/* ==========================================================================
   TeXstudio Official Website - Main Stylesheet
   Version: 1.0.0
   Color system derived from official TeXstudio logo
   ========================================================================== */

/* ---------- 1. Design Tokens ---------- */
:root {
  /* Brand colors (extracted from TeXstudio logo) */
  --color-primary: #2c2e71;
  --color-primary-light: #3f43ef;
  --color-primary-dark: #1a1b3d;
  --color-primary-soft: #eceefb;
  --color-secondary: #5a008c;
  --color-secondary-light: #7c2bb8;
  --color-secondary-soft: #f4e8fb;
  --color-accent: #ffe601;
  --color-accent-soft: #fff9c4;

  /* Neutrals */
  --color-text: #1a1a2e;
  --color-text-muted: #5a5a6e;
  --color-text-light: #8a8a9e;
  --color-bg: #ffffff;
  --color-bg-alt: #f6f7fb;
  --color-bg-dark: #14152e;
  --color-border: #e2e5f1;
  --color-border-strong: #c7ccdf;

  /* Status */
  --color-success: #16a34a;
  --color-info: #2563eb;
  --color-warning: #d97706;

  /* Gradients */
  --gradient-brand: linear-gradient(135deg, #2c2e71 0%, #5a008c 100%);
  --gradient-brand-soft: linear-gradient(135deg, #eceefb 0%, #f4e8fb 100%);
  --gradient-accent: linear-gradient(135deg, #ffe601 0%, #ffb800 100%);

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  --font-mono: "SF Mono", "Fira Code", "Source Code Pro", Menlo, Monaco,
    Consolas, "Courier New", monospace;

  /* Spacing scale */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2.5rem;
  --space-2xl: 4rem;
  --space-3xl: 6rem;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(20, 21, 46, 0.06);
  --shadow-md: 0 4px 14px rgba(20, 21, 46, 0.08);
  --shadow-lg: 0 12px 36px rgba(20, 21, 46, 0.12);
  --shadow-xl: 0 24px 60px rgba(20, 21, 46, 0.16);

  /* Layout */
  --container-max: 1200px;
  --header-height: 72px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---------- 2. Reset & Base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

a:hover {
  color: var(--color-secondary);
}

ul,
ol {
  list-style: none;
}

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

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
}

h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
}

h3 {
  font-size: clamp(1.25rem, 2vw, 1.5rem);
}

p {
  margin-bottom: 1rem;
}

/* ---------- 3. Layout Utilities ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: var(--space-3xl) 0;
}

.section--alt {
  background-color: var(--color-bg-alt);
}

.section--dark {
  background-color: var(--color-bg-dark);
  color: #ffffff;
}

.section--dark h1,
.section--dark h2,
.section--dark h3,
.section--dark h4 {
  color: #ffffff;
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto var(--space-2xl);
}

.section-header .eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-secondary);
  margin-bottom: 0.75rem;
  padding: 0.35rem 0.9rem;
  background: var(--color-secondary-soft);
  border-radius: var(--radius-full);
}

.section-header h2 {
  margin-bottom: 1rem;
}

.section-header p {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

.text-center {
  text-align: center;
}

/* ---------- 4. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  border-radius: var(--radius-md);
  transition: all var(--transition);
  white-space: nowrap;
  cursor: pointer;
  border: 1.5px solid transparent;
}

.btn--primary {
  background: var(--gradient-brand);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(44, 46, 113, 0.3);
}

.btn--primary:hover {
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(44, 46, 113, 0.4);
}

.btn--secondary {
  background-color: var(--color-accent);
  color: var(--color-text);
  font-weight: 700;
}

.btn--secondary:hover {
  background-color: #ffcf00;
  transform: translateY(-2px);
  color: var(--color-text);
}

.btn--ghost {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-border-strong);
}

.btn--ghost:hover {
  background-color: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn--light {
  background-color: #ffffff;
  color: var(--color-primary);
}

.btn--light:hover {
  background-color: var(--color-bg-alt);
  transform: translateY(-2px);
}

