/* ==========================================================================
   FOGLIO DI STILE DEL SITO
   --------------------------------------------------------------------------
   Indice
   1.  Colori, font e misure (variabili)
   2.  Base
   3.  Layout generale
   4.  Header e menu
   5.  Bottoni e link
   6.  Home: apertura (hero)
   7.  Home: materie, approccio e metodo
   8.  Citazione
   9.  Recensioni
   10. Invito al contatto
   11. Pagine interne: intestazione
   12. Chi sono
   13. Servizi
   14. Contatti e modulo
   15. Testi lunghi (privacy, futuri articoli)
   16. Footer
   17. Utility e accessibilità
   ========================================================================== */


/* 1. COLORI, FONT E MISURE ------------------------------------------------- */

:root {
  /* Palette del brand: cambia qui e cambia tutto il sito */
  --blu-profondo:  #17365D;
  --blu-didattico: #2864A5;
  --azzurro-chiaro:#C8E1F2;
  --bianco-caldo:  #F7F8F5;
  --verde-petrolio:#176B68;
  --grigio-ardesia:#344054;

  /* Ruoli dei colori (modalità chiara) */
  --bg:              var(--bianco-caldo);
  --surface:         #FFFFFF;
  --surface-soft:    #EBF3F9;
  --surface-didattica: var(--azzurro-chiaro);
  --text:            var(--grigio-ardesia);
  --text-muted:      #5A6577;
  --heading:         var(--blu-profondo);
  --link:            var(--blu-didattico);
  --accent:          var(--verde-petrolio);
  --border:          #DCE3EA;
  --btn-bg:          var(--blu-didattico);
  --btn-bg-hover:    var(--blu-profondo);
  --btn-text:        #FFFFFF;
  --band-bg:         var(--blu-profondo);
  --band-text:       var(--bianco-caldo);
  --band-muted:      var(--azzurro-chiaro);
  --header-bg:       rgba(247, 248, 245, 0.9);
  --deco:            var(--blu-didattico);

  /* Colore di ogni materia */
  --c-matematica: var(--blu-didattico);
  --c-fisica:     var(--blu-profondo);
  --c-chimica:    var(--verde-petrolio);

  /* Tipografia */
  --font-titoli: "Manrope", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-testo:  "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-formule: "Cambria Math", "STIX Two Math", "Latin Modern Math", Cambria, Georgia, serif;

  /* Misure */
  --container: 1160px;
  --radius-lg: 28px;
  --radius:    16px;
  --radius-sm: 10px;
  --section-y: clamp(4.5rem, 9vw, 7.5rem);
  --header-h:  76px;
}

/* Variante scura: si attiva da sola se il dispositivo è in modalità scura.
   Per disattivarla, cancella l'intero blocco @media qui sotto. */
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg:              #0E1F35;
    --surface:         #132A47;
    --surface-soft:    #12294A;
    --surface-didattica: #1A3A5E;
    --text:            #D3DCE6;
    --text-muted:      #9DAEC1;
    --heading:         #F7F8F5;
    --link:            #9CCAEC;
    --accent:          #5FBDB7;
    --border:          #26425F;
    --btn-bg:          var(--blu-didattico);
    --btn-bg-hover:    #3A7BC0;
    --btn-text:        #FFFFFF;
    --band-bg:         #0A1729;
    --band-text:       #F7F8F5;
    --band-muted:      #C8E1F2;
    --header-bg:       rgba(14, 31, 53, 0.9);
    --deco:            #9CCAEC;
    --c-matematica: #7FB4E6;
    --c-fisica:     #C8E1F2;
    --c-chimica:    #5FBDB7;
  }
}


/* 2. BASE ------------------------------------------------------------------ */

*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1rem);
}

body {
  margin: 0;
  font-family: var(--font-testo);
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-titoli);
  color: var(--heading);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.6em;
  font-weight: 700;
  text-wrap: balance;
}
h1 { font-size: clamp(2.35rem, 5.2vw, 3.5rem); font-weight: 800; letter-spacing: -0.03em; }
h2 { font-size: clamp(1.8rem, 3.4vw, 2.45rem); }
h3 { font-size: 1.3rem; letter-spacing: -0.01em; }
h4 { font-size: 1rem; letter-spacing: 0; }

p { margin: 0 0 1.1em; max-width: 68ch; text-wrap: pretty; }

a { color: var(--link); text-underline-offset: 0.2em; text-decoration-thickness: 1px; }
a:hover { color: var(--heading); }

