/* 🌐 Global Styles */
body {
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: linear-gradient(135deg, #e0eafc, #cfdef3);
  color: #333;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* --- Navbar Styles --- */
.navbar {
  width: 100vw;
  min-width: 0;
  background: linear-gradient(90deg, #00b4d8 0%, #007bff 100%);
  color: #fff;
  padding: 0 28px;
  font-size: 1.08rem;
  font-family: 'Segoe UI', 'Roboto', Arial, sans-serif;
  font-weight: 500;
  letter-spacing: 0.5px;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.09);
  border-bottom-left-radius: 18px;
  border-bottom-right-radius: 18px;
  transition: background 0.3s;
}

/* ensure navbar is a positioned container and logo sits left */
.navbar { position: relative; justify-content: flex-start !important; }
.logo { order: 1; margin-right: auto; }

/* Navbar Layout */
.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
    padding: 0 24px;
    height: 64px;
    background: #4f46e5;
    z-index: 1000;
}

.logo {
  display: flex;
  align-items: center;
  height: 56px;
}
.logo img {
  height: 38px;
  width: auto;
  margin-right: 8px;
  
}

/* Logo positioning */
.logo {
    flex: 0 0 auto;
}

/* Nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links li a {
  color: #fff;
  text-decoration: none;
  font-weight: 600;
  font-size: 1.05rem;
  padding: 6px 14px;
  border-radius: 8px;
  transition: background 0.18s, color 0.18s;
  letter-spacing: 0.5px;
}
.nav-links li a:hover,
.nav-links li a:focus {
  background: rgba(255,255,255,0.13);
  color: #ffe066;
}

.auth-button {
  margin-left: 18px;
}
.auth-button a {
  display: inline-block;
  padding: 8px 24px;
  background: #00b4d8;
  color: white;
  border-radius: 24px;
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
}
.auth-button a:hover {
  background: #0096c7;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 180, 216, 0.2);
}

/* Mobile Specific Styles */
@media (max-width: 700px) {
    /* Mobile auth button styling */
    .nav-links .auth-button a {
        width: 100%;
        padding: 8px 24px;
        background: transparent;
        box-shadow: none;
        text-align: left;
    }

    .nav-links .auth-button a:hover {
        background: rgba(255, 255, 255, 0.1);
        transform: none;
        box-shadow: none;
    }

    .navbar {
        padding: 0 16px;
    }

    .logo {
        order: 1;
    }

    .nav-toggle {
        order: 3;
        position: absolute !important;
        right: 16px !important;
        top: 50% !important;
        transform: translateY(-50%) !important;
        margin: 0 !important;
        padding: 8px !important;
        background: transparent !important;
        border: none !important;
        outline: none !important;
        box-shadow: none !important;
        z-index: 1100 !important;
    }

    /* keep nav links hidden by default and full width when open */
    .nav-links {
        order: 2;
        position: absolute;
        top: 64px;
        left: 0;
        width: 100%;
        display: none;
        flex-direction: column;
        padding: 0;
        margin: 0;
        z-index: 1000;
        align-items: flex-start; /* avoid centering items */
    }

    .nav-links.open {
        display: flex;
    }

    .container {
        margin-top: 72px;
        padding: 0 16px;
    }
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  outline: none;
  cursor: pointer;
  margin-left: 18px;
}
.hamburger {
  display: block;
  width: 26px;
  height: 3px;
  background: #fff;
  border-radius: 2px;
  position: relative;
}
.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
  width: 26px;
  height: 3px;
  background: #fff;
  border-radius: 2px;
  transition: 0.2s;
}
.hamburger::before {
  top: -8px;
}
.hamburger::after {
  top: 8px;
}

/* --- Adjust Container for Navbar --- */
body {
  padding-top: 70px; /* Height of navbar + some space */
  box-sizing: border-box;
  min-width: 0;
}

/* Container */
.container {
  margin: 0 auto;
  margin-top: 30px;
  max-width: 1200px;
  width: 100%;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px;
  text-align: center;
  background: #ffffffc7;
  border-radius: 20px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.1);
  backdrop-filter: blur(6px);
  transition: transform 0.3s ease;
}

.container:hover {
  transform: translateY(-3px);
}

h1 {
  margin-bottom: 25px;
  font-size: 2.2rem;
  font-weight: 800;
  color: #1a1a1a;
  letter-spacing: 1px;
  text-transform: uppercase;
  background: linear-gradient(135deg, #007bff, #00b4d8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Upload Section */
.upload-section {
  display: flex;
  gap: 20px;
  margin-bottom: 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.upload-box {
  border: 2.5px dashed #00b4d8;
  padding: 24px 10px 10px 10px;
  text-align: center;
  cursor: pointer;
  position: relative;
  width: 180px;
  min-height: 220px;
  background: linear-gradient(135deg, #f8fdff 60%, #e0f7fa 100%);
  border-radius: 18px;
  box-shadow: 0 4px 18px rgba(0, 180, 216, 0.07);
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s, transform 0.2s;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.upload-box:hover, .upload-box.dragover {
  border-color: #007bff;
  background: linear-gradient(135deg, #e0f7fa 60%, #caf0f8 100%);
}

