/* ---------- 1. Design tokens ---------- */
:root {
  --bg-primary: #050f0a;
  --bg-secondary: #0a1a10;
  --bg-card: #0d2018;
  --bg-card-hover: #123023;

  --green-primary: #00e676;
  --green-secondary: #00c853;
  --green-dim: #1a4d35;
  --green-glow: rgba(0, 230, 118, 0.12);

  --text-primary: #e8f5e9;
  --text-secondary: #81c784;
  --text-muted: #4caf50;

  --btn-text: #04140b;
  --header-bg: rgba(5, 15, 10, 0.88);

  --border: rgba(0, 230, 118, 0.18);
  --shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
  --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.35);

  --white: #ffffff;
  --danger: #ff5252;
  --star: #ffc107;

  --radius: 20px;
  --radius-sm: 12px;
  --radius-lg: 28px;
  --radius-pill: 999px;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --space-9: 96px;

  --container-w: 1200px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: 0.15s ease;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="light"] {
  --bg-primary: #f5faf7;
  --bg-secondary: #eaf4ee;
  --bg-card: #ffffff;
  --bg-card-hover: #f2f9f4;

  --green-primary: #00a152;
  --green-secondary: #008f47;
  --green-dim: #d7ecdf;
  --green-glow: rgba(0, 200, 83, 0.10);

  --text-primary: #0d2018;
  --text-secondary: #1a4d35;
  --text-muted: #2e7d52;

  --btn-text: #ffffff;
  --header-bg: rgba(245, 250, 247, 0.9);

  --border: rgba(0, 180, 90, 0.2);
  --shadow: 0 4px 30px rgba(13, 32, 24, 0.08);
  --shadow-sm: 0 2px 8px rgba(13, 32, 24, 0.06);
}

/* ---------- 2. Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text-primary);
  background: var(--bg-primary);
  background-image:
    radial-gradient(900px 420px at 85% -80px, var(--green-glow), transparent 70%),
    radial-gradient(700px 360px at 0% 20%, var(--green-glow), transparent 70%);
  background-repeat: no-repeat;
  transition: background-color var(--transition), color var(--transition);
}
img, svg { max-width: 100%; }
a { color: var(--green-primary); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 var(--space-3); color: var(--text-primary); }
p { margin: 0 0 var(--space-4); }
ul, ol { margin: 0 0 var(--space-4); padding-left: 1.3em; }
li { margin-bottom: 6px; }
em { font-style: normal; color: var(--green-primary); }
[hidden] { display: none !important; }
.is-hidden { display: none !important; }
section[id], div[id="results"] { scroll-margin-top: 84px; }
:focus-visible { outline: 2px solid var(--green-primary); outline-offset: 2px; }

.wrap { max-width: var(--container-w); margin: 0 auto; padding: 0 var(--space-5); }
.section { padding: var(--space-6) 0; }
.skip-link { position: absolute; left: -999px; top: 8px; background: var(--green-primary); color: var(--btn-text); padding: 8px 14px; border-radius: 8px; z-index: 200; }
.skip-link:focus { left: 8px; }

/* ---------- 3. Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 26px; border: 0; border-radius: var(--radius-pill);
  background: var(--green-primary); color: var(--btn-text);
  font: inherit; font-weight: 700; cursor: pointer; text-decoration: none;
  transition: transform var(--transition-fast), box-shadow var(--transition), background var(--transition);
}
.btn:hover { background: var(--green-secondary); transform: translateY(-1px); box-shadow: 0 6px 22px var(--green-glow); text-decoration: none; }
.btn-ghost { background: transparent; color: var(--green-primary); border: 1.5px solid var(--border); }
.btn-ghost:hover { background: var(--green-glow); box-shadow: none; }
.btn-block { flex: 1; }

