*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:       #0d110d;
  --surface:  #111811;
  --card:     #162016;
  --card2:    #1a261a;
  --border:   #2a6b2a;
  --border-lo:#1a3a1a;
  --green:    #3dba3d;
  --green-dk: #1e7a1e;
  --green-btn:#268c26;
  --text:     #eaf4ea;
  --muted:    #7aaa7a;
  --dimmed:   #4a7a4a;
  --danger:   #7a2020;
  --danger-hi:#c43c3c;
  --row-hover:#1e2e1e;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  min-height: 100vh;
  padding: 0 0 4rem;
}

/* ── Top bar ── */
.topbar {
  background: var(--surface);
  border-bottom: 1px solid var(--border-lo);
  padding: 1.1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.topbar h1 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--green);
  letter-spacing: 0.02em;
}
.topbar .toggle-wrap {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.82rem;
  color: var(--muted);
}
.toggle-wrap label { cursor: pointer; user-select: none; }
.toggle {
  position: relative;
  display: inline-block;
  width: 42px;
  height: 22px;
}
.toggle input { opacity: 0; width: 0; height: 0; }
.slider {
  position: absolute;
  inset: 0;
  background: var(--border-lo);
  border-radius: 22px;
  cursor: pointer;
  transition: background 0.2s;
}
.slider::before {
  content: '';
  position: absolute;
  width: 16px; height: 16px;
  left: 3px; bottom: 3px;
  background: #fff;
  border-radius: 50%;
  transition: transform 0.2s;
}
.toggle input:checked + .slider { background: var(--green-dk); }
.toggle input:checked + .slider::before { transform: translateX(20px); }

/* ── Page body ── */
.page { max-width: 820px; margin: 0 auto; padding: 1.5rem 1rem; }

/* ── Info banner ── */
.banner {
  background: var(--surface);
  border: 1px solid var(--border-lo);
  border-left: 3px solid var(--green);
  border-radius: 8px;
  padding: 0.9rem 1.1rem;
  margin-bottom: 1.5rem;
  font-size: 0.83rem;
  color: var(--muted);
  line-height: 1.6;
}
.banner strong { color: var(--text); }

/* ── GPA summary ── */
.summary {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.75rem;
}
.gpa-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem 1rem;
  text-align: center;
}
.gpa-box .lbl {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--muted);
  margin-bottom: 0.45rem;
}
.gpa-box .num {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--green);
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.gpa-box .sub {
  font-size: 0.7rem;
  color: var(--dimmed);
  margin-top: 0.3rem;
}

/* ── Semester card ── */
.semester-card {
  background: var(--surface);
  border: 1px solid var(--border-lo);
  border-radius: 10px;
  margin-bottom: 1rem;
  overflow: hidden;
}
.semester-header {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.75rem 1rem;
  background: var(--card);
  border-bottom: 1px solid var(--border-lo);
}
.sem-name-input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 600;
  outline: none;
  min-width: 0;
}
.sem-name-input::placeholder { color: var(--dimmed); }
.sem-gpa-badge {
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
  padding: 0.2rem 0.6rem;
  background: var(--border-lo);
  border-radius: 20px;
}
.sem-gpa-badge span { color: var(--green); font-weight: 700; }

/* ── Course rows ── */
.course-table { width: 100%; }
.col-headers {
  display: grid;
  grid-template-columns: 2.5fr 1fr 1.4fr 0.8fr 2rem;
  gap: 0.5rem;
  padding: 0.4rem 1rem;
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--dimmed);
  border-bottom: 1px solid var(--border-lo);
}
.course-row {
  display: grid;
  grid-template-columns: 2.5fr 1fr 1.4fr 0.8fr 2rem;
  gap: 0.5rem;
  align-items: center;
  padding: 0.45rem 1rem;
  border-bottom: 1px solid var(--border-lo);
  transition: background 0.12s;
}
.course-row:hover { background: var(--row-hover); }
.course-row:last-of-type { border-bottom: none; }

.cell-input {
  background: transparent;
  border: 1px solid transparent;
  border-radius: 5px;
  color: var(--text);
  font-size: 0.875rem;
  padding: 0.3rem 0.4rem;
  width: 100%;
  outline: none;
  transition: border-color 0.15s, background 0.15s;
}
.cell-input:hover  { border-color: var(--border-lo); background: var(--card2); }
.cell-input:focus  { border-color: var(--border);    background: var(--card2); }
.cell-input::placeholder { color: var(--dimmed); }
select.cell-input option { background: #1a261a; }

.del-row {
  background: none;
  border: none;
  color: var(--dimmed);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 0.2rem 0.3rem;
  border-radius: 4px;
  transition: color 0.15s, background 0.15s;
  text-align: center;
}
.del-row:hover { color: var(--danger-hi); background: #2a1010; }

/* ── Semester footer ── */
.sem-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 1rem;
  border-top: 1px solid var(--border-lo);
  background: var(--card);
}
.btn-add-course {
  background: none;
  border: 1px dashed var(--border);
  border-radius: 6px;
  color: var(--green);
  cursor: pointer;
  font-size: 0.82rem;
  padding: 0.35rem 0.8rem;
  transition: background 0.15s, border-color 0.15s;
}
.btn-add-course:hover { background: var(--card2); border-color: var(--green); }

.btn-del-sem {
  background: none;
  border: none;
  color: var(--dimmed);
  cursor: pointer;
  font-size: 0.75rem;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: color 0.15s, background 0.15s;
}
.btn-del-sem:hover { color: var(--danger-hi); background: #2a1010; }

/* ── Add semester ── */
.btn-add-sem {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  width: 100%;
  background: none;
  border: 1px dashed var(--border);
  border-radius: 10px;
  color: var(--green);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 0.85rem;
  margin-bottom: 1rem;
  transition: background 0.15s, border-color 0.15s;
}
.btn-add-sem:hover { background: var(--card); border-color: var(--green); }

/* ── Scale reference ── */
.scale-section {
  margin-top: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border-lo);
  border-radius: 10px;
  padding: 1rem 1.1rem;
}
.scale-section h3 {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.75rem;
}
.scale-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}
.scale-chip {
  background: var(--card);
  border: 1px solid var(--border-lo);
  border-radius: 6px;
  padding: 0.35rem 0.7rem;
  font-size: 0.78rem;
  text-align: center;
}
.scale-chip .r { color: var(--text); font-weight: 600; }
.scale-chip .p { color: var(--dimmed); font-size: 0.7rem; margin-top: 0.1rem; }
.weight-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}
.weight-chip {
  background: var(--card);
  border: 1px solid var(--border-lo);
  border-radius: 6px;
  padding: 0.3rem 0.65rem;
  font-size: 0.76rem;
  color: var(--muted);
}
.weight-chip strong { color: var(--text); }

@media (max-width: 580px) {
  .summary { grid-template-columns: 1fr; }
  .col-headers, .course-row {
    grid-template-columns: 1.8fr 0.9fr 1.2fr 0.7fr 1.8rem;
    font-size: 0.78rem;
  }
}