.upload-icon {
  font-size: 2.8rem;
  color: #00b4d8;
  margin-bottom: 10px;
  transition: color 0.2s;
}

.upload-box:hover .upload-icon,
.upload-box.dragover .upload-icon {
  color: #007bff;
}

.upload-hint {
  color: #0096c7;
  font-size: 1.07rem;
  font-weight: 500;
  margin-bottom: 6px;
  letter-spacing: 0.2px;
  transition: color 0.2s;
}

.upload-box:hover .upload-hint,
.upload-box.dragover .upload-hint {
  color: #0077b6;
}

.preview-img {
  width: 100%;
  height: auto;
  display: none;
  margin-top: 10px;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.09);
  /* background: #fff; */
}

/* Preview Container */
.preview-container {
  margin: 25px 0;
}

.canvas-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-bottom: 20px;
}

#previewArea {
  /* default fixed size you requested */
  width: 531px;
  height: 413px;
  max-width: 100%;
  aspect-ratio: auto; /* let JS set exact visual size when needed */
  position: relative;
  border: 3px solid #f1f1f1;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.15);
  transition: transform 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* keep responsive behavior on small screens */
@media (max-width: 600px) {
  #previewArea { width: 98vw; height: auto; }
}

.checkerboard {
  background-image:
      linear-gradient(45deg, #f0f0f0 25%, transparent 25%),
      linear-gradient(-45deg, #f0f0f0 25%, transparent 25%),
      linear-gradient(45deg, transparent 75%, #f0f0f0 75%),
      linear-gradient(-45deg, transparent 75%, #f0f0f0 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

#mergeCanvas {
  border: 1px solid #ccc;
  /* background: #fff; */
  border-radius: 6px;
}

/* Controls */
.controls {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin-top: 20px;
}

button, select {
  padding: 12px 20px;
  font-size: 15px;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: all 0.25s ease;
  font-weight: 600;
}

/* Buttons */
button {
  background: linear-gradient(135deg, #007bff, #00b4d8);
  color: #fff;
  box-shadow: 0 6px 18px rgba(0, 123, 255, 0.35);
}

button:hover {
  background: linear-gradient(135deg, #0056b3, #0096c7);
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 8px 22px rgba(0, 123, 255, 0.45);
}

button:active {
  transform: translateY(1px) scale(0.98);
}

/* Dropdown */
select {
  border: 1px solid #ccc;
  background: #fff;
  color: #333;
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.06);
}

select:focus {
  outline: none;
  border-color: #007bff;
  box-shadow: 0 0 8px rgba(0, 123, 255, 0.4);
}

/* Main flex container for side-by-side layout */
.merge-main-flex {
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  justify-content: center;
  width: 100%;
  gap: 0;
  margin: 0 auto;
  max-width: 1200px;
  min-height: 600px;
}

/* Upload section on the left */
.upload-section {
  display: flex;
  flex-direction: column;
  gap: 18px;
  min-width: 200px;
  max-width: 220px;
  width: 100%;
  align-items: center;
  justify-content: flex-start;
  background: #f8fdff;
  border-radius: 18px 0 0 18px;
  box-shadow: 0 4px 18px rgba(0, 180, 216, 0.07);
  padding: 24px 10px 24px 10px;
}

/* Preview and controls on the right */
.preview-controls-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  background: #fff;
  border-radius: 0 18px 18px 0;
  box-shadow: 0 4px 18px rgba(0, 180, 216, 0.07);
  padding: 24px 18px 24px 18px;
  min-width: 400px;
  width: 100%;
  max-width: 600px;
}

.bg-controls {
  display: flex;
  gap: 18px;
  align-items: center;
  margin-bottom: 18px;
  margin-top: 8px;
}
.bg-controls label {
  font-size: 1rem;
  color: #0077b6;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 6px;
}
.bg-upload-label {
  gap: 4px;
}
#bgImageBtn {
  background: #e0eafc;
  border: none;
  border-radius: 6px;
  padding: 6px 10px;
  cursor: pointer;
  font-size: 1.1rem;
  color: #0077b6;
  margin-left: 4px;
  transition: background 0.2s, color 0.2s;
}
#bgImageBtn:hover {
  background: #caf0f8;
  color: #0096c7;
}

/* Hide upload icon and hint after image is uploaded */
.upload-box.uploaded .upload-icon,
.upload-box.uploaded .upload-hint {
  display: none;
}
.upload-box .preview-img {
  display: none;
}
.upload-box.uploaded .preview-img {
  display: block;
}

