/* ===== CSS Variables ===== */
:root {
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --bg-muted: #f1f5f9;
  --card: #ffffff;
  --card-border: #e2e8f0;
  --text: #1e293b;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --accent-light: #eef2ff;
  --gradient-from: #6366f1;
  --gradient-to: #ec4899;
  --input-bg: #ffffff;
  --input-border: #e2e8f0;
  --input-focus: #6366f1;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
  --radius: 16px;
  --radius-sm: 10px;
}

body[data-mode='dark'] {
  --bg: #0f172a;
  --bg-soft: #1e293b;
  --bg-muted: #334155;
  --card: #1e293b;
  --card-border: #334155;
  --text: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #818cf8;
  --accent-hover: #6366f1;
  --accent-light: rgba(99,102,241,0.15);
  --input-bg: #0f172a;
  --input-border: #334155;
  --input-focus: #818cf8;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.3);
  --shadow-xl: 0 20px 25px -5px 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', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background 0.3s ease, color 0.3s ease;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Gradient Utilities ===== */
.gradient-text {
  background: linear-gradient(135deg, var(--gradient-from), var(--gradient-to));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== Grid Pattern ===== */
.grid-pattern {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(99,102,241,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99,102,241,0.04) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
}

/* ===== Navbar ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--card-border);
  transition: background 0.3s, box-shadow 0.3s, border-color 0.3s;
}

.navbar.scrolled {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
}

body[data-mode='dark'] .navbar.scrolled {
  background: rgba(15,23,42,0.95);
}

.nav-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
}

.logo-icon {
  width: 34px;
  height: 34px;
  background: linear-gradient(135deg, var(--gradient-from), var(--gradient-to));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
}

.logo-text {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
}

.nav-actions { display: flex; align-items: center; gap: 8px; }

.nav-btn {
  width: 38px;
  height: 38px;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  background: var(--card);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
}

.nav-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ===== Hero Section ===== */
.hero-section {
  position: relative;
  overflow: hidden;
  padding: 140px 24px 80px;
  text-align: center;
  background: var(--bg);
}

.hero-glow {
  position: absolute;
  top: -120px;
  right: -80px;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(99,102,241,0.08), transparent 70%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  max-width: 720px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  padding: 6px 18px;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  border-radius: 100px;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 42px;
  font-weight: 800;
  line-height: 1.3;
  color: var(--text);
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

.hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: linear-gradient(135deg, var(--gradient-from), var(--gradient-to));
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  border-radius: 100px;
  text-decoration: none;
  transition: all 0.3s;
  box-shadow: 0 4px 14px rgba(99,102,241,0.3);
}

.hero-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(99,102,241,0.35);
  opacity: 0.92;
}

.hero-cta svg {
  transition: transform 0.3s;
}

.hero-cta:hover svg {
  transform: translateX(4px);
}

/* ===== Features Section ===== */
.features-section {
  padding: 64px 0;
  background: var(--bg-soft);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--gradient-from), var(--gradient-to));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  margin-bottom: 18px;
  transition: transform 0.3s;
}

.feature-card:hover .feature-icon {
  transform: scale(1.08);
}

.feature-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 6px;
}

.feature-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ===== Section Header ===== */
.section-header {
  text-align: center;
  margin-bottom: 40px;
}

.section-badge {
  display: inline-block;
  padding: 6px 18px;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  border-radius: 100px;
  margin-bottom: 16px;
}

.section-title {
  font-size: 30px;
  font-weight: 800;
  color: var(--text);
}

/* ===== Editor Section ===== */
.editor-section {
  padding: 80px 0;
  background: var(--bg);
}

.editor-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.editor-panel {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-md);
  overflow: hidden;
  min-height: 560px;
}

.panel-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  background: var(--bg-soft);
  border-bottom: 1px solid var(--card-border);
}

.panel-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.panel-dot.red { background: #ef4444; }
.panel-dot.yellow { background: #f59e0b; }
.panel-dot.green { background: #22c55e; }

.panel-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-left: 6px;
}

.panel-toolbar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 18px;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--card-border);
}

.toolbar-label {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 500;
}

.toolbar-select {
  padding: 6px 10px;
  border: 1px solid var(--input-border);
  border-radius: 8px;
  background: var(--input-bg);
  color: var(--text);
  font-size: 12px;
  outline: none;
  cursor: pointer;
  transition: border-color 0.2s;
}

