@charset "UTF-8";
/* ============================================================
   最佳燃脂心跳計算器 ─ 樣式表
   配色：白 × 粉紅（玫瑰金細節）
   支援：桌機 / 平板 / 手機，含列印樣式與 reduced-motion
   ============================================================ */

/* ── 1. 設計權杖 ─────────────────────────────────────────── */
:root {
    --pink-50:  #fff7fa;
    --pink-100: #ffeaf1;
    --pink-200: #ffd6e2;
    --pink-300: #ffb8cd;
    --pink-400: #ff92ae;
    --pink-500: #f4688f;
    --pink-600: #dd4173;
    --pink-700: #b62c5b;
    --pink-900: #6d2038;

    --gold-300: #e6c79c;
    --gold-500: #c9a06a;

    --ink:      #2b1f27;
    --ink-soft: #6f5c66;
    --ink-mute: #96838d;

    --white: #ffffff;
    --paper: #fffbfc;
    --line:        rgba(221, 65, 115, 0.14);
    --line-strong: rgba(221, 65, 115, 0.26);

    --radius-sm: 12px;
    --radius-md: 18px;
    --radius-lg: 26px;
    --radius-xl: 34px;
    --radius-pill: 999px;

    --shadow-xs: 0 2px 6px rgba(176, 52, 96, 0.06);
    --shadow-sm: 0 6px 18px rgba(176, 52, 96, 0.08);
    --shadow-md: 0 16px 40px rgba(176, 52, 96, 0.10);
    --shadow-lg: 0 30px 70px rgba(150, 40, 80, 0.14);
    --shadow-pink: 0 14px 30px rgba(221, 65, 115, 0.28);

    --sans:  "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", "Helvetica Neue", Arial, sans-serif;
    --serif: "Noto Serif TC", "Songti TC", "PingFang TC", Georgia, "Times New Roman", serif;

    --ease: cubic-bezier(0.22, 0.8, 0.28, 1);
    --maxw: 1160px;
}

/* ── 2. 基礎 ─────────────────────────────────────────────── */
*,
*::before,
*::after { box-sizing: border-box; }

html {
    -webkit-text-size-adjust: 100%;
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: var(--sans);
    font-size: 16px;
    line-height: 1.75;
    color: var(--ink);
    background-color: var(--white);
    background-image:
        radial-gradient(60rem 34rem at 12% -8%, rgba(255, 214, 226, 0.55), transparent 60%),
        radial-gradient(48rem 30rem at 92% 4%, rgba(255, 234, 241, 0.9), transparent 62%),
        radial-gradient(52rem 40rem at 50% 108%, rgba(255, 214, 226, 0.4), transparent 60%);
    background-attachment: fixed;
    overflow-x: hidden;
}

img, svg { max-width: 100%; }

a { color: var(--pink-700); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
    font-family: var(--serif);
    font-weight: 700;
    line-height: 1.35;
    letter-spacing: 0.01em;
    margin: 0 0 0.6em;
    color: var(--ink);
}

p { margin: 0 0 1em; }

:focus-visible {
    outline: 3px solid rgba(244, 104, 143, 0.55);
    outline-offset: 3px;
    border-radius: 6px;
}

.visually-hidden {
    position: absolute !important;
    width: 1px; height: 1px;
    padding: 0; margin: -1px;
    overflow: hidden; clip: rect(0 0 0 0);
    white-space: nowrap; border: 0;
}

.skip-link {
    position: absolute;
    left: 50%; top: -60px;
    transform: translateX(-50%);
    z-index: 99;
    padding: 10px 20px;
    background: var(--white);
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
    box-shadow: var(--shadow-sm);
    transition: top 0.2s var(--ease);
}
.skip-link:focus { top: 0; }

/* ── 3. 版面容器 ─────────────────────────────────────────── */
.wrap {
    width: 100%;
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 22px;
}

.section { padding: 56px 0; }
.section--tight { padding: 34px 0; }

.section-title {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: clamp(1.35rem, 2.4vw, 1.75rem);
    margin-bottom: 6px;
}
.section-title::before {
    content: "";
    width: 26px; height: 1px;
    background: linear-gradient(90deg, transparent, var(--gold-500));
    flex: none;
}
.section-lead {
    color: var(--ink-soft);
    max-width: 62ch;
    margin-bottom: 26px;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--sans);
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 0.32em;
    text-transform: uppercase;
    color: var(--pink-700);
    margin-bottom: 14px;
}
.eyebrow::before {
    content: "";
    width: 34px; height: 1px;
    background: linear-gradient(90deg, var(--pink-400), transparent);
}