:focus-visible {
  outline: 3px solid var(--link);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection { background: var(--azzurro-chiaro); color: var(--blu-profondo); }

sub { font-size: 0.7em; }


/* 3. LAYOUT GENERALE ------------------------------------------------------- */

.container {
  width: min(100% - 2.5rem, var(--container));
  margin-inline: auto;
}

.section { padding-block: var(--section-y); }
.section--soft { background: var(--surface-soft); }
.section--tight { padding-top: 0; }

.section-head { max-width: 680px; margin-bottom: clamp(2.5rem, 5vw, 3.5rem); }
.section-head p { color: var(--text-muted); font-size: 1.125rem; margin-bottom: 0; }

.lead { font-size: clamp(1.125rem, 1.6vw, 1.25rem); line-height: 1.6; }

.note { font-size: 0.95rem; color: var(--text-muted); }


/* 4. HEADER E MENU --------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--header-bg);
  -webkit-backdrop-filter: saturate(1.4) blur(10px);
  backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}
.site-header.is-scrolled { border-bottom-color: var(--border); }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: var(--header-h);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--heading);
  text-decoration: none;
}
.brand:hover { color: var(--heading); }
.brand__mark { width: 40px; height: 40px; flex: none; }
.brand__mark .brand__dot { fill: var(--accent); }
.brand__name {
  display: block;
  font-family: var(--font-titoli);
  font-weight: 800;
  font-size: 1.08rem;
  line-height: 1.15;
  letter-spacing: -0.01em;
}
.brand__tag {
  display: block;
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.3;
}

@media (max-width: 480px) {
  .brand__tag { display: none; }
}

.nav__list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav__link {
  position: relative;
  display: block;
  padding: 0.5rem 0.9rem;
  font-family: var(--font-titoli);
  font-weight: 600;
  font-size: 0.97rem;
  color: var(--heading);
  text-decoration: none;
  border-radius: 999px;
}
.nav__link:hover { background: var(--surface-soft); color: var(--heading); }
.nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0.9rem;
  right: 0.9rem;
  bottom: 0.2rem;
  height: 2px;
  border-radius: 2px;
  background: var(--accent);
}
.nav__cta { margin-left: 0.6rem; }

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  color: var(--heading);
  cursor: pointer;
}
.nav-toggle__bars,
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  display: block;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.2s ease, opacity 0.2s ease;
}
.nav-toggle__bars { position: relative; }
.nav-toggle__bars::before,
.nav-toggle__bars::after { content: ""; position: absolute; left: 0; }
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after  { top: 6px; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after  { transform: translateY(-6px) rotate(-45deg); }

@media (max-width: 880px) {
  .nav-toggle { display: inline-flex; }
  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    padding: 0.75rem 1.25rem 1.5rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
  }
  .nav.is-open { opacity: 1; visibility: visible; transform: none; }
  .nav__list { flex-direction: column; align-items: stretch; gap: 0.15rem; }
  .nav__link { padding: 0.85rem 1rem; font-size: 1.08rem; border-radius: 12px; }
  .nav__link[aria-current="page"]::after { left: 1rem; right: auto; width: 26px; bottom: 0.45rem; }
  .nav__cta { margin: 0.75rem 0 0; }
  .nav__cta .btn { width: 100%; justify-content: center; }
}


/* 5. BOTTONI E LINK -------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 1.45rem;
  border: 2px solid transparent;
  border-radius: 999px;
  font-family: var(--font-titoli);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}
.btn--primary { background: var(--btn-bg); color: var(--btn-text); }
.btn--primary:hover { background: var(--btn-bg-hover); color: var(--btn-text); }
.btn--outline { border-color: var(--border); background: transparent; color: var(--heading); }
.btn--outline:hover { border-color: var(--heading); color: var(--heading); }
.btn--small { padding: 0.6rem 1.15rem; font-size: 0.95rem; }

