* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.container {
  background: white;
  padding: 40px;
  border-radius: 10px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  max-width: 550px;
  min-width: 300px;
  width: 100%;
}

.nav {
  position: relative;
  width: 0;
  height: 0;
}

.nav a {
  position: absolute;
  top: -20px;
  width: 100px;
  text-decoration: none;
}

h1,
h2,
h3,
h4,
h5 {
  color: #444;
  text-align: center;
}

a {
  color: #667eea;
}

ul {
  list-style-position: inside;
}

img {
  width: 50%;
  border-radius: 8px;
}

.img-sm {
  width: 40%;
}

@media (max-width: 768px) {
  img,
  .img-sm {
    width: 100%;
    margin-bottom: 8px;
  }
  .container {
    padding: 10px;
  }
  .nav a {
    top: -8px;
  }
}

section {
  width: 100%;
  background: #f9f9f9;
  border-radius: 5px;
  padding: 15px 20px;
  margin-bottom: 20px;
}

section h3 {
  text-align: left;
}

.t-center {
  text-align: center;
}

p,
ul,
li {
  color: #555;
}

.form-group {
  margin-bottom: 20px;
}

.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid #ffffff;
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

label {
  display: block;
  margin-bottom: 5px;
  color: #555;
  font-weight: 500;
}

hr {
  border: none;
  border-top: 1px solid #e0e0e0;
  margin-left: 10%;
  margin-right: 10%;
  margin-top: 18px;
  margin-bottom: 18px;
}

input,
textarea {
  width: 100%;
  padding: 12px;
  border: 2px solid #e0e0e0;
  border-radius: 5px;
  font-size: 14px;
  transition: border-color 0.3s;
}

input:focus,
textarea:focus {
  outline: none;
  border-color: #667eea;
}

textarea {
  resize: vertical;
  min-height: 100px;
}

button,
a.button {
  min-width: 122px;
  padding: 12px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s;
  text-decoration: none;
  text-align: center;
}

button:hover,
a.button:hover {
  transform: translateY(-2px);
}

button:disabled,
a.button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.warning-box {
  background-color: #fff3e0;
  border-radius: 8px;
  padding: 15px 20px;
}

.f-col {
  display: flex;
  flex-direction: column;
  flex-wrap: wrap;
}

.f-row {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
}

.f-center {
  align-items: center;
  justify-content: space-around;
}

.w100 {
  width: 100%;
}

.mb {
  margin-bottom: 25px;
}

.smb {
  margin-bottom: 8px;
}

.mt {
  margin-top: 25px;
}

.smt {
  margin-top: 8px;
}

.mr {
  margin-right: 8px;
}

.ml {
  margin-right: 8px;
}