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

:root {
  --bg:        #0b0e14;
  --surface:   #13181f;
  --surface2:  #1a2130;
  --border:    #232d3d;
  --accent:    #f0c040;
  --accent2:   #3dd6f5;
  --accent3:   #f05a70;
  --text:      #e2e8f0;
  --text-muted:#7a8fa6;
  --font-serif:'DM Serif Display', serif;
  --font-mono: 'Space Mono', monospace;
  --font-body: 'DM Sans', sans-serif;
  --radius:    12px;
  --radius-lg: 20px;
}

html { scroll-behavior: smooth; }

/* ===== ACESSIBILIDADE ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  background: var(--accent);
  color: var(--bg);
  padding: 10px 20px;
  font-family: var(--font-mono);
  font-size: .85rem;
  font-weight: bold;
  z-index: 9999;
  border-radius: 0 0 8px 0;
  text-decoration: none;
  transition: top .15s;
}
.skip-link:focus { top: 0; outline: 3px solid var(--accent2); outline-offset: 2px; }

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  overflow-x: hidden;
}

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding: 80px 6vw 60px;
  gap: 40px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.grid-lines {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(61,214,245,.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(61,214,245,.07) 1px, transparent 1px);
  background-size: 60px 60px;
}

.moving-dot {
  position: absolute;
  top: 50%;
  width: 18px;
  height: 18px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 30px var(--accent), 0 0 60px var(--accent);
  transform: translateY(-50%);
  animation: moveDot 4s ease-in-out infinite alternate;
}

/* Trail effect */
.moving-dot::after {
  content: '';
  position: absolute;
  top: 50%;
  right: 18px;
  height: 2px;
  width: 120px;
  background: linear-gradient(to left, var(--accent), transparent);
  transform: translateY(-50%);
}

@keyframes moveDot {
  0%   { left: 5%; }
  100% { left: 80%; }
}

.hero-content { position: relative; z-index: 1; }

.hero-label {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .15em;
  text-transform: uppercase;
  color: var(--accent2);
  display: block;
  margin-bottom: 20px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(3rem, 7vw, 6rem);
  line-height: 1.05;
  color: var(--text);
  margin-bottom: 24px;
}

.hero-title em {
  font-style: italic;
  color: var(--accent);
}

.hero-sub {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 440px;
  margin-bottom: 40px;
  line-height: 1.8;
}

.cta-btn {
  display: inline-block;
  background: var(--accent);
  color: #0b0e14;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: .9rem;
  padding: 14px 32px;
  text-decoration: none;
  border-radius: 4px;
  transition: transform .2s, box-shadow .2s;
  letter-spacing: .05em;
}

.cta-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(240,192,64,.35);
}

.hero-formula {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.formula-big {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4vw, 3.5rem);
  color: var(--accent2);
  background: rgba(61,214,245,.06);
  border: 1px solid rgba(61,214,245,.2);
  padding: 30px 40px;
  border-radius: var(--radius-lg);
  text-shadow: 0 0 40px rgba(61,214,245,.4);
  white-space: nowrap;
}

/* ===== SUMÁRIO ===== */
.sumario {
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 20px 6vw;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
}

.sumario-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  overflow-x: auto;
  scrollbar-width: none;
}

.sumario-inner::-webkit-scrollbar { display: none; }

.sumario-title {
  font-family: var(--font-mono);
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: .15em;
  color: var(--text-muted);
  white-space: nowrap;
}

.sumario-header {
  display: flex;
  align-items: center;
  gap: 12px;
  white-space: nowrap;
  flex-shrink: 0;
}

.sumario-logo-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  transition: opacity .2s;
}

.sumario-logo-link:hover {
  opacity: 0.7;
}

.sumario-logo {
  height: 32px;
  width: auto;
  display: block;
}

.sumario-list {
  display: flex;
  gap: 6px;
  list-style: none;
  padding: 0;
}

.sumario-list a {
  display: block;
  padding: 6px 14px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: .82rem;
  font-family: var(--font-mono);
  border-radius: 4px;
  white-space: nowrap;
  transition: background .15s, color .15s;
}

