:root {
  --bg: #f7f8f5;
  --surface: #ffffff;
  --surface-soft: #eef4f2;
  --ink: #18202f;
  --muted: #657084;
  --line: #dce3e0;
  --teal: #1b8a7f;
  --teal-dark: #12685f;
  --blue: #4f75c6;
  --amber: #c98a2e;
  --purple: #7560a8;
  --rose: #bc5d56;
  --shadow: 0 18px 50px rgba(25, 35, 48, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.5;
  overflow-x: hidden;
}

button,
input,
textarea {
  font: inherit;
  min-width: 0;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

a {
  color: inherit;
  text-decoration: none;
}

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

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 68px;
  padding: 12px 28px;
  background: rgba(247, 248, 245, 0.9);
  border-bottom: 1px solid rgba(220, 227, 224, 0.85);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  min-width: 0;
}

.brand-logo {
  width: 190px;
  height: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--muted);
  font-size: 0.94rem;
  font-weight: 600;
}

.nav-links a:hover {
  color: var(--ink);
}

.topbar-action,
.primary-button,
.secondary-button,
.add-button {
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  border: 0;
  border-radius: 8px;
  background: var(--teal);
  color: #fff;
  cursor: pointer;
  font-weight: 800;
  padding: 0 18px;
  box-shadow: 0 10px 24px rgba(27, 138, 127, 0.22);
}

.topbar-action:hover,
.primary-button:hover,
.secondary-button:hover,
.add-button:hover {
  background: var(--teal-dark);
}

.app-section {
  padding: 30px 28px 34px;
}

.app-intro {
  display: grid;
  grid-template-columns: minmax(320px, 760px) auto;
  gap: 24px;
  align-items: end;
  width: min(1480px, 100%);
  margin: 0 auto 22px;
}

.app-intro h1 {
  margin: 0;
  max-width: 720px;
  font-size: 2.2rem;
  line-height: 1.08;
  letter-spacing: 0;
  overflow-wrap: anywhere;
}

.app-intro p {
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
}

.hero-line {
  margin-top: 14px !important;
  color: var(--ink) !important;
  font-size: 1.16rem !important;
  font-weight: 900;
}

.app-intro p:not(.eyebrow):not(.hero-line) {
  margin-top: 10px;
  max-width: 680px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}

.eyebrow,
.panel-kicker {
  margin: 0 0 8px;
  color: var(--teal-dark);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.app-shell {
  overflow: hidden;
  width: min(1480px, 100%);
  max-width: 100%;
  min-width: 0;
  margin: 0 auto;
  border: 1px solid #cbd8d5;
  border-radius: 10px;
  background: #ffffff;
  box-shadow: 0 24px 70px rgba(24, 32, 47, 0.14);
}

.mockup-shell {
  display: flex;
  flex-direction: column;
  min-height: 700px;
  border: 0;
  background: transparent;
  box-shadow: none;
}

.mockup-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 72px;
  padding: 0 24px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.94);
}

.mockup-brand img {
  width: 166px;
  height: auto;
}

.mockup-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.sync-status,
.user-menu,
.icon-button,
.inline-icon-button,
.mini-icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
}

.sync-status {
  gap: 8px;
  min-height: 36px;
  border-color: #cfe3df;
  border-radius: 999px;
  color: var(--teal-dark);
  font-size: 0.82rem;
  font-weight: 800;
  padding: 0 13px;
}

.icon-button,
.inline-icon-button,
.mini-icon-button {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  cursor: pointer;
}

.icon-button:hover,
.inline-icon-button:hover,
.mini-icon-button:hover,
.user-menu:hover {
  border-color: #b9d7d3;
  background: #f1faf7;
}

.user-menu {
  gap: 8px;
  min-height: 38px;
  border-radius: 999px;
  cursor: pointer;
  padding: 3px 10px 3px 3px;
}

.avatar {
  display: inline-grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font-size: 0.74rem;
  font-weight: 900;
}

.chevron,
.small-chevron {
  width: 8px;
  height: 8px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
}

.icon,
.nav-icon {
  position: relative;
  display: inline-block;
  width: 18px;
  height: 18px;
  color: currentColor;
}

.cloud-icon::before {
  position: absolute;
  inset: 5px 2px 4px;
  border: 2px solid currentColor;
  border-radius: 10px;
  content: "";
}