.text-link {
  font-family: var(--font-titoli);
  font-weight: 700;
  color: var(--link);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--link) 35%, transparent);
  text-underline-offset: 0.3em;
}
.text-link:hover { color: var(--heading); text-decoration-color: currentColor; }


/* 6. HOME: APERTURA (HERO) ------------------------------------------------- */

.hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(3rem, 7vw, 5.5rem) clamp(4rem, 8vw, 6.5rem);
}
.hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}
.hero h1 { max-width: 15ch; }
.hero .lead { max-width: 34rem; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2rem; }
.hero__fact {
  margin-top: 2.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
  max-width: 34rem;
  font-size: 0.97rem;
  color: var(--text-muted);
}
.hero__fact strong { color: var(--heading); font-weight: 600; }

/* Illustrazione: molecola di caffeina, orbite e funzione */
.hero__visual { width: 100%; max-width: 520px; justify-self: center; }
.art-disc     { fill: var(--surface-soft); }
.art-grid     { stroke: var(--link); stroke-width: 1; opacity: 0.16; }
.art-axis     { stroke: var(--link); stroke-width: 1.5; opacity: 0.4; }
.art-wave     { fill: none; stroke: var(--accent); stroke-width: 2.5; stroke-linecap: round; opacity: 0.75; }
.art-orbit    { fill: none; stroke: var(--link); stroke-width: 1.5; stroke-dasharray: 3 7; opacity: 0.6; }
.art-electron { fill: var(--accent); }
.art-electron--alt { fill: var(--link); }
.mol-bond     { fill: none; stroke: var(--heading); stroke-width: 3; stroke-linecap: round; stroke-linejoin: round; }
.mol-atom     { fill: var(--bg); stroke: var(--heading); stroke-width: 2.5; }
.mol-atom--o  { stroke: var(--accent); }
.mol-end      { fill: var(--heading); }
.mol-label {
  font-family: var(--font-titoli);
  font-weight: 800;
  font-size: 17px;
  fill: var(--heading);
  text-anchor: middle;
  dominant-baseline: central;
}
.mol-atom--o + .mol-label { fill: var(--accent); }
.art-note {
  font-family: var(--font-formule);
  font-style: italic;
  font-size: 15px;
  fill: var(--text-muted);
}
.art-note--name { font-family: var(--font-testo); font-style: normal; font-size: 12px; letter-spacing: 0.02em; }
.art-note--chem { font-family: var(--font-titoli); font-style: normal; font-weight: 600; font-size: 14px; }
.art-leader { stroke: var(--text-muted); stroke-width: 1; opacity: 0.55; }

@media (max-width: 880px) {
  .hero__inner { grid-template-columns: 1fr; }
  .hero__visual { max-width: 380px; }
}


/* 7. HOME: MATERIE, APPROCCIO E METODO ------------------------------------- */

.subjects {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.5rem, 4vw, 3rem);
}
.subject-col {
  --c: var(--c-matematica);
  padding-top: 1.5rem;
  border-top: 3px solid var(--c);
}
.subject-col--fisica  { --c: var(--c-fisica); }
.subject-col--chimica { --c: var(--c-chimica); }
.subject-col__icon { width: 44px; height: 44px; color: var(--c); margin-bottom: 1.1rem; }
.subject-col h3 { font-size: 1.5rem; margin-bottom: 0.5rem; }
.subject-col p { color: var(--text); }
.subject-col .formula-hint {
  display: block;
  margin-bottom: 0.9rem;
  font-family: var(--font-formule);
  font-style: italic;
  font-size: 1.05rem;
  color: var(--text-muted);
}
.subject-col .formula-hint--chem { font-style: normal; }

@media (max-width: 820px) {
  .subjects { grid-template-columns: 1fr; gap: 2.5rem; }
}