.sumario-list a:hover {
  background: rgba(240,192,64,.12);
  color: var(--accent);
}

/* ===== MAIN ===== */
.main { max-width: 860px; margin: 0 auto; padding: 40px 24px 80px; }

/* ===== TOPIC ===== */
.topic {
  margin-bottom: 80px;
  animation: fadeUp .5s ease both;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

.topic-header {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 28px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.topic-num {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  color: var(--accent);
  opacity: .4;
  line-height: 1;
  min-width: 60px;
}

.topic-header h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  color: var(--text);
  line-height: 1.2;
}

.topic-body p {
  color: var(--text-muted);
  margin-bottom: 18px;
  font-size: 1rem;
  line-height: 1.8;
}

.topic-body p strong { color: var(--text); }
.topic-body p em { color: var(--accent2); }

/* ===== HIGHLIGHT BOX ===== */
.highlight-box {
  display: flex;
  gap: 16px;
  background: rgba(61,214,245,.07);
  border-left: 3px solid var(--accent2);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 16px 20px;
  margin: 20px 0;
}

.hb-icon { font-size: 1.4rem; flex-shrink: 0; margin-top: 2px; }

.highlight-box p {
  color: var(--text);
  margin: 0;
  font-size: .95rem;
}

/* ===== CONCEPT CARD ===== */
.concept-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 20px 0;
}

.concept-card h4 {
  font-family: var(--font-mono);
  font-size: .82rem;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--accent);
  margin-bottom: 12px;
}

.concept-card ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.concept-card li {
  color: var(--text-muted);
  padding-left: 20px;
  position: relative;
  font-size: .95rem;
}

.concept-card li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-family: var(--font-mono);
}

.concept-card li strong { color: var(--text); }

/* ===== FORMULA BOX ===== */
.formula-box {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 24px;
  margin: 20px 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.formula-box.large { padding: 24px 32px; text-align: center; }

.formula-label {
  font-family: var(--font-mono);
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: .15em;
  color: var(--text-muted);
}

.formula-tex {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  color: var(--accent2);
}

.formula-tex.big {
  font-size: 2rem;
  color: var(--accent);
  text-shadow: 0 0 30px rgba(240,192,64,.3);
}

.formula-unit {
  font-size: .8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

/* ===== CONVERTER ===== */
.converter-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 20px 0;
}

.converter-box h4 {
  font-family: var(--font-mono);
  font-size: .82rem;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent);
  margin-bottom: 14px;
}

.converter-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.conv-input {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: .95rem;
  padding: 8px 14px;
  border-radius: 6px;
  width: 130px;
  transition: border-color .2s;
}

.conv-input:focus { outline: none; border-color: var(--accent2); }
.conv-input[readonly] { color: var(--accent2); background: rgba(61,214,245,.05); }

.conv-arrow { color: var(--accent); font-size: 1.2rem; font-family: var(--font-mono); }

/* ===== CALCULATOR ===== */
.calc-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  margin: 24px 0;
}

.calc-box h4 {
  font-family: var(--font-mono);
  font-size: .82rem;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent);
  margin-bottom: 6px;
}

.calc-hint { font-size: .85rem; color: var(--text-muted); margin-bottom: 16px; }

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.calc-grid label {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: .85rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.calc-inp {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: .9rem;
  padding: 8px 12px;
  border-radius: 6px;
  transition: border-color .2s;
  width: 100%;
}

.calc-inp:focus { outline: none; border-color: var(--accent); }

.calc-btn {
  background: var(--accent);
  color: #0b0e14;
  border: none;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: .85rem;
  padding: 10px 24px;
  border-radius: 6px;
  cursor: pointer;
  letter-spacing: .06em;
  transition: transform .15s, box-shadow .15s;
}

.calc-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(240,192,64,.3);
}

.calc-result {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: .95rem;
  color: var(--accent2);
  min-height: 24px;
}

