/* =========================================================
   EstudyLog  -  Global Styles (Dark, Accessible, Responsive)
   ========================================================= */

/* ---------- Design tokens ---------- */
:root{
  /* Brand */
  --primary: #3b82f6;           /* blue-500 */
  --primary-dark: #1d4ed8;      /* blue-700 */
  --secondary: #60a5fa;         /* blue-400 */

  /* Surfaces (dark) */
  --dark: #0f172a;              /* slate-900 */
  --light: #1e293b;             /* slate-800 (section bg) */
  --panel: #111826;             /* slightly darker than 1e293b to separate cards */
  --panel-quiet: #0e1422;       /* subtle quiet panel */

  /* Text */
  --text-primary: #f8fafc;      /* near-white */
  --text-secondary: #cbd5e1;    /* slate-300 */
  --text-muted: #94a3b8;        /* slate-400 */

  /* Layout */
  --border-radius: 16px;
  --radius: var(--border-radius);
  --max-width: 1200px;

  /* Effects */
  --focus-ring: 0 0 0 3px rgba(59,130,246,.45);
  --shadow-sm: 0 6px 18px rgba(0,0,0,.12);
  --shadow-md: 0 10px 24px rgba(0,0,0,.18);
  --shadow-lg: 0 16px 36px rgba(0,0,0,.25);

  /* Anim */
  --transition: all .25s ease;

  color-scheme: dark; /* native dark controls */
}

/* ---------- Global resets & basics ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0;
  background: var(--dark);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Respect [hidden] everywhere */
*[hidden]{ display: none !important; }

/* Links & focus states */
a { color: var(--text-secondary); text-decoration: none; }
a:hover { color: var(--text-primary); }
:where(a, button, [role="button"], input, select, textarea):focus-visible{
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: 10px;
}

/* Base forms so controls look correct on any page */
:where(input, textarea, select){
  background: var(--light);
  color: var(--text-primary);
  border: 1px solid rgba(255,255,255,.08);
  border-radius: 12px;
}
:where(input, textarea)::placeholder{ color: var(--text-muted); }

/* Motion safety */
@media (prefers-reduced-motion: reduce){
  *{ animation: none !important; transition: none !important; }
}

/* Images never overflow */
img { max-width: 100%; height: auto; display: block; }

/* ---------- Layout helpers ---------- */
.container{ max-width: var(--max-width); margin: 0 auto; padding: 0 2rem; }
.section{ padding: 5rem 2rem; }

/* ---------- Navbar (header partial) ---------- */
.navbar{
  position: sticky; top: 0; width: 100%;
  background: rgba(16,22,38,.7);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid rgba(255,255,255,.06);
  z-index: 1000;
  padding: 0.9rem 0;
  transition: var(--transition);
}
.navbar.scrolled{ background: rgba(16,22,38,.9); }
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))){
  .navbar{ background: rgba(16,22,38,.92); }
}

.nav-container{
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem;
  display: flex; align-items: center; justify-content: space-between;
}

.logo{ display: flex; align-items: center; gap: .75rem; color: #fff; }
.logo-icon{ width: 32px; height: 32px; border-radius: 8px; flex-shrink: 0; }
.logo-text{ font-weight: 700; font-size: 1.1rem; color: #fff; }

.nav-menu{ display: flex; align-items: center; gap: 2rem; }
.nav-link{ color: var(--text-secondary); }
.nav-link:hover{ color: var(--text-primary); }
.nav-link.active{
  color: #fff;
  font-weight: 600;
  position: relative;
}
.nav-link.active::after{
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -6px;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  border-radius: 999px;
}
.nav-cta{
  color: #fff;
  padding: .65rem 1.15rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  box-shadow: 0 10px 24px rgba(31,79,185,.25);
}

/* Mobile menu button (header partial) */
.mobile-menu-toggle{
  display: none; color: #fff; background: none; border: none; cursor: pointer;
  flex-direction: column; gap: 4px; padding: .5rem;
}
.mobile-menu-toggle span{
  width: 20px; height: 2px; background: currentColor; transition: var(--transition);
}

