover { color: var(--c-gold); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 24px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-bottom p {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.35);
}
.footer-links {
  display: flex;
  gap: 24px;
}
.footer-links a {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.35);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--c-gold); }
.footer-beian {
  text-align: center;
  padding: 12px 0;
  border-top: 1px solid rgba(255,255,255,0.05);
}
.footer-beian a {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.35);
  transition: color 0.2s;
}
.footer-beian a:hover { color: var(--c-gold); }

/* ============================================================
   CTA BAND
   ============================================================ */
.cta-band {
  background: linear-gradient(135deg, var(--c-navy) 0%, var(--c-dark) 100%);
  padding: 80px 0;
  position: relative;
  overflow: hidden;
}
.cta-band::before {
  content: '☀';
  position: absolute;
  right: -40px; top: 50%;
  transform: translateY(-50%);
  font-size: 240px;
  opacity: 0.04;
  pointer-events: none;
}
.cta-band .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
}
.cta-content h2 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  color: var(--c-white);
  margin-bottom: 8px;
}
.cta-content p {
  color: rgba(255,255,255,0.65);
  font-size: 1rem;
}
.cta-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }
}

@media (max-width: 768px) {
  :root { --header-h: 64px; }
  .section { padding: 64px 0; }

  /* Header adjustments */
  .header-inner { padding: 0 20px; }
  .logo-img { height: 68px; }
  .site-header { height: 80px; }

  /* Breadcrumb adjustments */
  .breadcrumb-section { padding-top: calc(80px + 16px); }

  /* Nav mobile */
  .hamburger { display: flex; }
  .hamburger span { background: var(--c-dark); }
  .main-nav {
    position: fixed;
    top: 64px;
    left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(16px);
    flex-direction: column;
    align-items: flex-start;
    padding: 20px 24px 32px;
    gap: 4px;
    transform: translateY(-110%);
    transition: transform 0.35s ease;
    border-bottom: 1px solid var(--c-gray-200);
  }
  .main-nav.open { transform: translateY(0); }
  .nav-link { font-size: 1rem; padding: 12px 0; width: 100%; color: var(--c-dark); }
  .nav-link::after { display: none; }

  /* Language switcher mobile */
  .lang-switcher {
    position: fixed;
    top: 64px;
    right: 24px;
    transform: translateY(-110%);
    transition: transform 0.35s ease;
    z-index: 1001;
    margin-left: 0;
  }
  .lang-switcher.open { transform: translateY(20px); }
  .lang-btn {
    font-size: 0.85rem;
    padding: 8px 14px;
    border-color: var(--c-gray-200);
    color: var(--c-dark);
  }

  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .footer-bottom { flex-direction: column; text-align: center; }

  .cta-band .container { flex-direction: column; text-align: center; }
  .cta-actions { justify-content: center; }

  .section-header h2 { font-size: 1.8rem; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .btn-primary, .btn-outline, .btn-outline-dark, .btn-white, .btn-white-outline {
    padding: 11px 20px;
    font-size: 0.88rem;
  }
}

/* ============================================================
   FLOATING CONTACT SIDEBAR
   ============================================================ */
.float-contact {
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 0;
  filter: drop-shadow(-4px 4px 16px rgba(0,0,0,0.22));
}

.float-btn {
  display: flex;
  align-items: center;
  gap: 0;
  cursor: pointer;
  position: relative;
  text-decoration: none;
  overflow: hidden;
  /* Default: show icon + label */
  width: 120px;
  height: 52px;
  transition: width 0.32s cubic-bezier(0.4,0,0.2,1),
              box-shadow 0.25s ease,
              transform 0.25s ease;
}

/* Rounded corners: top btn, bottom btn, middle */
.float-btn:first-child {
  border-radius: 10px 0 0 0;
}
.float-btn:last-child {
  border-radius: 0 0 0 10px;
}

/* Icon area */
.float-btn-icon {
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  position: relative;
  z-index: 1;
}

/* Label area */
.float-btn-label {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 600;
  white-space: nowrap;
  color: #fff;
  padding-right: 14px;
  opacity: 1;
  transition: opacity 0.2s ease 0.05s;
}

/* Hover: expand slightly and lift */
.float-btn:hover {
  width: 132px;
  transform: translateX(-6px);
  box-shadow: -6px 4px 20px rgba(0,0,0,0.28);
  z-index: 2;
}

/* Divider line between buttons */
.float-btn + .float-btn::before {
  content: '';
  position: absolute;
  top: 0; left: 10px; right: 0;
  height: 1px;
  background: rgba(255,255,255,0.18);
  z-index: 2;
}

/* --- 留言 button --- */
.float-btn.btn-message {
  background: linear-gradient(135deg, #ff7043 0%, #f4511e 100%);
}
.float-btn.btn-message:hover {
  background: linear-gradient(135deg, #ff8a65 0%, #ff7043 100%);
}

/* --- 微信 button --- */
.float-btn.btn-wechat {
  background: linear-gradient(135deg, #2eb82e 0%, #1aa31a 100%);
}
.float-btn.btn-wechat:hover {
  background: linear-gradient(135deg, #3dd63d 0%, #2eb82e 100%);
}

/* --- WhatsApp button --- */
.float-btn.btn-whatsapp {
  background: linear-gradient(135deg, #25d366 0%, #128c7e 100%);
}
.float-btn.btn-whatsapp:hover {
  background: linear-gradient(135deg, #43e285 0%, #25d366 100%);
}

/* WeChat QR Popup */
.wechat-popup {
  position: absolute;
  right: 100%;
  top: 50%;
  transform: translateY(-50%) translateX(8px);
  background: #fff;
  border-radius: 12px;
  padding: 16px;
  box-shadow: -4px 4px 24px rgba(0,0,0,0.22);
  text-align: center;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.25s ease, transform 0.25s ease;
  min-width: 140px;
  z-index: 10;
}
.float-btn.btn-wechat:hover .wechat-popup {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(-50%) translateX(0);
}
.wechat-popup .qr-box {
  width: 108px;
  height: 108px;
  background: var(--c-gray-100);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 8px;
  font-size: 0.65rem;
  color: var(--c-text-light);
  text-align: center;
  padding: 6px;
  line-height: 1.4;
}
.wechat-popup p {
  font-size: 0.75rem;
  color: #1aa31a;
  font-weight: 600;
}

/* Collapse to icon-only on small screens */
@media (max-width: 768px) {
  .float-btn {
    width: 48px;
    height: 48px;
  }
  .float-btn-label {
    display: none;
  }
  .float-btn:hover {
    width: 48px;
    transform: translateX(-4px);
  }
  .float-btn:first-child { border-radius: 8px 0 0 0; }
  .float-btn:last-child  { border-radius: 0 0 0 8px; }
  .float-btn-icon { width: 48px; height: 48px; font-size: 1.3rem; }
}