/* ===== GRAPHS ===== */
.graphs-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin: 20px 0;
}

.graph-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
}

.graph-card h4 {
  font-family: var(--font-mono);
  font-size: .75rem;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent);
  margin-bottom: 12px;
}

.graph-card canvas {
  display: block;
  width: 100%;
  border-radius: 6px;
}

.graph-card ul {
  list-style: none;
  margin-top: 12px;
}

.graph-card li {
  font-size: .8rem;
  color: var(--text-muted);
  padding: 2px 0 2px 14px;
  position: relative;
}

.graph-card li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--accent2);
}

.graph-controls {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin: 16px 0;
}

.graph-controls h4 {
  font-family: var(--font-mono);
  font-size: .8rem;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent);
  margin-bottom: 14px;
}

.slider-row {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 10px;
}

.slider-row label {
  font-family: var(--font-mono);
  font-size: .85rem;
  color: var(--text-muted);
  min-width: 90px;
}

.slider {
  flex: 1;
  accent-color: var(--accent);
  height: 4px;
  cursor: pointer;
}

/* ===== CLASSIFY GRID ===== */
.classify-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin: 20px 0;
}

.classify-card {
  border-radius: var(--radius);
  padding: 20px 22px;
  border: 1px solid;
}

.classify-card.positive {
  background: rgba(61,214,245,.06);
  border-color: rgba(61,214,245,.25);
}

.classify-card.negative {
  background: rgba(240,90,112,.06);
  border-color: rgba(240,90,112,.25);
}

.cc-icon {
  font-size: 2rem;
  margin-bottom: 8px;
  font-family: var(--font-mono);
}

.classify-card.positive .cc-icon { color: var(--accent2); }
.classify-card.negative .cc-icon { color: var(--accent3); }

.classify-card h4 {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.classify-card p {
  font-size: .88rem;
  color: var(--text-muted);
  margin-bottom: 6px !important;
}

.cc-eq {
  font-family: var(--font-mono) !important;
  font-size: .85rem !important;
  color: var(--text) !important;
  margin-top: 8px !important;
}

/* ===== EXAMPLE BOX ===== */
.example-box {
  background: rgba(240,192,64,.06);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 16px 20px;
  margin: 20px 0;
}

.example-box h4 {
  font-family: var(--font-mono);
  font-size: .75rem;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--accent);
  margin-bottom: 10px;
}

.example-box p {
  font-size: .92rem;
  color: var(--text-muted);
  margin-bottom: 6px !important;
  font-family: var(--font-mono);
}

.example-box p strong { color: var(--accent) !important; }

/* ===== QUIZ ===== */
.quiz-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  margin-top: 36px;
}

.quiz-title {
  font-family: var(--font-mono);
  font-size: .7rem;
  text-transform: uppercase;
  letter-spacing: .15em;
  color: var(--accent);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.quiz-title::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 2px;
  background: var(--accent);
}

.question-block {
  margin-bottom: 28px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--border);
}

.question-block:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.question-text {
  font-size: .95rem;
  color: var(--text);
  margin-bottom: 14px;
  line-height: 1.7;
}

.question-num {
  font-family: var(--font-mono);
  font-size: .75rem;
  color: var(--text-muted);
  display: block;
  margin-bottom: 6px;
  letter-spacing: .1em;
}

/* Objective questions */
.options-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.option-btn {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: .9rem;
  padding: 10px 16px;
  border-radius: 8px;
  cursor: pointer;
  text-align: left;
  transition: border-color .15s, background .15s, color .15s;
  display: flex;
  align-items: center;
  gap: 10px;
}

.option-btn:hover:not(:disabled) {
  border-color: var(--accent2);
  background: rgba(61,214,245,.05);
  color: var(--text);
}

.option-btn.correct {
  border-color: #22c55e;
  background: rgba(34,197,94,.1);
  color: #22c55e;
}

.option-btn.wrong {
  border-color: var(--accent3);
  background: rgba(240,90,112,.1);
  color: var(--accent3);
}

