/*-------------------------------------------------------------------------------------
                                        ROOT VARIABLES
-------------------------------------------------------------------------------------*/
:root {
    --primary-blue: #0052cc;
    --hero-gradient: linear-gradient(135deg, #0061ff 0%, #0033aa 100%);
    --bg-light: #f8fafc;
    --white: #ffffff;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius: 12px;
    --transition: all 0.3s ease;
  }
  
  /*-------------------------------------------------------------------------------------
                                          GLOBAL RESET
  -------------------------------------------------------------------------------------*/
  *,
  *::before,
  *::after {
    box-sizing: border-box;
  }
  
  html {
    scroll-behavior: smooth;
  }
  
  body {
    margin: 0;
    font-family: "Inter", sans-serif;
    color: var(--text-main);
    background: var(--white);
    line-height: 1.65;
  }
  
  main {
    overflow: hidden;
  }
  
  img {
    max-width: 100%;
    display: block;
  }
  
  a {
    color: var(--primary-blue);
    text-decoration: none;
    transition: var(--transition);
  }
  
  /*-------------------------------------------------------------------------------------
                                        LAYOUT & UTILITIES
  -------------------------------------------------------------------------------------*/
  .container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 16px;
  }
  
  .hero-container {
    max-width: 1240px;
  }
  
  .narrow-container {
    max-width: 900px;
  }
  
  .faq-container {
    max-width: 980px;
  }
  
  .section-padding {
    padding: 72px 0;
  }
  
  .bg-light {
    background: var(--bg-light);
  }
  
  .bg-white {
    background: var(--white);
  }
  
  .page-shell {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 26px;
    align-items: start;
  }
  
  .main-content {
    min-width: 0;
  }
  
  .side-panel {
    display: grid;
    gap: 18px;
  }
  
  .section-header {
    max-width: 760px;
    margin: 0 auto 32px;
    text-align: center;
  }
  
  .section-header.text-left {
    margin-left: 0;
    margin-right: 0;
    text-align: left;
  }
  
  .section-header p:last-child,
  .content-flow p:last-child,
  .disclaimer-content p:last-child {
    margin-bottom: 0;
  }
  
  /*-------------------------------------------------------------------------------------
                                          TYPOGRAPHY
  -------------------------------------------------------------------------------------*/
  h1,
  h2,
  h3 {
    margin-top: 0;
    line-height: 1.2;
    color: var(--text-main);
  }
  
  h1 {
    font-size: clamp(2.3rem, 4vw, 3.4rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: 16px;
  }
  
  h2 {
    font-size: clamp(1.75rem, 3vw, 2.3rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
  }
  
  h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 10px;
  }
  
  p {
    margin: 0 0 16px;
    color: var(--text-muted);
    font-size: 0.98rem;
  }
  
  .eyebrow {
    display: inline-block;
    background: rgba(255, 255, 255, 0.14);
    color: #ffffff;
    padding: 6px 12px;
    border-radius: 999px;
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    margin-bottom: 16px;
    text-transform: uppercase;
  }
  
  .section-label {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--primary-blue);
    margin-bottom: 10px;
  }
  
  .content-flow {
    display: grid;
    gap: 0;
  }
  
  .content-flow p {
    color: var(--text-main);
    line-height: 1.78;
  }
  
  .content-flow a,
  .info-card a,
  .step-card a,
  .benefit-card a,
  .mistake-card a,
  .related-card,
  .side-links a,
  .section-header a {
    color: var(--primary-blue);
  }
  
  .content-flow a,
  .info-card a,
  .step-card a,
  .benefit-card a,
  .mistake-card a,
  .section-header a,
  .side-links a {
    font-weight: 600;
    text-decoration: none;
    text-underline-offset: 3px;
    text-decoration-thickness: 1.5px;
  }
  
  .content-flow a:hover,
  .info-card a:hover,
  .step-card a:hover,
  .benefit-card a:hover,
  .mistake-card a:hover,
  .section-header a:hover,
  .side-links a:hover {
    color: #003ea3;
  }
  
  /*-------------------------------------------------------------------------------------
                                        BREADCRUMB STYLES
  -------------------------------------------------------------------------------------*/
  .breadcrumb {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 26px;
    color: rgba(255, 255, 255, 0.84);
    font-size: 0.9rem;
  }
  
  .breadcrumb a {
    color: rgba(255, 255, 255, 0.92);
  }
  
  .breadcrumb span[aria-current="page"] {
    color: rgba(255, 255, 255, 0.78);
  }
  
  /*-------------------------------------------------------------------------------------
                                           HERO SECTION
  -------------------------------------------------------------------------------------*/
  .investment-hero {
    padding: 56px 0 72px;
    background: var(--hero-gradient);
    color: var(--white);
  }
  
  .hero-content {
    display: grid;
    grid-template-columns: minmax(0, 1.2fr) minmax(300px, 380px);
    gap: 28px;
    align-items: start;
  }
  