.cloud-icon::after {
  position: absolute;
  top: 2px;
  left: 6px;
  width: 8px;
  height: 8px;
  border: 2px solid currentColor;
  border-bottom: 0;
  border-radius: 50% 50% 0 0;
  background: #fff;
  content: "";
}

.moon-icon::before {
  position: absolute;
  inset: 2px;
  border: 2px solid currentColor;
  border-radius: 50%;
  content: "";
}

.moon-icon::after {
  position: absolute;
  top: 1px;
  right: 1px;
  width: 12px;
  height: 14px;
  border-radius: 50%;
  background: #fff;
  content: "";
}

.filter-icon::before,
.filter-icon::after {
  position: absolute;
  left: 3px;
  right: 3px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  content: "";
}

.filter-icon::before {
  top: 5px;
  box-shadow: 0 5px 0 currentColor;
}

.filter-icon::after {
  top: 15px;
  right: 8px;
}

.pencil-icon::before {
  position: absolute;
  top: 3px;
  left: 8px;
  width: 4px;
  height: 14px;
  border-radius: 3px;
  background: currentColor;
  transform: rotate(42deg);
  content: "";
}

.star-icon::before {
  position: absolute;
  inset: 1px;
  background: currentColor;
  clip-path: polygon(50% 0, 61% 35%, 98% 35%, 68% 56%, 80% 96%, 50% 73%, 20% 96%, 32% 56%, 2% 35%, 39% 35%);
  content: "";
}

.tag-line-icon::before {
  position: absolute;
  inset: 3px 2px 3px 4px;
  border: 2px solid currentColor;
  border-radius: 4px;
  transform: skewX(-10deg);
  content: "";
}

.tag-line-icon::after {
  position: absolute;
  top: 6px;
  right: 5px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: currentColor;
  content: "";
}

.dots-icon::before {
  position: absolute;
  top: 8px;
  left: 3px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 6px 0 0 currentColor, 12px 0 0 currentColor;
  content: "";
}

.sparkle-icon::before {
  position: absolute;
  top: 2px;
  left: 5px;
  width: 10px;
  height: 10px;
  background: currentColor;
  clip-path: polygon(50% 0, 62% 38%, 100% 50%, 62% 62%, 50% 100%, 38% 62%, 0 50%, 38% 38%);
  content: "";
}

.sparkle-icon::after {
  position: absolute;
  right: 2px;
  bottom: 2px;
  width: 7px;
  height: 7px;
  background: currentColor;
  clip-path: polygon(50% 0, 62% 38%, 100% 50%, 62% 62%, 50% 100%, 38% 62%, 0 50%, 38% 38%);
  content: "";
}

.image-icon::before {
  position: absolute;
  inset: 3px;
  border: 2px solid currentColor;
  border-radius: 3px;
  content: "";
}

.image-icon::after {
  position: absolute;
  left: 5px;
  bottom: 5px;
  width: 10px;
  height: 7px;
  background: currentColor;
  clip-path: polygon(0 100%, 36% 42%, 58% 70%, 78% 25%, 100% 100%);
  content: "";
}

.checklist-icon::before {
  position: absolute;
  top: 4px;
  left: 3px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 0 6px 0 currentColor, 0 12px 0 currentColor;
  content: "";
}

.checklist-icon::after {
  position: absolute;
  top: 5px;
  left: 10px;
  width: 7px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  box-shadow: 0 6px 0 currentColor, 0 12px 0 currentColor;
  content: "";
}

.mic-icon::before {
  position: absolute;
  top: 2px;
  left: 6px;
  width: 8px;
  height: 11px;
  border: 2px solid currentColor;
  border-radius: 8px;
  content: "";
}

.mic-icon::after {
  position: absolute;
  left: 4px;
  bottom: 1px;
  width: 12px;
  height: 7px;
  border: 2px solid currentColor;
  border-top: 0;
  border-radius: 0 0 10px 10px;
  content: "";
}

.mockup-layout {
  display: grid;
  grid-template-columns: 242px 260px minmax(560px, 1fr);
  gap: 14px;
  flex: 1;
  min-height: 690px;
  padding: 0;
}

.app-sidebar,
.notes-list-panel,
.main-editor-panel {
  min-width: 0;
}

.app-sidebar {
  display: flex;
  flex-direction: column;
  gap: 28px;
  padding: 22px 18px;
  border: 1px solid rgba(214, 224, 222, 0.75);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 18px 42px rgba(24, 32, 47, 0.08);
}