.btn--lg {
  padding: 1.05rem 2.2rem;
  font-size: 1.1rem;
}

.btn--block {
  display: flex;
  width: 100%;
}

.btn--icon {
  padding: 0.65rem;
  border-radius: var(--radius-sm);
}

/* ---------- 5. Header / Navigation ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition);
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.nav__brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-text);
}

.nav__brand:hover {
  color: var(--color-primary);
}

.nav__brand img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
}

.nav__brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.nav__brand-text small {
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
}

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

.nav__link {
  padding: 0.55rem 1rem;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.nav__link:hover {
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
}

.nav__link.active {
  color: var(--color-primary);
  font-weight: 600;
}

.nav__cta {
  margin-left: 0.75rem;
}

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
}

.nav__toggle span {
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition);
}

.nav__toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

.nav__toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav__toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* ---------- 6. Hero Section ---------- */
.hero {
  position: relative;
  padding: var(--space-3xl) 0 var(--space-2xl);
  background: var(--gradient-brand);
  color: #ffffff;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(
    circle,
    rgba(255, 230, 1, 0.15) 0%,
    transparent 70%
  );
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(
    circle,
    rgba(124, 43, 184, 0.4) 0%,
    transparent 70%
  );
  pointer-events: none;
}

.hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: var(--space-2xl);
  align-items: center;
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  font-size: 0.85rem;
  font-weight: 500;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  margin-bottom: 1.5rem;
}

.hero__eyebrow .dot {
  width: 8px;
  height: 8px;
  background: var(--color-accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.6;
    transform: scale(1.3);
  }
}

.hero h1 {
  color: #ffffff;
  margin-bottom: 1.25rem;
}

.hero h1 .highlight {
  color: var(--color-accent);
}

.hero__lead {
  font-size: 1.15rem;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 2rem;
  max-width: 540px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.15);
}

.hero__stat-num {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
}

.hero__stat-label {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  margin-top: 0.35rem;
}

.hero__visual {
  position: relative;
}

.hero__mockup {
  background: #1a1b3d;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.hero__mockup-bar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: #14152e;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.hero__mockup-bar span {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #4a4b6a;
}

.hero__mockup-bar span:nth-child(1) {
  background: #ff5f57;
}
.hero__mockup-bar span:nth-child(2) {
  background: #febc2e;
}
.hero__mockup-bar span:nth-child(3) {
  background: #28c840;
}

.hero__mockup-title {
  margin-left: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.5);
}

.hero__mockup-body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: 320px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.7;
}

.hero__code {
  padding: 1.25rem;
  color: #c9c9e3;
  background: #1a1b3d;
  overflow: hidden;
}

.hero__code .kw {
  color: #ffe601;
}
.hero__code .cmd {
  color: #7c9cff;
}
.hero__code .str {
  color: #98e88a;
}
.hero__code .cmt {
  color: #6a6b8a;
  font-style: italic;
}
.hero__code .math {
  color: #ff9cf0;
}

.hero__preview {
  padding: 1.25rem;
  background: #ffffff;
  color: var(--color-text);
  font-family: "Times New Roman", Georgia, serif;
}

.hero__preview h4 {
  font-size: 0.95rem;
  text-align: center;
  margin-bottom: 0.75rem;
}

.hero__preview .formula {
  text-align: center;
  font-style: italic;
  margin: 0.75rem 0;
  font-size: 1rem;
}

.hero__preview p {
  font-size: 0.78rem;
  line-height: 1.6;
  margin-bottom: 0.5rem;
  text-align: justify;
}

/* ---------- 7. Trust Bar ---------- */
.trust-bar {
  padding: 2rem 0;
  background: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border);
}

.trust-bar__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-around;
  gap: 2rem;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--color-text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.trust-item svg {
  width: 22px;
  height: 22px;
  color: var(--color-primary);
  flex-shrink: 0;
}

/* ---------- 8. Features Grid ---------- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.feature-card {
  padding: 2rem 1.75rem;
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.feature-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.feature-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  background: var(--gradient-brand-soft);
  color: var(--color-primary);
  margin-bottom: 1.25rem;
}

