💬 Dialog Modal

<div class="modal-overlay">
  <div class="modal-dialog">
    <div class="modal-header">
      <h3 class="modal-title">Welcome!</h3>
      <button class="modal-close">×</button>
    </div>
    <div class="modal-body">
      <p>Thank you for visiting our website. We're glad to have you here.</p>
    </div>
    <div class="modal-footer">
      <button class="modal-btn-secondary">Cancel</button>
      <button class="modal-btn-primary">Continue</button>
    </div>
  </div>
</div>

.modal-overlay {
  position: relative;
  width: 100%;
  min-height: 400px;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  border-radius: 8px;
}
.modal-dialog {
  background: white;
  border-radius: 12px;
  width: 400px;
  max-width: 100%;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: modalFadeIn 0.3s ease;
}
.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid #e0e0e0;
}
.modal-title {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 700;
  color: #1a1a2e;
}
.modal-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  color: #999;
  cursor: pointer;
  padding: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  transition: all 0.2s;
}
.modal-close:hover {
  background: #f5f5f5;
  color: #1a1a2e;
}
.modal-body {
  padding: 1.5rem;
  color: #666;
  line-height: 1.6;
}
.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid #e0e0e0;
}
.modal-btn-secondary {
  padding: 0.6rem 1.25rem;
  background: transparent;
  color: #666;
  border: 1px solid #e0e0e0;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.modal-btn-secondary:hover {
  background: #f5f5f5;
}
.modal-btn-primary {
  padding: 0.6rem 1.25rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
}
.modal-btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}
@keyframes modalFadeIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}

<div class="modal-overlay">
  <div class="modal-icon-dialog">
    <div class="modal-icon-circle">
      <span class="modal-icon-symbol">🎉</span>
    </div>
    <h3 class="modal-icon-title">Congratulations!</h3>
    <p class="modal-icon-text">You've successfully completed the course. Your certificate is ready to download.</p>
    <button class="modal-icon-btn">Download Certificate</button>
  </div>
</div>

.modal-overlay {
  position: relative;
  width: 100%;
  min-height: 400px;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  border-radius: 8px;
}
.modal-icon-dialog {
  background: white;
  border-radius: 16px;
  width: 380px;
  max-width: 100%;
  padding: 2.5rem 2rem;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: modalFadeIn 0.3s ease;
}
.modal-icon-circle {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  box-shadow: 0 8px 24px rgba(102, 126, 234, 0.3);
}
.modal-icon-symbol {
  font-size: 2.5rem;
}
.modal-icon-title {
  margin: 0 0 0.75rem;
  font-size: 1.4rem;
  font-weight: 700;
  color: #1a1a2e;
}
.modal-icon-text {
  margin: 0 0 1.5rem;
  font-size: 0.95rem;
  color: #666;
  line-height: 1.6;
}
.modal-icon-btn {
  width: 100%;
  padding: 0.85rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  font-size: 0.95rem;
}
.modal-icon-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(102, 126, 234, 0.4);
}
@keyframes modalFadeIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}

<div class="modal-overlay-dark">
  <div class="modal-dark">
    <div class="modal-dark-header">
      <h3 class="modal-dark-title">Settings</h3>
      <button class="modal-dark-close">×</button>
    </div>
    <div class="modal-dark-body">
      <p>Customize your preferences and account settings here.</p>
    </div>
    <div class="modal-dark-footer">
      <button class="modal-dark-btn-secondary">Cancel</button>
      <button class="modal-dark-btn-primary">Save Changes</button>
    </div>
  </div>
</div>

.modal-overlay-dark {
  position: relative;
  width: 100%;
  min-height: 400px;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  border-radius: 8px;
}
.modal-dark {
  background: #1a1a2e;
  border-radius: 12px;
  width: 400px;
  max-width: 100%;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
  animation: modalFadeIn 0.3s ease;
}
.modal-dark-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}
.modal-dark-title {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 700;
  color: white;
}
.modal-dark-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  color: #a0a0b0;
  cursor: pointer;
  padding: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  transition: all 0.2s;
}
.modal-dark-close:hover {
  background: rgba(255, 255, 255, 0.1);
  color: white;
}
.modal-dark-body {
  padding: 1.5rem;
  color: #a0a0b0;
  line-height: 1.6;
}
.modal-dark-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.modal-dark-btn-secondary {
  padding: 0.6rem 1.25rem;
  background: transparent;
  color: #a0a0b0;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.modal-dark-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  color: white;
}
.modal-dark-btn-primary {
  padding: 0.6rem 1.25rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
}
.modal-dark-btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}
@keyframes modalFadeIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}