  .hero-text {
    max-width: 760px;
  }
  
  .hero-text h1,
  .hero-card h2 {
    color: var(--white);
  }
  
  .hero-intro {
    color: rgba(255, 255, 255, 0.95);
    max-width: 720px;
    font-size: 1.04rem;
  }
  
  .hero-support {
    color: rgba(255, 255, 255, 0.84);
    max-width: 720px;
  }
  
  .hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin-top: 24px;
  }
  
  .hero-card {
    padding: 24px;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.10);
    border: 1px solid rgba(255, 255, 255, 0.18);
    box-shadow: var(--shadow-sm);
  }
  
  .hero-card-badge {
    display: inline-block;
    margin-bottom: 14px;
    padding: 5px 10px;
    font-size: 0.78rem;
    font-weight: 700;
    color: var(--white);
    background: rgba(255, 255, 255, 0.14);
    border-radius: 999px;
  }
  
  .hero-card p,
  .hero-card li {
    color: rgba(255, 255, 255, 0.86);
  }
  
  .hero-card-list {
    margin: 16px 0 0;
    padding-left: 18px;
  }
  
  .hero-card-list li + li {
    margin-top: 8px;
  }
  
  /*-------------------------------------------------------------------------------------
                                            BUTTONS
  -------------------------------------------------------------------------------------*/
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 12px 20px;
    border-radius: 999px;
    font-weight: 700;
    border: 1px solid transparent;
    transition: var(--transition);
  }
  
  .btn-primary,
  .btn-solid {
    background: var(--white);
    color: var(--primary-blue);
    box-shadow: var(--shadow-sm);
  }
  
  .btn-primary:hover,
  .btn-solid:hover {
    transform: translateY(-1px);
  }
  
  .btn-secondary {
    background: transparent;
    color: var(--white);
    border-color: rgba(255, 255, 255, 0.28);
  }
  
  .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
  }
  
  .btn-outline {
    color: var(--primary-blue);
    border-color: var(--border-color);
    background: var(--white);
  }
  
  .btn-outline:hover {
    background: var(--bg-light);
  }
  
  
  /*-------------------------------------------------------------------------------------
                                         SIDEBAR CARDS
  -------------------------------------------------------------------------------------*/
  .side-card {
    background: var(--white);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 20px;
    box-shadow: var(--shadow-sm);
  }
  
  .side-card h3 {
    margin-bottom: 10px;
  }
  
  .side-card p {
    font-size: 0.92rem;
  }
  
  .side-card-icon {
    width: 42px;
    height: 42px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
    border-radius: 12px;
    background: rgba(0, 82, 204, 0.08);
    color: var(--primary-blue);
    font-size: 1rem;
  }
  
  .side-links {
    list-style: none;
    padding: 0;
    margin: 14px 0 0;
  }
  
  .side-links li + li {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid var(--border-color);
  }
  
  .tip-list {
    margin-top: 10px;
  }
  
  .tip-row {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    font-size: 0.9rem;
    padding: 10px 0;
    border-bottom: 1px solid var(--border-color);
  }
  
  .tip-row:last-child {
    border-bottom: 0;
    padding-bottom: 0;
  }
  
  .tip-row span {
    color: var(--text-muted);
  }
  
  .tip-row strong {
    color: var(--text-main);
    font-size: 0.9rem;
  }
  
  /*-------------------------------------------------------------------------------------
                                           GRID LAYOUTS
  -------------------------------------------------------------------------------------*/
  .calculator-grid,
  .method-grid,
  .steps-grid,
  .benefits-grid,
  .mistakes-grid,
  .related-grid,
  .faq-list {
    display: grid;
    gap: 18px;
  }
  
  .calculator-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
    align-items: start;
  }
  
  .method-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  
  .steps-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  
  .benefits-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  
  .mistakes-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  
  .related-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  
  .benefits-intro {
    max-width: 860px;
    margin-bottom: 22px;
  }
  
  /*-------------------------------------------------------------------------------------
                                        SHARED CARD STYLES
  -------------------------------------------------------------------------------------*/
  .tool-card,
  .info-card,
  .step-card,
  .benefit-card,
  .mistake-card,
  .related-card,
  .disclaimer-card,
  .cta-card,
  .feature-panel {
    border-radius: 14px;
    background: var(--white);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
  }
  
  .tool-card,
  .info-card,
  .step-card,
  .benefit-card,
  .mistake-card,
  .related-card {
    padding: 22px;
  }
  
  .tool-card:hover,
  .info-card:hover,
  .step-card:hover,
  .benefit-card:hover,
  .mistake-card:hover,
  .related-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
  }
  
  .feature-panel {
    padding: 28px;
  }
  
  /*-------------------------------------------------------------------------------------
                                      TOOL DIRECTORY CARDS
  -------------------------------------------------------------------------------------*/
  .tool-card {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
  }
  
