/**
 * CopyBlank - Modern Standalone Production Stylesheet
 * Zero dependencies, pure CSS custom properties, Light & Dark themes
 */

/* ==========================================================================
   CSS CUSTOM PROPERTIES (THEME TOKENS)
   ========================================================================== */
:root {
  /* Light Theme (Default) */
  --bg-page: #F4F9FD;
  --surface-card: #FFFFFF;
  --surface-subtle: #F8FBFE;
  --surface-control: #EDF7FC;
  --surface-control-active: #D9EEFA;
  --surface-control-hover: #D9EEFA;

  --text-main: #17243B;
  --text-secondary: #52647D;
  --text-muted: #8EA2BE;

  --border-main: #DCE7F0;
  --border-subtle: #EDF4F9;
  --border-control: #D9EEFA;

  --primary-blue: #2478D4;
  --primary-hover: #1D67BB;
  --primary-active: #17549C;
  --primary-text: #FFFFFF;

  --preset-text: #2478D4;
  --preset-text-active: #1D67BB;

  --warm-accent: #E4874F;

  --success-text: #16A34A;
  --success-bg: #EAF7EE;
  --success-border: #B8E6C6;

  --shadow-card: 0 8px 30px -4px rgba(36, 120, 212, 0.06);
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.04);

  --radius-card: 18px;
  --radius-control: 12px;
  --radius-pill: 9999px;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

html.dark {
  /* Dark Theme */
  --bg-page: #0F1724;
  --surface-card: #162235;
  --surface-subtle: #131E2E;
  --surface-control: #1B2B40;
  --surface-control-active: #203652;
  --surface-control-hover: #223650;

  --text-main: #F2F7FC;
  --text-secondary: #AFC0D3;
  --text-muted: #8295AA;

  --border-main: #293B52;
  --border-subtle: #203046;
  --border-control: #293B52;

  --primary-blue: #4A9AF0;
  --primary-hover: #3B86D9;
  --primary-active: #2E72BD;
  --primary-text: #FFFFFF;

  --preset-text: #AFC0D3;
  --preset-text-active: #60A5FA;

  --warm-accent: #E4874F;

  --success-text: #4ADE80;
  --success-bg: #132D23;
  --success-border: #1B4D3A;

  --shadow-card: 0 8px 30px -4px rgba(0, 0, 0, 0.3);
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.2);
}

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

html {
  font-family: var(--font-sans);
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  transition: background-color 0.2s ease, color 0.2s ease;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

::selection {
  background-color: var(--surface-control-active);
  color: var(--text-main);
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ==========================================================================
   HEADER
   ========================================================================== */
.site-header {
  height: 64px;
  padding: 0 1rem;
  border-bottom: 1px solid var(--border-main);
  background-color: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

html.dark .site-header {
  background-color: rgba(22, 34, 53, 0.9);
}

.header-container {
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-wrapper {
  display: flex;
  align-items: center;
  gap: 0.625rem;
}

.brand-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background-color: var(--surface-control);
  border: 1px solid var(--border-control);
  display: flex;
  align-items: center;
  justify-content: center;
}

.brand-icon-box {
  width: 16px;
  height: 16px;
  border: 2px dashed var(--primary-blue);
  border-radius: 4px;
}

.brand-title {
  font-size: 1.125rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-main);
}

.brand-badge {
  display: none;
  margin-left: 0.5rem;
  font-size: 0.6875rem;
  font-weight: 500;
  padding: 0.125rem 0.5rem;
  border-radius: var(--radius-pill);
  background-color: var(--surface-control);
  color: var(--primary-blue);
  border: 1px solid var(--border-control);
}

@media (min-width: 640px) {
  .site-header {
    padding: 0 2rem;
  }
  .brand-badge {
    display: inline-block;
  }
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.lang-select-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.lang-icon {
  position: absolute;
  left: 0.625rem;
  pointer-events: none;
  width: 14px;
  height: 14px;
  color: var(--text-secondary);
}