.approach {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(2rem, 6vw, 5rem);
  align-items: start;
}
.approach__text p { font-size: 1.08rem; }
.keywords {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  margin: 1.75rem 0 0;
  padding: 0;
}
.keywords li {
  padding: 0.35rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 0.9rem;
  color: var(--heading);
  background: var(--surface);
}

/* Riquadro del metodo: tre passaggi legati come atomi in una catena */
.method {
  position: relative;
  padding: clamp(1.75rem, 4vw, 2.75rem);
  border-radius: var(--radius-lg);
  background: var(--surface-didattica);
}
.method h3 { font-size: 1.4rem; margin-bottom: 1.75rem; }
.steps {
  position: relative;
  display: grid;
  gap: 1.75rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.step {
  position: relative;
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 1.1rem;
  align-items: start;
}
.step:not(:last-child)::before {
  /* il legame che unisce un passaggio al successivo */
  content: "";
  position: absolute;
  left: 22.5px;
  top: 48px;
  bottom: -1.75rem;
  width: 3px;
  background: var(--heading);
  opacity: 0.22;
}
.step__num {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 2.5px solid var(--heading);
  background: var(--surface-didattica);
  font-family: var(--font-titoli);
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--heading);
}
.step:last-child .step__num { background: var(--accent); border-color: var(--accent); color: var(--btn-text); }
.step h4 { font-size: 1.1rem; margin: 0.6rem 0 0.25rem; }
.step p { margin: 0; color: var(--heading); opacity: 0.9; }

@media (max-width: 880px) {
  .approach { grid-template-columns: 1fr; }
}


/* 8. CITAZIONE ------------------------------------------------------------- */

.quote-band {
  position: relative;
  overflow: hidden;
  padding-block: clamp(5rem, 10vw, 8rem);
  background: var(--band-bg);
  color: var(--band-text);
}
.quote-band__pattern {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  color: var(--band-muted);
  opacity: 0.07;
  pointer-events: none;
}
.quote {
  position: relative;
  max-width: 920px;
  margin-inline: auto;
  text-align: center;
}
.quote__flame { width: 64px; height: 80px; margin: 0 auto 2rem; color: var(--band-muted); }
.quote blockquote { margin: 0; }
.quote__text {
  margin: 0 auto;
  max-width: 24ch;
  font-family: var(--font-titoli);
  font-weight: 700;
  font-size: clamp(1.8rem, 4.4vw, 3.2rem);
  line-height: 1.18;
  letter-spacing: -0.025em;
  color: var(--band-text);
  text-wrap: balance;
}
.quote__cite {
  display: block;
  margin-top: 1.25rem;
  font-style: normal;
  font-size: 0.95rem;
  color: var(--band-muted);
}
.quote__wink { margin-top: 3rem; }
.quote__wink p {
  margin: 0 auto 1rem;
  font-family: var(--font-titoli);
  font-weight: 600;
  font-size: clamp(1.15rem, 2vw, 1.35rem);
  color: var(--band-text);
}
.reaction {
  display: inline-flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: baseline;
  gap: 0.2em 0.55em;
  padding: 0.7rem 1.3rem;
  border: 1px solid color-mix(in srgb, var(--band-muted) 35%, transparent);
  border-radius: 999px;
  font-family: var(--font-formule);
  font-size: clamp(1rem, 1.8vw, 1.15rem);
  color: var(--band-muted);
}
.reaction__arrow { font-family: var(--font-testo); }
.reaction__energy { font-family: var(--font-testo); font-size: 0.85em; font-style: italic; }


/* 9. RECENSIONI ------------------------------------------------------------ */

.reviews {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.5rem, 3vw, 2.5rem);
}
.review {
  margin: 0;
  padding: 0.25rem 0 0.25rem 1.5rem;
  border-left: 3px solid var(--azzurro-chiaro);
}
.review--placeholder { border-left-style: dashed; border-left-color: var(--border); }
.review blockquote { margin: 0 0 1.25rem; }
.review blockquote p { font-size: 1.05rem; color: var(--heading); }
.review figcaption { font-size: 0.92rem; color: var(--text-muted); }
.review figcaption strong { display: block; color: var(--heading); font-family: var(--font-titoli); }