  .tool-icon {
    width: 46px;
    height: 46px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    border-radius: 12px;
    background: rgba(0, 82, 204, 0.08);
    color: var(--primary-blue);
    font-size: 1rem;
  }
  
  .tool-card h3 {
    margin-bottom: 10px;
  }
  
  .tool-card p {
    font-size: 1rem;
    line-height: 1.7;
    color: #5b6b82;
    margin: 0 0 16px;
  }
  
  .tool-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-top: auto;
    font-weight: 700;
    color: var(--primary-blue);
  }
  
  .tool-link i,
  .related-card span i {
    font-size: 0.86rem;
  }
  
  /*-------------------------------------------------------------------------------------
                                     STEP / BENEFIT / RELATED
  -------------------------------------------------------------------------------------*/
  .step-number {
    display: inline-flex;
    width: 38px;
    height: 38px;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
    border-radius: 50%;
    background: var(--hero-gradient);
    color: var(--white);
    font-weight: 800;
    font-size: 0.95rem;
  }
  
  .benefit-card i {
    display: inline-flex;
    width: 46px;
    height: 46px;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
    border-radius: 12px;
    background: rgba(0, 82, 204, 0.08);
    color: var(--primary-blue);
    font-size: 1rem;
  }
  
  .related-card {
    color: inherit;
  }
  
  .related-card h3 {
    color: var(--text-main);
  }
  
  .related-card p {
    color: #5b6b82;
  }
  
  .related-card span {
    display: inline-flex;
    gap: 8px;
    align-items: center;
    margin-top: 8px;
    color: var(--primary-blue);
    font-weight: 700;
  }
  
  /*-------------------------------------------------------------------------------------
                                           FAQ SECTION
  -------------------------------------------------------------------------------------*/
  .faq-list {
    gap: 12px;
  }
  
  .faq-item {
    border: 1px solid var(--border-color);
    border-radius: 14px;
    background: var(--white);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
  }
  
  .faq-question {
    list-style: none;
    width: 100%;
    padding: 18px 20px;
    border: 0;
    background: transparent;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    text-align: left;
    cursor: pointer;
    font: inherit;
    color: var(--text-main);
    font-weight: 700;
  }
  
  .faq-question::-webkit-details-marker {
    display: none;
  }
  
  .faq-question i {
    color: var(--primary-blue);
    transition: var(--transition);
    flex-shrink: 0;
  }
  
  .faq-item[open] .faq-question i {
    transform: rotate(45deg);
  }
  
  .faq-answer p {
    padding: 0 20px 18px;
    margin: 0;
  }
  
  /*-------------------------------------------------------------------------------------
                                    DISCLAIMER & CTA SECTION
  -------------------------------------------------------------------------------------*/
  .disclaimer-card {
    display: grid;
    grid-template-columns: 64px 1fr;
    gap: 18px;
    padding: 24px;
    align-items: start;
  }
  
  .disclaimer-icon {
    width: 54px;
    height: 54px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: rgba(0, 82, 204, 0.08);
    color: var(--primary-blue);
    font-size: 1.1rem;
  }
  
  .cta-card {
    padding: 36px 28px;
    text-align: center;
  }
  
  .cta-card p {
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
  }
  
  .cta-actions {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 14px;
    margin-top: 20px;
    flex-wrap: wrap;
  }
  
  /*-------------------------------------------------------------------------------------
                                       RESPONSIVE STYLES
  -------------------------------------------------------------------------------------*/
  @media (max-width: 1100px) {
    .page-shell {
      grid-template-columns: 1fr;
    }
  
    .side-panel {
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }
  
    .steps-grid {
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }
  
    .mistakes-grid,
    .benefits-grid,
    .related-grid {
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }
  }
  
  @media (max-width: 900px) {
    .section-padding {
      padding: 62px 0;
    }
  
    .hero-content,
    .calculator-grid,
    .method-grid,
    .toc-card {
      grid-template-columns: 1fr;
    }
  
    .hero-text {
      max-width: 100%;
    }
  
    .side-panel {
      grid-template-columns: 1fr;
    }
  }
  
  @media (max-width: 680px) {
    .investment-hero {
      padding: 42px 0 56px;
    }
  
    .section-padding {
      padding: 54px 0;
    }
  
    .steps-grid,
    .benefits-grid,
    .mistakes-grid,
    .related-grid {
      grid-template-columns: 1fr;
    }
  
    .tool-card,
    .info-card,
    .step-card,
    .benefit-card,
    .mistake-card,
    .related-card,
    .side-card,
    .feature-panel,
    .cta-card,
    .disclaimer-card {
      padding: 20px;
    }
  
    .faq-question {
      padding: 16px 18px;
    }
  
    .faq-answer p {
      padding: 0 18px 16px;
    }
  
    .disclaimer-card {
      grid-template-columns: 1fr;
    }
  
    .toc-card a {
      min-height: auto;
    }
  }