/* ===== DESIGN TOKENS (matching donnyong.com) ===== */
:root {
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);
  --text-3xl:  clamp(2.5rem,   1rem    + 4vw,    5rem);

  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  --font-display: 'Nunito Sans', 'Helvetica Neue', Arial, sans-serif;
  --font-body: 'Nunito Sans', 'Helvetica Neue', Arial, sans-serif;

  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-full: 9999px;

  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
}

/* ===== LIGHT MODE ===== */
:root, [data-theme="light"] {
  --color-bg:             #FAF9F6;
  --color-surface:        #FFFFFF;
  --color-surface-2:      #F5F3EF;
  --color-surface-offset: #EEEAE4;
  --color-border:         #D6D0C7;
  --color-divider:        #E2DDD6;

  --color-text:           #1A1A18;
  --color-text-muted:     #6B6860;
  --color-text-faint:     #A8A49C;
  --color-text-inverse:   #FAF9F6;

  --color-primary:        #1B4332;
  --color-primary-hover:  #143526;
  --color-primary-light:  #D4E4DB;

  --color-accent:         #8B6F47;
  --color-accent-hover:   #735B39;
  --color-accent-light:   #F0E8DB;

  --shadow-sm: 0 1px 2px rgba(40, 35, 25, 0.06);
  --shadow-md: 0 4px 12px rgba(40, 35, 25, 0.08);
  --shadow-lg: 0 12px 32px rgba(40, 35, 25, 0.12);
}

/* ===== DARK MODE ===== */
[data-theme="dark"] {
  --color-bg:             #111110;
  --color-surface:        #1A1918;
  --color-surface-2:      #222120;
  --color-surface-offset: #1E1D1C;
  --color-border:         #3A3835;
  --color-divider:        #2A2928;

  --color-text:           #E2E0DC;
  --color-text-muted:     #9B9890;
  --color-text-faint:     #5C5A56;
  --color-text-inverse:   #111110;

  --color-primary:        #7CB896;
  --color-primary-hover:  #5FA37D;
  --color-primary-light:  #1E2F25;

  --color-accent:         #C9A872;
  --color-accent-hover:   #B08F56;
  --color-accent-light:   #2A2318;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.4);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #111110;
    --color-surface: #1A1918;
    --color-surface-2: #222120;
    --color-surface-offset: #1E1D1C;
    --color-border: #3A3835;
    --color-divider: #2A2928;
    --color-text: #E2E0DC;
    --color-text-muted: #9B9890;
    --color-text-faint: #5C5A56;
    --color-text-inverse: #111110;
    --color-primary: #7CB896;
    --color-primary-hover: #5FA37D;
    --color-primary-light: #1E2F25;
    --color-accent: #C9A872;
    --color-accent-hover: #B08F56;
    --color-accent-light: #2A2318;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.4);
  }
}

/* ===== LAYOUT ===== */
.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-4);
}

.container--narrow {
  max-width: var(--content-default);
}

/* ===== HEADER ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: #FFFFFF;
  border-bottom: 1px solid #E8E8E8;
  transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out);
}

[data-theme="dark"] .header {
  background: #1A1918;
  border-bottom-color: #333;
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.5rem;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-4);
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.header__logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.header__logo-name {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0;
  color: #181818;
}

[data-theme="dark"] .header__logo-name {
  color: var(--color-text);
}

.header__logo-sub {
  font-family: var(--font-display);
  font-size: 0.7rem;
  font-weight: 300;
  color: #181818;
  letter-spacing: 0;
}

[data-theme="dark"] .header__logo-sub {
  color: var(--color-text);
}

.header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.header__nav a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  transition: color var(--transition-interactive), background var(--transition-interactive);
}

.header__nav a:hover {
  color: var(--color-text);
  background: rgba(26, 26, 24, 0.05);
}

.header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  color: var(--color-text-muted);
  transition: color var(--transition-interactive), background var(--transition-interactive);
}

.theme-toggle:hover {
  color: var(--color-text);
  background: rgba(26, 26, 24, 0.06);
}

.mobile-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  color: var(--color-text);
}

.mobile-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  position: relative;
  transition: background 0.2s;
}

.mobile-toggle span::before,
.mobile-toggle span::after {
  content: '';
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition: transform 0.3s var(--ease-out);
}

.mobile-toggle span::before { top: -6px; }
.mobile-toggle span::after { top: 6px; }

.mobile-nav {
  display: none;
  flex-direction: column;
  padding: var(--space-4);
  border-top: 1px solid var(--color-divider);
  background: var(--color-surface);
}

