/* ========================================= */
/* Rumus Gerak V2 */
/* ========================================= */

.rumus-nav {
  position: sticky;
  top: 0;
  z-index: 999;
  padding: 14px 0;

  background: rgba(255, 255, 255, 0.06);
  border-bottom: 1px solid rgba(255, 255, 255, 0.10);
  backdrop-filter: blur(16px);
}

body.light .rumus-nav {
  background: rgba(255, 255, 255, 0.75);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.rumus-nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-back {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  font-weight: 800;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.85);
}

body.light .nav-back {
  color: var(--text);
}

.nav-back i {
  font-size: 20px;
  color: var(--red-light);
}

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

.nav-title h2 {
  font-family: "Patrick Hand", cursive;
  font-size: 34px;
  margin: 0;
  color: var(--red-light);
  text-shadow: 0 0 16px rgba(176, 0, 0, 0.55);
}

.nav-title p {
  margin: 0;
  font-size: 12px;
  opacity: 0.75;
  color: rgba(255, 255, 255, 0.75);
}

body.light .nav-title p {
  color: rgba(0, 0, 0, 0.65);
}

.nav-actions .nav-btn {
  border: none;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  cursor: pointer;

  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: white;
  font-size: 16px;
}

body.light .nav-actions .nav-btn {
  background: rgba(176, 0, 0, 0.08);
  border: 1px solid rgba(0, 0, 0, 0.08);
  color: var(--text);
}

/* HERO */
.rumus-hero {
  padding: 85px 0 60px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 35px;
  align-items: center;
}

.hero-text h1 {
  font-family: "Patrick Hand", cursive;
  font-size: 72px;
  color: white;
  text-shadow: 0 0 25px rgba(176, 0, 0, 0.35);
}

body.light .hero-text h1 {
  color: var(--text);
}

.hero-text p {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.75);
}

body.light .hero-text p {
  color: rgba(0, 0, 0, 0.65);
}

.hero-badges {
  margin-top: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-badges span {
  padding: 7px 16px;
  border-radius: 16px;
  font-size: 13px;
  font-weight: 800;

  background: rgba(176, 0, 0, 0.12);
  border: 1px solid rgba(176, 0, 0, 0.25);
  color: var(--red-light);
}

/* HERO CARD */
.hero-card {
  padding: 28px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  backdrop-filter: blur(16px);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.45);
}

body.light .hero-card {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

.hero-card h3 {
  font-family: "Patrick Hand", cursive;
  font-size: 34px;
  margin-bottom: 18px;
  color: white;
}

body.light .hero-card h3 {
  color: var(--text);
}

.formula-mini {
  padding: 12px 14px;
  border-radius: 18px;
  margin-bottom: 12px;

  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.10);
}

body.light .formula-mini {
  background: rgba(176, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

.formula-mini p {
  margin: 0;
  font-size: 16px;
  color: white;
}

body.light .formula-mini p {
  color: var(--text);
}

.formula-mini small {
  opacity: 0.75;
}

.hero-btn {
  display: block;
  margin-top: 18px;
  text-align: center;
  padding: 12px;
  border-radius: 18px;
  font-weight: 800;
  text-decoration: none;

  background: linear-gradient(90deg, var(--red-dark), var(--red-light));
  color: white;
  transition: 0.25s ease;
}

.hero-btn:hover {
  transform: translateY(-4px);
  box-shadow: 0 0 18px rgba(176, 0, 0, 0.35);
}

/* CONTENT CARDS */
.info-card {
  padding: 28px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.70);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

body.dark .info-card {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.55);
}

.info-card h4 {
  font-family: "Patrick Hand", cursive;
  font-size: 34px;
  margin-bottom: 10px;
}

.info-card p {
  font-size: 14px;
  line-height: 1.8;
  opacity: 0.85;
}

.info-formula {
  margin-top: 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.info-formula span {
  padding: 8px 14px;
  border-radius: 18px;
  font-size: 13px;
  font-weight: 800;

  background: rgba(176, 0, 0, 0.12);
  border: 1px solid rgba(176, 0, 0, 0.25);
  color: var(--red-light);
}

/* Kalkulator */
.calc-tabs {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-top: 25px;
  margin-bottom: 25px;
}

.tab-btn {
  padding: 10px 22px;
  border-radius: 18px;
  border: none;
  font-weight: 900;
  cursor: pointer;
  transition: 0.25s ease;