.option-btn:disabled { cursor: default; }

.opt-letter {
  font-family: var(--font-mono);
  font-size: .75rem;
  font-weight: 700;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid currentColor;
  flex-shrink: 0;
  opacity: .7;
}

/* Numeric questions */
.numeric-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.numeric-inp {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 1rem;
  padding: 9px 14px;
  border-radius: 8px;
  width: 140px;
  transition: border-color .2s;
}

.numeric-inp:focus { outline: none; border-color: var(--accent2); }

.numeric-unit {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: var(--text-muted);
}

.submit-btn {
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: .78rem;
  padding: 9px 18px;
  border-radius: 6px;
  cursor: pointer;
  letter-spacing: .06em;
  transition: background .15s, color .15s;
}

.submit-btn:hover { background: var(--accent); color: #0b0e14; }

.feedback {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: .85rem;
  padding: 10px 14px;
  border-radius: 6px;
  display: none;
}

.feedback.show { display: block; }
.feedback.correct { color: #22c55e; background: rgba(34,197,94,.1); border: 1px solid rgba(34,197,94,.3); }
.feedback.wrong   { color: var(--accent3); background: rgba(240,90,112,.1); border: 1px solid rgba(240,90,112,.3); }

/* ===== SCORE ===== */
.score-section {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 80px 24px;
  text-align: center;
}

.score-inner { max-width: 500px; margin: 0 auto; }

.score-inner h2 {
  font-family: var(--font-serif);
  font-size: 2rem;
  margin-bottom: 30px;
}

.score-display {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 20px;
}

#score-num {
  font-family: var(--font-mono);
  font-size: 5rem;
  color: var(--accent);
  line-height: 1;
}

.score-sep {
  font-family: var(--font-mono);
  font-size: 3rem;
  color: var(--text-muted);
}

#score-total {
  font-family: var(--font-mono);
  font-size: 5rem;
  color: var(--text-muted);
  line-height: 1;
}

#score-msg {
  color: var(--text-muted);
  margin-bottom: 24px;
  font-size: .95rem;
}

.reset-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: .8rem;
  padding: 10px 22px;
  border-radius: 6px;
  cursor: pointer;
  transition: border-color .2s, color .2s;
}

.reset-btn:hover { border-color: var(--accent3); color: var(--accent3); }

.report-actions {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.report-hint {
  font-size: .8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  font-family: var(--font-mono);
  letter-spacing: .05em;
}

.report-btns {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

.report-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: .75rem;
  padding: 8px 16px;
  border-radius: 6px;
  cursor: pointer;
  transition: border-color .2s, color .2s, background .2s;
}

.report-btn:hover {
  border-color: var(--accent2);
  color: var(--accent2);
  background: rgba(61,214,245,.06);
}

.report-name { margin-bottom: 20px; }

.name-input {
  display: block; width: 100%; max-width: 320px; margin: 6px auto 0;
  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
  color: var(--text); font-family: var(--font-body); font-size: .9rem;
  padding: 9px 14px; outline: none; transition: border-color .2s;
}
.name-input:focus { border-color: var(--accent); }

/* ===== FOOTER ===== */
.footer {
  padding: 24px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: .7rem;
  color: var(--text-muted);
  letter-spacing: .1em;
  text-transform: uppercase;
  border-top: 1px solid var(--border);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero {
    grid-template-columns: 1fr;
    padding: 80px 24px 50px;
  }

  .hero-formula { display: none; }

  .graphs-container,
  .classify-grid,
  .calc-grid { grid-template-columns: 1fr; }

  .sumario { padding: 14px 16px; }

  .quiz-section { padding: 20px 18px; }

  #score-num, #score-total { font-size: 3.5rem; }
}

/* ===== SCROLL ANIMATION ===== */
.topic { opacity: 0; transform: translateY(30px); transition: opacity .6s ease, transform .6s ease; }
.topic.visible { opacity: 1; transform: translateY(0); }