/* ── 4. 頁首 ─────────────────────────────────────────────── */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.82);
    backdrop-filter: blur(14px) saturate(140%);
    -webkit-backdrop-filter: blur(14px) saturate(140%);
    border-bottom: 1px solid var(--line);
}

.site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
    min-height: 68px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: inherit;
    text-decoration: none;
}
.brand:hover { text-decoration: none; }

.brand__mark {
    width: 40px; height: 40px;
    display: grid;
    place-items: center;
    border-radius: 13px;
    background: linear-gradient(145deg, var(--pink-400), var(--pink-600));
    box-shadow: var(--shadow-pink);
    flex: none;
}
.brand__mark svg { width: 22px; height: 22px; display: block; }

.brand__text { display: flex; flex-direction: column; line-height: 1.25; }
.brand__name {
    font-family: var(--serif);
    font-weight: 700;
    font-size: 1.02rem;
    letter-spacing: 0.02em;
}
.brand__sub {
    font-size: 0.66rem;
    letter-spacing: 0.28em;
    text-transform: uppercase;
    color: var(--ink-mute);
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 22px;
    font-size: 0.9rem;
}
.site-nav a { color: var(--ink-soft); }
.site-nav a:hover { color: var(--pink-700); }

/* ── 5. Hero ─────────────────────────────────────────────── */
.hero { padding: 62px 0 18px; }

.hero__grid {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: 46px;
    align-items: center;
}

.hero h1 {
    font-size: clamp(2rem, 4.6vw, 3.15rem);
    line-height: 1.22;
    margin-bottom: 18px;
}
.hero h1 .accent {
    background: linear-gradient(100deg, var(--pink-600), var(--gold-500) 92%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: inline-block;
}

.hero__lead {
    font-size: 1.06rem;
    color: var(--ink-soft);
    max-width: 46ch;
    margin-bottom: 26px;
}

.hero__actions { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }

.hero__facts {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
    margin-top: 34px;
    padding-top: 26px;
    border-top: 1px solid var(--line);
}
.hero__fact strong {
    display: block;
    font-family: var(--serif);
    font-size: 1.42rem;
    color: var(--pink-700);
    font-variant-numeric: tabular-nums;
}
.hero__fact span { font-size: 0.82rem; color: var(--ink-mute); }

/* 心跳裝飾卡 */
.pulse-card {
    position: relative;
    padding: 30px 30px 26px;
    border-radius: var(--radius-xl);
    background: linear-gradient(160deg, #fff 0%, var(--pink-50) 62%, var(--pink-100) 100%);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}
.pulse-card::after {
    content: "";
    position: absolute;
    inset: auto -40px -60px auto;
    width: 210px; height: 210px;
    border-radius: 50%;
    background: radial-gradient(circle at 30% 30%, rgba(255, 146, 174, 0.45), transparent 70%);
}
.pulse-card__label {
    font-size: 0.74rem;
    letter-spacing: 0.26em;
    text-transform: uppercase;
    color: var(--pink-700);
    margin-bottom: 6px;
}
.pulse-card__value {
    font-family: var(--serif);
    font-size: clamp(2.4rem, 5vw, 3.4rem);
    line-height: 1.05;
    font-variant-numeric: tabular-nums;
    color: var(--pink-700);
}
.pulse-card__unit { font-size: 0.95rem; color: var(--ink-mute); letter-spacing: 0.05em; }
.pulse-card__note { font-size: 0.85rem; color: var(--ink-soft); margin: 12px 0 0; }

.pulse-line { display: block; width: 100%; height: 62px; margin-top: 14px; }
.pulse-line path {
    fill: none;
    stroke: var(--pink-500);
    stroke-width: 2.4;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-dasharray: 420;
    stroke-dashoffset: 420;
    animation: draw 3.4s var(--ease) infinite;
}
@keyframes draw {
    0%   { stroke-dashoffset: 420; }
    55%  { stroke-dashoffset: 0; }
    100% { stroke-dashoffset: -420; }
}

/* ── 6. 按鈕與標籤 ───────────────────────────────────────── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 9px;
    padding: 13px 28px;
    border-radius: var(--radius-pill);
    border: 1px solid transparent;
    font-family: var(--sans);
    font-size: 0.95rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    cursor: pointer;
    transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease),
                background-color 0.18s var(--ease), color 0.18s var(--ease);
}
.btn svg { width: 18px; height: 18px; }