  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.85);
}

/* Responsive Tabs / Filter Fix */
.calc-tabs {
  display: flex;
  justify-content: center;
  flex-wrap: wrap; /* INI KUNCI */
  gap: 10px;
  margin-top: 25px;
}

.tab-btn {
  flex: 1 1 auto;
  min-width: 140px; /* biar ga terlalu kecil */
  text-align: center;
  padding: 12px 18px;
  border-radius: 18px;
  font-weight: 900;
  cursor: pointer;
  transition: 0.25s ease;
}

@media (max-width: 576px) {
  .tab-btn {
    min-width: 48%;
    font-size: 14px;
    padding: 10px 12px;
  }
}

body.light .tab-btn {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid rgba(0, 0, 0, 0.08);
  color: var(--text);
}

.tab-btn.active {
  background: linear-gradient(90deg, var(--red-dark), var(--red-light));
  color: white;
  box-shadow: 0 0 18px rgba(176, 0, 0, 0.35);
}

.calc-box {
  display: none;
  padding: 35px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.70);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

body.dark .calc-box {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 14px 35px rgba(0, 0, 0,  0.55);
}

.calc-box.active {
  display: block;
}

.calc-title {
  font-family: "Patrick Hand", cursive;
  font-size: 50px;
  text-align: center;
  margin-bottom: 5px;
}

.calc-sub {
  text-align: center;
  font-size: 14px;
  opacity: 0.75;
}

.calc-label {
  font-weight: 800;
  font-size: 14px;
  margin-bottom: 6px;
  display: block;
}

.calc-input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 18px;
  outline: none;

  border: 1px solid rgba(0, 0, 0, 0.08);
  background: rgba(255, 255, 255, 0.85);
}

body.dark .calc-input {
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
  color: rgba(255, 255, 255, 0.9);
}

.calc-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.calc-btn {
  border: none;
  padding: 12px 22px;
  border-radius: 18px;
  font-weight: 900;
  cursor: pointer;
  transition: 0.25s ease;

  background: linear-gradient(90deg, var(--red-dark), var(--red-light));
  color: white;
}

.calc-btn:hover {
  transform: translateY(-4px);
  box-shadow: 0 0 18px rgba(176, 0, 0, 0.35);
}

.calc-btn.reset {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.85);
}

body.light .calc-btn.reset {
  background: rgba(0, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.08);
  color: var(--text);
}

.calc-result {
  padding: 16px;
  border-radius: 18px;
  text-align: center;

  background: rgba(176, 0, 0, 0.10);
  border: 1px solid rgba(176, 0, 0, 0.20);
}

.calc-result p {
  margin: 0;
  font-weight: 800;
}

/* VIDEO */
.video-frame {
  margin-top: 25px;
  padding: 35px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.70);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

body.dark .video-frame {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.55);
}

.video-placeholder {
  border-radius: 22px;
  padding: 70px 20px;
  text-align: center;

  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .video-placeholder {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.10);
}

.video-placeholder i {
  font-size: 55px;
  color: var(--red-light);
}

.video-placeholder p {
  margin-top: 12px;
  font-weight: 900;
  opacity: 0.8;
}

/* FOOTER */
.mini-footer {
  text-align: center;
  padding: 25px 0;
  opacity: 0.75;
  font-size: 13px;
}

/* RESPONSIVE */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .hero-text h1 {
    font-size: 60px;
    text-align: center;
  }

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

  .hero-badges {
    justify-content: center;
  }
}

@media (max-width: 520px) {
  .nav-title {
    display: none;
  }

  .hero-text h1 {
    font-size: 52px;
  }

  .calc-box {
    padding: 25px;
  }

  .calc-title {
    font-size: 42px;
  }
}

/* ========================================= */
/* Materi Detail Style */
/* ========================================= */

.content-card {
  padding: 35px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.70);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

body.dark .content-card {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.55);
}

.content-heading {
  font-family: "Patrick Hand", cursive;
  font-size: 48px;
  text-align: center;
  margin-bottom: 18px;
  text-shadow: 0 0 18px rgba(176, 0, 0, 0.35);
}

.symbol-table {
  margin-top: 20px;
  border-radius: 22px;
  overflow: hidden;
  border: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .symbol-table {
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.symbol-row {
  display: grid;
  grid-template-columns: 0.4fr 1.3fr 0.6fr;
  padding: 14px 18px;
  font-size: 14px;

  background: rgba(255, 255, 255, 0.55);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .symbol-row {
  background: rgba(255, 255, 255, 0.04);
  border-bottom: 1px solid rgba(255, 255, 255, 0.10);
}

