/* ===== Theme Variables ===== */
:root {
  --color-bg: #ffffff;
  --color-bg-soft: #f7f8fa;
  --color-surface: #ffffff;
  --color-surface-hover: #f0f2f5;
  --color-border: #e4e7ed;
  --color-text: #1f2329;
  --color-text-soft: #646a73;
  --color-text-muted: #8f959e;
  --color-primary: #4f7cff;
  --color-primary-hover: #3b66e0;
  --color-primary-soft: #eaf0ff;
  --color-success: #00b42a;
  --color-danger: #f53f3f;
  --color-shadow: rgba(31, 35, 41, 0.08);
  --color-shadow-lg: rgba(31, 35, 41, 0.12);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
  --color-bg: #17171a;
  --color-bg-soft: #1f1f23;
  --color-surface: #232328;
  --color-surface-hover: #2c2c33;
  --color-border: #35353c;
  --color-text: #e6e6e6;
  --color-text-soft: #a8a8ad;
  --color-text-muted: #6f6f76;
  --color-primary: #6b8cff;
  --color-primary-hover: #8aa3ff;
  --color-primary-soft: #2a3354;
  --color-success: #23c343;
  --color-danger: #ff5c5c;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --color-shadow-lg: rgba(0, 0, 0, 0.45);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  transition: background 0.2s, color 0.2s;
}

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

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

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

input,
select,
textarea {
  font-family: inherit;
  font-size: 14px;
  color: var(--color-text);
}

/* ===== Layout ===== */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 16px;
}

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: saturate(180%) blur(12px);
}

.header-inner {
  display: flex;
  align-items: center;
  height: 60px;
  gap: 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text);
  white-space: nowrap;
}
.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  border-radius: 8px;
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 800;
}

.main-nav {
  display: flex;
  gap: 4px;
  flex: 1;
}
.main-nav a {
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  color: var(--color-text-soft);
  font-size: 15px;
  font-weight: 500;
  transition: all 0.15s;
}
.main-nav a:hover {
  background: var(--color-surface-hover);
  color: var(--color-text);
}
.main-nav a.active {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}

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

.icon-btn {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  color: var(--color-text-soft);
  transition: all 0.15s;
}
.icon-btn:hover {
  background: var(--color-surface-hover);
  color: var(--color-text);
}
.icon-btn svg {
  width: 20px;
  height: 20px;
}

/* ===== Language Switcher ===== */
.lang-switch {
  position: relative;
}
.lang-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--color-text);
  background: var(--color-surface);
}
.lang-btn:hover {
  border-color: var(--color-primary);
}
.lang-menu {
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 160px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: 0 8px 24px var(--color-shadow-lg);
  padding: 6px;
  display: none;
  z-index: 200;
  max-height: 320px;
  overflow-y: auto;
}
.lang-switch.open .lang-menu {
  display: block;
}
.lang-menu button {
  width: 100%;
  text-align: left;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--color-text);
}
.lang-menu button:hover {
  background: var(--color-surface-hover);
}
.lang-menu button.active {
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 600;
}

/* ===== Main Content ===== */
.site-main {
  flex: 1;
  padding: 24px 0 48px;
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 8px;
}
.page-desc {
  color: var(--color-text-soft);
  font-size: 15px;
  margin-bottom: 24px;
}

/* ===== Generator Layout ===== */
.generator-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 24px;
  align-items: start;
}
.generator-layout > * {
  min-width: 0;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 2px 8px var(--color-shadow);
  overflow: hidden;
}
.card-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--color-border);
  font-size: 16px;
  font-weight: 600;
}
.card-body {
  padding: 20px;
}

/* ===== Tabs ===== */
.type-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}
.type-tab {
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--color-bg-soft);
  color: var(--color-text-soft);
  font-size: 14px;
  font-weight: 500;
  transition: all 0.15s;
  border: 1px solid transparent;
}
.type-tab:hover {
  background: var(--color-surface-hover);
}
.type-tab.active {
  background: var(--color-primary);
  color: #fff;
}

/* ===== Form ===== */
.form-group {
  margin-bottom: 16px;
}
.form-label {
  display: block;
  font-size: 13px;
  color: var(--color-text-soft);
  margin-bottom: 6px;
  font-weight: 500;
}
.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  transition: border-color 0.15s;
}
.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}
.form-textarea {
  resize: vertical;
  min-height: 80px;
  font-family: var(--font-sans);
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

/* Toggle */
.toggle-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 0;
}
.toggle-row label {
  font-size: 14px;
  color: var(--color-text);
}
.switch {
  position: relative;
  width: 40px;
  height: 22px;
}
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}
.switch-slider {
  position: absolute;
  inset: 0;
  background: var(--color-border);
  border-radius: 999px;
  transition: 0.2s;
  cursor: pointer;
}
.switch-slider::before {
  content: "";
  position: absolute;
  width: 16px;
  height: 16px;
  left: 3px;
  top: 3px;
  background: #fff;
  border-radius: 50%;
  transition: 0.2s;
}
.switch input:checked + .switch-slider {
  background: var(--color-primary);
}
.switch input:checked + .switch-slider::before {
  transform: translateX(18px);
}

