:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --secondary: #ec4899;
    --success: #10b981;
    --radius: 16px;

    /* Default Dark Theme */
    --bg: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --border: rgba(148, 163, 184, 0.1);
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --input-bg: rgba(15, 23, 42, 0.6);
    --input-focus-bg: rgba(15, 23, 42, 0.8);
    --card-hover-bg: rgba(30, 41, 59, 0.6);
    --table-header-bg: rgba(15, 23, 42, 0.5);
    --table-row-hover: rgba(255, 255, 255, 0.02);
    --bg-grad-1: rgba(99, 102, 241, 0.15);
    --bg-grad-2: rgba(236, 72, 153, 0.1);
    --common-bg: rgba(15, 23, 42, 0.5);
    --card-inner-bg: rgba(15, 23, 42, 0.4);
    --input-text: #ffffff;
    --card-value-text: #ffffff;
    --plot-grid: rgba(255, 255, 255, 0.05);
}

@media (prefers-color-scheme: light) {
    :root:not([data-theme='dark']) {
        --bg: #f8fafc;
        --card-bg: rgba(255, 255, 255, 0.8);
        --text: #0f172a;
        --text-muted: #475569;
        --border: rgba(0, 0, 0, 0.05);
        --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
        --glass-bg: rgba(255, 255, 255, 0.7);
        --glass-border: rgba(0, 0, 0, 0.1);
        --input-bg: rgba(255, 255, 255, 0.8);
        --input-focus-bg: rgba(255, 255, 255, 1);
        --card-hover-bg: rgba(255, 255, 255, 0.9);
        --table-header-bg: rgba(241, 245, 249, 0.8);
        --table-row-hover: rgba(0, 0, 0, 0.02);
        --bg-grad-1: rgba(99, 102, 241, 0.07);
        --bg-grad-2: rgba(236, 72, 153, 0.05);
        --common-bg: rgba(241, 245, 249, 0.5);
        --card-inner-bg: rgba(241, 245, 249, 0.4);
        --input-text: #0f172a;
        --card-value-text: #0f172a;
        --plot-grid: rgba(0, 0, 0, 0.05);
    }
}

[data-theme='light'] {
    --bg: #f8fafc;
    --card-bg: rgba(255, 255, 255, 0.8);
    --text: #0f172a;
    --text-muted: #475569;
    --border: rgba(0, 0, 0, 0.05);
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.1);
    --input-bg: rgba(255, 255, 255, 0.8);
    --input-focus-bg: rgba(255, 255, 255, 1);
    --card-hover-bg: rgba(255, 255, 255, 0.9);
    --table-header-bg: rgba(241, 245, 249, 0.8);
    --table-row-hover: rgba(0, 0, 0, 0.02);
    --bg-grad-1: rgba(99, 102, 241, 0.07);
    --bg-grad-2: rgba(236, 72, 153, 0.05);
    --common-bg: rgba(241, 245, 249, 0.5);
    --card-inner-bg: rgba(241, 245, 249, 0.4);
    --input-text: #0f172a;
    --card-value-text: #0f172a;
    --plot-grid: rgba(0, 0, 0, 0.05);
}

[data-theme='dark'] {
    --bg: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --border: rgba(148, 163, 184, 0.1);
    --shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --input-bg: rgba(15, 23, 42, 0.6);
    --input-focus-bg: rgba(15, 23, 42, 0.8);
    --card-hover-bg: rgba(30, 41, 59, 0.6);
    --table-header-bg: rgba(15, 23, 42, 0.5);
    --table-row-hover: rgba(255, 255, 255, 0.02);
    --bg-grad-1: rgba(99, 102, 241, 0.15);
    --bg-grad-2: rgba(236, 72, 153, 0.1);
    --common-bg: rgba(15, 23, 42, 0.5);
    --card-inner-bg: rgba(15, 23, 42, 0.4);
    --input-text: #ffffff;
    --card-value-text: #ffffff;
    --plot-grid: rgba(255, 255, 255, 0.05);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg);
    background-image:
        radial-gradient(at 0% 0%, var(--bg-grad-1) 0px, transparent 50%),
        radial-gradient(at 100% 0%, var(--bg-grad-2) 0px, transparent 50%);
    color: var(--text);
    margin: 0;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background: transparent;
    padding: 4rem 1rem 6rem;
    text-align: center;
}

header h1 {
    margin: 0;
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.05em;
    background: linear-gradient(to right, #818cf8, #f472b6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 0 10px rgba(129, 140, 248, 0.3));
}

header p {
    margin-top: 1rem;
    color: var(--text-muted);
    font-size: 1.2rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

main {
    max-width: 1100px;
    margin: -4rem auto 4rem;
    padding: 0 1.5rem;
    width: 100%;
    box-sizing: border-box;
}

section {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: var(--radius);
    padding: 2.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 3rem;
    border: 1px solid var(--glass-border);
}