.side-nav {
  display: grid;
  gap: 8px;
}

.side-nav-item,
.subject-item,
.physics-note-card {
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  text-align: left;
}

.side-nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 46px;
  border-radius: 10px;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 800;
  padding: 0 12px;
}

.side-nav-item.is-active,
.side-nav-item:hover {
  background: linear-gradient(90deg, #e4f8f5 0%, #f2fbf9 100%);
  color: var(--teal-dark);
}

.nav-icon::before,
.nav-icon::after {
  position: absolute;
  content: "";
}

.notes-icon::before {
  inset: 2px 4px;
  border: 2px solid currentColor;
  border-radius: 3px;
}

.notes-icon::after {
  top: 7px;
  left: 7px;
  width: 7px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  box-shadow: 0 5px 0 currentColor;
}

.hub-icon::before {
  inset: 3px;
  border: 2px solid currentColor;
  border-radius: 50%;
}

.hub-icon::after {
  top: 8px;
  left: 8px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: -6px -3px 0 currentColor, 6px 3px 0 currentColor;
}

.tag-icon::before {
  inset: 3px 2px 3px 4px;
  border: 2px solid currentColor;
  border-radius: 4px;
  transform: skewX(-10deg);
}

.tag-icon::after {
  top: 7px;
  right: 5px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: currentColor;
}

.calendar-icon::before {
  inset: 3px;
  border: 2px solid currentColor;
  border-radius: 3px;
}

.calendar-icon::after {
  top: 8px;
  left: 5px;
  right: 5px;
  height: 2px;
  background: currentColor;
}

.subjects-block {
  display: grid;
  gap: 12px;
}

.block-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.mini-icon-button {
  width: 26px;
  height: 26px;
  border-radius: 7px;
  color: var(--teal-dark);
  font-size: 1rem;
  font-weight: 900;
}

.subject-list {
  display: grid;
  gap: 6px;
}

.subject-item {
  display: grid;
  grid-template-columns: 16px 1fr auto;
  gap: 10px;
  align-items: center;
  min-height: 42px;
  border-radius: 10px;
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 750;
  padding: 0 10px;
}

.subject-item strong {
  color: #8a94a6;
  font-size: 0.78rem;
}

.subject-item.is-selected,
.subject-item:hover {
  background: linear-gradient(90deg, #e4f8f5 0%, #f6fbfa 100%);
  color: var(--ink);
  box-shadow: none;
}

.subject-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.physics-dot {
  background: var(--teal);
}

.math-dot {
  background: #4f75c6;
}

.chemistry-dot {
  background: #c98a2e;
}

.biology-dot {
  background: #58a76f;
}

.english-dot {
  background: #7560a8;
}

.cs-dot {
  background: #6a7588;
}

.add-subject {
  min-height: 38px;
  border: 0;
  border-radius: 10px;
  background: transparent;
  color: var(--teal-dark);
  cursor: pointer;
  font-weight: 900;
  text-align: left;
  padding: 0 10px;
}

.notes-list-panel {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 22px 14px;
  border: 1px solid rgba(214, 224, 222, 0.75);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 18px 42px rgba(24, 32, 47, 0.08);
}

.notes-list-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.notes-list-head > div {
  display: flex;
  align-items: center;
  gap: 8px;
}

.notes-list-head h2 {
  margin: 0;
  font-size: 1.3rem;
  line-height: 1.1;
}

.filter-button {
  color: var(--muted);
}

.physics-note-list {
  display: grid;
  gap: 8px;
}

.physics-note-card {
  display: grid;
  gap: 5px;
  min-height: 64px;
  align-content: center;
  border: 1px solid transparent;
  border-radius: 10px;
  padding: 12px;
}

.physics-note-card strong {
  font-size: 0.92rem;
  line-height: 1.25;
}

.physics-note-card span {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 750;
}

.physics-note-card.is-selected,
.physics-note-card:hover {
  border-color: transparent;
  background: linear-gradient(105deg, #e4f8f5 0%, #f8fcfb 100%);
  box-shadow: none;
}

.physics-note-card.is-selected {
  position: relative;
}

.physics-note-card.is-selected::after {
  position: absolute;
  right: 12px;
  top: 50%;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
  transform: translateY(-50%);
  content: "";
}