.feature-card__icon svg {
  width: 28px;
  height: 28px;
}

.feature-card h3 {
  margin-bottom: 0.6rem;
  font-size: 1.2rem;
}

.feature-card p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: 0;
}

/* ---------- 9. Use Cases / Scenarios ---------- */
.scenarios {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.scenario-card {
  position: relative;
  display: flex;
  gap: 1.25rem;
  padding: 1.75rem;
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
  overflow: hidden;
}

.scenario-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-brand);
  opacity: 0;
  transition: opacity var(--transition);
}

.scenario-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
}

.scenario-card:hover::before {
  opacity: 1;
}

.scenario-card__icon {
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
}

.scenario-card__icon svg {
  width: 26px;
  height: 26px;
}

.scenario-card__body h3 {
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
}

.scenario-card__body p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: 0;
}

/* ---------- 10. Testimonials ---------- */
.testimonials {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.testimonial {
  padding: 2rem 1.75rem;
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  transition: all var(--transition);
}

.testimonial:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
}

.testimonial__rating {
  display: flex;
  gap: 2px;
  margin-bottom: 1rem;
  color: var(--color-accent);
}

.testimonial__rating svg {
  width: 18px;
  height: 18px;
}

.testimonial__quote {
  flex-grow: 1;
  font-size: 0.98rem;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 1.5rem;
  position: relative;
  padding-left: 1.5rem;
}

.testimonial__quote::before {
  content: "\201C";
  position: absolute;
  left: -0.15rem;
  top: -1rem;
  font-size: 3.5rem;
  font-family: Georgia, serif;
  color: var(--color-primary-soft);
  line-height: 1;
}

.testimonial__author {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding-top: 1rem;
  border-top: 1px solid var(--color-border);
}

.testimonial__avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 1rem;
  flex-shrink: 0;
}

.testimonial__name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--color-text);
}

.testimonial__role {
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

/* ---------- 11. Stats Section ---------- */
.stats-band {
  background: var(--gradient-brand);
  color: #ffffff;
  padding: var(--space-2xl) 0;
}

.stats-band__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  text-align: center;
}

.stats-band__num {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 0.5rem;
}

.stats-band__label {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.82);
}

/* ---------- 12. CTA Section ---------- */
.cta-section {
  padding: var(--space-2xl) 0;
  background: var(--color-bg-alt);
}

.cta-box {
  position: relative;
  padding: var(--space-2xl) 2.5rem;
  background: var(--gradient-brand);
  border-radius: var(--radius-xl);
  text-align: center;
  color: #ffffff;
  overflow: hidden;
}

.cta-box::before,
.cta-box::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
}

.cta-box::before {
  top: -100px;
  right: -50px;
  width: 280px;
  height: 280px;
  background: radial-gradient(
    circle,
    rgba(255, 230, 1, 0.18) 0%,
    transparent 70%
  );
}

.cta-box::after {
  bottom: -120px;
  left: -60px;
  width: 320px;
  height: 320px;
  background: radial-gradient(
    circle,
    rgba(124, 43, 184, 0.4) 0%,
    transparent 70%
  );
}

.cta-box > * {
  position: relative;
  z-index: 1;
}

.cta-box h2 {
  color: #ffffff;
  margin-bottom: 1rem;
}

.cta-box p {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.88);
  max-width: 600px;
  margin: 0 auto 2rem;
}

.cta-box__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

/* ---------- 13. Page Header (inner pages) ---------- */
.page-header {
  position: relative;
  padding: var(--space-2xl) 0;
  background: var(--gradient-brand);
  color: #ffffff;
  overflow: hidden;
}

.page-header::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(
    circle,
    rgba(255, 230, 1, 0.12) 0%,
    transparent 70%
  );
}

.page-header__inner {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
}

.page-header h1 {
  color: #ffffff;
  margin-bottom: 1rem;
}

.page-header p {
  font-size: 1.15rem;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 0;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 1rem;
}