/* ---------- Hero ---------- */
.hero.hero--simple{
  padding: 8rem 2rem 4rem;
  min-height: 70vh;
  display: flex; align-items: center;
  background:
    radial-gradient(1200px 600px at 20% -10%, rgba(48,92,196,.35), transparent 60%),
    radial-gradient(1000px 600px at 100% 20%, rgba(33,63,150,.25), transparent 60%),
    linear-gradient(135deg, #0d1326 0%, #1a2d68 100%);
}
.hero-content{
  text-align: center;
  max-width: 820px;
  margin: 0 auto;
}
.hero-title{
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  color: var(--text-primary);
  margin: 0 0 1rem;
}
.highlight{
  background: linear-gradient(90deg, #fbbf24, #f59e0b);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-description{
  color: var(--text-secondary);
  font-size: 1.15rem;
  margin-bottom: 1.5rem;
}

/* App Store button */
.cta-buttons{ display: flex; justify-content: center; margin: 1.25rem 0 1.5rem; }
.app-store-btn{ display: inline-block; }
.app-store-container{
  display: flex; align-items: center; gap: 12px;
  background: #000; color: #fff;
  padding: 12px 20px; border-radius: 12px;
  min-width: 200px;
  box-shadow: 0 4px 12px rgba(0,0,0,.3);
  transition: var(--transition);
}
.app-store-btn:hover .app-store-container{
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0,0,0,.4);
}
.apple-logo{ width: 24px; height: 24px; flex-shrink: 0; }
.app-store-text{ display: flex; flex-direction: column; line-height: 1.2; }
.download-text{ font-size: 12px; color: rgba(255,255,255,.8); }
.store-name{ font-size: 18px; font-weight: 600; color: #fff; }

/* ---------- How it works ---------- */
.how{ background: var(--light); }
.section-title{
  text-align: center;
  font-size: 2.2rem;
  font-weight: 800;
  margin: 0;
  background: linear-gradient(135deg, var(--text-primary), var(--secondary));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.section-subtitle{
  text-align: center;
  color: var(--text-secondary);
  margin: .5rem 0 2.2rem;
}

.steps-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
}
.step-card{
  background: var(--panel);
  border: 1px solid rgba(255,255,255,.06);
  border-radius: 16px;
  padding: 1.4rem;
  box-shadow: var(--shadow-sm);
}
.step-emoji{ font-size: 1.6rem; margin-bottom: .5rem; }
.step-card h3{ color: var(--text-primary); margin: 0 0 .25rem; font-size: 1.1rem; }
.step-card p{ color: var(--text-secondary); margin: 0; }

/* ---------- Features ---------- */
.features{ background: var(--dark); }
.features-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit,minmax(280px,1fr));
  gap: 1.5rem;
}
.feature-card{
  background: var(--panel);
  border: 1px solid rgba(255,255,255,.06);
  border-radius: 20px;
  padding: 1.6rem;
  transition: transform .2s ease, box-shadow .2s ease;
  box-shadow: var(--shadow-sm);
}
.feature-card:hover{
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}
.feature-icon{
  width: 52px; height: 52px; border-radius: 14px;
  display:flex; align-items:center; justify-content:center;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff; margin-bottom: 1rem; font-size: 1.3rem;
}
.feature-card h3{ color: var(--text-primary); margin: 0 0 .4rem; }
.feature-card p{ color: var(--text-secondary); line-height: 1.7; margin: 0; }

/* ---------- Value Section ---------- */
.value{ background: var(--light); }
.value-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}
.value-card{
  background: var(--panel);
  border-radius: 18px;
  border: 1px solid rgba(255,255,255,.06);
  padding: 1.8rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.value-card h3{
  margin: 0;
  color: var(--text-primary);
  font-size: 1.25rem;
}
.value-card p{
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.7;
}
.value-icon{
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: rgba(59,130,246,.18);
  color: var(--primary);
  font-size: 1.4rem;
}