.common-block {
    background: var(--common-bg);
    padding: 2rem;
    border-radius: var(--radius);
    margin-bottom: 2rem;
    border: 1px solid var(--glass-border);
}

.scenario-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #818cf8;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.scenario-title::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 1.25rem;
    background: currentColor;
    border-radius: 2px;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

label {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-muted);
}

input {
    background: var(--input-bg);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    padding: 0.85rem 1rem;
    color: var(--input-text);
    font-size: 1rem;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

input:focus {
    outline: none;
    border-color: var(--primary);
    background: var(--input-focus-bg);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.2);
    transform: scale(1.01);
}

button {
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    color: white;
    padding: 1rem 2rem;
    border: none;
    border-radius: 12px;
    font-weight: 700;
    font-size: 1.1rem;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(99, 102, 241, 0.5);
    filter: brightness(1.1);
}

button:active {
    transform: translateY(0);
}

.dual-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2.5rem;
}

@media (max-width: 600px) {
    .dual-grid {
        grid-template-columns: 1fr;
    }
}

.summary-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
}

.card {
    background: var(--card-inner-bg);
    padding: 1rem;
    border-radius: 14px;
    border: 1px solid var(--glass-border);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    /* height: 100%; removed to avoid stretching */
}

.card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
    background: var(--card-hover-bg);
}

.card .label {
    display: block;
    color: var(--text-muted);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.4rem;
    line-height: 1.2;
    min-height: 1.8rem;
    /* Adjusted for tighter 2 lines */
}

.card .value {
    display: block;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--card-value-text);
}

.result h2 {
    font-size: 2rem;
    font-weight: 800;
    margin-top: 0;
    margin-bottom: 2.5rem;
    text-align: center;
}

.table-container {
    overflow-x: auto;
    background: var(--card-inner-bg);
    border-radius: 12px;
    border: 1px solid var(--glass-border);
}

table {
    width: 100%;
    border-collapse: collapse;
}

th {
    background: var(--table-header-bg);
    padding: 1rem;
    text-align: left;
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--glass-border);
    font-size: 0.9rem;
}

tr:hover td {
    background: var(--table-row-hover);
}

.error-msg {
    color: #ef4444;
    background: var(--card-inner-bg);
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 2rem;
    border: 1px solid rgba(239, 68, 68, 0.2);
    text-align: center;
    font-weight: 600;
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

footer {
    padding: 4rem 2rem;
    text-align: center;
    color: var(--text-muted);
    font-weight: 500;
}

.theme-toggle {
    position: fixed;
    top: 1.5rem;
    right: 1.5rem;
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 1000;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: var(--shadow);
    color: var(--text);
    font-size: 1.25rem;
}

.theme-toggle:hover {
    transform: scale(1.1) rotate(15deg);
    border-color: var(--primary);
    background: var(--card-hover-bg);
}

.theme-toggle .sun {
    display: none;
}

.theme-toggle .moon {
    display: block;
}

[data-theme='light'] .theme-toggle .sun {
    display: block;
}

[data-theme='light'] .theme-toggle .moon {
    display: none;
}

@media (prefers-color-scheme: light) {
    :root:not([data-theme='dark']) .theme-toggle .sun {
        display: block;
    }

    :root:not([data-theme='dark']) .theme-toggle .moon {
        display: none;
    }
}

[data-theme='dark'] .theme-toggle .sun {
    display: none;
}

[data-theme='dark'] .theme-toggle .moon {
    display: block;
}

@media (max-width: 600px) {
    .theme-toggle {
        top: 1rem;
        right: 1rem;
        width: 38px;
        height: 38px;
        font-size: 1.1rem;
    }
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}

.modal-content {
    background-color: var(--bg);
    margin: 10% auto;
    padding: 2.5rem;
    border: 1px solid var(--glass-border);
    width: 90%;
    max-width: 600px;
    border-radius: var(--radius);
    position: relative;
    color: var(--text);
    line-height: 1.6;
    box-shadow: var(--shadow);
}

.close-button {
    position: absolute;
    right: 1.5rem;
    top: 1rem;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: color 0.2s;
}

.close-button:hover {
    color: var(--text);
}

#help-trigger {
    cursor: pointer;
    opacity: 0.7;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    vertical-align: middle;
    color: var(--text-muted);
}

#help-trigger:hover {
    opacity: 1;
    color: var(--primary);
    transform: scale(1.1);
}