/* ============================================================
   Design Tokens
   ============================================================ */
:root {
  --bg: #F8F9FC;
  --surface: #FFFFFF;
  --surface-alt: #F1F3F9;
  --primary-gradient: linear-gradient(135deg, #6366F1 0%, #8B5CF6 100%);
  --text-primary: #1E1B4B;
  --text-secondary: #6B7280;
  --border: #E5E7EB;
  --accent: #6366F1;
  --accent-hover: #4F46E5;
  --error: #EF4444;
  --error-bg: #FEF2F2;
  --success: #10B981;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 4px 16px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 24px rgba(0,0,0,0.10);
  --transition: 0.2s ease;
  --navbar-height: 64px;
}

[data-theme="dark"] {
  --bg: #0F0E17;
  --surface: #1A1825;
  --surface-alt: #211F30;
  --text-primary: #FFFFFE;
  --text-secondary: #A7A9BE;
  --border: #2D2B3D;
  --accent: #8B5CF6;
  --accent-hover: #7C3AED;
  --error: #F87171;
  --error-bg: #2D1B1B;
  --shadow: 0 1px 3px rgba(0,0,0,0.3), 0 4px 16px rgba(0,0,0,0.25);
  --shadow-md: 0 4px 24px rgba(0,0,0,0.4);
}

/* ============================================================
   Reset & Base
   ============================================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background var(--transition), color var(--transition);
  min-height: 100vh;
}

h1, h2, h3, h4 { font-family: 'Sora', sans-serif; line-height: 1.25; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

button { font-family: inherit; cursor: pointer; border: none; outline: none; }

img { display: block; max-width: 100%; }

.hidden { display: none !important; }

/* ============================================================
   Layout Utilities
   ============================================================ */
.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

.page-wrapper {
  padding-top: calc(var(--navbar-height) + 40px);
  padding-bottom: 80px;
  min-height: 100vh;
}

/* ============================================================
   Navbar
   ============================================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--navbar-height);
  z-index: 100;
  background: rgba(248, 249, 252, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
}

[data-theme="dark"] .navbar { background: rgba(15, 14, 23, 0.85); }

.navbar-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-primary);
  text-decoration: none;
}
.navbar-logo:hover { text-decoration: none; }

.navbar-logo-icon {
  width: 32px; height: 32px;
  background: var(--primary-gradient);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
}

.navbar-links a {
  padding: 6px 14px;
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition), background var(--transition);
}

.navbar-links a:hover {
  color: var(--text-primary);
  background: var(--surface-alt);
  text-decoration: none;
}

.navbar-links a.active {
  color: var(--accent);
  background: var(--surface-alt);
}

.navbar-right { display: flex; align-items: center; gap: 12px; }

.hamburger-btn {
  display: none;
  background: none;
  border: none;
  padding: 6px;
  border-radius: 6px;
  color: var(--text-primary);
  cursor: pointer;
  transition: background var(--transition);
}
.hamburger-btn:hover { background: var(--surface-alt); }

.mobile-menu {
  display: none;
  flex-direction: column;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 12px 24px;
  top: 64px;
  position: fixed;
  left: 0; right: 0;
  z-index: 99;
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
  padding: 10px 0;
  color: var(--text-secondary);
  font-weight: 500;
  border-bottom: 1px solid var(--border);
}
.mobile-menu a:last-child { border-bottom: none; }
.mobile-menu a:hover { color: var(--accent); text-decoration: none; }

@media (max-width: 768px) {
  .navbar-links { display: none; }
  .hamburger-btn { display: flex; }
}

/* ============================================================
   Theme Toggle
   ============================================================ */
.theme-toggle {
  width: 38px; height: 38px;
  border-radius: 50%;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.theme-toggle:hover { background: var(--border); color: var(--text-primary); }

.theme-toggle .icon-sun { display: none; }
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* ============================================================
   Footer
   ============================================================ */
.footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 48px 24px 32px;
  transition: background var(--transition), border-color var(--transition);
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
}

.footer-brand-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: 'Sora', sans-serif;
  font-weight: 700;
  font-size: 1rem;
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 12px;
  max-width: 280px;
}

.footer-col h4 {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: color var(--transition);
}
.footer-col a:hover { color: var(--accent); text-decoration: none; }

.footer-bottom {
  max-width: 1100px;
  margin: 32px auto 0;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p { color: var(--text-secondary); font-size: 0.85rem; }