.breadcrumb a {
  color: rgba(255, 255, 255, 0.85);
}

.breadcrumb a:hover {
  color: var(--color-accent);
}

/* ---------- 14. Download Page ---------- */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.platform-card {
  padding: 2rem 1.75rem;
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: all var(--transition);
}

.platform-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.platform-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: var(--gradient-brand-soft);
  color: var(--color-primary);
  margin-bottom: 1.25rem;
}

.platform-card__icon svg {
  width: 36px;
  height: 36px;
}

.platform-card h3 {
  font-size: 1.3rem;
  margin-bottom: 0.4rem;
}

.platform-card__version {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  margin-bottom: 1.25rem;
}

.platform-card__meta {
  list-style: none;
  margin: 1.25rem 0;
  padding: 1.25rem 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  text-align: left;
}

.platform-card__meta li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.88rem;
  color: var(--color-text-muted);
  padding: 0.25rem 0;
}

.platform-card__meta svg {
  width: 16px;
  height: 16px;
  color: var(--color-success);
  flex-shrink: 0;
}

.install-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  counter-reset: step;
}

.install-step {
  position: relative;
  padding: 1.75rem;
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

.install-step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  top: -18px;
  left: 1.75rem;
  width: 36px;
  height: 36px;
  background: var(--gradient-brand);
  color: #ffffff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.install-step h4 {
  margin: 0.5rem 0 0.5rem;
  font-size: 1.05rem;
}

.install-step p {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

.faq-list {
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 1rem;
  overflow: hidden;
}

.faq-item__question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--color-text);
  text-align: left;
  transition: background var(--transition);
}

.faq-item__question:hover {
  background: var(--color-bg-alt);
}

.faq-item__question .icon {
  width: 22px;
  height: 22px;
  color: var(--color-primary);
  transition: transform var(--transition);
  flex-shrink: 0;
}

.faq-item.open .faq-item__question .icon {
  transform: rotate(45deg);
}

.faq-item__answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition);
}

.faq-item__answer-inner {
  padding: 0 1.5rem 1.25rem;
  color: var(--color-text-muted);
  font-size: 0.96rem;
  line-height: 1.7;
}

.faq-item.open .faq-item__answer {
  max-height: 400px;
}

/* ---------- 15. Docs Page ---------- */
.docs-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 2.5rem;
  align-items: start;
}

.docs-sidebar {
  position: sticky;
  top: calc(var(--header-height) + 1.5rem);
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.25rem;
}

.docs-sidebar h4 {
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-light);
  margin: 1.25rem 0 0.65rem;
  padding-left: 0.75rem;
}

.docs-sidebar h4:first-child {
  margin-top: 0;
}

.docs-sidebar a {
  display: block;
  padding: 0.5rem 0.75rem;
  font-size: 0.92rem;
  color: var(--color-text-muted);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.docs-sidebar a:hover,
.docs-sidebar a.active {
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 500;
}

.docs-content h2 {
  margin: 2.5rem 0 1rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--color-border);
}

.docs-content h2:first-child {
  margin-top: 0;
}

.docs-content h3 {
  margin: 1.75rem 0 0.75rem;
}

.docs-content p {
  margin-bottom: 1rem;
  color: var(--color-text);
}

.docs-content ul,
.docs-content ol {
  margin: 0 0 1.25rem 1.25rem;
  padding-left: 1rem;
}

.docs-content li {
  margin-bottom: 0.4rem;
  list-style: disc;
  color: var(--color-text);
}

.docs-content ol li {
  list-style: decimal;
}

.docs-content code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  padding: 0.15em 0.4em;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border-radius: 4px;
}

.docs-content pre {
  font-family: var(--font-mono);
  background: var(--color-bg-dark);
  color: #e2e5f1;
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: 0 0 1.25rem;
  font-size: 0.88rem;
  line-height: 1.65;
}

.docs-content pre code {
  background: none;
  color: inherit;
  padding: 0;
}

.docs-content blockquote {
  margin: 1.25rem 0;
  padding: 1rem 1.25rem;
  background: var(--color-accent-soft);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-sm);
  color: var(--color-text);
}