/* ---------- 4. Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--header-bg);
  -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.header-in { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); min-height: 68px; }
.logo { display: inline-flex; align-items: center; gap: 8px; font-size: 1.2rem; font-weight: 800; color: var(--text-primary); text-decoration: none; letter-spacing: -0.2px; }
.logo:hover { text-decoration: none; }
.nav { display: flex; align-items: center; gap: var(--space-1); margin-left: auto; }
.nav a { color: var(--text-secondary); padding: 8px 14px; border-radius: var(--radius-pill); font-weight: 600; font-size: .95rem; transition: var(--transition-fast); }
.nav a:hover, .nav a.active { background: var(--green-glow); color: var(--green-primary); text-decoration: none; }
.header-actions { display: flex; align-items: center; gap: var(--space-2); }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 42px; height: 42px; border-radius: 50%;
  background: var(--bg-card); color: var(--green-primary);
  border: 1px solid var(--border); cursor: pointer; transition: var(--transition-fast);
}
.icon-btn:hover { background: var(--bg-card-hover); }
.icon-moon { display: none; }
[data-theme="light"] .icon-sun { display: none; }
[data-theme="light"] .icon-moon { display: block; }
.menu-btn { display: none; flex-direction: column; gap: 4px; }
.menu-btn span { width: 18px; height: 2px; background: currentColor; border-radius: 2px; transition: var(--transition-fast); }
.menu-btn[aria-expanded="true"] span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.menu-btn[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-btn[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 5. Hero ---------- */
.hero { padding: var(--space-8) 0 var(--space-6); text-align: center; }
.badge { display: inline-block; padding: 7px 16px; border-radius: var(--radius-pill); background: var(--green-glow); border: 1px solid var(--border); color: var(--green-primary); font-weight: 700; font-size: .85rem; margin-bottom: var(--space-5); }
.hero h1 { font-size: clamp(2.3rem, 6vw, 4rem); font-weight: 800; letter-spacing: -1px; margin-bottom: var(--space-4); }
.hero-lead { max-width: 780px; margin: 0 auto var(--space-3); font-size: 1.15rem; color: var(--text-primary); }
.hero-sub { max-width: 720px; margin: 0 auto var(--space-5); color: var(--text-secondary); }
.hero-btns { display: flex; flex-wrap: wrap; gap: var(--space-3); justify-content: center; margin-bottom: var(--space-6); }
.hero-stats { list-style: none; padding: 0; margin: 0 auto; display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-3); max-width: 760px; }
.hero-stats li { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 14px 8px; margin: 0; display: flex; flex-direction: column; }
.hero-stats strong { font-size: 1.4rem; color: var(--green-primary); line-height: 1.2; }
.hero-stats span { font-size: .8rem; color: var(--text-secondary); }

/* ---------- 6. Cards ---------- */
.card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: var(--space-5); box-shadow: var(--shadow-sm); }
.card-title { font-size: 1.25rem; margin-bottom: var(--space-5); }

/* ---------- 7. Tool ---------- */
.tool-grid { display: grid; grid-template-columns: minmax(0, 430px) minmax(0, 1fr); gap: var(--space-5); align-items: start; }
.form-card { position: sticky; top: 88px; }
.form-input { margin-bottom: var(--space-5); }
.form-input > label, .label-like { display: block; font-weight: 700; margin-bottom: var(--space-2); font-size: .95rem; }
.label-row { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: var(--space-2); margin-bottom: var(--space-2); }
.label-row label { font-weight: 700; font-size: .95rem; }

.input-field, .unit-select {
  width: 100%; padding: 14px 16px; font: inherit;
  color: var(--text-primary); background: var(--bg-secondary);
  border: 1.5px solid var(--border); border-radius: var(--radius-sm);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.input-field::placeholder { color: var(--text-muted); opacity: .8; }
.input-field:focus, .unit-select:focus { outline: 0; border-color: var(--green-primary); box-shadow: 0 0 0 4px var(--green-glow); }
select.input-field, .unit-select {
  appearance: none; -webkit-appearance: none; cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%2300c853' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right 14px center; padding-right: 38px;
}
option { background: var(--bg-card); color: var(--text-primary); }
input[type="date"] { color-scheme: dark; }
[data-theme="light"] input[type="date"] { color-scheme: light; }
.input-combo { display: flex; gap: var(--space-2); }
.input-combo .input-field { flex: 1; min-width: 0; }
.unit-select { width: 84px; font-weight: 700; flex: none; }