@media (max-width: 768px) {
  .footer-inner { grid-template-columns: 1fr 1fr; gap: 32px; }
  .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 480px) {
  .footer-inner { grid-template-columns: 1fr; }
}

/* ============================================================
   Cards & Buttons
   ============================================================ */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: background var(--transition), border-color var(--transition);
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  background: var(--primary-gradient);
  color: #fff;
  font-weight: 600;
  font-size: 1rem;
  transition: opacity var(--transition), transform var(--transition);
  border: none;
  cursor: pointer;
}
.btn-primary:hover:not(:disabled) { opacity: 0.92; transform: translateY(-1px); }
.btn-primary:disabled { opacity: 0.55; cursor: not-allowed; transform: none; }

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  background: var(--surface-alt);
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.9rem;
  border: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
  cursor: pointer;
}
.btn-secondary:hover { background: var(--border); }

/* ============================================================
   Spinner
   ============================================================ */
.spinner {
  width: 20px; height: 20px;
  border: 2.5px solid rgba(255,255,255,0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ============================================================
   Home Page
   ============================================================ */
.home-wrapper {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 24px 80px;
  padding-top: calc(var(--navbar-height) + 48px);
}

.hero { text-align: center; margin-bottom: 48px; }
.hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}
.hero p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

.section-label {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.textarea-wrapper { margin-bottom: 28px; }

.textarea-field {
  width: 100%;
  min-height: 220px;
  padding: 16px;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  background: var(--surface);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  line-height: 1.6;
  resize: vertical;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
  outline: none;
}
.textarea-field:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.word-counter {
  margin-top: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.word-counter.over-limit { color: var(--error); font-weight: 500; }

.mode-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-bottom: 28px;
}
@media (max-width: 640px) { .mode-grid { grid-template-columns: repeat(2, 1fr); } }

.mode-card {
  padding: 16px;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
  gap: 8px;
  text-align: left;
}
.mode-card:hover {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}
.mode-card.selected {
  border-color: var(--accent);
  background: linear-gradient(135deg, rgba(99,102,241,0.08) 0%, rgba(139,92,246,0.08) 100%);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.mode-card-icon {
  width: 36px; height: 36px;
  border-radius: 8px;
  background: var(--primary-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.mode-card-name { font-weight: 600; font-size: 0.9rem; color: var(--text-primary); }
.mode-card-desc { font-size: 0.78rem; color: var(--text-secondary); line-height: 1.4; }

.format-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 28px;
}

.format-card {
  padding: 16px 20px;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
  display: flex;
  align-items: center;
  gap: 14px;
}
.format-card:hover {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}
.format-card.selected {
  border-color: var(--accent);
  background: linear-gradient(135deg, rgba(99,102,241,0.08) 0%, rgba(139,92,246,0.08) 100%);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.format-card-icon {
  width: 40px; height: 40px;
  flex-shrink: 0;
  color: var(--accent);
}
.format-card-name { font-weight: 600; font-size: 0.9rem; }

.slider-section { margin-bottom: 32px; }
.slider-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}
.slider-value { font-weight: 700; color: var(--accent); }

.slider-input {
  width: 100%;
  height: 6px;
  -webkit-appearance: none;
  appearance: none;
  border-radius: 3px;
  background: linear-gradient(to right, var(--accent) 0%, var(--accent) var(--fill, 20%), var(--border) var(--fill, 20%), var(--border) 100%);
  outline: none;
  cursor: pointer;
}
.slider-input::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px; height: 20px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px rgba(99,102,241,0.25);
  cursor: pointer;
  transition: box-shadow var(--transition);
}
.slider-input::-webkit-slider-thumb:hover { box-shadow: 0 0 0 6px rgba(99,102,241,0.2); }

.slider-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 8px;
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.submit-row { margin-bottom: 40px; text-align: center; }
.submit-btn { min-width: 240px; padding: 16px 40px; font-size: 1.05rem; }
@media (max-width: 480px) { .submit-btn { width: 100%; } }

.output-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  margin-top: 8px;
  transition: background var(--transition), border-color var(--transition);
}

.output-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}
.output-header h3 { font-size: 1rem; font-weight: 600; }

.copy-btn {
  width: 36px; height: 36px;
  border-radius: 8px;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}
.copy-btn:hover { background: var(--border); color: var(--text-primary); }