.lang-select {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.375rem 1.5rem 0.375rem 1.75rem;
  border-radius: 8px;
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  color: var(--text-main);
  appearance: none;
  -webkit-appearance: none;
  cursor: pointer;
  transition: border-color 0.15s ease;
}

.lang-select:hover, .lang-select:focus {
  border-color: var(--primary-blue);
  outline: none;
}

.theme-toggle-btn {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.15s ease, color 0.15s ease, background-color 0.15s ease;
}

.theme-toggle-btn:hover {
  border-color: var(--primary-blue);
  color: var(--primary-blue);
}

.theme-toggle-btn svg {
  width: 16px;
  height: 16px;
}

/* ==========================================================================
   LAYOUT
   ========================================================================== */
.main-wrapper {
  flex: 1;
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 1.5rem 1rem 2.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  min-width: 0;
  box-sizing: border-box;
}

@media (min-width: 640px) {
  .main-wrapper {
    padding: 2.5rem 1.5rem 3.5rem;
  }
}

/* ==========================================================================
   HERO
   ========================================================================== */
.hero-section {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.hero-title {
  font-size: 1.625rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  color: var(--text-main);
  line-height: 1.25;
}

@media (min-width: 640px) {
  .hero-title {
    font-size: 2rem;
  }
}

.hero-subtitle {
  margin-top: 0.375rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

@media (min-width: 640px) {
  .hero-subtitle {
    font-size: 1rem;
  }
}

/* Feedback Banner */
.feedback-banner {
  max-width: 440px;
  margin: 0 auto;
  padding: 0.625rem 1rem;
  border-radius: var(--radius-control);
  background-color: var(--success-bg);
  border: 1px solid var(--success-border);
  color: var(--success-text);
  font-size: 0.875rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  box-shadow: var(--shadow-sm);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.feedback-banner.hidden {
  display: none;
}

/* ==========================================================================
   MAIN TOOL CARD
   ========================================================================== */
.tool-card {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.tool-top-grid {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  padding: 1.25rem;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
}

@media (min-width: 640px) {
  .tool-top-grid {
    padding: 2rem;
  }
}

@media (min-width: 1024px) {
  .tool-top-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 2.5rem;
  }
}

.tool-column {
  min-width: 0;
  width: 100%;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1rem;
}

.tool-column-alt {
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
}

@media (min-width: 1024px) {
  .tool-column-alt {
    padding-top: 0;
    border-top: none;
  }
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.625rem;
  border-radius: var(--radius-pill);
  font-size: 0.75rem;
  font-weight: 600;
  background-color: var(--surface-control);
  color: var(--primary-blue);
  border: 1px solid var(--border-control);
  margin-bottom: 0.375rem;
}

.tag-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--warm-accent);
}

.column-heading {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-main);
}

.column-desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
  line-height: 1.4;
}

/* Primary Copy Button */
.btn-primary-copy {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  height: 52px;
  padding: 0 1rem;
  border-radius: var(--radius-control);
  font-size: 1rem;
  font-weight: 600;
  background-color: var(--primary-blue);
  color: var(--primary-text);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.625rem;
  box-shadow: 0 4px 12px rgba(36, 120, 212, 0.2);
  transition: all 0.15s ease;
}

.btn-primary-copy:hover {
  background-color: var(--primary-hover);
  box-shadow: 0 6px 16px rgba(36, 120, 212, 0.25);
}

.btn-primary-copy:active {
  transform: scale(0.99);
}

.btn-primary-copy.copied {
  background-color: var(--success-text);
  box-shadow: 0 4px 12px rgba(22, 163, 74, 0.2);
}

/* Manual Fallback */
.manual-fallback-toggle {
  font-size: 0.75rem;
  color: var(--text-secondary);
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-weight: 500;
  transition: color 0.15s ease;
  margin-top: 0.5rem;
}