.seg { display: inline-flex; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius-pill); padding: 3px; }
.seg-btn { border: 0; background: transparent; color: var(--text-secondary); font: inherit; font-size: .8rem; font-weight: 700; padding: 5px 12px; border-radius: var(--radius-pill); cursor: pointer; }
.seg-btn.is-on { background: var(--green-primary); color: var(--btn-text); }

.pill-group { display: flex; gap: var(--space-3); }
.pill { flex: 1; cursor: pointer; margin: 0; }
.pill input { position: absolute; opacity: 0; pointer-events: none; }
.pill span { display: block; text-align: center; padding: 12px; border-radius: var(--radius-sm); background: var(--bg-secondary); border: 1.5px solid var(--border); font-weight: 700; color: var(--text-secondary); transition: var(--transition-fast); }
.pill input:checked + span { background: var(--green-glow); border-color: var(--green-primary); color: var(--green-primary); }
.pill input:focus-visible + span { outline: 2px solid var(--green-primary); outline-offset: 2px; }

.switch-row { display: flex; align-items: center; justify-content: space-between; }
.switch-row .label-like { margin: 0; }
.switch { position: relative; width: 52px; height: 28px; flex: none; cursor: pointer; }
.switch input { position: absolute; opacity: 0; width: 100%; height: 100%; margin: 0; cursor: pointer; z-index: 2; }
.switch .track { position: absolute; inset: 0; background: var(--green-dim); border: 1px solid var(--border); border-radius: var(--radius-pill); transition: var(--transition); }
.switch .thumb { position: absolute; top: 3px; left: 3px; width: 20px; height: 20px; border-radius: 50%; background: var(--white); box-shadow: var(--shadow-sm); transition: var(--transition); }
.switch input:checked ~ .track { background: var(--green-primary); }
.switch input:checked ~ .track .thumb { transform: translateX(24px); }
.switch input:focus-visible ~ .track { outline: 2px solid var(--green-primary); outline-offset: 2px; }

.form-error { color: var(--danger); font-weight: 600; font-size: .92rem; margin: 0 0 var(--space-4); }
.form-btns { display: flex; gap: var(--space-3); }

/* ---------- 8. Result ---------- */
.empty-card { text-align: center; padding: var(--space-8) var(--space-5); border-style: dashed; }
.empty-emoji { font-size: 3.5rem; margin-bottom: var(--space-3); }
.empty-card h2 { font-size: 1.4rem; }
.empty-card p { color: var(--text-secondary); max-width: 420px; margin: 0 auto; }

.result-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: var(--space-5); box-shadow: var(--shadow-sm); }
.rc-top { text-align: center; padding: var(--space-5) var(--space-4); border-radius: var(--radius); background: linear-gradient(135deg, var(--green-glow), transparent), var(--bg-secondary); border: 1px solid var(--border); margin-bottom: var(--space-4); }
.rc-label { display: block; font-size: .8rem; font-weight: 800; letter-spacing: 1.5px; text-transform: uppercase; color: var(--text-secondary); }
.rc-big { font-size: clamp(2.2rem, 6vw, 3.4rem); font-weight: 800; color: var(--green-primary); line-height: 1.2; margin: 6px 0 2px; }
.rc-alt { color: var(--text-secondary); font-weight: 600; }
.rc-meta { margin-top: var(--space-3); display: inline-block; padding: 6px 14px; border-radius: var(--radius-pill); background: var(--green-glow); border: 1px solid var(--border); font-size: .85rem; font-weight: 600; }

.rc-mid { display: grid; grid-template-columns: 190px minmax(0, 1fr); gap: var(--space-5); align-items: center; padding: var(--space-4); background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: var(--space-4); }
.donut { position: relative; width: 180px; height: 180px; margin: 0 auto; }
.donut svg { display: block; width: 100%; height: 100%; }
.donut-text { position: absolute; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; }
.donut-text strong { font-size: 2rem; line-height: 1.1; }
.donut-text span { font-size: .8rem; color: var(--text-secondary); }
.bar-row { display: grid; grid-template-columns: 110px minmax(0, 1fr) auto; gap: var(--space-3); align-items: center; margin-bottom: 10px; font-size: .92rem; }
.bar-row:last-child { margin-bottom: 0; }
.bar-row .b-label { color: var(--text-secondary); }
.bar-row .b-val { font-weight: 800; text-align: right; white-space: nowrap; }
.bar-track { height: 10px; border-radius: var(--radius-pill); background: var(--bg-primary); border: 1px solid var(--border); overflow: hidden; }
.bar-fill { height: 100%; border-radius: var(--radius-pill); background: var(--green-primary); }
.bar-fill.alt { background: var(--star); }
.bar-fill.dim { background: var(--green-secondary); opacity: .6; }