.new-note-button {
  min-height: 44px;
  margin-top: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--teal-dark);
  cursor: pointer;
  font-weight: 900;
  box-shadow: none;
}

.main-editor-panel {
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 26px 34px 24px;
  border: 1px solid rgba(214, 224, 222, 0.75);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 18px 42px rgba(24, 32, 47, 0.08);
}

.editor-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.editor-title-row,
.editor-tools {
  display: flex;
  align-items: center;
  gap: 8px;
}

.editor-title-row h2 {
  margin: 0;
  font-size: 1.35rem;
}

.editor-header p {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 650;
}

.inline-icon-button {
  width: 30px;
  height: 30px;
  border-color: transparent;
  color: var(--muted);
}

.study-note {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 220px;
  column-gap: 24px;
  gap: 18px;
  max-width: none;
  align-items: start;
  color: #14203a;
  font-family: "Patrick Hand", "Comic Sans MS", cursive;
}

.note-heading-row,
.note-content-grid,
.formula-row,
.study-bullets,
.thinking-trace,
.recall-card {
  grid-column: 1;
}

.note-heading-row {
  display: inline-grid;
  justify-items: start;
  gap: 5px;
  width: max-content;
}

.note-heading-row h3 {
  margin: 0;
  font-size: 2rem;
  font-weight: 400;
  line-height: 1.15;
}

.heading-stroke {
  display: block;
  width: 184px;
  height: 5px;
  border-radius: 999px;
  background: var(--teal);
  opacity: 0.8;
}

.note-content-grid {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) 42px;
  gap: 18px;
  align-items: start;
}

.note-copy p {
  margin: 0;
  color: #303b4f;
  font-size: 1.28rem;
  line-height: 1.32;
}

.ink-underline {
  background: transparent;
  color: inherit;
  text-decoration: underline;
  text-decoration-color: var(--teal);
  text-decoration-thickness: 3px;
  text-underline-offset: 5px;
}

.learning-marker {
  display: inline-grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 8px;
  font-family: Inter, system-ui, sans-serif;
  font-size: 1rem;
  font-weight: 900;
}

.question-marker {
  background: #dff6f2;
  color: var(--teal-dark);
}

.important-marker {
  background: var(--teal);
  color: #fff;
}

.formula-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.formula-card {
  min-width: 260px;
  border: 0;
  border-radius: 8px;
  background: #eef9f7;
  color: var(--teal-dark);
  font-size: 1.75rem;
  font-weight: 400;
  text-align: center;
  padding: 13px 20px;
}

.frac {
  display: inline-grid;
  grid-template-rows: 1fr 1fr;
  align-items: center;
  justify-items: center;
  margin: 0 4px;
  vertical-align: middle;
  line-height: 0.85;
}

.frac span:first-child {
  border-bottom: 2px solid currentColor;
  padding: 0 4px 3px;
}

.frac span:last-child {
  padding-top: 3px;
}

.important-callout {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--teal-dark);
  font-size: 1.22rem;
}

.important-callout strong {
  border-bottom: 3px solid var(--teal);
  font-weight: 400;
}

.study-bullets {
  margin: 0;
  padding-left: 22px;
  color: #303b4f;
  font-size: 1.22rem;
  font-weight: 400;
}

.thinking-trace {
  display: grid;
  gap: 10px;
  padding: 0 0 0 8px;
  border: 0;
  background: transparent;
}

.wrong-line {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.wrong-line del {
  color: #18202f;
  font-size: 1.32rem;
  font-weight: 400;
}

.mistake-cross {
  color: #ff4949;
  font-family: Inter, system-ui, sans-serif;
  font-size: 1.15rem;
  font-weight: 900;
}

.incorrect-label {
  color: #ff4949;
  font-size: 1.1rem;
  font-weight: 400;
}

.error-dot {
  display: inline-grid;
  width: 26px;
  height: 26px;
  place-items: center;
  border-radius: 50%;
  background: #f7d7d4;
  color: var(--rose);
  font-weight: 950;
}

.corrected-line {
  color: #168a34;
  font-size: 1.56rem;
  font-weight: 400;
}

.side-learning-markers {
  grid-column: 2;
  grid-row: 5 / span 2;
  display: grid;
  gap: 10px;
  width: 100%;
  margin-top: 10px;
}