.docs-content blockquote p:last-child {
  margin-bottom: 0;
}

.docs-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.94rem;
}

.docs-content th,
.docs-content td {
  text-align: left;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
}

.docs-content th {
  background: var(--color-bg-alt);
  font-weight: 600;
}

/* ---------- 16. About Page ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.about-text h2 {
  margin-bottom: 1rem;
}

.about-text p {
  color: var(--color-text-muted);
  margin-bottom: 1rem;
}

.about-visual {
  padding: 2rem;
  background: var(--gradient-brand-soft);
  border-radius: var(--radius-xl);
  text-align: center;
}

.about-visual img {
  width: 140px;
  height: 140px;
  margin: 0 auto 1.25rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.timeline {
  max-width: 760px;
  margin: 0 auto;
  position: relative;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--color-border);
}

.timeline-item {
  position: relative;
  padding: 0 0 2rem 2.5rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--gradient-brand);
  border: 3px solid #ffffff;
  box-shadow: 0 0 0 2px var(--color-primary);
}

.timeline-item__year {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-secondary);
  margin-bottom: 0.25rem;
}

.timeline-item h4 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.timeline-item p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: 0;
}

.value-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.value-card {
  padding: 1.75rem;
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  text-align: center;
}

.value-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #ffffff;
  margin-bottom: 1rem;
}

.value-card__icon svg {
  width: 28px;
  height: 28px;
}

.value-card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.value-card p {
  font-size: 0.93rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

.community-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.community-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 1.75rem 1.25rem;
  background: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
  color: var(--color-text);
}

.community-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
  color: var(--color-primary);
}

.community-card svg {
  width: 32px;
  height: 32px;
  color: var(--color-primary);
  margin-bottom: 0.75rem;
}

.community-card h4 {
  font-size: 1rem;
  margin-bottom: 0.25rem;
}

.community-card p {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

/* ---------- 17. Download Modal ---------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(20, 21, 46, 0.6);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition), visibility var(--transition);
  padding: 1.5rem;
}

.modal-overlay.open {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: #ffffff;
  border-radius: var(--radius-xl);
  max-width: 560px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  transform: scale(0.92) translateY(20px);
  transition: transform var(--transition);
}

.modal-overlay.open .modal {
  transform: scale(1) translateY(0);
}

.modal__header {
  position: relative;
  padding: 1.75rem 2rem 1.25rem;
  text-align: center;
  background: var(--gradient-brand);
  color: #ffffff;
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.modal__header h3 {
  color: #ffffff;
  font-size: 1.4rem;
  margin-bottom: 0.35rem;
}

.modal__header p {
  color: rgba(255, 255, 255, 0.82);
  font-size: 0.92rem;
  margin: 0;
}

.modal__close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition);
}

.modal__close:hover {
  background: rgba(255, 255, 255, 0.3);
}

.modal__close svg {
  width: 18px;
  height: 18px;
}

.modal__body {
  padding: 1.75rem 2rem 2rem;
}

.qr-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.qr-item {
  text-align: center;
  padding: 1.25rem 0.75rem;
  background: var(--color-bg-alt);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
}

.qr-item__img {
  width: 150px;
  height: 150px;
  margin: 0 auto 0.75rem;
  padding: 8px;
  background: #ffffff;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
}

.qr-item__img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.qr-item__title {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  font-weight: 600;
  font-size: 0.98rem;
  color: var(--color-text);
  margin-bottom: 0.25rem;
}

.qr-item__title svg {
  width: 18px;
  height: 18px;
  color: var(--color-primary);
}

.qr-item__desc {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

.modal__tip {
  display: flex;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--color-accent-soft);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: var(--color-text);
}

.modal__tip svg {
  width: 20px;
  height: 20px;
  color: var(--color-warning);
  flex-shrink: 0;
  margin-top: 2px;
}

.modal__tip p {
  margin: 0;
}

.modal__direct {
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px dashed var(--color-border);
  text-align: center;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.modal__direct-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  justify-content: center;
  margin-top: 0.75rem;
}