/* ===== Preview Panel ===== */
.preview-card {
  position: sticky;
  top: 84px;
}
.preview-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
#qr-preview {
  width: 100%;
  max-width: 280px;
  aspect-ratio: 1;
  background: var(--color-bg-soft);
  border-radius: var(--radius-md);
  display: grid;
  place-items: center;
  overflow: hidden;
}
#qr-preview canvas {
  width: 100% !important;
  height: 100% !important;
}
.qr-placeholder {
  color: var(--color-text-muted);
  font-size: 14px;
}

.action-btns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  width: 100%;
}
.btn {
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  transition: all 0.15s;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}
.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover {
  background: var(--color-primary-hover);
}
.btn-secondary {
  background: var(--color-bg-soft);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn-secondary:hover {
  background: var(--color-surface-hover);
}
.btn-block {
  grid-column: 1 / -1;
}

/* ===== Customization Panel ===== */
.custom-section {
  margin-bottom: 20px;
}
.custom-section:last-child {
  margin-bottom: 0;
}
.custom-title {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}
.custom-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

/* Range slider */
.range-row {
  display: flex;
  align-items: center;
  gap: 10px;
}
.range-row input[type="range"] {
  flex: 1;
  accent-color: var(--color-primary);
}
.range-val {
  min-width: 44px;
  text-align: right;
  font-size: 13px;
  color: var(--color-text-soft);
  font-variant-numeric: tabular-nums;
}

/* Color row */
.color-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.color-row input[type="color"] {
  width: 36px;
  height: 36px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: none;
  cursor: pointer;
  padding: 2px;
}
.color-row .form-input {
  flex: 1;
}

/* Option pills */
.pill-group {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.pill {
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  font-size: 13px;
  color: var(--color-text-soft);
  cursor: pointer;
  transition: all 0.15s;
}
.pill:hover {
  border-color: var(--color-primary);
}
.pill.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}

/* Logo upload */
.upload-area {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s;
}
.upload-area:hover {
  border-color: var(--color-primary);
}
.upload-area p {
  font-size: 13px;
  color: var(--color-text-muted);
}
#logo-preview {
  max-width: 80px;
  max-height: 80px;
  margin: 8px auto;
  border-radius: var(--radius-sm);
}

/* ===== Decoder Page ===== */
.decoder-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  max-width: 720px;
  margin: 0 auto;
}
.decode-result {
  background: var(--color-bg-soft);
  border-radius: var(--radius-md);
  padding: 16px;
  min-height: 60px;
  word-break: break-all;
  font-size: 14px;
  white-space: pre-wrap;
}
.decode-result:empty::before {
  content: attr(data-placeholder);
  color: var(--color-text-muted);
}
#camera-video {
  width: 100%;
  border-radius: var(--radius-md);
  background: #000;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}
.camera-box {
  position: relative;
}
.scan-frame {
  position: absolute;
  inset: 20%;
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-md);
  pointer-events: none;
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
  padding: 24px 0;
  margin-top: 48px;
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  color: var(--color-text-muted);
  font-size: 13px;
}
.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-links a {
  color: var(--color-text-soft);
}
.footer-links a:hover {
  color: var(--color-primary);
}

/* ===== Ads ===== */
.ad-slot {
  display: block;
  width: 100%;
  background: var(--color-bg-soft);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: 12px;
  overflow: hidden;
  position: relative;
  text-align: center;
}
.ad-slot .adsbygoogle {
  display: block !important;
  width: 100% !important;
}
.ad-slot::before {
  content: "Advertisement";
  position: absolute;
  top: 4px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 10px;
  letter-spacing: 0.5px;
  opacity: 0.6;
}
#ad-header-banner {
  width: 100%;
  min-width: 320px;
  min-height: 90px;
  margin: 16px auto;
  max-width: 728px;
}
#ad-footer-banner {
  width: 100%;
  min-width: 320px;
  min-height: 90px;
  max-width: 728px;
  margin: 0 auto 24px;
}

/* ===== About Page ===== */
.about-content {
  max-width: 760px;
  margin: 0 auto;
}
.about-content h2 {
  font-size: 20px;
  margin: 28px 0 12px;
}
.about-content p {
  color: var(--color-text-soft);
  margin-bottom: 12px;
}
.about-content ul {
  padding-left: 20px;
  color: var(--color-text-soft);
}
.about-content li {
  margin-bottom: 6px;
}

/* ===== Responsive ===== */
@media (max-width: 960px) {
  .generator-layout {
    grid-template-columns: 1fr;
  }
  .preview-card {
    position: static;
  }
}

@media (max-width: 640px) {
  .header-inner {
    height: 56px;
    gap: 8px;
  }
  .container {
    padding: 0 12px;
  }
  .logo {
    font-size: 17px;
  }
  .main-nav {
    display: none;
  }
  .header-actions {
    margin-left: auto;
  }
  .site-main {
    padding: 16px 0 32px;
  }
  .page-title {
    font-size: 22px;
  }
  .card-body {
    padding: 16px;
  }
  .form-row,
  .custom-grid {
    grid-template-columns: 1fr;
  }
  .action-btns {
    grid-template-columns: 1fr 1fr;
  }
  #ad-header-banner {
    height: 50px;
  }
  #ad-footer-banner {
    height: 50px;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
}

/* RTL */
[dir="rtl"] .main-nav {
  flex-direction: row-reverse;
}
[dir="rtl"] .lang-menu {
  right: auto;
  left: 0;
}
[dir="rtl"] .range-val {
  text-align: left;
}

/* Utility */
.hidden {
  display: none !important;
}
.mt-16 {
  margin-top: 16px;
}