.side-marker-item {
  display: flex;
  gap: 8px;
  align-items: center;
  min-height: 34px;
  border: 0;
  background: transparent;
  color: #303b4f;
  font-size: 1.12rem;
  font-weight: 400;
  padding: 0;
  box-shadow: none;
}

.label-chip {
  display: inline-grid;
  min-width: 42px;
  min-height: 28px;
  place-items: center;
  border-radius: 7px;
  background: #fff !important;
  font-family: Inter, system-ui, sans-serif;
  font-size: 0.82rem;
  font-weight: 900;
}

.homework-chip {
  border: 2px solid #ff990f;
  color: #ff990f;
}

.test-chip {
  border: 2px solid #9058ff;
  color: #9058ff;
}

.recall-card {
  display: grid;
  gap: 7px;
  max-width: 360px;
  border: 0;
  background: transparent;
  color: #1f5cc5;
  padding: 18px 0 0 44px;
}

.recall-card span {
  color: #174eb5;
  font-size: 1.2rem;
  font-weight: 400;
}

.recall-card strong {
  position: relative;
  font-size: 1.22rem;
  font-weight: 400;
}

.recall-card strong::before {
  position: absolute;
  left: -40px;
  top: 0;
  color: #1f6eea;
  font-family: Inter, system-ui, sans-serif;
  font-size: 1.6rem;
  content: "↻";
}

.thought-input {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 14px;
  align-items: center;
  min-height: 58px;
  margin-top: auto;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fbfcfb;
  color: var(--muted);
  font-size: 0.96rem;
  font-weight: 650;
  padding: 8px 10px 8px 18px;
}

.thought-tools {
  display: flex;
  gap: 6px;
}

.app-chrome {
  display: grid;
  grid-template-columns: 96px 1fr auto;
  gap: 16px;
  align-items: center;
  min-height: 50px;
  padding: 0 18px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, #ffffff 0%, #f5f8f7 100%);
}

.chrome-dots {
  display: flex;
  gap: 8px;
}

.chrome-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #ced8d5;
}

.chrome-dots span:nth-child(1) {
  background: #e58c81;
}

.chrome-dots span:nth-child(2) {
  background: #e8bf6a;
}

.chrome-dots span:nth-child(3) {
  background: #65bf9c;
}

.chrome-title {
  color: var(--ink);
  font-size: 0.9rem;
  font-weight: 900;
  text-align: center;
}

.chrome-status {
  display: inline-flex;
  min-height: 30px;
  align-items: center;
  border: 1px solid #cfe3df;
  border-radius: 999px;
  background: #eef8f5;
  color: var(--teal-dark);
  font-size: 0.76rem;
  font-weight: 900;
  padding: 0 10px;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(230px, 280px) minmax(420px, 1fr) minmax(280px, 340px);
  gap: 14px;
  width: 100%;
  min-width: 0;
  min-height: 660px;
  margin: 0;
  padding: 14px;
  background: #eef4f2;
}

.session-panel,
.note-panel,
.signals-panel {
  min-width: 0;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: none;
}

.session-panel,
.signals-panel {
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 18px;
  border-radius: 8px;
}

.session-panel {
  background: #f9fbfa;
}

.note-panel {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-color: #cbd8d5;
  border-radius: 8px;
  background: #ffffff;
  box-shadow: 0 14px 40px rgba(24, 32, 47, 0.1);
}

.signals-panel {
  background: #f7fbfa;
}

.panel-heading,
.signals-header,
.note-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}

.panel-heading strong,
.signals-header strong {
  font-size: 1.1rem;
}

.session-panel .panel-heading,
.signals-panel .signals-header {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.session-form,
.reflection-form {
  display: grid;
  gap: 12px;
}

label {
  display: grid;
  gap: 6px;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
}

input,
textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfb;
  color: var(--ink);
  outline: none;
}

input {
  min-height: 40px;
  padding: 0 11px;
}

textarea {
  resize: vertical;
  padding: 10px 11px;
}

input:focus,
textarea:focus {
  border-color: rgba(27, 138, 127, 0.6);
  box-shadow: 0 0 0 3px rgba(27, 138, 127, 0.12);
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.note-list {
  display: grid;
  gap: 8px;
}

.note-tab {
  display: grid;
  gap: 3px;
  width: 100%;
  min-height: 62px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  text-align: left;
}

.note-tab span {
  color: var(--muted);
  font-size: 0.74rem;
  font-weight: 700;
}