.embed-slot {
  margin-top: 2.5rem;
  padding: 1.5rem;
  border: 1.5px dashed var(--border);
  border-radius: var(--radius);
  font-size: 0.95rem;
  color: var(--text-muted);
  text-align: center;
}

@media (max-width: 880px) {
  .reviews { grid-template-columns: 1fr; }
}


/* 10. INVITO AL CONTATTO --------------------------------------------------- */

.cta-box {
  position: relative;
  overflow: hidden;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 2rem;
  align-items: center;
  padding: clamp(2rem, 5vw, 3.5rem);
  border-radius: var(--radius-lg);
  background: var(--surface-didattica);
}
.cta-box h2 { margin-bottom: 0.4rem; position: relative; }
.cta-box p { margin: 0; color: var(--heading); position: relative; }
.cta-box .btn { position: relative; }
.cta-box__deco {
  position: absolute;
  right: -50px;
  bottom: -70px;
  width: 300px;
  transform: rotate(-14deg);
  color: var(--heading);
  opacity: 0.08;
  pointer-events: none;
}

@media (max-width: 720px) {
  .cta-box { grid-template-columns: 1fr; }
  .cta-box__deco { right: -110px; bottom: -90px; }
}


/* 11. PAGINE INTERNE: INTESTAZIONE ----------------------------------------- */

.page-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(3.25rem, 7vw, 5.5rem) clamp(2.75rem, 5vw, 4rem);
  background: var(--surface-soft);
  border-bottom: 1px solid var(--border);
}
.page-hero__pattern {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  color: var(--deco);
  opacity: 0.1;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to left, #000 0%, transparent 60%);
  mask-image: linear-gradient(to left, #000 0%, transparent 60%);
}
.page-hero .container { position: relative; }
.page-hero h1 { max-width: 20ch; }
.page-hero .lead { max-width: 40rem; margin-bottom: 0; }

.anchor-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
}
.anchor-nav a {
  display: inline-block;
  padding: 0.45rem 1rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  font-family: var(--font-titoli);
  font-weight: 600;
  font-size: 0.93rem;
  color: var(--heading);
  text-decoration: none;
}
.anchor-nav a:hover { border-color: var(--heading); }


/* 12. CHI SONO ------------------------------------------------------------- */

.about {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(2.5rem, 6vw, 5rem);
  align-items: start;
}
.about__media { position: relative; max-width: 440px; }

.photo {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4 / 5;
  border-radius: var(--radius-lg);
  background: var(--surface-didattica);
}
.photo img { width: 100%; height: 100%; object-fit: cover; }
.photo__placeholder {
  position: absolute;
  inset: 14px;
  display: grid;
  place-items: center;
  border: 1.5px dashed color-mix(in srgb, var(--heading) 30%, transparent);
  border-radius: calc(var(--radius-lg) - 10px);
  font-size: 0.92rem;
  color: var(--heading);
  text-align: center;
  padding: 1rem;
}

/* Tessera "elemento chimico" con i dati principali */
.element {
  position: absolute;
  right: -1.5rem;
  bottom: -1.75rem;
  width: 196px;
  padding: 0.85rem 1.1rem 1rem;
  border: 2px solid var(--heading);
  border-radius: 6px;
  background: var(--surface);
  color: var(--heading);
  font-family: var(--font-titoli);
}
.element__top { display: flex; justify-content: space-between; align-items: flex-start; gap: 0.5rem; }
.element__number { font-size: 1.6rem; font-weight: 800; line-height: 1; }
.element__number-label { font-family: var(--font-testo); font-size: 0.68rem; line-height: 1.25; text-align: right; color: var(--text-muted); max-width: 9ch; }
.element__symbol { display: block; margin: 0.35rem 0 0.15rem; font-size: 3.4rem; font-weight: 800; line-height: 1; letter-spacing: -0.04em; color: var(--accent); }
.element__name { display: block; font-size: 0.95rem; font-weight: 700; line-height: 1.2; }
.element__meta { display: block; margin-top: 0.4rem; font-family: var(--font-testo); font-size: 0.72rem; line-height: 1.35; color: var(--text-muted); }