.btn--primary {
    color: #fff;
    background: linear-gradient(135deg, var(--pink-500), var(--pink-600));
    box-shadow: var(--shadow-pink);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 18px 36px rgba(221, 65, 115, 0.34); }
.btn--primary:active { transform: translateY(0); }

.btn--ghost {
    color: var(--pink-700);
    background: rgba(255, 255, 255, 0.9);
    border-color: var(--line-strong);
    box-shadow: var(--shadow-xs);
}
.btn--ghost:hover { background: var(--pink-50); transform: translateY(-2px); }

.btn--text {
    padding: 10px 16px;
    background: transparent;
    color: var(--ink-soft);
    border-color: transparent;
}
.btn--text:hover { color: var(--pink-700); background: var(--pink-50); }

.btn[disabled] { opacity: 0.55; cursor: progress; transform: none; }

/* ── 7. 卡片 ─────────────────────────────────────────────── */
.card {
    background: rgba(255, 255, 255, 0.94);
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.card--padded { padding: 30px 32px; }

.card--accent {
    background:
        linear-gradient(rgba(255, 255, 255, 0.96), rgba(255, 255, 255, 0.96)) padding-box,
        linear-gradient(135deg, var(--pink-400), var(--gold-300) 55%, var(--pink-200)) border-box;
    border: 1px solid transparent;
}

/* ── 8. 計算表單 ─────────────────────────────────────────── */
.calc { position: relative; }

.calc__head {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    justify-content: space-between;
    gap: 14px;
    margin-bottom: 22px;
}
.calc__head h2 { margin: 0; font-size: clamp(1.25rem, 2.2vw, 1.6rem); }

.calc__grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 26px 34px;
}

.field { display: flex; flex-direction: column; gap: 8px; min-width: 0; }

.field__label {
    display: flex;
    align-items: baseline;
    gap: 8px;
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--ink);
}
.field__hint {
    font-size: 0.76rem;
    font-weight: 400;
    color: var(--ink-mute);
}

.input-shell {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 4px 16px 4px 6px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-md);
    background: var(--white);
    box-shadow: var(--shadow-xs);
    transition: border-color 0.18s var(--ease), box-shadow 0.18s var(--ease);
}
.input-shell:focus-within {
    border-color: var(--pink-400);
    box-shadow: 0 0 0 4px rgba(255, 146, 174, 0.18);
}

.field input[type="number"],
.field input[type="text"] {
    flex: 1 1 auto;
    min-width: 0;
    width: 100%;
    border: 0;
    padding: 12px 6px;
    font-family: var(--sans);
    font-size: 1.12rem;
    font-variant-numeric: tabular-nums;
    color: var(--ink);
    background: transparent;
}
.field input:focus { outline: none; }
.field input::placeholder { color: var(--ink-mute); opacity: 0.75; }

.input-unit {
    font-size: 0.82rem;
    color: var(--ink-mute);
    white-space: nowrap;
}

.field--invalid .input-shell { border-color: var(--pink-600); }

.field__error {
    font-size: 0.78rem;
    color: var(--pink-700);
    min-height: 1.1em;
}

/* 強度雙滑桿 */
.intensity { grid-column: 1 / -1; }

.intensity__readout {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    background: linear-gradient(120deg, var(--pink-50), var(--pink-100));
    border: 1px solid var(--line);
    margin-bottom: 10px;
}
.intensity__readout strong {
    font-family: var(--serif);
    font-size: 1.3rem;
    color: var(--pink-700);
    font-variant-numeric: tabular-nums;
    line-height: 1;
}
.intensity__readout span { font-size: 0.82rem; color: var(--ink-soft); }

.range-pair { display: grid; gap: 14px; }

.range {
    display: grid;
    grid-template-columns: 58px minmax(0, 1fr) 66px;
    align-items: center;
    gap: 12px;
}
.range__tag {
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--ink-soft);
    letter-spacing: 0.04em;
}
.range__value {
    font-family: var(--serif);
    font-size: 1.02rem;
    font-variant-numeric: tabular-nums;
    text-align: right;
    color: var(--pink-700);
}

