/* =====================================================
   Investment Return Calculator — investment-return.css
   Chedders Tools
   ===================================================== */

:root {
  --primary: #0b1f3a;
  --primary-light: #16345f;
  --background: #ffffff;
  --surface: #f8f9fa;
  --text: #111111;
  --muted: #6c757d;
  --border: #e5e7eb;
  --shadow: rgba(0,0,0,0.05);
  --up: #198754;
  --down: #dc3545;
}

[data-theme="dark"] {
  --background: #081120;
  --surface: #0f1c2e;
  --text: #ffffff;
  --muted: #b0b7c3;
  --border: rgba(255,255,255,0.08);
  --shadow: rgba(0,0,0,0.3);
}

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

body {
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
  background: var(--background);
  margin: 0;
  transition: background-color 0.25s ease, color 0.25s ease;
}

.container-xl { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* --- Navbar --- */
.navbar {
  height: 60px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  transition: background-color 0.25s ease, border-color 0.25s ease;
}
.navbar .container-xl { display: flex; align-items: center; justify-content: space-between; width: 100%; }
.navbar-brand { text-decoration: none; display: flex; align-items: center; }
.brand-text { font-weight: 700; color: var(--primary); font-size: 16px; }
.brand-dot  { color: var(--primary); font-weight: 700; font-size: 16px; }
.brand-tools{ font-weight: 400; color: var(--muted); font-size: 16px; }
[data-theme="dark"] .brand-text, [data-theme="dark"] .brand-dot { color: #ffffff; }
.nav-right { display: flex; align-items: center; gap: 16px; }
.nav-back { font-size: 14px; color: var(--muted); text-decoration: none; transition: color 0.2s; }
.nav-back:hover { color: var(--primary); }
[data-theme="dark"] .nav-back:hover { color: #ffffff; }
.theme-toggle { background: none; border: 1px solid var(--border); border-radius: 6px; padding: 6px 10px; cursor: pointer; transition: background-color 0.2s; }
.theme-toggle:hover { background: var(--background); }
.theme-icon { font-size: 14px; line-height: 1; display: block; }

/* --- Header --- */
.tool-header { padding: 40px 0 24px; border-bottom: 1px solid var(--border); }
.tool-title { font-size: 28px; font-weight: 700; color: var(--primary); margin: 0; transition: color 0.25s ease; }
[data-theme="dark"] .tool-title { color: #ffffff; }
.tool-description { font-size: 15px; color: var(--muted); margin: 6px 0 0; }

.tool-main { padding: 32px 0 80px; }

/* --- Layout --- */
.calc-layout {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 24px;
  align-items: start;
}

/* --- Card --- */
.tool-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 24px;
  box-shadow: 0 2px 8px var(--shadow);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.section-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--primary);
  margin: 0 0 20px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
}
[data-theme="dark"] .section-title { color: #ffffff; }

/* --- Fields --- */
.field-group { display: flex; flex-direction: column; gap: 6px; margin-bottom: 18px; }
.field-label { font-size: 14px; font-weight: 600; color: var(--text); }

.form-input {
  background: var(--background);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px 14px;
  color: var(--text);
  font-family: inherit;
  font-size: 15px;
  height: 44px;
  width: 100%;
  outline: none;
  transition: border-color 0.2s, background-color 0.25s ease;
}
.form-input:focus { border-color: var(--primary); outline: 2px solid var(--primary); outline-offset: 2px; }
.form-input.is-error { border-color: var(--down); }

/* --- Prefix input --- */
.input-prefix-wrap {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  transition: border-color 0.2s;
}
.input-prefix-wrap:focus-within { border-color: var(--primary); outline: 2px solid var(--primary); outline-offset: 2px; }

.input-prefix {
  background: var(--surface);
  border-right: 1px solid var(--border);
  padding: 0 12px;
  display: flex;
  align-items: center;
  font-size: 15px;
  font-weight: 600;
  color: var(--muted);
  user-select: none;
  white-space: nowrap;
}

.prefix-input {
  border: none;
  border-radius: 0;
  flex: 1;
  outline: none;
}
.prefix-input:focus { outline: none; }

/* --- Period row --- */
.period-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.period-input { flex: 1; }
.period-sep { font-size: 14px; color: var(--muted); white-space: nowrap; }

.select-input { cursor: pointer; }

/* --- Error --- */
.field-error { font-size: 13px; color: var(--down); margin: 0; min-height: 18px; }

/* --- Buttons --- */
.btn-row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 8px; }

.btn-primary-tool {
  background: var(--primary);
  color: #ffffff;
  border: none;
  border-radius: 6px;
  padding: 10px 24px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  min-height: 44px;
  transition: background-color 0.2s;
}
.btn-primary-tool:hover { background: var(--primary-light); }

.btn-secondary-tool {
  background: var(--background);
  color: var(--primary);
  border: 1px solid var(--primary);
  border-radius: 6px;
  padding: 10px 24px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  min-height: 44px;
  transition: background-color 0.2s, color 0.2s;
}
.btn-secondary-tool:hover { background: var(--primary); color: #ffffff; }
[data-theme="dark"] .btn-secondary-tool { border-color: var(--border); color: var(--text); }
[data-theme="dark"] .btn-secondary-tool:hover { background: var(--primary-light); color: #ffffff; border-color: var(--primary-light); }

/* --- Results panel --- */
.results-panel {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.result-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  box-shadow: 0 2px 8px var(--shadow);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.result-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 6px;
}

.result-value {
  font-size: 26px;
  font-weight: 700;
  color: var(--text);
  font-family: 'Courier New', monospace;
  line-height: 1.2;
}

.result-value.positive { color: var(--up); }
.result-value.negative { color: var(--down); }

/* --- Breakdown --- */
.breakdown-card {
  grid-column: 1 / -1;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 2px 8px var(--shadow);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.breakdown-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.breakdown-table th {
  background: var(--primary);
  color: #ffffff;
  padding: 10px 16px;
  text-align: left;
  font-weight: 600;
  font-size: 13px;
}

.breakdown-table td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
}

.breakdown-table tr:last-child td { border-bottom: none; }
.breakdown-table tr:nth-child(even) td { background: var(--background); }

.td-value {
  font-family: 'Courier New', monospace;
  font-weight: 600;
  text-align: right;
}

/* --- Disclaimer --- */
.disclaimer {
  grid-column: 1 / -1;
  font-size: 12px;
  color: var(--muted);
  font-style: italic;
  margin: 4px 0 0;
}

/* --- Footer --- */
.site-footer { padding: 24px 0; border-top: 1px solid var(--border); }
.footer-text { font-size: 13px; color: var(--muted); text-align: center; margin: 0; }
.footer-text a { color: var(--primary); text-decoration: none; }
[data-theme="dark"] .footer-text a { color: #ffffff; }
.footer-text a:hover { text-decoration: underline; }

/* --- Responsive --- */
@media (max-width: 991px) {
  .calc-layout { grid-template-columns: 1fr; }
  .results-panel { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 575px) {
  .tool-title { font-size: 22px; }
  .results-panel { grid-template-columns: 1fr; }
  .result-value { font-size: 22px; }
  .btn-primary-tool, .btn-secondary-tool { width: 100%; }
}