.mobile-nav.active {
  display: flex;
}

.mobile-nav a {
  padding: var(--space-3) 0;
  color: var(--color-text);
  text-decoration: none;
  font-size: var(--text-base);
  border-bottom: 1px solid var(--color-divider);
}

.mobile-nav a:last-child {
  border-bottom: none;
}

/* ===== HERO ===== */
.calc-hero {
  padding-top: calc(4.5rem + var(--space-24));
  padding-bottom: var(--space-16);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  position: relative;
  overflow: hidden;
}

[data-theme="dark"] .calc-hero {
  background: var(--color-primary-light);
  color: var(--color-text);
}

.calc-hero::before {
  content: '';
  position: absolute;
  top: 0;
  right: -10%;
  width: 50%;
  height: 100%;
  background: rgba(255, 255, 255, 0.03);
  transform: skewX(-12deg);
}

.calc-hero__eyebrow {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: var(--space-4);
  opacity: 0.7;
}

.calc-hero__title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: var(--space-6);
  max-width: 700px;
}

.calc-hero__subtitle {
  font-size: var(--text-base);
  line-height: 1.7;
  max-width: 640px;
  opacity: 0.85;
  font-weight: 300;
}

/* ===== CALCULATOR SECTION ===== */
.calc-section {
  padding: var(--space-16) 0;
  background: var(--color-bg);
}

/* Tabs */
.calc-tabs {
  display: flex;
  gap: var(--space-2);
  margin-bottom: var(--space-8);
  border-bottom: 2px solid var(--color-divider);
  padding-bottom: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.calc-tab {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  padding: var(--space-3) var(--space-5);
  border: none;
  background: none;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  white-space: nowrap;
  transition: color var(--transition-interactive), border-color var(--transition-interactive);
}

.calc-tab:hover {
  color: var(--color-text);
}

.calc-tab.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
  font-weight: 600;
}

/* Panels */
.calc-panel {
  display: none;
}

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

/* Card */
.calc-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-sm);
}

.calc-card__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.calc-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: var(--space-8);
  max-width: 72ch;
}

/* Form */
.calc-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.form-row {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.form-row--2col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-5);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-group label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
}

.form-group input,
.form-group select {
  font-family: var(--font-body);
  font-size: var(--text-base);
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
  color: var(--color-text);
  transition: border-color var(--transition-interactive), box-shadow var(--transition-interactive);
  -webkit-appearance: none;
  appearance: none;
}

.form-group select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' fill='none'%3E%3Cpath d='M1 1.5l5 5 5-5' stroke='%236B6860' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  padding-right: 2.5rem;
}

[data-theme="dark"] .form-group select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' fill='none'%3E%3Cpath d='M1 1.5l5 5 5-5' stroke='%239B9890' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(27, 67, 50, 0.1);
}

[data-theme="dark"] .form-group input:focus,
[data-theme="dark"] .form-group select:focus {
  box-shadow: 0 0 0 3px rgba(124, 184, 150, 0.15);
}

.form-group input::placeholder {
  color: var(--color-text-faint);
}

.readonly-field {
  background: var(--color-surface-2) !important;
  color: var(--color-primary) !important;
  font-weight: 700 !important;
  cursor: default;
}

/* Button */
.calc-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text-inverse);
  background: var(--color-primary);
  border: none;
  padding: var(--space-3) var(--space-8);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background var(--transition-interactive), transform var(--transition-interactive);
  align-self: flex-start;
  margin-top: var(--space-2);
}

.calc-btn:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
}

.calc-btn svg {
  width: 16px;
  height: 16px;
}

/* Results */
.calc-results {
  margin-top: var(--space-8);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-divider);
  animation: fadeIn 0.4s var(--ease-out);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.calc-results__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

/* Table */
.calc-table {
  width: 100%;
  border-collapse: collapse;
}

.calc-table th {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  padding: var(--space-3) var(--space-4);
  border-bottom: 2px solid var(--color-divider);
  text-align: left;
}

.calc-table td {
  font-size: var(--text-sm);
  color: var(--color-text);
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-divider);
}

.calc-table tbody tr:last-child td {
  border-bottom: 1px solid var(--color-divider);
}

.calc-table tfoot td {
  font-weight: 700;
  font-size: var(--text-base);
  color: var(--color-primary);
  padding: var(--space-4);
  border-bottom: none;
  border-top: 2px solid var(--color-primary);
}

.text-right {
  text-align: right;
}

.calc-note {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  margin-top: var(--space-4);
  line-height: 1.6;
  max-width: 72ch;
}

/* Sub-row (indented detail) */
.calc-table .sub-row td {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  padding-top: var(--space-1);
  padding-bottom: var(--space-1);
  border-bottom: none;
}