input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 26px;
    background: transparent;
    cursor: pointer;
    margin: 0;
}
input[type="range"]::-webkit-slider-runnable-track {
    height: 6px;
    border-radius: var(--radius-pill);
    background: linear-gradient(90deg, var(--pink-400) 0%, var(--pink-400) var(--fill, 40%),
                                        var(--pink-100) var(--fill, 40%), var(--pink-100) 100%);
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 22px; height: 22px;
    margin-top: -8px;
    border-radius: 50%;
    background: #fff;
    border: 2px solid var(--pink-500);
    box-shadow: 0 3px 10px rgba(221, 65, 115, 0.35);
    transition: transform 0.15s var(--ease);
}
input[type="range"]:active::-webkit-slider-thumb { transform: scale(1.12); }
input[type="range"]::-moz-range-track {
    height: 6px;
    border-radius: var(--radius-pill);
    background: var(--pink-100);
}
input[type="range"]::-moz-range-progress {
    height: 6px;
    border-radius: var(--radius-pill);
    background: var(--pink-400);
}
input[type="range"]::-moz-range-thumb {
    width: 20px; height: 20px;
    border-radius: 50%;
    background: #fff;
    border: 2px solid var(--pink-500);
    box-shadow: 0 3px 10px rgba(221, 65, 115, 0.35);
}

.chips { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 6px; }

.chip {
    padding: 8px 16px;
    border-radius: var(--radius-pill);
    border: 1px solid var(--line-strong);
    background: rgba(255, 255, 255, 0.9);
    color: var(--ink-soft);
    font-family: var(--sans);
    font-size: 0.83rem;
    cursor: pointer;
    transition: background-color 0.16s var(--ease), color 0.16s var(--ease),
                border-color 0.16s var(--ease), transform 0.16s var(--ease);
}
.chip:hover { border-color: var(--pink-400); color: var(--pink-700); background: var(--pink-50); transform: translateY(-1px); }
.chip[aria-pressed="true"] {
    background: linear-gradient(135deg, var(--pink-500), var(--pink-600));
    border-color: transparent;
    color: #fff;
    box-shadow: var(--shadow-pink);
}

.calc__actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 12px;
    margin-top: 28px;
    padding-top: 24px;
    border-top: 1px solid var(--line);
}
.calc__actions .spacer { flex: 1 1 auto; }

/* ── 9. 提示訊息 ─────────────────────────────────────────── */
.alert {
    display: flex;
    gap: 12px;
    padding: 14px 18px;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    line-height: 1.65;
    margin-bottom: 18px;
}
.alert--warn {
    background: #fff9ec;
    border: 1px solid rgba(201, 160, 106, 0.45);
    color: #7a5a24;
}
.alert--error {
    background: var(--pink-100);
    border: 1px solid var(--line-strong);
    color: var(--pink-900);
}
.alert__icon { flex: none; }

.alerts { margin-bottom: 6px; }
.alerts:empty { display: none; }
.alerts__actions { display: flex; flex-wrap: wrap; gap: 10px; margin: -8px 0 18px; }

/* ── 10. 結果區 ──────────────────────────────────────────── */
.results { position: relative; }
.results[hidden] { display: none; }

.results__head {
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 22px;
}
.results__head h2 { margin: 0; font-size: clamp(1.3rem, 2.4vw, 1.7rem); }

.results__meta {
    margin: 0;
    font-size: 0.86rem;
    color: var(--ink-mute);
    font-variant-numeric: tabular-nums;
}

.results__footnote {
    font-size: 0.82rem;
    color: var(--ink-mute);
    margin: 18px 0 0;
}

.results__toolbar { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }

.empty-state {
    padding: 46px 32px;
    text-align: center;
    border-radius: var(--radius-lg);
    border: 1px dashed var(--line-strong);
    background: rgba(255, 255, 255, 0.7);
    color: var(--ink-soft);
}
.empty-state strong {
    display: block;
    font-family: var(--serif);
    font-size: 1.15rem;
    color: var(--ink);
    margin-bottom: 6px;
}

/* 摘要數字 */
.stats {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 16px;
    margin-bottom: 26px;
}
.stat {
    padding: 20px 22px;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-sm);
}
.stat__label {
    display: block;
    font-size: 0.75rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--ink-mute);
    margin-bottom: 6px;
}
.stat__value {
    display: block;
    font-family: var(--serif);
    font-size: clamp(1.5rem, 2.6vw, 2rem);
    line-height: 1.1;
    color: var(--pink-700);
    font-variant-numeric: tabular-nums;
}
.stat__value small { font-size: 0.85rem; color: var(--ink-mute); margin-left: 3px; }
.stat__hint { font-size: 0.78rem; color: var(--ink-soft); }