.note-tab strong {
  font-size: 0.9rem;
}

.note-tab.is-active {
  border-color: rgba(27, 138, 127, 0.45);
  background: var(--surface-soft);
}

.note-head {
  padding: 20px 20px 16px;
  border-bottom: 1px solid var(--line);
}

.note-head h2 {
  margin: 0;
  font-size: 1.3rem;
  line-height: 1.2;
}

.note-status {
  flex: 0 0 auto;
  min-height: 32px;
  padding: 6px 10px;
  border-radius: 999px;
  background: #eef4f2;
  color: var(--teal-dark);
  font-size: 0.78rem;
  font-weight: 800;
}

.toolbar {
  display: grid;
  grid-template-columns: repeat(8, minmax(50px, 1fr));
  gap: 8px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--line);
  background: #eef4f2;
}

.tool-button {
  display: inline-grid;
  height: 42px;
  min-width: 42px;
  place-items: center;
  border: 1px solid #cfd9d6;
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  font-size: 1rem;
  font-weight: 900;
  box-shadow: 0 6px 14px rgba(24, 32, 47, 0.06);
}

.tool-button.text-tool {
  font-size: 0.78rem;
}

.tool-button:hover,
.tool-button.is-selected {
  border-color: rgba(27, 138, 127, 0.5);
  background: #e6f5f1;
  color: var(--teal-dark);
}

.tool-button[data-marker="question"] {
  background: #f3effb;
  color: var(--purple);
}

.tool-button[data-marker="important"] {
  background: #edf2ff;
  color: var(--blue);
}

.tool-button[data-marker="homework"] {
  background: #fff4df;
  color: var(--amber);
}

.tool-button[data-marker="test"] {
  background: #fff0ef;
  color: var(--rose);
}

.tool-button[data-marker="mistake"],
.tool-button[data-marker="change"] {
  background: #f8f1e8;
  color: #8b6f47;
}

.tool-button[data-marker="understood"] {
  background: #e6f5f1;
  color: var(--teal-dark);
}

.tool-button.is-selected {
  outline: 3px solid rgba(27, 138, 127, 0.16);
}

.compose-row {
  display: grid;
  grid-template-columns: 1fr 82px;
  gap: 10px;
  padding: 16px 20px 10px;
}

.compose-row textarea {
  min-height: 88px;
}

.add-button {
  align-self: stretch;
  min-height: 88px;
}

.trace-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 0 20px 14px;
}

.trace-actions button {
  min-height: 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  font-size: 0.84rem;
  font-weight: 800;
  padding: 0 12px;
}

.trace-actions button:hover {
  border-color: rgba(79, 117, 198, 0.5);
  background: #edf2ff;
  color: #2f559f;
}

.note-stream {
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 10px;
  overflow: auto;
  min-height: 280px;
  padding: 4px 20px 20px;
}

.note-entry {
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 12px;
  padding: 12px;
  border: 1px solid var(--line);
  border-left-width: 4px;
  border-radius: 8px;
  background: #fff;
  cursor: pointer;
}

.note-entry.is-active {
  border-color: rgba(79, 117, 198, 0.52);
  box-shadow: 0 0 0 3px rgba(79, 117, 198, 0.1);
}

.note-entry.is-crossed .entry-text {
  color: #7d8795;
  text-decoration: line-through;
}

.note-entry.is-faded {
  opacity: 0.56;
}

.note-entry.question {
  border-left-color: var(--purple);
}

.note-entry.important {
  border-left-color: var(--blue);
}

.note-entry.homework {
  border-left-color: var(--amber);
}

.note-entry.test {
  border-left-color: var(--rose);
}

.note-entry.mistake,
.note-entry.change {
  border-left-color: #8b6f47;
}

.note-entry.understood {
  border-left-color: var(--teal);
}

.entry-time {
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 800;
}

.entry-text {
  margin: 0;
  white-space: pre-wrap;
}

.marker-pill {
  display: inline-flex;
  min-width: 34px;
  min-height: 26px;
  align-items: center;
  justify-content: center;
  margin-right: 8px;
  border-radius: 999px;
  background: #eef4f2;
  color: var(--teal-dark);
  font-size: 0.75rem;
  font-weight: 900;
  vertical-align: middle;
}

.signal-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.signal-metrics div {
  display: grid;
  gap: 2px;
  min-height: 70px;
  align-content: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfb;
  text-align: center;
}