.toolbar-select:hover,
.toolbar-select:focus {
  border-color: var(--accent);
}

.toolbar-btn {
  padding: 6px 14px;
  border: 1px solid var(--input-border);
  border-radius: 8px;
  background: var(--input-bg);
  color: var(--text);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.toolbar-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.file-upload-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border: 1px solid var(--input-border);
  border-radius: 8px;
  background: var(--input-bg);
  color: var(--text);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.file-upload-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  background: linear-gradient(135deg, var(--gradient-from), var(--gradient-to));
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  margin-left: auto;
}

.copy-btn:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

.status-text {
  margin-left: auto;
  font-size: 12px;
  color: #22c55e;
  font-weight: 500;
}

/* ===== Font Size Control ===== */
.font-size-ctrl {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--input-border);
  border-radius: 8px;
  overflow: hidden;
}

.font-size-btn {
  width: 28px;
  height: 28px;
  border: none;
  background: var(--input-bg);
  color: var(--text);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.15s;
  line-height: 1;
}

.font-size-btn:hover {
  background: var(--accent);
  color: #fff;
}

.font-size-label {
  width: 28px;
  text-align: center;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  border-left: 1px solid var(--input-border);
  border-right: 1px solid var(--input-border);
  line-height: 28px;
}

/* ===== Textarea & Preview ===== */
textarea {
  width: 100%;
  flex: 1;
  min-height: 460px;
  resize: vertical;
  background: var(--input-bg);
  color: var(--text);
  border: none;
  padding: 18px;
  font-size: 14px;
  line-height: 1.75;
  font-family: 'SF Mono', 'Fira Code', Menlo, Consolas, monospace;
  outline: none;
}

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

.help-text {
  padding: 10px 18px;
  font-size: 12px;
  color: var(--text-muted);
  border-top: 1px solid var(--card-border);
}

/* ===== Preview Mode Toggle ===== */
.preview-mode-toggle {
  display: inline-flex;
  border: 1px solid var(--input-border);
  border-radius: 8px;
  overflow: hidden;
}

.mode-btn {
  width: 32px;
  height: 30px;
  border: none;
  background: var(--input-bg);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
}

.mode-btn + .mode-btn {
  border-left: 1px solid var(--input-border);
}

.mode-btn:hover {
  color: var(--accent);
}

.mode-btn.active {
  background: var(--accent);
  color: #fff;
}

/* ===== Preview Container ===== */
.preview-container {
  flex: 1;
  display: flex;
  justify-content: center;
  overflow: auto;
  background: var(--bg-soft);
  transition: all 0.3s ease;
  position: relative;
}

/* Desktop mode: preview-area fills the container */
.preview-container:not(.phone-mode) .preview-area {
  flex: 1;
  min-height: 460px;
  overflow: auto;
  background: #fff;
  color: #222;
  padding: 24px;
}

/* Phone mode */
.preview-container.phone-mode {
  padding: 32px 16px;
  align-items: flex-start;
  background: var(--bg-muted);
}

.preview-container.phone-mode .preview-area {
  flex: none;
  width: 375px;
  min-height: 600px;
  max-height: 720px;
  border-radius: 40px;
  border: 6px solid #1e293b;
  box-shadow:
    0 0 0 2px #0f172a,
    0 20px 60px rgba(0,0,0,0.18);
  padding: 48px 18px 36px;
  position: relative;
  overflow-y: auto;
  overflow-x: hidden;
  background: #fff;
  color: #222;
}

body[data-mode='dark'] .preview-container.phone-mode .preview-area {
  border-color: #64748b;
  box-shadow:
    0 0 0 2px #475569,
    0 20px 60px rgba(0,0,0,0.5);
}

/* Phone notch (dynamic island style) */
.preview-container.phone-mode .preview-area::before {
  content: '';
  position: absolute;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  width: 90px;
  height: 24px;
  background: #1e293b;
  border-radius: 14px;
  z-index: 10;
}

body[data-mode='dark'] .preview-container.phone-mode .preview-area::before {
  background: #64748b;
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--card-border);
  padding: 32px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.footer-logo .logo-icon {
  width: 30px;
  height: 30px;
  border-radius: 8px;
}

.footer-logo .logo-text {
  font-size: 16px;
}

.footer-copy {
  font-size: 13px;
  color: var(--text-muted);
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--bg-soft); }
::-webkit-scrollbar-thumb { background: var(--text-muted); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 28px;
  }

  .hero-desc {
    font-size: 15px;
  }

  .hero-section {
    padding: 120px 20px 60px;
  }

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

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

  .editor-panel {
    min-height: auto;
  }

  .footer-inner {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }

  .panel-toolbar {
    gap: 6px;
  }

  .copy-btn {
    margin-left: 0;
    width: 100%;
    justify-content: center;
    margin-top: 4px;
  }

  .status-text {
    margin-left: 0;
    width: 100%;
  }
}