.stat--hero {
    background: linear-gradient(140deg, var(--pink-500), var(--pink-600));
    border-color: transparent;
    box-shadow: var(--shadow-pink);
}
.stat--hero .stat__label,
.stat--hero .stat__value,
.stat--hero .stat__hint,
.stat--hero .stat__value small { color: #fff; }
.stat--hero .stat__label { opacity: 0.88; }
.stat--hero .stat__value small { opacity: 0.9; }

/* 方法卡片 */
.methods {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
    margin-bottom: 30px;
}

.method {
    position: relative;
    padding: 26px 28px 24px;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.96);
    border: 1px solid transparent;
    box-shadow: var(--shadow-md);
    overflow: hidden;
}
.method--rose {
    background:
        linear-gradient(rgba(255, 255, 255, 0.97), rgba(255, 255, 255, 0.97)) padding-box,
        linear-gradient(140deg, var(--pink-500), var(--gold-300)) border-box;
    border: 1px solid transparent;
}
.method--blush {
    background:
        linear-gradient(rgba(255, 255, 255, 0.97), rgba(255, 255, 255, 0.97)) padding-box,
        linear-gradient(140deg, var(--pink-300), var(--pink-100)) border-box;
    border: 1px solid transparent;
}
.method--muted { opacity: 0.85; }

.method__head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 16px;
}
.method__title { margin: 0; font-size: 1.2rem; }
.method__en {
    margin: 2px 0 0;
    font-size: 0.7rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--ink-mute);
}
.method__badge {
    flex: none;
    padding: 6px 13px;
    border-radius: var(--radius-pill);
    font-size: 0.74rem;
    font-weight: 600;
    color: var(--pink-700);
    background: var(--pink-100);
    border: 1px solid var(--line);
    white-space: nowrap;
}
.method--rose .method__badge {
    color: #fff;
    background: linear-gradient(135deg, var(--pink-500), var(--pink-600));
    border-color: transparent;
}

.method__bpm { display: flex; align-items: baseline; gap: 8px; margin-bottom: 4px; }
.method__bpm-value {
    font-family: var(--serif);
    font-size: clamp(2rem, 4.2vw, 2.7rem);
    line-height: 1.05;
    color: var(--pink-700);
    font-variant-numeric: tabular-nums;
    letter-spacing: -0.01em;
}
.method__bpm-unit { font-size: 0.9rem; color: var(--ink-mute); letter-spacing: 0.08em; }

.method__range { font-size: 0.86rem; color: var(--ink-soft); margin-bottom: 14px; }

.method__formula {
    margin: 0 0 16px;
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    background: var(--pink-50);
    border: 1px dashed var(--line-strong);
    font-family: var(--serif);
    font-size: 0.88rem;
    color: var(--pink-900);
    word-break: break-word;
}

.method__zones { list-style: none; margin: 0 0 14px; padding: 0; display: grid; gap: 7px; }

.zone-row {
    display: grid;
    grid-template-columns: 10px minmax(0, 1fr) auto auto;
    align-items: center;
    gap: 10px;
    padding: 9px 12px;
    border-radius: var(--radius-sm);
    font-size: 0.86rem;
    color: var(--ink-soft);
    background: rgba(255, 247, 250, 0.85);
}
.zone-row--fat {
    background: linear-gradient(120deg, var(--pink-100), var(--pink-50));
    color: var(--ink);
    font-weight: 600;
    box-shadow: inset 0 0 0 1px var(--line-strong);
}
.zone-row__dot { width: 9px; height: 9px; border-radius: 50%; }
.tone-1 { background: #ffd9e4; }
.tone-2 { background: var(--pink-400); }
.tone-3 { background: var(--pink-500); }
.tone-4 { background: var(--pink-600); }
.tone-5 { background: var(--pink-900); }
.zone-row__pct { font-variant-numeric: tabular-nums; color: var(--ink-mute); font-size: 0.8rem; }
.zone-row--fat .zone-row__pct { color: var(--pink-700); }
.zone-row__bpm {
    font-family: var(--serif);
    font-variant-numeric: tabular-nums;
    color: var(--pink-700);
    white-space: nowrap;
}

.method__note { margin: 0; font-size: 0.8rem; color: var(--ink-mute); line-height: 1.6; }

.method__missing {
    padding: 18px;
    border-radius: var(--radius-md);
    background: var(--pink-50);
    border: 1px dashed var(--line-strong);
    color: var(--ink-soft);
    font-size: 0.88rem;
}