.symbol-row:last-child {
  border-bottom: none;
}

.rumus-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.rumus-card {
  padding: 22px;
  border-radius: 22px;
  transition: 0.3s ease;

  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .rumus-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.10);
}

.rumus-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 0 22px rgba(176, 0, 0, 0.20);
}

.rumus-card h4 {
  font-family: "Patrick Hand", cursive;
  font-size: 30px;
  margin-bottom: 10px;
}

.rumus-formula {
  font-size: 20px;
  color: var(--red-light);
  text-shadow: 0 0 14px rgba(176, 0, 0, 0.35);
  margin: 0;
}

.note-box {
  padding: 16px 18px;
  border-radius: 18px;

  background: rgba(176, 0, 0, 0.10);
  border: 1px solid rgba(176, 0, 0, 0.20);
  font-size: 14px;
}

.example-box {
  padding: 22px;
  border-radius: 22px;

  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .example-box {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.10);
}

/* Responsive */
@media (max-width: 992px) {
  .rumus-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 520px) {
  .content-heading {
    font-size: 40px;
  }

  .rumus-grid {
    grid-template-columns: 1fr;
  }

  .symbol-row {
    grid-template-columns: 0.5fr 1fr 0.8fr;
    font-size: 13px;
  }

  .content-card {
    padding: 25px;
  }
}

/* ========================================= */
/* Quiz Section */
/* ========================================= */
.quiz-box {
  padding: 35px;
  border-radius: 26px;

  background: rgba(255, 255, 255, 0.70);
  border: 1px solid rgba(0, 0, 0, 0.08);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.08);
}

body.dark .quiz-box {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 14px 35px rgba(0, 0, 0, 0.55);
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 25px;
}

.quiz-header h3 {
  font-family: "Patrick Hand", cursive;
  font-size: 42px;
  margin: 0;
}

#quizScore {
  font-weight: 900;
  color: var(--red-light);
  text-shadow: 0 0 14px rgba(176, 0, 0, 0.35);
  margin: 0;
}

.quiz-question {
  padding: 22px;
  border-radius: 22px;
  margin-bottom: 16px;

  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(0, 0, 0, 0.06);
}

body.dark .quiz-question {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.10);
}

.quiz-question h4 {
  font-size: 16px;
  font-weight: 900;
  margin-bottom: 14px;
}

.quiz-options label {
  display: flex;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 16px;
  cursor: pointer;
  transition: 0.25s ease;
  font-weight: 700;

  background: rgba(255, 255, 255, 0.40);
  border: 1px solid rgba(0, 0, 0, 0.05);
  margin-bottom: 10px;
}

body.dark .quiz-options label {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.quiz-options label:hover {
  transform: translateX(6px);
  box-shadow: 0 0 18px rgba(176, 0, 0, 0.15);
}

.quiz-options input {
  margin-top: 3px;
}

.quiz-feedback {
  margin-top: 12px;
  font-size: 14px;
  font-weight: 800;
  padding: 10px 12px;
  border-radius: 16px;
  display: none;
}

.quiz-feedback.correct {
  display: block;
  background: rgba(0, 200, 100, 0.12);
  border: 1px solid rgba(0, 200, 100, 0.25);
}

.quiz-feedback.wrong {
  display: block;
  background: rgba(255, 0, 0, 0.12);
  border: 1px solid rgba(255, 0, 0, 0.25);
}

.quiz-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 25px;
}

.quiz-btn {
  border: none;
  padding: 12px 22px;
  border-radius: 18px;
  font-weight: 900;
  cursor: pointer;
  transition: 0.25s ease;

  background: linear-gradient(90deg, var(--red-dark), var(--red-light));
  color: white;
}

.quiz-btn:hover {
  transform: translateY(-4px);
  box-shadow: 0 0 18px rgba(176, 0, 0, 0.35);
}

.quiz-btn.reset {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.85);
}

body.light .quiz-btn.reset {
  background: rgba(0, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.08);
  color: var(--text);
}

.quiz-result {
  margin-top: 20px;
  padding: 16px;
  border-radius: 18px;
  text-align: center;
  font-weight: 900;

  background: rgba(176, 0, 0, 0.10);
  border: 1px solid rgba(176, 0, 0, 0.20);
}