/* ============================================
   CompressIO — 简约实用风格
   基于PALTOOL.CC设计语言
   ============================================ */

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --success: #16a34a;
  --success-bg: #f0fdf4;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
  --shadow-lg: 0 10px 25px rgba(0,0,0,.08);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===== Header ===== */
.site-header {
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
}
.logo:hover { opacity: .85; }
.logo svg { width: 28px; height: 28px; }
.nav-links { display: flex; gap: 24px; list-style: none; }
.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color .2s;
}
.nav-links a:hover { color: var(--primary); }

/* ===== Coffee Button ===== */
.coffee-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  background: linear-gradient(135deg, #ff813f, #ff6b2b);
  color: #fff !important;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  transition: all .2s;
}
.coffee-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(255,107,43,0.3);
}

/* ===== Container ===== */
.container { max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* ===== Main content ===== */
main { flex: 1; padding: 40px 0; }
.page-title {
  text-align: center;
  margin-bottom: 8px;
}
.page-title h1 {
  font-size: 32px;
  font-weight: 800;
  letter-spacing: -.5px;
}
.page-title p {
  color: var(--text-muted);
  font-size: 16px;
  margin-top: 8px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Tool Card ===== */
.tool-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 32px;
  margin-top: 24px;
}

/* ===== Upload Zone ===== */
@keyframes breathe {
  0%, 100% { box-shadow: 0 0 0 0 rgba(37,99,235,0.15); }
  50% { box-shadow: 0 0 24px 6px rgba(37,99,235,0.10); }
}

.upload-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 48px 24px;
  text-align: center;
  cursor: pointer;
  transition: all .3s;
  background: var(--primary-light);
}
.upload-zone:hover,
.upload-zone.dragover {
  border-color: var(--primary);
  background: #dbeafe;
}
.upload-zone.dragover {
  animation: breathe 1.8s ease-in-out infinite;
}
.upload-zone .icon {
  width: 48px;
  height: 48px;
  margin-bottom: 12px;
  opacity: .6;
}
.upload-zone h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}
.upload-zone p {
  color: var(--text-muted);
  font-size: 14px;
}
.upload-zone input[type="file"] { display: none; }

/* ===== Image Info ===== */
.image-info { display: none; margin-top: 24px; }
.image-info.visible { display: block; }
.info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 20px;
}
.info-item {
  background: var(--bg);
  border-radius: 8px;
  padding: 12px 16px;
}
.info-item .label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: .5px;
  font-weight: 600;
}
.info-item .value {
  font-size: 18px;
  font-weight: 700;
  margin-top: 2px;
}
.info-item .value.saved { color: var(--success); }

/* ===== Preview ===== */
.preview-area {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 20px 0;
}
.preview-box {
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border);
}
.preview-box .label {
  background: var(--bg);
  padding: 8px 12px;
  font-size: 13px;
  font-weight: 600;
  border-bottom: 1px solid var(--border);
}
.preview-box img {
  width: 100%;
  display: block;
}

/* ===== Sample Images ===== */
.sample-section {
  text-align: center;
  margin: 20px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.sample-title {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 12px;
}
.sample-grid {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}
.sample-item {
  width: 72px;
  cursor: pointer;
  border-radius: 8px;
  overflow: hidden;
  border: 2px solid transparent;
  transition: all .2s;
  background: var(--bg);
}
.sample-item:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(37,99,235,0.15);
}
.sample-item img {
  width: 100%;
  height: 54px;
  object-fit: cover;
  display: block;
}
.sample-item span {
  font-size: 10px;
  color: var(--text-muted);
  display: block;
  padding: 4px 0;
  line-height: 1;
}