.modal__direct-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.45rem 0.9rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-primary);
  background: var(--color-primary-soft);
  border-radius: var(--radius-full);
  transition: all var(--transition);
}

.modal__direct-link:hover {
  background: var(--color-primary);
  color: #ffffff;
}

.modal__direct-link svg {
  width: 14px;
  height: 14px;
}

/* ---------- 18. Footer ---------- */
.site-footer {
  background: var(--color-bg-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-2xl) 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 2.5rem;
  padding-bottom: var(--space-2xl);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand img {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
}

.footer-brand h3 {
  color: #ffffff;
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 1rem;
}

.footer-social {
  display: flex;
  gap: 0.6rem;
}

.footer-social a {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: rgba(255, 255, 255, 0.7);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.footer-social a:hover {
  background: var(--color-primary-light);
  color: #ffffff;
  transform: translateY(-2px);
}

.footer-social svg {
  width: 18px;
  height: 18px;
}

.footer-col h4 {
  color: #ffffff;
  font-size: 1rem;
  margin-bottom: 1rem;
}

.footer-col ul li {
  margin-bottom: 0.6rem;
}

.footer-col a {
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.92rem;
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--color-accent);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.5rem 0;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.65);
}

.footer-bottom a:hover {
  color: var(--color-accent);
}

.footer-bottom__links {
  display: flex;
  gap: 1.25rem;
  flex-wrap: wrap;
}

/* ---------- 19. Back to top ---------- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-brand);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 900;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-xl);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* ---------- 20. Animations ---------- */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-up {
  opacity: 0;
}

.fade-up.in-view {
  animation: fadeUp 0.7s ease forwards;
}

.fade-up.delay-1 {
  animation-delay: 0.1s;
}
.fade-up.delay-2 {
  animation-delay: 0.2s;
}
.fade-up.delay-3 {
  animation-delay: 0.3s;
}
.fade-up.delay-4 {
  animation-delay: 0.4s;
}

/* ---------- 21. Responsive ---------- */
@media (max-width: 1024px) {
  .hero__inner {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .hero__visual {
    max-width: 560px;
    margin: 0 auto;
  }

  .features-grid,
  .testimonials,
  .platform-grid,
  .value-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .install-steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .community-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

@media (max-width: 768px) {
  .section {
    padding: var(--space-2xl) 0;
  }

  .nav__menu {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 1rem 1.25rem 1.5rem;
    background: #ffffff;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    transform: translateY(-110%);
    transition: transform var(--transition);
    max-height: calc(100vh - var(--header-height));
    overflow-y: auto;
  }

  .nav__menu.open {
    transform: translateY(0);
  }

  .nav__link {
    display: block;
    padding: 0.85rem 1rem;
    border-radius: var(--radius-sm);
    border-bottom: 1px solid var(--color-border);
  }

  .nav__cta {
    margin: 0.85rem 0 0;
    text-align: center;
  }

  .nav__toggle {
    display: flex;
  }

  .hero {
    padding: var(--space-2xl) 0;
  }

  .hero__stats {
    gap: 1.5rem;
  }

  .hero__stat-num {
    font-size: 1.6rem;
  }

  .scenarios,
  .about-grid,
  .docs-layout {
    grid-template-columns: 1fr;
  }

  .docs-sidebar {
    position: static;
  }

  .stats-band__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem 1rem;
  }

  .features-grid,
  .testimonials,
  .platform-grid,
  .install-steps,
  .value-grid,
  .community-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .qr-row {
    grid-template-columns: 1fr;
  }

  .back-to-top {
    bottom: 1.25rem;
    right: 1.25rem;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.85rem;
  }

  h2 {
    font-size: 1.45rem;
  }

  .hero__actions .btn,
  .cta-box__actions .btn {
    width: 100%;
  }

  .stats-band__grid {
    grid-template-columns: 1fr;
  }
}

/* ---------- 22. Print ---------- */
@media print {
  .site-header,
  .back-to-top,
  .modal-overlay,
  .cta-section {
    display: none;
  }
}