/* ── 11. 強度尺規 ────────────────────────────────────────── */
.zone-chart {
    padding: 24px 28px 20px;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-sm);
    margin-bottom: 30px;
}
.zone-chart__head {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 16px;
}
.zone-chart__head h3 { margin: 0; font-size: 1.02rem; }
.zone-chart__head span { font-size: 0.8rem; color: var(--ink-mute); }

.zone-chart__track {
    position: relative;
}

.zone-chart__segs {
    display: flex;
    height: 40px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: inset 0 0 0 1px var(--line);
}
.zone-chart__seg {
    flex: 1 1 0;
    display: grid;
    place-items: center;
    font-size: 0.68rem;
    color: rgba(43, 31, 39, 0.72);
    letter-spacing: 0.04em;
}
.zone-chart__seg--1 { background: #ffdfe8; }
.zone-chart__seg--2 { background: linear-gradient(180deg, #ffb4cb, #ffa2bf); color: #6d2038; }
.zone-chart__seg--3 { background: linear-gradient(180deg, #ff92ae, #f4688f); color: #fff; }
.zone-chart__seg--4 { background: linear-gradient(180deg, #f4688f, #dd4173); color: #fff; }
.zone-chart__seg--5 { background: linear-gradient(180deg, #b62c5b, #8d2049); color: #fff; }

.zone-chart__marker {
    position: absolute;
    top: -5px;
    bottom: -5px;
    border: 2px solid var(--pink-700);
    border-radius: 13px;
    background: rgba(255, 255, 255, 0.28);
    box-shadow: 0 6px 16px rgba(109, 32, 56, 0.25);
    pointer-events: none;
    transition: left 0.35s var(--ease), width 0.35s var(--ease);
}
.zone-chart__marker::after {
    content: attr(data-label);
    position: absolute;
    top: -26px;
    left: 50%;
    transform: translateX(-50%);
    padding: 2px 10px;
    border-radius: var(--radius-pill);
    background: var(--pink-700);
    color: #fff;
    font-size: 0.68rem;
    letter-spacing: 0.06em;
    white-space: nowrap;
}

.zone-chart__scale { position: relative; height: 22px; margin-top: 10px; }
.zone-chart__tick {
    position: absolute;
    transform: translateX(-50%);
    font-size: 0.7rem;
    color: var(--ink-mute);
    font-variant-numeric: tabular-nums;
}

.zone-chart__caption {
    margin: 14px 0 0;
    font-size: 0.8rem;
    color: var(--ink-soft);
}

/* ── 12. 對照表格 ────────────────────────────────────────── */
.table-card {
    border-radius: var(--radius-lg);
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.96);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    margin-bottom: 30px;
}
.table-card__head {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: space-between;
    gap: 10px;
    padding: 20px 26px 12px;
}
.table-card__head h3 { margin: 0; font-size: 1.02rem; }
.table-card__head span { font-size: 0.8rem; color: var(--ink-mute); }

.table-scroll { overflow-x: auto; }

table.zones {
    width: 100%;
    min-width: 640px;
    border-collapse: collapse;
    font-size: 0.9rem;
}
table.zones caption {
    caption-side: bottom;
    padding: 14px 26px 20px;
    text-align: left;
    font-size: 0.78rem;
    color: var(--ink-mute);
}
table.zones th,
table.zones td {
    padding: 13px 18px;
    text-align: left;
    border-bottom: 1px solid var(--line);
    vertical-align: middle;
}
table.zones thead th {
    background: var(--pink-50);
    font-family: var(--sans);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    color: var(--pink-900);
    white-space: nowrap;
}
table.zones tbody tr:nth-child(even) { background: #fffafc; }
table.zones tbody tr:hover { background: var(--pink-50); }
table.zones td.num {
    font-family: var(--serif);
    font-variant-numeric: tabular-nums;
    color: var(--pink-700);
    white-space: nowrap;
}
table.zones tr.is-fat { background: linear-gradient(100deg, var(--pink-100), var(--pink-50)); }
table.zones tr.is-fat td { font-weight: 600; }
table.zones .zone-name { display: inline-flex; align-items: center; gap: 9px; white-space: nowrap; }
table.zones tbody td:last-child,
table.zones thead th:last-child { text-align: right; }

.tag {
    display: inline-block;
    margin-left: 8px;
    padding: 2px 9px;
    border-radius: var(--radius-pill);
    font-size: 0.68rem;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, var(--pink-500), var(--pink-600));
    vertical-align: middle;
}
.tag--soft {
    background: var(--pink-100);
    color: var(--pink-700);
}

