/* ========================================
   FOOTER STYLES
   ======================================== */

.main-footer {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
  color: #ffffff;
  padding: 80px 0 0;
  margin-top: 100px;
  position: relative;
  overflow: hidden;
}

.main-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(
      circle at 20% 50%,
      rgba(102, 126, 234, 0.1) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 80% 80%,
      rgba(118, 75, 162, 0.1) 0%,
      transparent 50%
    );
  z-index: 0;
}

.footer-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 40px;
  display: grid;
  grid-template-columns: 2fr 1.5fr 1.5fr 1.5fr;
  gap: 60px;
  position: relative;
  z-index: 1;
}

/* ========================================
   FOOTER COLUMNS
   ======================================== */

.footer-column {
  animation: fadeInUp 0.8s ease forwards;
}

.footer-column h3 {
  font-size: 18px;
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 24px;
  letter-spacing: 1px;
  position: relative;
  padding-bottom: 12px;
  color: #ffffff;
}

.footer-column h3::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 50px;
  height: 3px;
  background: linear-gradient(90deg, #667eea, #764ba2);
  border-radius: 2px;
}

/* ========================================
   COMPANY INFO SECTION
   ======================================== */

.footer-about {
  animation-delay: 0.1s;
}

.footer-logo h2 {
  font-size: 36px;
  font-weight: 800;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 4px;
}
.footer-logo h2::after {
  content: "";
  position: absolute;
  bottom: 5px;
  left: 28%;
  transform: translateX(-50%);
  width: 80px;
  height: 2px;
  background: var(--accent-gradient);
  border-radius: 2px;
}

.footer-subtitle {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  font-weight: 500;
  letter-spacing: 2px;
  margin-bottom: 20px;
}

.footer-description {
  font-size: 15px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 30px;
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  color: rgba(255, 255, 255, 0.9);
  font-size: 14px;
}

.contact-item i {
  color: #667eea;
  font-size: 18px;
  margin-top: 2px;
  min-width: 20px;
}

.contact-item a {
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  transition: color 0.3s ease;
  display: block;
}

.contact-item a:hover {
  color: #667eea;
}

.contact-item div {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* ========================================
   SERVICES SECTION
   ======================================== */

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

.footer-links li {
  margin-bottom: 12px;
  animation: slideInLeft 0.5s ease forwards;
  opacity: 0;
}

.footer-links li:nth-child(1) {
  animation-delay: 0.1s;
}
.footer-links li:nth-child(2) {
  animation-delay: 0.2s;
}
.footer-links li:nth-child(3) {
  animation-delay: 0.3s;
}
.footer-links li:nth-child(4) {
  animation-delay: 0.4s;
}
.footer-links li:nth-child(5) {
  animation-delay: 0.5s;
}
.footer-links li:nth-child(6) {
  animation-delay: 0.6s;
}
.footer-links li:nth-child(7) {
  animation-delay: 0.7s;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.3s ease;
  position: relative;
  padding-left: 0;
}

.footer-links a i {
  color: #667eea;
  font-size: 12px;
  transition: transform 0.3s ease;
}

.footer-links a:hover {
  color: #ffffff;
  padding-left: 8px;
}

.footer-links a:hover i {
  transform: translateX(4px);
}

/* ========================================
   QUICK LINKS SECTION
   ======================================== */

.footer-websites {
  margin-top: 30px;
}

.footer-websites h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 16px;
  color: rgba(255, 255, 255, 0.9);
}

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

.website-links a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.website-links a i {
  color: #e74c3c;
  font-size: 16px;
}

.website-links a:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #667eea;
  transform: translateX(8px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

/* ========================================
   SOCIAL MEDIA SECTION
   ======================================== */

.social-title {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 20px;
  color: rgba(255, 255, 255, 0.9);
}

.social-buttons {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.social-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: 10px;
  text-decoration: none;
  color: #ffffff;
  font-weight: 600;
  font-size: 14px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
  border: 2px solid transparent;
}

