@import url('https://fonts.googleapis.com/css2?family=Manrope:wght@400;600;700;800&family=Inter:wght@400;500;600;700&family=Fragment+Mono&display=swap');

:root {
  --bg-primary: #0a0a0a;
  --bg-secondary: #111111;
  --bg-tertiary: #1a1a1a;
  --bg-card: #161616;
  --bg-hover: #1e1e1e;
  --text-primary: #f5f5f5;
  --text-secondary: #a3a3a3;
  --text-tertiary: #6b6b6b;
  --accent: #ffffff;
  --border: #262626;
  --border-hover: #404040;
  --success: #4ade80;
  --error: #f87171;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --shadow: 0 1px 3px rgba(0,0,0,0.4);
  --font-heading: 'Manrope', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-mono: 'Fragment Mono', monospace;
  --max-width: 1100px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

a {
  color: var(--text-primary);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--text-secondary);
}

header {
  border-bottom: 1px solid var(--border);
  padding: 20px 0;
}

header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.logo span {
  color: var(--text-tertiary);
  font-weight: 400;
}

nav a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-left: 32px;
  transition: color 0.2s;
}

nav a:hover {
  color: var(--text-primary);
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.hero {
  padding: 80px 0;
  text-align: center;
}

.hero h1 {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 3rem;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 16px;
}

.hero p {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  padding: 40px 0;
}

.tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 32px 28px;
  transition: border-color 0.2s, background 0.2s;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.tool-card:hover {
  border-color: var(--border-hover);
  background: var(--bg-hover);
}

.tool-card h2 {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: -0.01em;
}

.tool-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.tool-card .arrow {
  color: var(--text-tertiary);
  font-size: 0.875rem;
  margin-top: auto;
}

main.page-content {
  padding: 48px 0;
}

.page-header {
  margin-bottom: 32px;
}

.page-header h1 {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 2rem;
  letter-spacing: -0.03em;
  line-height: 1.2;
}

.page-header p {
  color: var(--text-secondary);
  margin-top: 8px;
  font-size: 0.9375rem;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
  transition: color 0.2s;
}

.back-link:hover {
  color: var(--text-primary);
}

textarea {
  width: 100%;
  min-height: 240px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  padding: 16px;
  resize: vertical;
  outline: none;
  transition: border-color 0.2s;
  line-height: 1.7;
}

textarea:focus {
  border-color: var(--border-hover);
}

textarea::placeholder {
  color: var(--text-tertiary);
}

.toolbar {
  display: flex;
  gap: 8px;
  margin: 16px 0;
  flex-wrap: wrap;
}

button {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 600;
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 20px;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}

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

button.primary {
  background: var(--text-primary);
  color: var(--bg-primary);
  border-color: var(--text-primary);
}

button.primary:hover {
  background: var(--text-secondary);
  border-color: var(--text-secondary);
}

.output-area {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
  min-height: 240px;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.7;
  white-space: pre-wrap;
  word-break: break-all;
  overflow: auto;
  color: var(--text-primary);
}

.error-msg {
  background: rgba(248, 113, 113, 0.1);
  border: 1px solid rgba(248, 113, 113, 0.3);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  color: var(--error);
  font-size: 0.8125rem;
  margin-top: 12px;
}

footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  text-align: center;
  color: var(--text-tertiary);
  font-size: 0.75rem;
}

@media (max-width: 640px) {
  .hero h1 {
    font-size: 2.25rem;
  }

  .tools-grid {
    grid-template-columns: 1fr;
  }

  nav a {
    margin-left: 20px;
  }

  .toolbar {
    gap: 6px;
  }

  button {
    padding: 8px 14px;
  }
}