/* ── 13. 最近計算（選用 DB）──────────────────────────────── */
.recent {
    padding: 22px 26px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.92);
    box-shadow: var(--shadow-sm);
}
.recent h3 { margin: 0 0 12px; font-size: 1rem; }
.recent ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
.recent li {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 14px;
    align-items: baseline;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    background: var(--pink-50);
    font-size: 0.84rem;
    color: var(--ink-soft);
    font-variant-numeric: tabular-nums;
}
.recent li strong { color: var(--pink-700); font-family: var(--serif); }

/* ── 14. 公式說明 ────────────────────────────────────────── */
.explain {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
}

.formula-card {
    padding: 26px 28px;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-sm);
}
.formula-card h3 {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
    font-size: 1.08rem;
}
.formula-card__formula {
    margin: 0 0 14px;
    padding: 16px 18px;
    border-radius: var(--radius-md);
    background: linear-gradient(120deg, var(--pink-50), var(--pink-100));
    border: 1px solid var(--line);
    font-family: var(--serif);
    font-size: 0.98rem;
    color: var(--pink-900);
    line-height: 1.9;
    word-break: break-word;
}
.formula-card__formula code {
    font-family: var(--serif);
    background: transparent;
    color: inherit;
}
.formula-card p:last-child { margin-bottom: 0; }
.formula-card__list {
    margin: 0;
    padding-left: 1.15em;
    font-size: 0.88rem;
    color: var(--ink-soft);
}
.formula-card__list li { margin-bottom: 6px; }

/* ── 15. FAQ ─────────────────────────────────────────────── */
.faq { display: grid; gap: 12px; max-width: 900px; }

.faq details {
    border-radius: var(--radius-md);
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.94);
    box-shadow: var(--shadow-xs);
    overflow: hidden;
}
.faq summary {
    position: relative;
    padding: 16px 52px 16px 22px;
    cursor: pointer;
    font-family: var(--serif);
    font-size: 1rem;
    color: var(--ink);
    list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
    content: "＋";
    position: absolute;
    right: 20px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--pink-600);
    font-size: 1.05rem;
    transition: transform 0.24s var(--ease);
}
.faq details[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq details[open] summary { color: var(--pink-700); }
.faq__body {
    padding: 0 22px 18px;
    font-size: 0.9rem;
    color: var(--ink-soft);
    line-height: 1.8;
}
.faq__body p:last-child { margin-bottom: 0; }

/* ── 16. 免責與頁尾 ──────────────────────────────────────── */
.disclaimer {
    padding: 20px 24px;
    border-radius: var(--radius-lg);
    border: 1px solid rgba(201, 160, 106, 0.4);
    background: linear-gradient(120deg, #fffdf8, var(--pink-50));
    font-size: 0.84rem;
    color: var(--ink-soft);
    line-height: 1.8;
}
.disclaimer strong { color: var(--ink); }

.site-footer {
    margin-top: 40px;
    padding: 40px 0 34px;
    border-top: 1px solid var(--line);
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.5), rgba(255, 246, 249, 0.9));
}
.site-footer__inner {
    display: flex;
    flex-wrap: wrap;
    gap: 22px;
    align-items: center;
    justify-content: space-between;
}
.site-footer__meta { font-size: 0.8rem; color: var(--ink-mute); margin: 0; }
.site-footer__links { display: flex; flex-wrap: wrap; gap: 18px; font-size: 0.85rem; }
.site-footer__links a { color: var(--ink-soft); }
.site-footer__links a:hover { color: var(--pink-700); }

/* ── 17. 進場動畫 ────────────────────────────────────────── */
.reveal {
    opacity: 0;
    transform: translateY(14px);
    animation: reveal 0.6s var(--ease) forwards;
}
.reveal--2 { animation-delay: 0.08s; }
.reveal--3 { animation-delay: 0.16s; }
@keyframes reveal {
    to { opacity: 1; transform: none; }
}

/* ── 18. 工具類別 ────────────────────────────────────────── */
.no-js-only { display: none; }
html.no-js .no-js-only { display: block; }
html:not(.no-js) .no-js-only { display: none !important; }
.is-hidden { display: none !important; }

/* ── 19. 響應式 ──────────────────────────────────────────── */
@media (max-width: 1024px) {
    .hero__grid { grid-template-columns: 1fr; gap: 34px; }
    .pulse-card { max-width: 520px; }
    .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 880px) {
    .methods,
    .explain,
    .calc__grid { grid-template-columns: 1fr; }
    .site-nav { display: none; }
    .section { padding: 44px 0; }
}