.calc-table .sub-row td:first-child {
  padding-left: var(--space-8);
}

/* ===== RPGT SECTION (inline, inside SPA panel) ===== */
.rpgt-inline {
  margin-top: var(--space-12);
  padding-top: var(--space-12);
  border-top: 2px solid var(--color-divider);
}

.rpgt-section {
  padding: var(--space-16) 0 var(--space-24);
  background: var(--color-surface-2);
}

.rpgt-header {
  margin-bottom: var(--space-8);
}

.rpgt-header__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.rpgt-header__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
  max-width: 72ch;
}

.rpgt-form {
  margin-bottom: 0;
}

/* RPGT Rate Table */
.rpgt-rate-table-wrap {
  margin-top: var(--space-12);
}

.rpgt-rate-table__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.rpgt-rate-table__desc {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
  line-height: 1.6;
}

.table-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.rpgt-rate-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.rpgt-rate-table th {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-text);
  padding: var(--space-4);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  text-align: center;
  border-right: 1px solid rgba(255, 255, 255, 0.1);
}

[data-theme="dark"] .rpgt-rate-table th {
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-right-color: var(--color-border);
}

.rpgt-rate-table th:first-child {
  text-align: left;
}

.rpgt-rate-table th:last-child {
  border-right: none;
}

.rpgt-rate-table .th-sub {
  font-weight: 300;
  font-size: 0.7rem;
  opacity: 0.8;
}

.rpgt-rate-table td {
  font-size: var(--text-sm);
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-divider);
  text-align: center;
  color: var(--color-text);
}

.rpgt-rate-table td:first-child {
  text-align: left;
  font-weight: 500;
}

.rpgt-rate-table tbody tr:hover {
  background: var(--color-surface-2);
}

.rpgt-rate-table .highlight-green {
  color: #2d8a56;
  font-weight: 700;
}

[data-theme="dark"] .rpgt-rate-table .highlight-green {
  color: var(--color-primary);
}

/* ===== DISCLAIMER ===== */
.disclaimer-section {
  padding: var(--space-12) 0;
  background: var(--color-bg);
}

.disclaimer-card {
  padding: var(--space-6);
  background: var(--color-accent-light);
  border-radius: var(--radius-lg);
  border-left: 4px solid var(--color-accent);
}

.disclaimer-card__title {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: var(--space-3);
}

.disclaimer-card p {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.7;
}

.disclaimer-card a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
}

.disclaimer-card a:hover {
  text-decoration: underline;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-12) 0 var(--space-6);
}

[data-theme="dark"] .footer {
  background: var(--color-surface);
  color: var(--color-text);
}

.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--space-8);
  padding-bottom: var(--space-8);
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

[data-theme="dark"] .footer__inner {
  border-bottom-color: var(--color-divider);
}

.footer__logo-name {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  display: block;
}

.footer__logo-sub {
  font-size: 0.65rem;
  font-weight: 300;
  display: block;
  opacity: 0.7;
}

.footer__tagline {
  font-size: var(--text-sm);
  opacity: 0.7;
  margin-top: var(--space-3);
}

.footer__links {
  display: flex;
  gap: var(--space-5);
}

.footer__links a {
  font-size: var(--text-sm);
  color: inherit;
  text-decoration: none;
  opacity: 0.7;
  transition: opacity var(--transition-interactive);
}

.footer__links a:hover {
  opacity: 1;
}

.footer__bottom {
  padding-top: var(--space-6);
}

.footer__bottom p {
  font-size: var(--text-xs);
  opacity: 0.5;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .header__nav {
    display: none;
  }

  .mobile-toggle {
    display: flex;
  }

  .calc-hero {
    padding-top: calc(4.5rem + var(--space-16));
    padding-bottom: var(--space-12);
  }

  .calc-hero__title {
    font-size: clamp(1.75rem, 1rem + 3vw, 2.5rem);
  }

  .calc-card {
    padding: var(--space-5);
  }

  .calc-tabs {
    gap: 0;
  }

  .calc-tab {
    padding: var(--space-3);
    font-size: var(--text-xs);
  }

  .form-row--2col {
    grid-template-columns: 1fr;
  }

  .rpgt-rate-table th,
  .rpgt-rate-table td {
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-xs);
  }

  .rpgt-rate-table .th-sub {
    display: none;
  }

  .footer__inner {
    flex-direction: column;
    gap: var(--space-6);
  }

  .footer__links {
    flex-wrap: wrap;
    gap: var(--space-3) var(--space-5);
  }

  .calc-table th,
  .calc-table td {
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-xs);
  }

  .calc-table .sub-row td:first-child {
    padding-left: var(--space-5);
  }
}