.manual-fallback-toggle:hover {
  color: var(--primary-blue);
}

.manual-fallback-box {
  margin-top: 0.625rem;
  padding: 0.75rem;
  border-radius: var(--radius-control);
  background-color: var(--surface-subtle);
  border: 1px solid var(--border-main);
}

.manual-fallback-box.hidden {
  display: none;
}

.manual-fallback-help {
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 0.375rem;
}

.manual-fallback-help kbd {
  padding: 0.125rem 0.25rem;
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
}

.manual-textarea {
  width: 100%;
  padding: 0.625rem;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  border-radius: 8px;
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  color: var(--text-main);
  resize: none;
}

.manual-textarea:focus {
  outline: none;
  border-color: var(--primary-blue);
}

/* Quantity Presets */
.presets-header, .stepper-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.25rem 0.5rem;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.presets-header-title, .stepper-header-title {
  font-weight: 600;
  color: var(--text-main);
}

.presets-grid {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.5rem;
}

@media (min-width: 640px) {
  .presets-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

.preset-btn {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  height: 44px;
  padding: 0 0.25rem;
  border-radius: var(--radius-control);
  font-size: 0.8125rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  background-color: var(--surface-control);
  color: var(--preset-text);
  border: 1px solid var(--border-control);
  transition: all 0.15s ease;
}

.preset-btn:hover {
  background-color: var(--surface-control-hover);
  color: var(--preset-text-active);
  border-color: rgba(36, 120, 212, 0.3);
}

.preset-btn:active {
  transform: scale(0.96);
}

.preset-btn.active {
  background-color: var(--surface-control-active);
  color: var(--primary-blue);
  border-color: var(--primary-blue);
}

.preset-btn.copied {
  background-color: var(--success-bg);
  color: var(--success-text);
  border-color: var(--success-border);
}

/* Custom Stepper */
.stepper-row {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.stepper-capsule {
  flex-shrink: 0;
  height: 44px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-control);
  background-color: var(--surface-control);
  border: 1px solid var(--border-control);
  overflow: hidden;
  box-sizing: border-box;
}

.stepper-btn {
  width: 38px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: all 0.15s ease;
  flex-shrink: 0;
}

.stepper-btn:hover {
  background-color: var(--surface-control-hover);
  color: var(--text-main);
}

.stepper-input {
  width: 48px;
  height: 100%;
  text-align: center;
  font-weight: 700;
  font-size: 0.875rem;
  background: transparent;
  color: var(--text-main);
  border: none;
  border-left: 1px solid var(--border-control);
  border-right: 1px solid var(--border-control);
  box-sizing: border-box;
  appearance: textfield;
  -moz-appearance: textfield;
}

.stepper-input::-webkit-outer-spin-button,
.stepper-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.stepper-input:focus {
  outline: none;
}

.btn-custom-copy {
  flex: 1;
  min-width: 0;
  box-sizing: border-box;
  height: 44px;
  padding: 0 0.875rem;
  border-radius: var(--radius-control);
  font-size: 0.8125rem;
  font-weight: 600;
  background-color: var(--primary-blue);
  color: var(--primary-text);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.375rem;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.btn-custom-copy:hover {
  background-color: var(--primary-hover);
}

.btn-custom-copy:active {
  transform: scale(0.99);
}

.btn-custom-copy.copied {
  background-color: var(--success-text);
}

@media (max-width: 390px) {
  .btn-custom-copy {
    padding: 0 0.5rem;
    font-size: 0.75rem;
    gap: 0.25rem;
  }
}

@media (max-width: 330px) {
  .stepper-row {
    flex-wrap: wrap;
  }
  .stepper-capsule {
    width: 100%;
    justify-content: space-between;
  }
  .stepper-btn {
    width: 44px;
  }
  .stepper-input {
    flex: 1;
  }
  .btn-custom-copy {
    width: 100%;
    flex: none;
  }
}