/* ===== Logo ===== */
.logo-img { height: 32px; display: block; }

/* ===== Steps Indicator ===== */
.steps {
  display: flex;
  justify-content: center;
  gap: 0;
  margin-bottom: 28px;
  counter-reset: step;
}
.step {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  background: var(--bg);
  border: 1px solid var(--border);
  position: relative;
}
.step:first-child { border-radius: 8px 0 0 8px; }
.step:last-child { border-radius: 0 8px 8px 0; }
.step + .step { border-left: none; }
.step::before {
  counter-increment: step;
  content: counter(step);
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--border);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
}
.step.active {
  background: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary);
  z-index: 1;
}
.step.active::before {
  background: var(--primary);
  color: #fff;
}
.step.done {
  background: #f0fdf4;
  border-color: var(--success);
  color: var(--success);
}
.step.done::before {
  background: var(--success);
  color: #fff;
  content: '✓';
}

/* ===== Site Stats ===== */
.site-stats {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 24px;
  margin-top: 32px;
  display: flex;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
  font-size: 14px;
  color: var(--text-muted);
}
.site-stats strong {
  color: var(--primary);
  font-size: 16px;
}

/* ===== Controls ===== */
.controls { margin: 20px 0; }
.control-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  margin-bottom: 16px;
}
.control-row label {
  font-size: 14px;
  font-weight: 600;
  min-width: 100px;
}
.target-size-select {
  flex: 1;
  min-width: 180px;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  background: var(--card-bg);
  cursor: pointer;
}
.target-size-select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,.15);
}

/* ===== Quality Slider ===== */
.quality-row { display: none; }
.quality-row.visible { display: flex; }
.quality-row input[type="range"] {
  flex: 1;
  min-width: 150px;
  accent-color: var(--primary);
}
.quality-value { font-weight: 700; min-width: 40px; text-align: center; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 12px 28px;
  border: none;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all .2s;
  text-decoration: none;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
}
.btn-primary:hover { background: var(--primary-hover); }
.btn-primary:disabled {
  opacity: .5;
  cursor: not-allowed;
}
.btn-secondary {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background: var(--border); }
.btn-success {
  background: var(--success);
  color: #fff;
}
.btn-success:hover { opacity: .9; }

/* ===== Progress ===== */
.progress-bar {
  display: none;
  width: 100%;
  height: 6px;
  background: var(--border);
  border-radius: 3px;
  overflow: hidden;
  margin: 16px 0;
}
.progress-bar.visible { display: block; }
.progress-bar .fill {
  height: 100%;
  background: var(--primary);
  border-radius: 3px;
  width: 0%;
  transition: width .3s;
}

/* ===== Result ===== */
.result-area { display: none; margin-top: 16px; }
.result-area.visible { display: block; }
.result-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--success-bg);
  color: var(--success);
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 16px;
}

/* ===== SEO Content ===== */
.seo-content { margin-top: 48px; padding-top: 32px; border-top: 1px solid var(--border); }
.seo-content h2 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
}
.seo-content h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
  margin-top: 20px;
}
.seo-content p {
  color: var(--text-muted);
  margin-bottom: 12px;
  font-size: 15px;
  line-height: 1.7;
}
.seo-content ul {
  padding-left: 20px;
  margin-bottom: 12px;
  color: var(--text-muted);
}
.seo-content li { margin-bottom: 6px; }

/* ===== Features Grid ===== */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin: 32px 0;
}
.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
}
.feature-card .emoji { font-size: 32px; margin-bottom: 8px; }
.feature-card h3 { font-size: 15px; font-weight: 600; margin-bottom: 4px; }
.feature-card p { font-size: 13px; color: var(--text-muted); }

/* ===== Footer ===== */
.site-footer {
  background: var(--card-bg);
  border-top: 1px solid var(--border);
  padding: 24px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
  margin-top: auto;
}

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .container { padding: 0 16px; }
  .page-title h1 { font-size: 24px; }
  .tool-card { padding: 20px; }
  .upload-zone { padding: 32px 16px; }
  .preview-area { grid-template-columns: 1fr; }
  .info-grid { grid-template-columns: 1fr; }
  .site-header .container { flex-direction: column; gap: 12px; }
}

/* ===== FAQ ===== */
.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
}
.faq-item summary {
  font-weight: 600;
  cursor: pointer;
  font-size: 15px;
  padding: 4px 0;
}
.faq-item p {
  color: var(--text-muted);
  font-size: 14px;
  margin-top: 8px;
  padding-left: 4px;
}