:root {
    --bg: #f4f5f9;
    --card: #ffffff;
    --text: #1f2333;
    --text-muted: #6b7280;
    --border: #e5e7eb;
    --accent: #5b5bd6;
    --accent-hover: #4747c2;
    --accent-soft: #eef0fd;
    --danger: #e5533d;
    --danger-hover: #cf462f;
    --radius: 16px;
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }

body {
    font-family: 'Segoe UI', system-ui, -apple-system, Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 24px;
}

.container {
    background: var(--card);
    padding: 36px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    width: 100%;
    max-width: 440px;
}

h1, h2 {
    margin-top: 0;
    text-align: center;
    letter-spacing: -0.01em;
}

h2 {
    font-size: 1.4rem;
    font-weight: 700;
}

.subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: -8px;
    margin-bottom: 24px;
}

.breadcrumb {
    text-align: center;
    font-size: 0.85rem;
    margin-bottom: 20px;
}

.breadcrumb a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
}

.breadcrumb a:hover { text-decoration: underline; }

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

label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text);
}

input[type="text"], input[type="number"] {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 10px;
    box-sizing: border-box;
    font-size: 1rem;
    background: #fafafc;
    color: var(--text);
    transition: border-color 0.15s ease;
}

input[type="text"]:focus, input[type="number"]:focus {
    outline: none;
    border-color: var(--accent);
    background: #fff;
}

.checkbox-row {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.88rem;
}

.controls {
    display: flex;
    gap: 10px;
}

.btn {
    flex: 1;
    padding: 12px;
    font-size: 0.95rem;
    font-weight: 700;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.15s ease, transform 0.1s ease;
    color: #fff;
}

.btn:active { transform: scale(0.98); }

.btn-primary { background-color: var(--accent); }
.btn-primary:hover { background-color: var(--accent-hover); }

.btn-danger { background-color: var(--danger); }
.btn-danger:hover { background-color: var(--danger-hover); }

.btn-secondary {
    background-color: #eceef3;
    color: var(--text);
}
.btn-secondary:hover { background-color: #e2e4ec; }

.btn:disabled {
    background-color: #e5e7eb !important;
    color: #9ca3af !important;
    cursor: not-allowed;
}

.note {
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-top: 16px;
    text-align: center;
}

/* Homepage */
.home-hero {
    text-align: center;
    margin-bottom: 28px;
}

.home-hero h1 {
    font-size: 1.7rem;
    font-weight: 800;
    margin-bottom: 8px;
}

.home-hero p {
    color: var(--text-muted);
    font-size: 0.92rem;
    margin: 0;
}

.tool-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.tool-card {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 18px 20px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--card);
    text-decoration: none;
    color: inherit;
    transition: border-color 0.15s ease, box-shadow 0.15s ease, transform 0.15s ease;
}

.tool-card:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow);
    transform: translateY(-2px);
}

.tool-card .icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: var(--accent-soft);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    flex-shrink: 0;
}

.tool-card .info h3 {
    margin: 0 0 4px;
    font-size: 1.02rem;
}

.tool-card .info p {
    margin: 0;
    font-size: 0.84rem;
    color: var(--text-muted);
}