:root {
    --bg: #f3f6fb;
    --surface: #ffffff;
    --text: #112132;
    --muted: #5e6d80;
    --line: #dbe4f0;
    --navy: #17395b;
    --blue: #315f93;
    --green: #1c7b55;
    --green-soft: #edf8f2;
    --shadow: 0 24px 50px rgba(17, 33, 50, 0.08);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: "Inter", "Segoe UI", Arial, sans-serif;
    color: var(--text);
    background:
        radial-gradient(circle at top left, rgba(49, 95, 147, 0.12), transparent 28%),
        radial-gradient(circle at bottom right, rgba(28, 123, 85, 0.12), transparent 30%),
        var(--bg);
}

.page-shell {
    max-width: 1180px;
    margin: 0 auto;
    padding: 40px 20px 80px;
}

.hero,
.section-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 28px;
    align-items: stretch;
}

.section-grid,
.content-band,
.footer-cta {
    margin-top: 32px;
}

.reverse {
    grid-template-columns: 0.95fr 1.05fr;
}

.hero-copy,
.hero-panel,
.calculator-card,
.band-card,
.architecture-card,
.footer-card {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 28px;
    box-shadow: var(--shadow);
}

.hero-copy {
    padding: 42px;
}

.hero-panel {
    padding: 22px;
    background: linear-gradient(145deg, #17395b 0%, #244d77 45%, #1c7b55 100%);
}

.hero-card {
    height: 100%;
    border-radius: 24px;
    padding: 28px;
    background: rgba(255, 255, 255, 0.12);
    color: #f7fbff;
    backdrop-filter: blur(8px);
}

.eyebrow,
.mini-label {
    margin: 0 0 12px;
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.eyebrow {
    color: var(--green);
}

.mini-label {
    color: rgba(255, 255, 255, 0.82);
}

h1,
h2,
h3,
p {
    margin-top: 0;
}

h1 {
    font-size: clamp(2.4rem, 4vw, 4.2rem);
    line-height: 1.02;
    letter-spacing: -0.04em;
    margin-bottom: 18px;
}

h2 {
    font-size: clamp(1.8rem, 2vw, 2.6rem);
    line-height: 1.08;
    letter-spacing: -0.03em;
    margin-bottom: 16px;
}

h3 {
    font-size: 1.08rem;
    margin-bottom: 10px;
}

.hero-text,
.section-copy p,
.hero-card p,
.footer-card p,
.bullet-card p,
.info-card p,
.architecture-card span,
.calculator-note {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--muted);
}

.hero-card p,
.hero-card strong,
.hero-card .mini-kicker,
.hero-card h2 {
    color: #f7fbff;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin: 24px 0 28px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 20px;
    border-radius: 999px;
    text-decoration: none;
    font-weight: 700;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
    transform: translateY(-1px);
}

.btn-primary {
    background: var(--navy);
    color: #fff;
    box-shadow: 0 12px 24px rgba(23, 57, 91, 0.18);
}

.btn-secondary {
    background: var(--green-soft);
    color: var(--green);
}

.hero-points {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 10px;
}

.hero-points li {
    position: relative;
    padding-left: 26px;
    color: var(--muted);
    font-weight: 500;
}

.hero-points li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 9px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--blue), var(--green));
}

.mini-grid {
    display: grid;
    gap: 16px;
    margin-top: 28px;
}

.mini-kicker {
    display: block;
    font-size: 0.72rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-bottom: 6px;
    opacity: 0.78;
}

.section-copy,
.calculator-card,
.architecture-card,
.band-card,
.footer-card {
    padding: 34px;
}

.info-stack,
.bullet-grid {
    display: grid;
    gap: 14px;
    margin-top: 22px;
}

.info-card,
.bullet-card {
    background: #fbfdff;
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 18px;
}

.bullet-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.calculator-header {
    margin-bottom: 20px;
}

.calculator-header .mini-label {
    color: var(--green);
}

.field-group {
    margin-bottom: 18px;
}

.field-group label,
.range-label strong {
    display: block;
    font-weight: 700;
    margin-bottom: 8px;
}

.range-label {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    align-items: baseline;
}

.field-shell {
    display: flex;
    align-items: center;
    gap: 10px;
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 0 14px;
    background: #fbfdff;
}

.field-shell span {
    color: var(--muted);
    font-weight: 700;
}

input[type="number"] {
    width: 100%;
    border: 0;
    outline: none;
    background: transparent;
    padding: 16px 0;
    font-size: 1rem;
    color: var(--text);
}

input[type="range"] {
    width: 100%;
    accent-color: var(--green);
}

.results-card {
    margin-top: 26px;
    padding: 22px;
    border-radius: 20px;
    background: linear-gradient(180deg, #17395b 0%, #20496f 100%);
    color: #fff;
}

.results-card .mini-label {
    color: rgba(255, 255, 255, 0.72);
}

.result-line {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 18px;
    padding: 14px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.result-line:last-child {
    border-bottom: 0;
}

.result-line span {
    color: rgba(255, 255, 255, 0.8);
}

.result-line strong {
    font-size: 1.24rem;
}

.result-line.emphasis strong {
    color: #8ff0bc;
}

.calculator-note {
    margin-top: 16px;
}

.content-band .band-card {
    padding: 38px 34px;
}

.timeline {
    list-style: none;
    padding: 0;
    margin: 24px 0 0;
    display: grid;
    gap: 18px;
}

.timeline li {
    position: relative;
    padding-left: 18px;
    color: var(--muted);
}

.timeline li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 8px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--green);
}

.timeline strong {
    display: block;
    margin-bottom: 6px;
    color: var(--text);
}

@media (max-width: 920px) {
    .hero,
    .section-grid,
    .reverse {
        grid-template-columns: 1fr;
    }

    .bullet-grid {
        grid-template-columns: 1fr;
    }

    .hero-copy,
    .section-copy,
    .calculator-card,
    .architecture-card,
    .band-card,
    .footer-card {
        padding: 24px;
    }
}