.info-rows { display: grid; gap: var(--space-3); margin-bottom: var(--space-4); }
.info-row { display: flex; align-items: center; gap: var(--space-3); padding: 14px 16px; border: 1px solid var(--border); background: var(--bg-secondary); border-radius: var(--radius-sm); font-size: .95rem; }
.info-row .ico { font-size: 1.3rem; line-height: 1; flex: none; }
.info-row strong { color: var(--text-primary); }

.chart-box, .ms-box { padding: var(--space-4); background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: var(--space-4); }
.chart-box h3, .ms-box h3 { font-size: 1.05rem; margin-bottom: var(--space-3); }
#chart svg { display: block; width: 100%; height: auto; }

.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.ms-table, .data-table { width: 100%; border-collapse: collapse; font-size: .93rem; }
.ms-table th, .ms-table td, .data-table th, .data-table td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--border); white-space: nowrap; }
.ms-table th, .data-table th { color: var(--text-secondary); font-size: .8rem; text-transform: uppercase; letter-spacing: .5px; }
.ms-table tr:last-child td, .data-table tr:last-child td { border-bottom: 0; }
.ms-table td:last-child { font-weight: 700; color: var(--green-primary); }
.ms-table tr.is-final td { font-weight: 800; background: var(--green-glow); }

.check-box { padding: 14px 16px; border-radius: var(--radius-sm); border: 1px solid var(--border); background: var(--green-glow); font-size: .93rem; }
.check-box p { margin: 0; }
.check-box strong { color: var(--green-primary); }

.export-foot { display: none; }

/* Share box */
.share-card { margin-top: var(--space-4); }
.share-card h3 { font-size: 1.1rem; margin-bottom: var(--space-4); }
.share-btns { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.chip { padding: 10px 20px; border-radius: var(--radius-pill); border: 1px solid var(--border); background: var(--bg-primary); color: var(--text-primary); font: inherit; font-weight: 700; cursor: pointer; transition: var(--transition-fast); }
.chip:hover { background: var(--bg-card-hover); border-color: var(--green-primary); }
.chip-on { background: var(--green-primary); color: var(--btn-text); border-color: var(--green-primary); }
.chip-on:hover { background: var(--green-secondary); }
.chip[disabled] { opacity: .6; cursor: wait; }

/* Export (image / pdf) layout */
.result-card.is-exporting { width: 760px; max-width: none; margin: 0; box-shadow: none; }
.result-card.is-exporting .export-foot { display: block; margin-top: var(--space-4); padding-top: var(--space-4); border-top: 1px solid var(--border); text-align: center; font-size: .9rem; color: var(--text-secondary); }
.result-card.is-exporting .export-foot p { margin: 0 0 4px; }
.result-card.is-exporting .rc-mid { grid-template-columns: 190px minmax(0, 1fr); }

/* ---------- 9. How to use ---------- */
.howto-card h2 { font-size: 1.6rem; }
.howto-card .lead { color: var(--text-secondary); }
.howto-card h3 { margin: var(--space-5) 0 var(--space-4); font-size: 1.15rem; }
.howto-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-4); }
.howto-item { background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius); padding: var(--space-5); transition: var(--transition); }
.howto-item:hover { background: var(--bg-card-hover); border-color: var(--green-primary); }
.howto-item h4 { color: var(--green-primary); font-size: 1.1rem; margin-bottom: var(--space-2); }
.howto-item p { margin: 0; color: var(--text-secondary); }