@media (max-width: 880px) {
  .about { grid-template-columns: 1fr; }
  .about__media { margin-bottom: 2rem; }
  .element { right: 0.75rem; }
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
  gap: clamp(2rem, 6vw, 5rem);
  align-items: start;
}
.split .section-head { position: sticky; top: calc(var(--header-h) + 2rem); }
@media (max-width: 880px) {
  .split { grid-template-columns: 1fr; gap: 0; }
  .split .section-head { position: static; }
}

.timeline {
  position: relative;
  max-width: 760px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.timeline__item { position: relative; padding: 0 0 2.25rem 3rem; }
.timeline__item:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 11px;
  top: 27px;
  bottom: 3px;
  width: 2px;
  background: color-mix(in srgb, var(--link) 30%, transparent);
}
.timeline__item:last-child { padding-bottom: 0; }
.timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 3px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 3px solid var(--link);
  background: var(--bg);
}
.section--soft .timeline__item::before { background: var(--surface-soft); }
.timeline__item--accent::before { border-color: var(--accent); background: var(--accent) !important; }
.timeline__date { font-family: var(--font-titoli); font-weight: 700; font-size: 0.95rem; color: var(--accent); }
.timeline__item h3 { font-size: 1.15rem; margin: 0.2rem 0 0.3rem; }
.timeline__item p { margin: 0; color: var(--text-muted); }

.values {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.5rem, 4vw, 3rem);
}
.value h3 { display: flex; align-items: center; gap: 0.65rem; }
.value__icon { width: 30px; height: 30px; color: var(--accent); flex: none; }

@media (max-width: 820px) {
  .values { grid-template-columns: 1fr; }
}


/* 13. SERVIZI -------------------------------------------------------------- */

.levels {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}
.level {
  padding: 1.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}
.level h3 { margin-bottom: 0.2rem; }
.level__sub { display: block; margin-bottom: 1rem; font-size: 0.9rem; color: var(--text-muted); }
.level p { margin: 0; }

@media (max-width: 880px) {
  .levels { grid-template-columns: 1fr; }
}

.subject-detail {
  --c: var(--c-matematica);
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: start;
  padding-block: clamp(3rem, 6vw, 4.5rem);
  border-top: 1px solid var(--border);
}
.subject-detail:first-of-type { border-top: 0; padding-top: 0; }
.subject-detail--fisica  { --c: var(--c-fisica); }
.subject-detail--chimica { --c: var(--c-chimica); }
.subject-detail__intro { position: sticky; top: calc(var(--header-h) + 2rem); }
.subject-detail__icon { width: 52px; height: 52px; color: var(--c); margin-bottom: 1.25rem; }
.subject-detail h2 { display: flex; align-items: baseline; gap: 0.75rem; flex-wrap: wrap; }
.subject-detail h2 .formula-hint {
  font-family: var(--font-formule);
  font-style: italic;
  font-weight: 400;
  font-size: 1.05rem;
  letter-spacing: 0;
  color: var(--text-muted);
}
.subject-detail--chimica h2 .formula-hint { font-style: normal; }

.topics { display: grid; gap: 1rem; }
.topic-group {
  padding: 1.25rem 1.4rem;
  border-left: 3px solid var(--c);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--surface);
}
.topic-group h3 { font-size: 1rem; margin-bottom: 0.75rem; }
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.tags li {
  padding: 0.28rem 0.75rem;
  border-radius: 999px;
  background: var(--surface-soft);
  font-size: 0.9rem;
  color: var(--heading);
}

@media (max-width: 880px) {
  .subject-detail { grid-template-columns: 1fr; }
  .subject-detail__intro { position: static; }
}

.features {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2.25rem clamp(2rem, 5vw, 4rem);
}
.feature { display: grid; grid-template-columns: 40px minmax(0, 1fr); gap: 1rem; }
.feature__icon { width: 32px; height: 32px; margin-top: 0.15rem; color: var(--accent); }
.feature h3 { font-size: 1.15rem; margin-bottom: 0.35rem; }
.feature p { margin: 0; }