/* Spinner for loading animation */
.preview-loading {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(255,255,255,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2;
  border-radius: 24px;
}
.spinner {
  width: 48px;
  height: 48px;
  border: 5px solid #00b4d8;
  border-top: 5px solid #fff;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Checkerboard preview wrapper — responsive and centered */
#previewArea,
.preview-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  padding: 12px;              /* space around canvas */
  background-color: transparent;
  /* classic checkerboard */
  background-image:
    linear-gradient(45deg, #e6e6e6 25%, transparent 25%),
    linear-gradient(-45deg, #e6e6e6 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #e6e6e6 75%),
    linear-gradient(-45deg, transparent 75%, #e6e6e6 75%);
  background-size: 20px 20px; /* tile size */
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

/* Prevent any CSS from forcing mm sized box */
#previewArea[style],
.preview-wrapper[style] {
  width: auto !important;
  height: auto !important;
  min-width: 0 !important;
  min-height: 0 !important;
}

/* Canvas must use the size set by JS (logical canvas width/height) while remaining responsive */
#mergeCanvas,
#previewArea canvas {
  display: block;
  max-width: 100%;
  width: auto !important;    /* let JS set CSS width when scaling */
  height: auto !important;   /* preserve aspect ratio, no CSS swap */
  background: transparent;    /* keep canvas transparent so checker shows */
  box-shadow: none;
}

/* Desktop/ Mobile specific tweaks if needed */
@media (max-width: 700px) {
  #previewArea { padding: 8px; background-size: 16px 16px; }
}

/* Responsive */
@media (max-width: 768px) {
  .navbar {
    font-size: 1rem;
    padding: 12px 20px;
    height: 52px;
  }

  h1 {
    font-size: 1.7rem;
  }

  .upload-section {
    flex-direction: column;
    align-items: center;
  }

  #previewArea {
    max-width: 98vw;
    min-width: 0;
    border-radius: 16px;
  }

  button, select {
    width: 100%;
    max-width: 300px;
  }
}

@media (max-width: 600px) {
  .navbar {
    font-size: 1rem;
    padding: 12px 10px;
  }
  .navbar-brand {
    font-size: 1.1rem;
  }
  .container {
    padding: 6px;
    margin-top: 18px;
  }
  .upload-section {
    gap: 10px;
  }
  #previewArea {
    max-width: 98vw;
    min-width: 0;
    border-radius: 16px;
  }
  #mergeCanvas {
    width: 100% !important;
    height: 100% !important; /* auto */
    max-width: 98vw;
    min-width: 0;
    border-radius: 12px;
  }
  .upload-box {
    width: 90vw;
    max-width: 365px;
    min-width: 120px;
    min-height: 120px;
    padding: 10px;
  }
  .controls {
    flex-direction: column;
    gap: 12px;
    align-items: stretch;
    width: 100%;
    margin-top: 18px;
  }
  .controls button,
  .controls select {
    width: 100%;
    max-width: 100%;
    min-width: 0;
    box-sizing: border-box;
    font-size: 1.1rem;
    padding: 14px 0;
  }
}

/* Responsive: stack upload above preview below 600px */
@media (max-width: 600px) {
  .merge-main-flex {
    flex-direction: column;
    align-items: stretch;
    max-width: 100vw;
    min-width: 0;
  }
  .upload-section {
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 100vw;
    min-width: 0;
    margin-bottom: 12px;
    border-radius: 18px;
    box-shadow: 0 2px 8px rgba(0, 180, 216, 0.09);
    padding: 12px 2vw;
  }
  .preview-controls-section {
    width: 100%;
    max-width: 100vw;
    min-width: 0;
    border-radius: 18px;
    box-shadow: 0 2px 8px rgba(0, 180, 216, 0.09);
    padding: 12px 2vw;
    margin-top: 0;
  }
}

@media (max-width: 400px) {
  .navbar {
    font-size: 0.9rem;
    padding: 8px 2vw;
  }
  .container {
    padding: 2px;
    margin-top: 10px;
  }
  #previewArea {
    width: 96vw;
    max-width: 380px;
    /* height: 40vw; */
    /* max-height: 180px; */
  }
  .upload-box {
    max-width: 295px;
    min-width: 80px;
    min-height: 80px;
    padding: 4px;
  }
  .controls select{
    font: 1em sans-serif;
    padding: 10px;
  }
}

/* --- Samsung Z Fold (280px width) --- */
@media (max-width: 320px) {
  .navbar {
    font-size: 0.8rem;
    padding: 6px 1vw;
  }
  .container {
    padding: 1px;
    margin-top: 6px;
  }
  #previewArea {
    width: 94vw;
    max-width: 120px;
    height: 38vw;
    max-height: 120px;
  }
  .upload-box {
    max-width: 90px;
    min-width: 60px;
    min-height: 60px;
    padding: 2px;
  }
}