.signal-metrics span {
  color: var(--ink);
  font-size: 1.35rem;
  font-weight: 900;
}

.signal-metrics small {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 800;
}

.timeline {
  display: flex;
  flex-direction: column;
  gap: 9px;
  overflow: auto;
  max-height: 250px;
  padding-right: 4px;
}

.timeline-item {
  position: relative;
  padding: 0 0 0 18px;
}

.timeline-item::before {
  position: absolute;
  top: 8px;
  left: 0;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--teal);
  content: "";
}

.timeline-item strong {
  display: block;
  font-size: 0.78rem;
}

.timeline-item span {
  display: block;
  color: var(--muted);
  font-size: 0.76rem;
}

.trust-micro {
  margin: -2px 0 0;
  padding: 10px 12px;
  border: 1px solid #cfe3df;
  border-radius: 8px;
  background: #ffffff;
  color: var(--teal-dark);
  font-size: 0.78rem;
  font-weight: 900;
}

.secondary-button {
  width: 100%;
  background: var(--ink);
  box-shadow: none;
}

.secondary-button:hover {
  background: #2a3446;
}

.content-band {
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(320px, 1.1fr);
  gap: 48px;
  align-items: center;
  width: min(1180px, calc(100% - 56px));
  margin: 0 auto;
  padding: 78px 0;
}

.section-copy h2,
.closing-section h2 {
  margin: 0;
  font-size: 2rem;
  line-height: 1.15;
  letter-spacing: 0;
}

.section-copy p:not(.eyebrow) {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 1.04rem;
}

.trust-note {
  border-left: 4px solid var(--teal);
  border-radius: 0 8px 8px 0;
  background: #eef8f5;
  color: var(--ink) !important;
  font-size: 0.98rem !important;
  font-weight: 700;
  padding: 14px 16px;
}

.comparison-table {
  display: grid;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}

.comparison-table > div {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.comparison-table > div + div {
  border-top: 1px solid var(--line);
}

.comparison-table strong,
.comparison-table span {
  padding: 16px;
}

.comparison-table strong {
  background: #eef4f2;
  color: var(--teal-dark);
}

.comparison-table span + span,
.comparison-table strong + strong {
  border-left: 1px solid var(--line);
}

.trace-section {
  grid-template-columns: minmax(320px, 1.1fr) minmax(280px, 0.9fr);
}

.product-visual {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--shadow);
}

.product-visual img {
  width: 100%;
  height: auto;
}

.formula-trace {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.formula-trace span,
.formula-trace del,
.formula-trace strong {
  min-height: 42px;
  padding: 9px 13px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  font-size: 1rem;
}

.formula-trace del {
  color: var(--muted);
}

.formula-trace strong {
  border-color: rgba(27, 138, 127, 0.35);
  color: var(--teal-dark);
}

.features-section {
  width: min(1180px, calc(100% - 56px));
  margin: 0 auto;
  padding: 82px 0;
}

.centered {
  max-width: 680px;
  margin: 0 auto 28px;
  text-align: center;
}

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

.feature-grid article {
  min-height: 190px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.feature-icon {
  display: inline-grid;
  width: 40px;
  height: 32px;
  place-items: center;
  border-radius: 8px;
  background: #edf2ff;
  color: #315aa6;
  font-size: 0.74rem;
  font-weight: 900;
}

.feature-grid h3 {
  margin: 16px 0 8px;
  font-size: 1.02rem;
}

.feature-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.signal-map {
  display: grid;
  gap: 12px;
}

.signal-map div {
  min-height: 56px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  font-weight: 900;
  box-shadow: 0 10px 24px rgba(25, 35, 48, 0.08);
}

.signal-map span {
  width: 2px;
  height: 24px;
  margin: 0 auto;
  background: var(--teal);
}

.closing-section {
  width: min(900px, calc(100% - 56px));
  margin: 0 auto;
  padding: 82px 0 100px;
  text-align: center;
}

.closing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  margin-top: 24px;
}

.secondary-link {
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  font-weight: 800;
  padding: 0 18px;
}

.secondary-link:hover {
  border-color: rgba(27, 138, 127, 0.45);
  color: var(--teal-dark);
}

@media (max-width: 1160px) {
  .mockup-layout {
    grid-template-columns: 210px minmax(240px, 290px) minmax(420px, 1fr);
  }