/* ==========================================================================
   TESTER
   ========================================================================== */
.tester-section {
  border-top: 1px solid var(--border-subtle);
  background-color: var(--surface-subtle);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

@media (min-width: 640px) {
  .tester-section {
    padding: 2rem;
  }
}

.tester-header-row {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

@media (min-width: 640px) {
  .tester-header-row {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

.tester-title-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.tester-title-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--primary-blue);
}

.tester-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.tester-desc {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.btn-tester-clear {
  align-self: flex-start;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.625rem;
  border-radius: 8px;
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  transition: all 0.15s ease;
}

@media (min-width: 640px) {
  .btn-tester-clear {
    align-self: auto;
  }
}

.btn-tester-clear:hover {
  color: #E11D48;
  border-color: #FDA4AF;
}

.tester-input-wrapper {
  position: relative;
}

.tester-textarea {
  width: 100%;
  height: 72px;
  padding: 0.875rem;
  padding-right: 5rem;
  font-size: 0.8125rem;
  font-family: var(--font-mono);
  border-radius: var(--radius-control);
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  color: var(--text-main);
  resize: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

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

.tester-textarea:focus {
  outline: none;
  border-color: var(--primary-blue);
  box-shadow: 0 0 0 3px rgba(36, 120, 212, 0.15);
}

.btn-tester-paste {
  position: absolute;
  right: 0.625rem;
  top: 0.625rem;
  padding: 0.375rem 0.75rem;
  border-radius: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  background-color: var(--surface-control);
  color: var(--primary-blue);
  border: 1px solid var(--border-control);
  display: flex;
  align-items: center;
  gap: 0.375rem;
  transition: all 0.15s ease;
}

.btn-tester-paste:hover {
  background-color: var(--surface-control-hover);
}

.tester-note {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--primary-blue);
}

.tester-result-bar {
  padding-top: 0.5rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.75rem;
}

.tester-count-badge {
  font-weight: 600;
  padding: 0.25rem 0.625rem;
  border-radius: 6px;
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  color: var(--text-secondary);
}

.tester-count-badge.has-count {
  background-color: var(--surface-control-active);
  border-color: transparent;
  color: var(--text-main);
}

.tester-status-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-weight: 600;
  padding: 0.25rem 0.625rem;
  border-radius: 8px;
  background-color: var(--success-bg);
  border: 1px solid var(--success-border);
  color: var(--success-text);
}

.tester-status-badge.empty {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-weight: normal;
}

/* ==========================================================================
   OTHER INVISIBLE CHARACTERS (SECTION 4)
   ========================================================================== */
.alternatives-card {
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

@media (min-width: 640px) {
  .alternatives-card {
    padding: 1.75rem;
  }
}

.alternatives-header-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.alternatives-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--text-main);
}

.alternatives-desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.alternatives-grid {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.75rem;
}

@media (min-width: 768px) {
  .alternatives-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  }
}

.alt-item {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  padding: 1rem;
  border-radius: var(--radius-control);
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 0.75rem;
  transition: all 0.15s ease;
}

.alt-item.recommended {
  background-color: var(--surface-subtle);
  border-color: rgba(36, 120, 212, 0.25);
}

html.dark .alt-item.recommended {
  border-color: rgba(74, 154, 240, 0.3);
}

.alt-top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.alt-name {
  font-weight: 700;
  font-size: 0.875rem;
  color: var(--text-main);
}

.alt-code-badge {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 600;
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
  background-color: var(--surface-control);
  color: var(--primary-blue);
  border: 1px solid var(--border-control);
}

.alt-rec-badge {
  display: inline-block;
  font-size: 0.625rem;
  font-weight: 600;
  padding: 0.125rem 0.375rem;
  border-radius: var(--radius-pill);
  background-color: var(--surface-control-active);
  color: var(--primary-blue);
  margin-top: 0.25rem;
}

.alt-desc {
  font-size: 0.75rem;
  color: var(--text-secondary);
  line-height: 1.4;
  margin-top: 0.25rem;
}

