:root {
  /* Dark Theme (Default) */
  --bg-color: #15202b;
  --container-bg: #1e2732;
  --text-color: #ffffff;
  --text-muted: #8b98a5;
  --input-bg: #273340;
  --input-border: #38444d;
  --input-focus: #1d9bf0;
  --btn-primary: #1d9bf0;
  --btn-hover: #1a8cd8;
  --stepper-bg: #38444d;
  --stepper-text: #ffffff;
  --stepper-hover: #2c3640;
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
  --border-radius: 16px;
}

body.light-theme {
  /* Light Theme */
  --bg-color: #f7f9f9;
  --container-bg: #ffffff;
  --text-color: #0f1419;
  --text-muted: #536471;
  --input-bg: #eff3f4;
  --input-border: #cfd9de;
  --input-focus: #1d9bf0;
  --btn-primary: #1d9bf0;
  --btn-hover: #1a8cd8;
  --stepper-bg: #eff3f4;
  --stepper-text: #0f1419;
  --stepper-hover: #cfd9de;
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  max-width: 600px;
  margin: 40px auto;
  padding: 30px;
  border-radius: var(--border-radius);
  background: var(--container-bg);
  box-shadow: var(--shadow);
  transition:
    background-color 0.3s,
    color 0.3s,
    box-shadow 0.3s;
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

h1 {
  color: var(--btn-primary);
  margin: 0;
  font-size: 24px;
}

.theme-toggle-btn {
  background: transparent;
  color: var(--text-color);
  border: 1px solid var(--input-border);
  padding: 8px 12px;
  border-radius: 9999px;
  cursor: pointer;
  font-size: 14px;
  width: auto;
  font-weight: bold;
  transition: all 0.2s;
}

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

label {
  display: block;
  margin-top: 15px;
  font-weight: bold;
  color: var(--text-color);
}

input[type="text"],
input[type="number"],
select,
textarea {
  width: 100%;
  padding: 12px;
  margin-top: 5px;
  background-color: var(--input-bg);
  color: var(--text-color);
  border: 1px solid var(--input-border);
  border-radius: 8px;
  box-sizing: border-box;
  font-family: inherit;
  font-size: 15px;
  transition: all 0.2s ease;
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--input-focus);
  box-shadow: 0 0 0 2px rgba(29, 155, 240, 0.2);
  background-color: var(--container-bg);
}

.side-by-side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 15px;
}

.side-by-side label {
  margin-top: 15px;
}

.stepper-group {
  display: flex;
  gap: 8px;
  margin-top: 5px;
}

.stepper-btn {
  width: 50px;
  margin-top: 0;
  font-size: 20px;
  background-color: var(--stepper-bg);
  color: var(--stepper-text);
  border-radius: 8px;
  padding: 0;
}

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

input[type="number"] {
  text-align: center;
  font-size: 18px;
  font-weight: bold;
  -moz-appearance: textfield;
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.checkbox-group,
.radio-group {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 10px;
}

.radio-group {
  grid-template-columns: 1fr 1fr 1fr;
}

.checkbox-group label,
.radio-group label {
  margin-top: 0;
  font-weight: normal;
  cursor: pointer;
}

/* --- Hashtag Section Styles --- */
.hashtag-main-label {
  margin-top: 15px;
  margin-bottom: 10px;
  font-size: 16px;
}

.tags-section {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 15px;
}

.sub-label {
  display: block;
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 13px;
  color: var(--text-muted);
  font-weight: normal;
}

.tags-section .checkbox-group {
  margin-top: 0;
  gap: 8px;
  grid-template-columns: 1fr;
}

.action-buttons,
.output-actions {
  display: flex;
  gap: 10px;
  margin-top: 25px;
}

button {
  background-color: var(--btn-primary);
  color: white;
  border: none;
  padding: 12px 20px;
  border-radius: 9999px;
  cursor: pointer;
  font-size: 15px;
  width: 100%;
  font-weight: bold;
  transition: background-color 0.2s;
}

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

.reset-btn {
  background-color: #f4212e;
}

.reset-btn:hover {
  background-color: #df1b27;
}

.copy-btn {
  background-color: #00ba7c;
  margin-top: 0;
}

.copy-btn:hover {
  background-color: #00a06a;
}

.twitter-btn {
  background-color: var(--btn-primary);
  margin-top: 0;
}

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

textarea {
  height: 140px;
  resize: vertical;
  margin-bottom: 10px;
}

#loading {
  color: var(--btn-primary);
  font-style: italic;
  text-align: center;
  font-weight: bold;
}

hr {
  border: 0;
  height: 1px;
  background: var(--input-border);
  margin: 20px 0;
}