/* ---------- AI Section ---------- */
.ai-section{
  background: linear-gradient(135deg, #13265e, #243b91);
  position: relative;
  overflow: hidden;
  color: #fff;
}
.ai-section::after{
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(600px 320px at 20% 20%, rgba(255,255,255,.18), transparent),
              radial-gradient(500px 280px at 80% 40%, rgba(79,70,229,.25), transparent);
  opacity: .7;
  pointer-events: none;
}
.ai-section .container{
  position: relative;
  z-index: 1;
}
.ai-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
}
.ai-card{
  background: rgba(15,23,42,.6);
  border-radius: 20px;
  padding: 1.75rem;
  border: 1px solid rgba(148,163,184,.25);
  backdrop-filter: blur(14px);
  box-shadow: 0 20px 35px rgba(15,23,42,.35);
}
.ai-card h3{
  margin: 0 0 .75rem;
  color: #f8fafc;
  font-size: 1.25rem;
}
.ai-card p{
  margin: 0;
  color: rgba(226,232,240,.85);
  line-height: 1.7;
}

/* ---------- Resource Section ---------- */
.resource{
  background: var(--dark);
}
.resource-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}
.resource-card{
  background: var(--panel);
  border-radius: 16px;
  border: 1px solid rgba(255,255,255,.06);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: .75rem;
  transition: transform .2s ease, box-shadow .2s ease;
}
.resource-card:hover{
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.resource-card h3{
  margin: 0;
  color: var(--text-primary);
  font-size: 1.15rem;
}
.resource-card p{
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.6;
}
.resource-card a{
  color: var(--primary);
  font-weight: 600;
  text-decoration: none;
}
.resource-card a:hover{ color: var(--secondary); }

/* ---------- Testimonials ---------- */
.testimonials{ background: var(--light); }
.testimonials-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit,minmax(300px,1fr));
  gap: 1.5rem; margin-top: 2rem;
}
.testimonial-card{
  background: var(--panel);
  border: 1px solid rgba(255,255,255,.06);
  border-radius: 16px;
  padding: 1.5rem;
  transition: transform .2s ease, box-shadow .2s ease;
  box-shadow: var(--shadow-sm);
}
.testimonial-card:hover{ transform: translateY(-2px); box-shadow: var(--shadow-md); }
.testimonial-content p{
  color: var(--text-secondary); font-style: italic; margin: 0 0 1rem; line-height: 1.6;
}
.testimonial-author{ border-top: 1px solid rgba(255,255,255,.1); padding-top: 1rem; }
.author-name{ color: var(--text-primary); font-weight: 600; margin-bottom: .25rem; }
.author-info{ color: var(--text-muted); font-size: .9rem; }

/* ---------- CTA ---------- */
.cta-section.cta--simple{
  background: linear-gradient(135deg, #13265e, #2b56c2);
  color: #fff; text-align: center;
}
.cta-title{ color:#fff; font-size: clamp(1.6rem, 4vw, 2.1rem); margin: 0 0 .5rem; }
.cta-subtitle{ color: rgba(255,255,255,.88); margin: 0 0 1.4rem; }

/* ---------- Footer (footer partial) ---------- */
.footer{
  background: var(--dark); color: var(--text-secondary);
  padding: 3rem 0 1rem;
}
.footer-container{ max-width: var(--max-width); margin: 0 auto; padding: 0 2rem; }
.footer-content{
  display:grid; grid-template-columns: repeat(auto-fit,minmax(250px,1fr));
  gap: 2rem; margin-bottom: 2rem;
}
.footer-section h3, .footer-section h4{
  color: var(--text-primary); margin: 0 0 1rem; font-size: 1.1rem;
}
.footer-desc{ color: var(--text-secondary); line-height: 1.6; margin: 0 0 1.5rem; }

.footer-links{ list-style: none; padding: 0; margin: 0; }
.footer-links li{ margin-bottom: .5rem; }
.footer-links a{ color: var(--text-secondary); }
.footer-links a:hover{ color: var(--text-primary); }

.footer-app-store{ display: flex; justify-content: center; }
.footer-app-store .app-store-container{
  background: rgba(255,255,255,.1);
  padding: 8px 16px; gap: 8px; min-width: 160px;
}
.footer-app-store:hover .app-store-container{
  background: rgba(255,255,255,.2);
}

