:root {
  --bg-color: #f4f4f9;
  --container-bg: #ffffff;
  --text-color: #333333;
  --ball-bg: #eeeeee;
  --shadow-color: rgba(0,0,0,0.1);
  --btn-bg: #4a90e2;
  --btn-hover: #357abd;
}

body.dark-mode {
  --bg-color: #1a1a1a;
  --container-bg: #2d2d2d;
  --text-color: #f0f0f0;
  --ball-bg: #444444;
  --shadow-color: rgba(0,0,0,0.4);
  --btn-bg: #357abd;
  --btn-hover: #4a90e2;
}

body {
  font-family: 'Arial', sans-serif;
  background-color: var(--bg-color);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 2rem 0;
  margin: 0;
  transition: background-color 0.3s, color 0.3s;
}

.container {
  text-align: center;
  background: var(--container-bg);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 4px 6px var(--shadow-color);
  position: relative;
  transition: background-color 0.3s, box-shadow 0.3s;
  width: 90%;
  max-width: 500px;
  margin-bottom: 2rem;
}

.contact-section h2, .animal-test-section h1 {
  color: var(--text-color);
  margin-bottom: 1.5rem;
}

.animal-test-section p {
  color: var(--text-color);
  margin-bottom: 1.5rem;
  opacity: 0.8;
}

.upload-area {
  border: 2px dashed var(--btn-bg);
  border-radius: 12px;
  padding: 2rem;
  cursor: pointer;
  transition: background-color 0.2s;
  margin-bottom: 1rem;
}

.upload-area:hover {
  background-color: var(--shadow-color);
}

.upload-area p {
  margin: 0;
  font-weight: bold;
}

.label-container {
  display: flex;
  flex-direction: column;
  gap: 15px;
  text-align: left;
}

.result-bar-wrapper {
  width: 100%;
  background-color: var(--ball-bg);
  border-radius: 10px;
  height: 25px;
  position: relative;
  overflow: hidden;
}

.result-bar {
  height: 100%;
  border-radius: 10px;
  transition: width 0.5s ease;
}

.result-text {
  position: absolute;
  width: 100%;
  text-align: center;
  line-height: 25px;
  font-size: 0.9rem;
  font-weight: bold;
  color: var(--text-color);
  z-index: 1;
}

.bar-dog { background-color: #fbc400; }
.bar-cat { background-color: #69c8f2; }

.contact-form {
  text-align: left;
}

.form-group {
  margin-bottom: 1.2rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-color);
  font-size: 0.9rem;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 6px;
  background-color: var(--bg-color);
  color: var(--text-color);
  box-sizing: border-box;
  font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--btn-bg);
}

#submit-btn {
  width: 100%;
  padding: 12px;
  font-size: 1rem;
  background-color: var(--btn-bg);
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background-color 0.2s;
}

#submit-btn:hover {
  background-color: var(--btn-hover);
}

h1 {
  color: var(--text-color);
  margin-bottom: 2rem;
}

.theme-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 5px;
  border-radius: 50%;
  transition: background-color 0.2s;
}

.theme-btn:hover {
  background-color: var(--bg-color);
}

.numbers-container {
  display: flex;
  gap: 15px;
  justify-content: center;
  margin-bottom: 2rem;
}

.ball {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background-color: var(--ball-bg);
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: bold;
  font-size: 1.2rem;
  color: var(--text-color);
  box-shadow: inset -2px -2px 5px rgba(0,0,0,0.2), 2px 2px 5px var(--shadow-color);
  transition: transform 0.3s ease, background-color 0.3s, color 0.3s;
}

.ball:hover {
  transform: scale(1.1);
}

#generate-btn {
  padding: 10px 25px;
  font-size: 1.1rem;
  background-color: var(--btn-bg);
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
}

#generate-btn:hover {
  background-color: var(--btn-hover);
}

#generate-btn:active {
  transform: translateY(2px);
}

/* Ball colors based on number ranges */
.ball-yellow { background-color: #fbc400; color: #fff; } /* 1-10 */
.ball-blue { background-color: #69c8f2; color: #fff; }   /* 11-20 */
.ball-red { background-color: #ff7272; color: #fff; }    /* 21-30 */
.ball-gray { background-color: #aaaaaa; color: #fff; }   /* 31-40 */
.ball-green { background-color: #b0d840; color: #fff; }  /* 41-45 */