@media (max-width: 760px) {
  .features { grid-template-columns: 1fr; }
}

.modes {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: 0;
  border-top: 1px solid var(--border);
}
.modes > div { padding: 1.5rem 1.5rem 1.5rem 0; border-bottom: 1px solid var(--border); }
.modes dt { font-family: var(--font-titoli); font-weight: 700; font-size: 1.1rem; color: var(--heading); margin-bottom: 0.3rem; }
.modes dd { margin: 0; }

@media (max-width: 760px) {
  .modes { grid-template-columns: 1fr; }
}

.faq { max-width: 820px; }
.faq details { border-bottom: 1px solid var(--border); }
.faq details:first-child { border-top: 1px solid var(--border); }
.faq summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1.3rem 0;
  font-family: var(--font-titoli);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--heading);
  cursor: pointer;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  flex: none;
  font-size: 1.6rem;
  font-weight: 500;
  line-height: 1;
  color: var(--link);
  transition: transform 0.2s ease;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { margin: 0 0 1.4rem; }


/* 14. CONTATTI E MODULO ---------------------------------------------------- */

.contact {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(0, 0.85fr);
  gap: clamp(2rem, 5vw, 4rem);
  align-items: start;
}

.form-card {
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
}
.form-card h2 { font-size: 1.6rem; }

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}
.field { display: flex; flex-direction: column; gap: 0.4rem; margin: 0; padding: 0; border: 0; min-width: 0; }
.field--full { grid-column: 1 / -1; }
.field label,
.field legend {
  padding: 0;
  font-family: var(--font-titoli);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--heading);
}
.field legend { margin-bottom: 0.4rem; }
.field .optional { font-family: var(--font-testo); font-weight: 400; color: var(--text-muted); font-size: 0.85rem; }

.input {
  width: 100%;
  padding: 0.8rem 0.95rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  font: inherit;
  font-size: 1rem;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.input::placeholder { color: var(--text-muted); opacity: 0.85; }
.input:focus {
  outline: none;
  border-color: var(--link);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--link) 22%, transparent);
}
select.input {
  appearance: none;
  padding-right: 2.5rem;
  background-image: linear-gradient(45deg, transparent 50%, currentColor 50%), linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: calc(100% - 20px) 50%, calc(100% - 14px) 50%;
  background-size: 6px 6px;
  background-repeat: no-repeat;
}
textarea.input { min-height: 150px; resize: vertical; line-height: 1.6; }

.choices { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.choice { position: relative; }
.choice input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.choice span {
  display: inline-block;
  padding: 0.6rem 1.1rem;
  border: 1.5px solid var(--border);
  border-radius: 999px;
  font-size: 0.97rem;
  color: var(--heading);
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}
.choice input:checked + span { background: var(--btn-bg); border-color: var(--btn-bg); color: var(--btn-text); }
.choice input:focus-visible + span { outline: 3px solid var(--link); outline-offset: 2px; }

.checkbox { display: flex; gap: 0.7rem; align-items: flex-start; font-size: 0.93rem; line-height: 1.5; }
.checkbox input { width: 20px; height: 20px; margin: 0.1rem 0 0; accent-color: var(--btn-bg); flex: none; }

.form-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem; margin-top: 0.5rem; }

.form-status { font-size: 0.95rem; margin: 0; }
.form-status:empty { display: none; }
.form-status.is-success,
.form-status.is-error,
.form-status.is-info {
  display: block;
  width: 100%;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface-soft);
  color: var(--heading);
}
.form-status.is-success { border-color: var(--accent); }
.form-status.is-error   { border-color: var(--link); }

@media (max-width: 640px) {
  .form-grid { grid-template-columns: 1fr; }
}

.contact-info h2 { font-size: 1.35rem; margin-bottom: 1.25rem; }
.contact-list { list-style: none; margin: 0 0 2rem; padding: 0; display: grid; gap: 1.25rem; }
.contact-list li { display: grid; grid-template-columns: 40px minmax(0, 1fr); gap: 0.9rem; align-items: start; }
.contact-list__icon {
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--surface-didattica);
  color: var(--heading);
}
.contact-list__icon svg { width: 20px; height: 20px; }
.contact-list strong { display: block; font-family: var(--font-titoli); color: var(--heading); font-size: 0.95rem; }
.contact-list span, .contact-list a { font-size: 0.98rem; overflow-wrap: anywhere; }

