:root {
  --bg-color: #0d1117;
  --panel-bg: #161b22;
  --card-bg: #1c2128;
  --border-color: #30363d;
  --text-primary: #c9d1d9;
  --text-secondary: #8b949e;
  --accent-color: #58a6ff;
  --success-color: #3fb950;
  --error-color: #f85149;
  
  --font-sans: 'Inter', -apple-system, sans-serif;
  --font-mono: 'Fira Code', ui-monospace, SFMono-Regular, monospace;
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-color);
  color: var(--text-primary);
  min-height: 100vh;
}

.code-font { font-family: var(--font-mono); }
.mono { font-family: var(--font-mono); }

/* Layout */
.app-container {
  max-width: 1000px;
  margin: 0 auto;
}

.main-content {
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1rem;
}

.header-left h1 { font-size: 1.5rem; font-weight: 600; margin-top: 0.5rem; }

.back-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color 0.2s;
}
.back-link:hover { color: var(--accent-color); }

.header-right p { color: var(--text-secondary); font-size: 0.875rem; }

.card {
  background-color: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
}

.card h2 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: #fff;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
}

/* Realtime Display */
.current-time-card {
  text-align: center;
  padding: 2.5rem 1.5rem;
  background: linear-gradient(180deg, rgba(28,33,40,1) 0%, rgba(22,27,34,1) 100%);
}

.realtime-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
}

.epoch-value.large-code {
  font-size: 2.5rem;
  font-family: var(--font-mono);
  color: var(--accent-color);
  font-weight: 700;
  letter-spacing: 2px;
}

.epoch-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.realtime-display.small .epoch-value {
  font-size: 1.25rem;
  color: #df8e1d;
}

.mt-1 { margin-top: 1rem; }
.mt-4 { margin-top: 2rem; }

/* Tools */
.split-pane {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

@media (max-width: 768px) {
  .split-pane { grid-template-columns: 1fr; }
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.input-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.field-wrapper {
  display: flex;
  background-color: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  overflow: hidden;
}

.field-wrapper:focus-within { border-color: var(--accent-color); }

.field-wrapper.inline input {
  flex-grow: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  padding: 0.75rem 1rem;
  outline: none;
  font-size: 14px;
}

.primary-btn {
  background-color: #238636;
  color: #fff;
  border: none;
  padding: 0 1.5rem;
  font-family: inherit;
  font-weight: 500;
  cursor: pointer;
  transition: 0.2s;
}
.primary-btn:hover { background-color: #2ea043; }

.results {
  background-color: var(--panel-bg);
  border-radius: 6px;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.result-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px dashed var(--border-color);
  padding-bottom: 0.5rem;
}
.result-row:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.result-row .label { color: var(--text-secondary); font-size: 0.875rem; }
.result-row .value { color: var(--accent-color); font-size: 0.875rem; }

/* Cron */
.cron-wrapper input {
  width: 100%;
  background: transparent;
  border: none;
  color: var(--text-primary);
  padding: 1rem;
  outline: none;
  text-align: center;
  font-size: 1.5rem;
  letter-spacing: 0.5rem;
}

.cron-labels {
  display: flex;
  justify-content: space-around;
  padding: 0 1rem;
}

.cron-labels span {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-align: center;
  flex-grow: 1;
}

.cron-result {
  margin-top: 1.5rem;
  text-align: center;
  min-height: 3rem;
}

.cron-human-text {
  font-size: 1.25rem;
  color: var(--success-color);
  font-weight: 500;
}

.error-text {
  color: var(--error-color);
  font-family: var(--font-mono);
  font-size: 0.875rem;
}