.footer-bottom{
  border-top: 1px solid rgba(255,255,255,.1);
  padding-top: 1.5rem; text-align: center; color: var(--text-secondary);
}
.footer-tagline{ margin-top: .5rem; font-size: .9rem; }

/* Footer guardrails: never let images get huge */
.footer img{
  max-width: 56px; max-height: 56px; width: auto; height: auto;
  border-radius: 12px; box-shadow: 0 2px 10px rgba(0,0,0,.2);
}
.footer .hero-appicon{
  width: 56px !important; max-height: 56px !important;
}

/* ---------- Content Pages ---------- */
.page-wrapper{
  padding: 4rem 0 5rem;
}
.back-link{
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  color: var(--primary);
  text-decoration: none;
  margin-bottom: 2rem;
  font-weight: 600;
  transition: color .2s ease;
}
.back-link:hover{ color: var(--secondary); }

.page-container{
  max-width: 840px;
  margin: 0 auto;
  background: var(--panel);
  border-radius: var(--border-radius);
  padding: clamp(1.75rem, 3vw, 2.4rem);
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(255,255,255,.06);
}
.page-title{
  color: var(--primary);
  font-size: clamp(2.2rem, 5vw, 2.8rem);
  font-weight: 800;
  margin: 0 0 1rem;
  text-align: center;
}
.page-subtitle{
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 2rem;
  text-align: center;
  font-size: 1.05rem;
  line-height: 1.7;
}
.page-meta{
  text-align: center;
  color: var(--text-muted);
  font-size: .95rem;
  margin-bottom: 1rem;
}

.page-content{
  color: var(--text-secondary);
  line-height: 1.8;
  font-size: 1rem;
}
.page-content h2{
  color: var(--text-primary);
  font-size: clamp(1.6rem, 3vw, 1.9rem);
  margin: 2.2rem 0 1rem;
  font-weight: 800;
}
.page-content h3{
  color: var(--text-primary);
  font-size: 1.25rem;
  margin: 1.6rem 0 .75rem;
  font-weight: 700;
}
.page-content p{
  margin: 0 0 1rem;
}
.page-content ul,
.page-content ol{
  margin: 0 0 1.25rem;
  padding-left: 1.5rem;
}
.page-content li{
  margin-bottom: .6rem;
}
.page-content a{
  color: var(--primary);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}
.page-content a:hover{ color: var(--secondary); }

.stats-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1.25rem;
  margin: 2.5rem 0;
}
.stat-item{
  background: var(--panel-quiet);
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,.08);
  padding: 1.25rem;
  text-align: center;
}
.stat-number{
  display: block;
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: .35rem;
}
.stat-label{
  font-size: .95rem;
  color: var(--text-secondary);
}

.team-grid{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.75rem;
  margin: 2.5rem 0;
}
.team-member{
  text-align: center;
  padding: 1.5rem;
  background: var(--panel-quiet);
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.08);
  box-shadow: var(--shadow-sm);
}
.team-member h4{
  color: var(--text-primary);
  margin: 0 0 .5rem;
}
.team-member .role{
  color: var(--primary);
  font-weight: 700;
  margin-bottom: 1rem;
}

.tip-card{
  background: var(--panel-quiet);
  border-radius: 14px;
  padding: 1.5rem;
  border-left: 4px solid var(--primary);
  margin: 1.25rem 0;
  box-shadow: var(--shadow-sm);
}
.tip-card h3{
  margin-top: 0;
  margin-bottom: .5rem;
  color: var(--text-primary);
}
.tip-card p{ margin: 0; }

.quote{
  font-style: italic;
  color: var(--text-muted);
  border-left: 4px solid var(--secondary);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
}

.faq-item{
  background: var(--panel-quiet);
  border-radius: 14px;
  padding: 1.5rem;
  border: 1px solid rgba(255,255,255,.08);
  margin: 1rem 0;
  box-shadow: var(--shadow-sm);
}
.faq-question{
  color: var(--text-primary);
  font-weight: 700;
  margin-bottom: .6rem;
  font-size: 1.1rem;
}
.faq-answer{
  color: var(--text-secondary);
  margin: 0;
}