.btn-alt-copy {
  width: 100%;
  height: 38px;
  border-radius: var(--radius-control);
  font-size: 0.8125rem;
  font-weight: 600;
  background-color: var(--surface-control);
  color: var(--primary-blue);
  border: 1px solid var(--border-control);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.375rem;
  transition: all 0.15s ease;
}

.btn-alt-copy:hover {
  background-color: var(--surface-control-hover);
}

.btn-alt-copy.copied {
  background-color: var(--success-bg);
  color: var(--success-text);
  border-color: var(--success-border);
}

/* ==========================================================================
   ARTICLE & EDITORIAL CONTENT
   ========================================================================== */
.article-section {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.article-card {
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  border-radius: var(--radius-card);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
  transition: border-color 0.15s ease;
}

.article-card:hover {
  border-color: rgba(36, 120, 212, 0.35);
}

.article-h2 {
  font-size: 1.1875rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.article-h2::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 1.1em;
  background-color: var(--primary-blue);
  border-radius: 2px;
  flex-shrink: 0;
}

.article-h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-main);
}

.article-card p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.65;
}

.article-card ol,
.article-card ul {
  padding-left: 1.25rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.65;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.article-card strong {
  color: var(--text-main);
}

.article-card code {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  background-color: var(--surface-control);
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
  border: 1px solid var(--border-control);
  color: var(--primary-blue);
}

.article-card kbd {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background-color: var(--surface-control);
  border: 1px solid var(--border-main);
  padding: 0.125rem 0.375rem;
  border-radius: 4px;
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.1);
  color: var(--text-main);
}

.article-subgrid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.875rem;
  margin-top: 0.25rem;
}

@media (min-width: 640px) {
  .article-subgrid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.article-subcard {
  background-color: var(--surface-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-control);
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

/* ==========================================================================
   POPULAR USE CASES & FAQ
   ========================================================================== */
.content-section {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 0.5rem;
}

.section-heading-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--primary-blue);
}

.section-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.use-cases-grid {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.75rem;
}

@media (min-width: 640px) {
  .use-cases-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1024px) {
  .use-cases-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.use-case-card {
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
  padding: 1rem;
  border-radius: var(--radius-control);
  background-color: var(--surface-card);
  border: 1px solid var(--border-main);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  transition: border-color 0.15s ease;
}

.use-case-card:hover {
  border-color: rgba(36, 120, 212, 0.4);
}

.use-case-tag {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--primary-blue);
}

.use-case-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
}

.use-case-desc {
  font-size: 0.75rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* FAQ */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.faq-item {
  border-radius: var(--radius-control);
  border: 1px solid var(--border-main);
  background-color: var(--surface-card);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.faq-question-btn {
  width: 100%;
  padding: 1rem;
  text-align: left;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  transition: background-color 0.15s ease;
}

.faq-question-btn:hover {
  background-color: var(--surface-subtle);
}

.faq-icon-arrow {
  width: 16px;
  height: 16px;
  color: var(--text-secondary);
  transition: transform 0.2s ease;
  flex-shrink: 0;
}

.faq-item.open .faq-icon-arrow {
  transform: rotate(180deg);
  color: var(--primary-blue);
}

.faq-answer-panel {
  display: none;
  padding: 0 1rem 1rem;
  font-size: 0.75rem;
  color: var(--text-secondary);
  line-height: 1.6;
  border-top: 1px solid var(--border-subtle);
  padding-top: 0.75rem;
}

.faq-item.open .faq-answer-panel {
  display: block;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  margin-top: 3rem;
  border-top: 1px solid var(--border-main);
  background-color: var(--surface-card);
  padding: 1.5rem 1rem;
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-secondary);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  font-weight: 500;
  margin-bottom: 0.75rem;
}