/* --- Responsive Navbar --- */
@media (max-width: 900px) {
  .nav-links {
    gap: 16px;
  }
  .auth-button {
    margin-left: 8px;
  }
}

@media (max-width: 700px) {
  .navbar {
    /* flex-wrap: wrap; */
    height: auto;
    padding: 0 8px;
    border-radius: 0 0 14px 14px;
  }
  .logo img {
    height: 39px;
    margin-right: 4px;
  }
  .nav-links {
    position: absolute;
    top: 56px;
    left: 0;
    width: 100vw;
    background: linear-gradient(90deg, #00b4d8 0%, #007bff 100%);
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 0;
    display: none;
    border-bottom-left-radius: 14px;
    border-bottom-right-radius: 14px;
    box-shadow: 0 6px 18px rgba(0,0,0,0.10);
  }
  .nav-links.open {
    display: flex;
  }
  .nav-links li {
    width: 100%;
  }
  .nav-links li a {
    display: block;
    width: 100%;
    padding: 8px 24px;
    font-size: 1rem;
    border-radius: 0;
  }
  .auth-button {
    margin: 0;
    padding: 8px 0 8px 16px;
  }
  .nav-toggle {
    display: flex;
    justify-content: end;
  }

  /* Hide auth button from navbar */
  .auth-button {
    display: none;
  }

  /* Show auth button in nav-links (toggle menu) */
  .nav-links .auth-button {
    display: block;
    width: 100%;
    margin: 0;
    padding: 12px 24px;
    background: transparent;
  }

  .nav-links .auth-button a {
    display: block;
    width: 100%;
    background: transparent;
    box-shadow: none;
    text-align: left;
    font-size: 1rem;
    padding: 0;
  }

  .nav-links .auth-button a:hover {
    background: transparent;
    color: #ffe066;
    box-shadow: none;
  }

  /* Adjust nav-links to include auth button */
  .nav-links.open {
    display: flex;
    flex-direction: column;
  }
}

/* --- Extra Small Devices (Samsung Z Fold, etc) --- */
@media (max-width: 350px) {
  .navbar {
    font-size: 0.85rem;
    padding: 0 2vw;
    height: 44px;
  }
  .logo img {
    height: 32px;
  }
  .auth-button a {
    padding: 5px 10px;
    font-size: 0.95rem;
  }
}

/* Base Layout */
body {
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Main Content Container */
.container {
    margin-top: 80px; /* navbar height + 16px */
    padding: 0 24px;
    max-width: 1200px;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
    box-sizing: border-box;
}

/* Merge Section Layout */
.merge-main-flex {
    display: flex;
    gap: 24px;
    margin-top: 24px;
}

@media (max-width: 600px) {
    .merge-main-flex {
        flex-direction: column;
        gap: 16px;
    }
}

/* Desktop layout: logo left, nav centered, auth button right */
@media (min-width: 701px) {
  .navbar {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    height: 64px;
  }

  .logo {
    order: 1;
    flex: 0 0 auto;
    margin-right: 0;
  }

  /* center the nav by absolutely positioning it in the navbar */
  .nav-links {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    gap: 24px;
    align-items: center;
    list-style: none;
    margin: 0;
    padding: 0;
    z-index: 100; /* above background */
  }

  /* auth button stays on the right */
  .auth-button {
    order: 3;
    flex: 0 0 auto;
    margin-left: auto;
  }

  /* hide mobile toggle on desktop */
  .nav-toggle {
    display: none !important;
  }
}

button.nav-toggle {
    width: 44px !important;
}



/* 📖 Blog Section Styling */
.blog-section {
  margin: 50px auto;
  padding: 20px;
  max-width: 1000px;
}

.blog-title {
  font-size: 1.8rem;
  font-weight: 700;
  color: #333;
  text-align: center;
  margin: 30px 0 20px;
  font-family: "Poppins", sans-serif;
}

.blog-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.blog-card {
  background: linear-gradient(135deg, #f9f9f9, #ffffff);
  border-radius: 15px;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.08);
  padding: 20px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  font-family: "Poppins", sans-serif;
}

.blog-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 10px 22px rgba(0, 0, 0, 0.15);
}

.blog-card h3 {
  font-size: 1.3rem;
  margin-bottom: 10px;
  color: #007bff;
}

.blog-card p {
  font-size: 1rem;
  line-height: 1.6;
  color: #444;
}

/* Mobile responsive */
@media (max-width: 600px) {
  .blog-title {
    font-size: 1.4rem;
  }
  .blog-card h3 {
    font-size: 1.1rem;
  }
  .blog-card p {
    font-size: 0.95rem;
  }
}