.output-body {
  padding: 20px;
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 0.95rem;
}
.output-body ul {
  padding-left: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.output-body li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
}
.output-body li::before {
  content: '–';
  color: var(--accent);
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 2px;
}
.output-body p { margin-bottom: 12px; }
.output-body p:last-child { margin-bottom: 0; }

.output-meta {
  padding: 10px 20px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-secondary);
  background: var(--surface-alt);
}

.error-card {
  background: var(--error-bg);
  border: 1px solid var(--error);
  border-radius: var(--radius);
  padding: 16px 20px;
  color: var(--error);
  font-size: 0.9rem;
  margin-top: 16px;
}

/* ============================================================
   Generic Page
   ============================================================ */
.generic-page {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 24px 80px;
  padding-top: calc(var(--navbar-height) + 48px);
}
.page-header { margin-bottom: 48px; }
.page-header h1 { font-size: clamp(1.8rem, 4vw, 2.5rem); margin-bottom: 12px; }
.page-header p { color: var(--text-secondary); font-size: 1.05rem; }

.section-block { margin-bottom: 40px; }
.section-block h2 {
  font-size: 1.3rem;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}
.section-block h3 { font-size: 1.05rem; margin-bottom: 10px; margin-top: 20px; }
.section-block p { color: var(--text-secondary); margin-bottom: 14px; line-height: 1.75; }
.section-block ul, .section-block ol {
  padding-left: 20px;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 14px;
}
.section-block li { margin-bottom: 6px; }

/* ============================================================
   About Page
   ============================================================ */
.profile-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin: 32px 0;
}
@media (max-width: 560px) { .profile-grid { grid-template-columns: 1fr; } }

.profile-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 12px;
  transition: background var(--transition), border-color var(--transition);
}
.profile-avatar {
  width: 80px; height: 80px;
  border-radius: 50%;
  background: var(--primary-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
}
.profile-name { font-weight: 700; font-size: 1rem; }
.profile-role { color: var(--text-secondary); font-size: 0.85rem; }
.profile-bio { color: var(--text-secondary); font-size: 0.85rem; text-align: center; line-height: 1.6; }

/* ============================================================
   Blog Page
   ============================================================ */
.blog-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}
@media (max-width: 640px) { .blog-grid { grid-template-columns: 1fr; } }

.blog-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: box-shadow var(--transition), border-color var(--transition), background var(--transition);
}
.blog-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--accent);
}
.blog-card-body {
  padding: 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.blog-tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 20px;
  background: linear-gradient(135deg, rgba(99,102,241,0.12) 0%, rgba(139,92,246,0.12) 100%);
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  width: fit-content;
}
.blog-card-title { font-size: 1rem; font-weight: 700; line-height: 1.4; }
.blog-card-excerpt {
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.6;
  flex: 1;
}
.blog-full-content {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.75;
  border-top: 1px solid var(--border);
  padding-top: 16px;
  margin-top: 4px;
}
.blog-full-content p { margin-bottom: 12px; }
.blog-full-content p:last-child { margin-bottom: 0; }
.blog-read-btn { margin: 0 24px 20px; }

/* ============================================================
   Admin Page
   ============================================================ */
.admin-wrapper {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px 80px;
  padding-top: calc(var(--navbar-height) + 48px);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px;
  margin-top: 32px;
}

.stat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-align: center;
  transition: background var(--transition), border-color var(--transition);
}
.stat-value {
  font-family: 'Sora', sans-serif;
  font-size: 2rem;
  font-weight: 700;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.stat-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 6px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
}

.token-form {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  max-width: 400px;
  margin: 40px auto 0;
  transition: background var(--transition), border-color var(--transition);
}
.token-form h2 { margin-bottom: 20px; font-size: 1.2rem; }

.input-field {
  width: 100%;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border);
  background: var(--bg);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  outline: none;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
  margin-bottom: 16px;
}
.input-field:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(99,102,241,0.15);
}

/* ============================================================
   Contact Page
   ============================================================ */
.contact-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  max-width: 520px;
  transition: background var(--transition), border-color var(--transition);
}
.contact-email {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  background: var(--surface-alt);
  border: 1px solid var(--border);
  font-weight: 600;
  color: var(--accent);
  margin: 16px 0;
  text-decoration: none;
  cursor: pointer;
}