.footer-nav a:hover {
  color: var(--primary-blue);
}

/* ==========================================================================
   WHATSAPP LANDING PAGE STYLES
   ========================================================================== */
.whatsapp-tool-card {
  max-width: 680px;
  margin: 0 auto 2.5rem auto;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
}

.whatsapp-card-inner {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1.25rem;
  box-sizing: border-box;
  width: 100%;
}

@media (min-width: 640px) {
  .whatsapp-card-inner {
    padding: 2rem;
  }
}

.whatsapp-badge-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.whatsapp-char-info {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  background-color: var(--surface-control);
  padding: 0.25rem 0.625rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-control);
}

.whatsapp-tool-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0.125rem 0 0 0;
  line-height: 1.3;
}

.whatsapp-tool-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin: 0;
}

.whatsapp-copy-btn {
  height: 56px;
  font-size: 1.0625rem;
  font-weight: 700;
  border-radius: var(--radius-control);
  box-shadow: 0 4px 14px rgba(36, 120, 212, 0.28);
}

.whatsapp-copy-btn:hover {
  box-shadow: 0 6px 20px rgba(36, 120, 212, 0.35);
}

.whatsapp-fallback-wrap {
  margin-top: 0.25rem;
}

.whatsapp-extra-link {
  margin-top: 0.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.875rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  text-align: center;
}

.whatsapp-home-link {
  color: var(--primary-blue);
  font-weight: 600;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.whatsapp-home-link:hover {
  text-decoration: underline;
}

/* Subpage Tool Card Styles (Arabic Landing Pages) */
.subpage-tool-card {
  max-width: 680px;
  margin: 0 auto 2.5rem auto;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.03);
}

.subpage-card-inner {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1.25rem;
  box-sizing: border-box;
  width: 100%;
}

@media (min-width: 640px) {
  .subpage-card-inner {
    padding: 2rem;
  }
}

.subpage-badge-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.subpage-char-info {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  background-color: var(--surface-control);
  padding: 0.25rem 0.625rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-control);
}

.subpage-tool-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0.125rem 0 0 0;
  line-height: 1.3;
}

.subpage-tool-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin: 0;
}

.subpage-alt-box {
  background-color: var(--surface-control);
  border: 1px solid var(--border-control);
  border-radius: var(--radius-control);
  padding: 0.875rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.25rem;
}

.subpage-alt-info {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.subpage-alt-title {
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.subpage-alt-hint {
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.subpage-extra-links {
  margin-top: 0.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.875rem;
  color: var(--text-secondary);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  text-align: center;
}

.subpage-extra-links a {
  color: var(--primary-blue);
  font-weight: 600;
  text-decoration: none;
}

.subpage-extra-links a:hover {
  text-decoration: underline;
}

.alt-inline-box {
  background-color: var(--surface-control);
  border: 1px solid var(--border-control);
  border-radius: var(--radius-card);
  padding: 1.25rem;
  margin: 1.25rem 0;
}

.alt-inline-box .alt-top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 0.625rem;
}

.alt-inline-box .alt-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
  margin: 0;
}

/* ==========================================================================
   RTL (RIGHT-TO-LEFT) SUPPORT
   ========================================================================== */
[dir="rtl"] .brand-badge {
  margin-left: 0;
  margin-right: 0.5rem;
}

[dir="rtl"] .lang-icon {
  left: auto;
  right: 0.625rem;
}

[dir="rtl"] .lang-select {
  padding: 0.375rem 1.75rem 0.375rem 1.5rem;
}

[dir="rtl"] .stepper-capsule {
  direction: ltr;
}

[dir="rtl"] .tester-textarea {
  padding-right: 0.875rem;
  padding-left: 5rem;
}

[dir="rtl"] .btn-tester-paste {
  right: auto;
  left: 0.625rem;
}

[dir="rtl"] .faq-question-btn {
  text-align: right;
}

[dir="rtl"] .article-card ol,
[dir="rtl"] .article-card ul {
  padding-left: 0;
  padding-right: 1.25rem;
}