@media (max-width: 600px) {
    body { font-size: 15.5px; }
    .wrap { padding: 0 16px; }
    .card--padded,
    .method,
    .formula-card,
    .zone-chart,
    .zone-chart { padding: 22px 20px; }
    .hero { padding: 40px 0 10px; }
    .hero__facts { grid-template-columns: 1fr; gap: 12px; }
    .stats { grid-template-columns: 1fr; }
    .range { grid-template-columns: 52px minmax(0, 1fr) 58px; gap: 8px; }
    .calc__actions .btn { flex: 1 1 100%; }
    .table-card__head { padding: 18px 18px 10px; }
    .zone-chart__marker::after { display: none; }
    .results__toolbar { width: 100%; }
}

/* ── 20. 無障礙：減少動態 ────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
        scroll-behavior: auto !important;
    }
    .reveal { opacity: 1; transform: none; }
    .pulse-line path { stroke-dashoffset: 0; }
}

/* ── 21. 列印 ────────────────────────────────────────────── */
@media print {
    :root { --shadow-md: none; --shadow-sm: none; --shadow-lg: none; }
    body {
        background: #fff;
        background-image: none;
        color: #000;
        font-size: 12pt;
    }
    .site-header,
    .site-nav,
    .hero__actions,
    .calc__actions,
    .results__toolbar,
    .site-footer__links,
    .pulse-card,
    .faq { display: none !important; }
    .card,
    .method,
    .stat,
    .table-card,
    .zone-chart,
    .formula-card {
        box-shadow: none;
        border: 1px solid #ddd;
        background: #fff !important;
        break-inside: avoid;
    }
    .method__bpm-value,
    .stat__value,
    table.zones td.num { color: #111 !important; -webkit-text-fill-color: currentColor; }
    .stat--hero { background: #f3d7e0 !important; }
    .stat--hero .stat__label,
    .stat--hero .stat__value,
    .stat--hero .stat__hint,
    .stat--hero .stat__value small { color: #111 !important; }
    .zone-chart__seg { color: #111 !important; }
    .zone-chart__marker::after { display: none; }
    a[href]::after { content: " (" attr(href) ")"; font-size: 9pt; color: #555; }
    .results[hidden] { display: block !important; }
    .section { padding: 14px 0; }
    .no-js-only { display: none !important; }
}

/* ── 22. 心率區間說明清單 ───────────────────────────────── */
.zone-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
}
.zone-item {
    display: flex;
    gap: 14px;
    padding: 20px 22px;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.94);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-xs);
}
.zone-item__tone {
    flex: none;
    width: 12px;
    height: 12px;
    margin-top: 7px;
    border-radius: 50%;
    box-shadow: 0 0 0 4px rgba(255, 214, 226, 0.55);
}
.zone-item__name {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    margin: 0 0 6px;
    font-size: 1rem;
}
.zone-item__summary {
    margin: 0;
    font-size: 0.87rem;
    font-weight: 600;
    color: var(--ink);
}
.zone-item__detail {
    margin: 5px 0 0;
    font-size: 0.82rem;
    color: var(--ink-mute);
    line-height: 1.7;
}

@media (max-width: 880px) {
    .zone-list { grid-template-columns: 1fr; }
}

/* ── 23. 語言切換器 ────────────────────────────────────── */
.site-header__tools {
    display: flex;
    align-items: center;
    gap: 18px;
}

.lang-switch {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px;
    border-radius: var(--radius-pill);
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.85);
    box-shadow: var(--shadow-xs);
}
.lang-switch__label {
    padding: 0 8px;
    font-size: 0.7rem;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--ink-mute);
}
.lang-switch__option {
    padding: 6px 14px;
    border-radius: var(--radius-pill);
    font-family: var(--sans);
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--ink-soft);
    text-decoration: none;
    transition: background-color 0.16s var(--ease), color 0.16s var(--ease);
}
.lang-switch__option:hover {
    color: var(--pink-700);
    background: var(--pink-50);
    text-decoration: none;
}
.lang-switch__option.is-active {
    color: #fff;
    background: linear-gradient(135deg, var(--pink-500), var(--pink-600));
    box-shadow: var(--shadow-pink);
}

@media (max-width: 600px) {
    .lang-switch__label { display: none; }
    .site-header__tools { gap: 10px; }
}