.reassure {
  padding: 1.25rem 1.4rem;
  border-radius: var(--radius);
  background: var(--surface-didattica);
  color: var(--heading);
  font-size: 0.97rem;
}
.reassure p { margin: 0; }

@media (max-width: 880px) {
  .contact { grid-template-columns: 1fr; }
}


/* 15. TESTI LUNGHI (privacy, futuri articoli) ------------------------------ */

.prose { max-width: 720px; }
.prose h2 { font-size: 1.6rem; margin-top: 2.25em; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin-top: 1.75em; }
.prose ul, .prose ol { padding-left: 1.25em; margin: 0 0 1.2em; }
.prose li { margin-bottom: 0.4em; }
.prose blockquote {
  margin: 1.75em 0;
  padding-left: 1.25rem;
  border-left: 3px solid var(--accent);
  font-size: 1.15rem;
  color: var(--heading);
}
.prose .formula-block {
  margin: 1.75em 0;
  padding: 1.1rem 1.4rem;
  border-radius: var(--radius-sm);
  background: var(--surface-soft);
  font-family: var(--font-formule);
  font-size: 1.2rem;
  color: var(--heading);
  text-align: center;
  overflow-x: auto;
}
.prose figure { margin: 2em 0; }
.prose figcaption { margin-top: 0.6rem; font-size: 0.9rem; color: var(--text-muted); }

.article-meta { margin-top: 1rem; font-size: 0.95rem; color: var(--text-muted); }


/* 16. FOOTER --------------------------------------------------------------- */

.site-footer {
  position: relative;
  overflow: hidden;
  padding-block: 4.5rem 2rem;
  background: var(--band-bg);
  color: var(--band-muted);
  font-size: 0.97rem;
}
.site-footer__deco {
  position: absolute;
  right: -40px;
  bottom: -30px;
  width: 340px;
  color: var(--band-muted);
  opacity: 0.08;
  pointer-events: none;
}
.footer-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr) minmax(0, 1fr);
  gap: 2.5rem;
}
.site-footer .brand,
.site-footer .brand:hover { color: var(--band-text); }
.site-footer .brand__tag { color: var(--band-muted); }
.site-footer .brand__mark .brand__dot { fill: var(--band-muted); }
.footer-about { margin-top: 1.25rem; max-width: 34ch; }
.footer-title {
  margin: 0 0 1rem;
  font-family: var(--font-titoli);
  font-weight: 700;
  font-size: 1rem;
  color: var(--band-text);
}
.footer-links { display: grid; gap: 0.55rem; list-style: none; margin: 0; padding: 0; }
.site-footer a { color: var(--band-muted); text-decoration: none; }
.site-footer a:hover { color: var(--band-text); text-decoration: underline; }
.footer-bottom {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  margin-top: 3.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid color-mix(in srgb, var(--band-muted) 20%, transparent);
  font-size: 0.87rem;
}
.footer-bottom p { margin: 0; max-width: none; }

@media (max-width: 760px) {
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
}


/* 17. UTILITY E ACCESSIBILITÀ ---------------------------------------------- */

/* Segnaposto: evidenzia i testi da completare. Quando hai finito,
   puoi togliere la classe "ph" dagli elementi (o lasciare questa regola). */
.ph {
  padding: 0 0.15em;
  border-radius: 3px;
  background: color-mix(in srgb, var(--accent) 13%, transparent);
  box-shadow: inset 0 -1.5px 0 color-mix(in srgb, var(--accent) 60%, transparent);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 100;
  padding: 0.75rem 1.1rem;
  border-radius: var(--radius-sm);
  background: var(--btn-bg);
  color: var(--btn-text);
  font-weight: 600;
  text-decoration: none;
}
.skip-link:focus { top: 1rem; color: var(--btn-text); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

.container.prose { max-width: var(--container); }
.container.prose > * { max-width: 720px; }