* {
    box-sizing: border-box;
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
}
body {
    background: linear-gradient(145deg, #f0f4f8 0%, #e6ecf3 100%);
    min-height: 100vh;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px;
}
.card {
    max-width: 700px;
    width: 100%;
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: 40px;
    box-shadow: 0 30px 50px rgba(0,20,30,0.2), 0 10px 20px rgba(0,0,0,0.1);
    padding: 28px 24px;
    border: 1px solid rgba(255,255,255,0.6);
}
h1 {
    font-size: 1.9rem;
    font-weight: 600;
    margin: 0 0 8px 0;
    color: #1a2e3b;
    display: flex;
    align-items: center;
    gap: 10px;
}
h1 small {
    font-size: 0.9rem;
    font-weight: 400;
    color: #3d5a6c;
    margin-left: auto;
}
.tabs {
    display: flex;
    gap: 12px;
    margin: 30px 0 25px 0;
    border-bottom: 2px solid #cbd6e3;
    padding-bottom: 8px;
}
.tab-btn {
    background: transparent;
    border: none;
    padding: 12px 28px;
    font-size: 1.25rem;
    font-weight: 600;
    border-radius: 48px;
    color: #3b5e7a;
    cursor: pointer;
    transition: 0.2s;
    letter-spacing: 0.3px;
    backdrop-filter: blur(4px);
}
.tab-btn.active {
    background: #ffffffd6;
    color: #0d2f41;
    box-shadow: 0 8px 16px -8px #1e3b4e40;
    border: 1px solid white;
}
.tab-content {
    display: none;
    opacity: 0;
    transform: translateY(5px);
    transition: 0.25s ease;
}
.tab-content.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
}
.input-group {
    margin-bottom: 24px;
    background: #f3f9ffc9;
    padding: 20px 24px;
    border-radius: 32px;
    backdrop-filter: blur(4px);
    border: 1px solid #ffffffba;
    box-shadow: inset 0 1px 4px #ffffff, 0 6px 12px #b5c9db4d;
}
.field-row {
    display: flex;
    flex-direction: column;
    margin-bottom: 20px;
}
.field-row label {
    font-weight: 600;
    color: #1c3c4f;
    margin-bottom: 8px;
    font-size: 1rem;
    display: flex;
    align-items: center;
    gap: 6px;
}
.field-row input, .field-row select {
    background: white;
    border: 2px solid #cbdae7;
    border-radius: 28px;
    padding: 14px 20px;
    font-size: 1.1rem;
    outline: none;
    transition: 0.2s;
    width: 100%;
}
.field-row input:focus, .field-row select:focus {
    border-color: #2f7e9e;
    box-shadow: 0 0 0 4px #a6c8e0;
}
.inline-row {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    align-items: flex-end;
}
.inline-row .field-row {
    flex: 1 1 150px;
}
.result-block {
    background: #1d3e4f;
    color: white;
    padding: 26px 28px;
    border-radius: 40px;
    margin-top: 28px;
    box-shadow: 0 20px 30px -10px #10262e;
    border: 1px solid #70b8d4;
}
.co2-value {
    font-size: 3.4rem;
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -1px;
    word-break: break-word;
}
.co2-unit {
    font-size: 1.3rem;
    font-weight: 400;
    opacity: 0.8;
    margin-left: 10px;
}
.detail-line {
    font-size: 1.2rem;
    margin-top: 12px;
    border-top: 2px dashed #5596b3;
    padding-top: 14px;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
}
.badge {
    background: #316277;
    border-radius: 60px;
    padding: 6px 18px;
    color: #dcf2ff;
}
.info-hint {
    background: #eaf0f9;
    border-radius: 28px;
    padding: 10px 20px;
    font-size: 0.95rem;
    color: #1a4356;
    margin: 12px 0 0;
}
hr {
    border: 1px solid #b9cfdf;
    margin: 24px 0 12px;
}
.footnote {
    text-align: right;
    color: #3f627c;
    font-weight: 500;
    margin-top: 12px;
}