.social-btn::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: rgba(255, 255, 255, 0.1);
  transition: left 0.3s ease;
}

.social-btn:hover::before {
  left: 100%;
}

.social-btn i {
  font-size: 18px;
}

/* Social Button Colors */
.social-btn.facebook {
  background: linear-gradient(135deg, #1877f2, #0d5dbf);
  box-shadow: 0 4px 12px rgba(24, 119, 242, 0.3);
}

.social-btn.facebook:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(24, 119, 242, 0.5);
}

.social-btn.zalo {
  background: linear-gradient(135deg, #0068ff, #0052cc);
  box-shadow: 0 4px 12px rgba(0, 104, 255, 0.3);
}

.social-btn.zalo:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0, 104, 255, 0.5);
}

.social-btn.messenger {
  background: linear-gradient(135deg, #00b2ff, #006aff);
  box-shadow: 0 4px 12px rgba(0, 178, 255, 0.3);
}

.social-btn.messenger:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(0, 178, 255, 0.5);
}

.social-btn.hotline {
  background: linear-gradient(135deg, #25d366, #128c7e);
  box-shadow: 0 4px 12px rgba(37, 211, 102, 0.3);
}

.social-btn.hotline:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 20px rgba(37, 211, 102, 0.5);
}

/* ========================================
   FOOTER BOTTOM
   ======================================== */

.footer-bottom {
  margin-top: 60px;
  padding: 30px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(0, 0, 0, 0.2);
}

.footer-bottom-content {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
  margin: 0;
}

.footer-bottom-links {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-bottom-links a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s ease;
}

.footer-bottom-links a:hover {
  color: #667eea;
}

.footer-bottom-links span {
  color: rgba(255, 255, 255, 0.3);
}

/* ========================================
   BACK TO TOP BUTTON
   ======================================== */

.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 50px;
  height: 50px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #ffffff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 1000;
  box-shadow: 0 4px 16px rgba(102, 126, 234, 0.4);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(102, 126, 234, 0.6);
}

.back-to-top:active {
  transform: translateY(-2px);
}

/* ========================================
   ANIMATIONS
   ======================================== */

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */

/* Tablet */
@media (max-width: 1024px) {
  .footer-container {
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
  }

  .footer-about {
    grid-column: 1 / -1;
  }
}

/* Mobile */
@media (max-width: 768px) {
  .main-footer {
    padding: 60px 0 0;
    margin-top: 60px;
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 0 24px;
  }

  .footer-about {
    grid-column: 1;
  }

  .footer-logo h2 {
    font-size: 28px;
  }

  .footer-logo h2::after {
    content: "";
    position: absolute;
    bottom: 5px;
    left: 35%;
    transform: translateX(-50%);
    width: 80px;
    height: 2px;
    background: var(--accent-gradient);
    border-radius: 2px;
  }

  .footer-column h3 {
    font-size: 16px;
  }

  .social-buttons {
    grid-template-columns: 1fr;
  }

  .footer-bottom-content {
    flex-direction: column;
    text-align: center;
    padding: 0 24px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 45px;
    height: 45px;
    font-size: 18px;
  }
}

/* Small Mobile */
@media (max-width: 480px) {
  .main-footer {
    padding: 40px 0 0;
  }

  .footer-container {
    gap: 30px;
    padding: 0 20px;
  }

  .footer-logo h2 {
    font-size: 24px;
  }

  .footer-description {
    font-size: 14px;
  }

  .contact-item {
    font-size: 13px;
  }

  .footer-links a {
    font-size: 13px;
  }

  .social-btn {
    padding: 10px 14px;
    font-size: 13px;
  }

  .footer-bottom {
    padding: 20px 0;
  }

  .footer-bottom p,
  .footer-bottom-links a {
    font-size: 12px;
  }
}

/* ========================================
   PRINT STYLES
   ======================================== */

@media print {
  .back-to-top {
    display: none;
  }

  .social-buttons {
    display: none;
  }
}