.contact-methods{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.25rem;
  margin: 2rem 0 3rem;
}
.contact-method{
  background: var(--panel-quiet);
  border-radius: 14px;
  padding: 1.6rem;
  text-align: left;
  border: 1px solid rgba(255,255,255,.08);
  box-shadow: var(--shadow-sm);
}
.contact-method h3{
  margin: 0 0 .75rem;
  color: var(--text-primary);
}
.contact-method p{
  color: var(--text-secondary);
  margin: 0 0 1rem;
}
.contact-method a{
  color: var(--primary);
  font-weight: 600;
  text-decoration: none;
}
.contact-method a:hover{ color: var(--secondary); }

.page-callout{
  background: rgba(96,165,250,.12);
  border: 1px solid rgba(96,165,250,.35);
  border-radius: 14px;
  padding: 1.5rem;
  margin: 2.5rem 0;
  color: var(--text-secondary);
}
.page-callout strong{
  color: var(--text-primary);
}

.page-list{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}
.page-list-item{
  padding: 1.25rem;
  border-radius: 14px;
  background: var(--panel-quiet);
  border: 1px solid rgba(255,255,255,.08);
  box-shadow: var(--shadow-sm);
}
.page-list-item h3{
  color: var(--text-primary);
  margin: 0 0 .7rem;
}
.page-list-item p{
  color: var(--text-secondary);
  margin: 0;
}

.page-divider{
  border: none;
  border-top: 1px solid rgba(255,255,255,.08);
  margin: 2.5rem 0;
}

.page-cta{
  text-align: center;
  margin: 3rem 0 1.5rem;
}
.page-cta .app-store-container{
  margin: 0 auto;
}

.page-note{
  color: var(--text-muted);
  font-size: .95rem;
  margin-top: -0.25rem;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px){
  .mobile-menu-toggle{ display: flex; }
  .nav-container{ padding: 0 1rem; }

  .nav-menu{
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    background: rgba(16,22,38,.95);
    -webkit-backdrop-filter: saturate(140%) blur(14px);
    backdrop-filter: saturate(140%) blur(14px);
    border-top: 1px solid rgba(255,255,255,.06);
    padding: 1rem 2rem;
    flex-direction: column; gap: 1rem;
  }
  .nav-menu.active{ display: flex; }
  .nav-menu .nav-link{ padding: .5rem 0; border-bottom: 1px solid rgba(255,255,255,.1); }
  .nav-menu .nav-cta{ margin-top: .5rem; text-align: center; }

  .hero.hero--simple{ padding: 6rem 1rem 3rem; }
  .section{ padding: 3.5rem 1rem; }

  .page-container{ padding: 1.5rem; }
  .page-list{ grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
  .contact-methods{ gap: 1rem; }
  .value-grid, .ai-grid, .resource-grid{
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  }
}

@media (max-width: 600px){
  .app-store-container{ padding: 10px 16px; min-width: 180px; gap: 10px; }
  .apple-logo{ width: 22px; height: 22px; }
  .download-text{ font-size: 11px; }
  .store-name{ font-size: 16px; }

  .footer-container{ padding: 0 1rem; }
  .footer-content{ grid-template-columns: 1fr; gap: 1.5rem; text-align: center; }
  .footer-links{ display: flex; flex-wrap: wrap; justify-content: center; gap: 1rem; }
  .footer-bottom{ font-size: .9rem; }
  .footer-tagline{ font-size: .85rem; margin-top: .75rem; }

  .page-container{ padding: 1.25rem; }
  .page-list, .contact-methods, .team-grid, .stats-grid{
    grid-template-columns: 1fr;
  }
  .value-grid, .ai-grid, .resource-grid{
    grid-template-columns: 1fr;
  }
  .page-title{ font-size: clamp(2rem, 6vw, 2.4rem); }
  .page-subtitle{ text-align: left; }
  .back-link{ margin-bottom: 1.5rem; }
}