  .side-learning-markers {
    position: static;
    grid-column: 1;
    grid-row: auto;
    width: 100%;
  }

  .study-note {
    grid-template-columns: 1fr;
  }

  .workspace {
    grid-template-columns: 240px minmax(360px, 1fr);
  }

  .signals-panel {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: 1fr 1fr 1.2fr;
    align-items: start;
  }

  .timeline {
    max-height: 220px;
  }
}

@media (max-width: 860px) {
  .topbar {
    padding: 10px 16px;
  }

  .nav-links {
    display: none;
  }

  .app-section {
    padding: 24px 16px 24px;
  }

  .mockup-topbar {
    flex-wrap: wrap;
    min-height: auto;
    padding: 14px;
  }

  .mockup-actions {
    width: 100%;
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .mockup-layout {
    grid-template-columns: 1fr;
  }

  .app-sidebar,
  .notes-list-panel {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .side-nav,
  .subject-list,
  .physics-note-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .new-note-button {
    margin-top: 0;
  }

  .app-intro {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    justify-content: flex-start;
  }

  .app-chrome {
    grid-template-columns: auto 1fr;
  }

  .chrome-title {
    text-align: left;
  }

  .chrome-status {
    display: none;
  }

  .app-intro h1 {
    font-size: 1.7rem;
  }

  .workspace,
  .content-band,
  .trace-section {
    grid-template-columns: 1fr;
  }

  .workspace {
    min-height: auto;
  }

  .session-panel,
  .signals-panel {
    box-shadow: none;
  }

  .signals-panel {
    display: flex;
  }

  .content-band,
  .features-section,
  .closing-section {
    width: calc(100% - 32px);
    padding: 58px 0;
  }

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

@media (max-width: 560px) {
  .topbar-action {
    display: none;
  }

  .brand-logo {
    width: 148px;
  }

  .app-intro h1 {
    font-size: 1.45rem;
    line-height: 1.14;
  }

  .app-intro,
  .app-intro > div {
    max-width: calc(100vw - 32px);
  }

  .hero-line {
    font-size: 1rem !important;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .hero-actions .primary-button,
  .hero-actions .secondary-link {
    width: 100%;
  }

  .app-shell {
    width: calc(100vw - 32px);
  }

  .mockup-brand img {
    width: 142px;
  }

  .sync-status {
    font-size: 0.76rem;
    padding: 0 10px;
  }

  .mockup-actions {
    gap: 8px;
  }

  .app-sidebar,
  .notes-list-panel,
  .main-editor-panel {
    padding: 16px 14px;
  }

  .side-nav,
  .subject-list,
  .physics-note-list {
    grid-template-columns: 1fr;
  }

  .editor-header,
  .thought-input,
  .note-content-grid {
    grid-template-columns: 1fr;
  }

  .editor-header {
    display: grid;
  }

  .editor-tools {
    justify-content: flex-start;
  }

  .note-heading-row h3 {
    font-size: 1.3rem;
  }

  .formula-card {
    min-width: 0;
    width: 100%;
  }

  .thought-tools {
    flex-wrap: wrap;
  }

  .session-panel,
  .note-panel,
  .signals-panel {
    max-width: calc(100vw - 52px);
  }

  .app-chrome {
    gap: 10px;
    padding: 0 12px;
  }

  .chrome-title {
    font-size: 0.78rem;
  }

  .workspace {
    gap: 10px;
    padding: 10px;
  }

  .session-panel,
  .signals-panel {
    padding: 14px;
  }

  .panel-heading,
  .signals-header,
  .note-head {
    flex-wrap: wrap;
  }

  .toolbar {
    grid-template-columns: repeat(4, 1fr);
    padding: 12px;
  }

  .note-head,
  .compose-row,
  .trace-actions,
  .note-stream {
    padding-left: 12px;
    padding-right: 12px;
  }

  .compose-row {
    grid-template-columns: 1fr;
  }

  .add-button {
    min-height: 42px;
  }

  .form-grid,
  .signal-metrics,
  .comparison-table > div,
  .feature-grid {
    grid-template-columns: 1fr;
  }

  .comparison-table span + span,
  .comparison-table strong + strong {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .note-entry {
    grid-template-columns: 1fr;
  }

  .section-copy h2,
  .closing-section h2 {
    font-size: 1.55rem;
  }
}