:root {
    color-scheme: light;
    --background: #eef3f7;
    --panel: #ffffff;
    --panel-soft: #f7fafc;
    --text: #17212b;
    --muted: #617181;
    --border: #d5dee7;
    --primary: #1769aa;
    --primary-dark: #0f4f84;
    --success: #176b45;
    --warning: #9a5c00;
    --danger: #a62b2b;
    --shadow: 0 10px 30px rgba(24, 42, 60, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-width: 320px;
    background:
        linear-gradient(180deg, #e8f1f7 0, var(--background) 300px);
    color: var(--text);
    font-family:
        Inter,
        system-ui,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;
    line-height: 1.5;
}

.site-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 2rem;
    padding: 2rem clamp(1rem, 4vw, 4rem);
    color: #ffffff;
    background:
        linear-gradient(135deg, #103f66, #1769aa 60%, #2386c8);
    box-shadow: var(--shadow);
}

.site-header h1 {
    margin: 0.15rem 0 0.35rem;
    font-size: clamp(1.9rem, 4vw, 3rem);
    line-height: 1.1;
}

.eyebrow {
    margin: 0;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.13em;
    text-transform: uppercase;
    opacity: 0.8;
}

.subtitle {
    max-width: 760px;
    margin: 0;
    color: rgba(255, 255, 255, 0.86);
}

.site-header nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
}

.site-header nav a {
    display: inline-flex;
    align-items: center;
    min-height: 40px;
    padding: 0.55rem 0.9rem;
    border: 1px solid rgba(255, 255, 255, 0.35);
    border-radius: 10px;
    color: #ffffff;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.1);
}

.site-header nav a:hover {
    background: rgba(255, 255, 255, 0.2);
}

.page-grid {
    display: grid;
    grid-template-columns: minmax(300px, 390px) minmax(0, 1fr);
    gap: 1.25rem;
    width: min(1600px, 100%);
    margin: 0 auto;
    padding: 1.25rem;
}

.results-column {
    display: grid;
    gap: 1.25rem;
    min-width: 0;
}

.panel {
    padding: 1.25rem;
    border: 1px solid var(--border);
    border-radius: 16px;
    background: var(--panel);
    box-shadow: var(--shadow);
}

.controls-panel {
    align-self: start;
    position: sticky;
    top: 1rem;
}

.panel h2 {
    margin: 0 0 1rem;
    font-size: 1.2rem;
}

fieldset {
    display: grid;
    gap: 0.85rem;
    margin: 0 0 1rem;
    padding: 1rem;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: var(--panel-soft);
}

legend {
    padding: 0 0.4rem;
    color: var(--primary-dark);
    font-weight: 700;
}

label {
    display: grid;
    gap: 0.35rem;
    color: #324252;
    font-size: 0.91rem;
    font-weight: 600;
}

input,
select,
button {
    width: 100%;
    min-height: 42px;
    border-radius: 9px;
    font: inherit;
}

input,
select {
    padding: 0.55rem 0.7rem;
    border: 1px solid #bcc9d5;
    color: var(--text);
    background: #ffffff;
}

input:focus,
select:focus {
    border-color: var(--primary);
    outline: 3px solid rgba(23, 105, 170, 0.14);
}

input:disabled,
select:disabled {
    cursor: not-allowed;
    color: #7c8995;
    background: #e8edf1;
}

.checkbox-label {
    grid-template-columns: auto 1fr;
    align-items: center;
}

.checkbox-label input {
    width: 19px;
    min-height: 19px;
    margin: 0;
}

.help-text {
    margin: -0.25rem 0 0.5rem;
    color: var(--muted);
    font-size: 0.84rem;
}

#manual-dimensions {
    display: grid;
    gap: 0.85rem;
}

button[type="submit"] {
    border: 0;
    padding: 0.7rem 1rem;
    color: #ffffff;
    font-weight: 700;
    cursor: pointer;
    background: var(--primary);
}

button[type="submit"]:hover {
    background: var(--primary-dark);
}

button[type="submit"]:disabled {
    cursor: wait;
    opacity: 0.65;
}

.status-message {
    min-height: 1.5rem;
    margin: 0.8rem 0 0;
    font-weight: 650;
}

.status-message.success {
    color: var(--success);
}

.status-message.error {
    color: var(--danger);
}

.status-message.loading {
    color: var(--primary-dark);
}

.results-grid {
    display: grid;
    grid-template-columns:
        repeat(auto-fit, minmax(180px, 1fr));
    gap: 0.75rem;
}

.result-card {
    min-width: 0;
    padding: 0.85rem;
    border: 1px solid var(--border);
    border-radius: 11px;
    background: var(--panel-soft);
}

.result-card .label {
    display: block;
    margin-bottom: 0.25rem;
    color: var(--muted);
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    text-transform: uppercase;
}

.result-card .value {
    display: block;
    overflow-wrap: anywhere;
    color: var(--text);
    font-size: 1.05rem;
    font-weight: 750;
}

.result-card.good {
    border-color: #a9d8c0;
    background: #f1fbf6;
}

.result-card.warning {
    border-color: #e7ca91;
    background: #fff9ed;
}

.chart-container {
    position: relative;
    height: 360px;
    margin-top: 1rem;
}

.note-panel {
    color: #3f4f5e;
    background: #f9fbfd;
}

.note-panel p {
    margin-bottom: 0;
}

@media (max-width: 1000px) {
    .site-header {
        flex-direction: column;
    }

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

    .controls-panel {
        position: static;
    }
}

@media (max-width: 600px) {
    .site-header {
        padding: 1.3rem 1rem;
    }

    .page-grid {
        padding: 0.75rem;
    }

    .panel {
        padding: 1rem;
        border-radius: 13px;
    }

    .chart-container {
        height: 300px;
    }
}