/* ---------- 10. Article ---------- */
.article { max-width: 900px; margin: 0 auto; padding: var(--space-6); }
.article h2 { font-size: 1.6rem; margin: var(--space-6) 0 var(--space-3); color: var(--green-primary); }
.article h2:first-child { margin-top: 0; }
.article h3 { font-size: 1.15rem; margin: var(--space-4) 0 var(--space-2); }
.article p, .article li { color: var(--text-primary); }
.article .table-wrap { margin: var(--space-4) 0; border: 1px solid var(--border); border-radius: var(--radius-sm); }
.article .data-table th { background: var(--bg-secondary); }

/* ---------- 11. FAQ ---------- */
.faq-wrap { max-width: 860px; margin: 0 auto; }
.section-title { text-align: center; font-size: 1.8rem; margin-bottom: var(--space-5); }
.faq-item { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-sm); margin-bottom: var(--space-3); overflow: hidden; transition: var(--transition-fast); }
.faq-item[open] { border-color: var(--green-primary); background: var(--bg-card-hover); }
.faq-item summary { list-style: none; cursor: pointer; padding: 18px 56px 18px 20px; font-weight: 700; position: relative; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; position: absolute; right: 18px; top: 50%; transform: translateY(-50%); width: 28px; height: 28px; line-height: 26px; text-align: center; border-radius: 50%; background: var(--green-glow); color: var(--green-primary); font-size: 1.3rem; font-weight: 700; }
.faq-item[open] summary::after { content: "\2212"; }
.faq-a { padding: 0 20px 6px; color: var(--text-secondary); }

/* ---------- 12. Footer ---------- */
.site-footer { margin-top: var(--space-7); padding: var(--space-7) 0 var(--space-5); background: var(--bg-secondary); border-top: 1px solid var(--border); }
.f-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1.2fr; gap: var(--space-6); }
.f-grid p { color: var(--text-secondary); margin-top: var(--space-3); font-size: .93rem; }
.f-col h4 { font-size: 1rem; color: var(--green-primary); margin-bottom: var(--space-3); }
.f-col ul { list-style: none; padding: 0; margin: 0; }
.f-col li { margin-bottom: 8px; }
.f-col a { color: var(--text-secondary); font-size: .93rem; }
.f-col a:hover { color: var(--green-primary); }
.f-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-3); margin-top: var(--space-6); padding-top: var(--space-4); border-top: 1px solid var(--border); font-size: .9rem; color: var(--text-secondary); }
.f-bottom p { margin: 0; }
.f-links { display: flex; flex-wrap: wrap; gap: var(--space-4); }
.f-links a { color: var(--text-secondary); }
.f-links a:hover { color: var(--green-primary); }
.f-note { margin: var(--space-4) 0 0; font-size: .85rem; color: var(--text-muted); }

/* Toast */
.toast { position: fixed; left: 50%; bottom: 28px; transform: translate(-50%, 20px); opacity: 0; pointer-events: none; background: var(--green-primary); color: var(--btn-text); padding: 12px 22px; border-radius: var(--radius-pill); font-weight: 700; box-shadow: var(--shadow); z-index: 300; transition: var(--transition); }
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 13. Responsive ---------- */
@media (max-width: 1000px) {
  .tool-grid { grid-template-columns: 1fr; }
  .form-card { position: static; }
  .f-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 820px) {
  .menu-btn { display: inline-flex; }
  .nav {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 2px; margin: 0;
    padding: var(--space-3) var(--space-5) var(--space-4);
    background: var(--bg-secondary); border-bottom: 1px solid var(--border);
  }
  .nav.open { display: flex; }
  .nav a { padding: 12px 14px; }
  .header-actions { margin-left: auto; }
  .header-in { position: relative; }
}
@media (max-width: 640px) {
  .wrap { padding: 0 var(--space-4); }
  .hero { padding-top: var(--space-7); }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .howto-grid { grid-template-columns: 1fr; }
  .rc-mid { grid-template-columns: 1fr; }
  .bar-row { grid-template-columns: 92px minmax(0, 1fr) auto; font-size: .85rem; }
  .article { padding: var(--space-5) var(--space-4); }
  .card, .result-card { padding: var(--space-4); }
  .f-grid { grid-template-columns: 1fr; gap: var(--space-5); }
  .form-btns { flex-direction: column; }
  .logo { font-size: 1.05rem; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}