:root {
    --bg-color: #1c1917;
    --text-color: #e7e5e4;
    --accent-color: #d97706;
    --secondary-color: #a8a29e;
    --border-color: #44403c;
    --card-bg: #292524;
    --heading-color: #fafaf9;
    --shadow-color: rgba(0, 0, 0, 0.4);
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --radius: 12px;
}

[data-theme="light"] {
    --bg-color: #fafaf9;
    --text-color: #1c1917;
    --accent-color: #b45309;
    --secondary-color: #57534e;
    --border-color: #d6d3d1;
    --card-bg: #ffffff;
    --heading-color: #0c0a09;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-family);
    line-height: 1.6;
    padding: 1.5rem;
    max-width: 900px;
    margin: 0 auto;
    transition: background-color 0.3s ease, color 0.3s ease;
    -webkit-tap-highlight-color: transparent;
}

header {
    margin-bottom: 2.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

h1 {
    font-size: clamp(2rem, 5vw, 2.5rem);
    font-weight: 800;
    color: var(--heading-color);
    letter-spacing: -0.025em;
}

.creator {
    color: var(--secondary-color);
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

nav {
    display: flex;
    gap: 1rem;
    border-bottom: 1px solid var(--border-color);
    flex-wrap: wrap;
    padding-bottom: 1rem;
}

nav a {
    text-decoration: none;
    color: var(--secondary-color);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
}

nav a:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
}

nav a.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

nav a.active i {
    color: white !important;
}

nav a i {
    width: 18px;
    height: 18px;
}

.theme-toggle {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    padding: 0;
}

.sun-icon, .moon-icon {
    display: none !important;
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}
[data-theme="light"] .sun-icon { display: block !important; color: #f59e0b; }
[data-theme="dark"] .moon-icon { display: block !important; }
html:not([data-theme]) .moon-icon { display: block !important; }

section {
    margin-bottom: 3rem;
}

h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--heading-color);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Сетка карточек */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    border-radius: var(--radius);
    transition: var(--transition);
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.card:hover {
    transform: translateY(-4px);
    border-color: var(--accent-color);
    box-shadow: 0 12px 24px -8px var(--shadow-color);
}

.card h3 {
    margin-bottom: 0.75rem;
    color: var(--accent-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card p {
    color: var(--secondary-color);
    font-size: 0.95rem;
    flex-grow: 1;
}

.tool-section {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 2rem;
    border-radius: 16px;
}

.input-group { margin-bottom: 1.5rem; }
.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
    font-size: 0.9rem;
}

input[type="number"], textarea {
    width: 100%;
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 0.8rem 1rem;
    color: var(--text-color);
    font-family: inherit;
    font-size: 1rem;
    outline: none;
}

input:focus, textarea:focus { border-color: var(--accent-color); }

button {
    width: 100%;
    padding: 12px 24px;
    background: var(--accent-color);
    color: #fff;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    transition: var(--transition);
    font-family: inherit;
    font-size: 0.95rem;
}

button:hover {
    filter: brightness(1.1);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--shadow-color);
}

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

button:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    filter: grayscale(1);
}

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

.secondary-btn {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

.secondary-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
    background: var(--card-bg);
}

.danger-btn {
    background: #ef4444;
    color: white;
}

.danger-btn:hover {
    background: #dc2626;
}

.back-btn {
    width: auto;
    padding: 8px 16px;
    font-size: 0.85rem;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.back-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

/* Tool Header */
.tool-header {
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

/* Result Displays */
.result-display {
    margin-top: 2rem;
    padding: 2rem;
    background: var(--bg-color);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius);
    text-align: center;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--accent-color);
    min-height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    word-break: break-all;
    position: relative;
    transition: var(--transition);
}

.result-display:not(:empty) {
    border-style: solid;
    border-color: var(--accent-color);
    background: var(--card-bg);
    box-shadow: 0 8px 20px -10px var(--shadow-color);
}

.result-display.text-mode {
    font-size: 1rem;
    font-weight: 400;
    text-align: left;
    justify-content: flex-start;
    align-items: flex-start;
    min-height: 100px;
    padding: 1.5rem;
}

.result-details {
    margin-top: 1rem;
    text-align: center;
    color: var(--secondary-color);
    font-size: 0.95rem;
}

.advice {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 2rem;
    border-radius: 20px;
    margin: 1.5rem 0;
    font-size: 1.1rem;
    line-height: 1.6;
    text-align: center;
    box-shadow: 0 4px 15px var(--shadow-color);
    color: var(--text-color);
}

.advice b {
    color: var(--accent-color);
    display: block;
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

/* Forms & Inputs */
.options {
    margin-bottom: 1.5rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    font-size: 0.95rem;
    color: var(--secondary-color);
    margin: 1rem 0;
    user-select: none;
    transition: var(--transition);
}

.checkbox-label:hover {
    color: var(--text-color);
}

.checkbox-label input[type="checkbox"] {
    width: 20px;
    height: 20px;
    accent-color: var(--accent-color);
    cursor: pointer;
}

.input-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.button-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-top: 1.5rem;
}

.tool-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

@media (min-width: 768px) {
    body { padding: 3rem 2rem; }

    button { width: auto; }

    .input-row {
        grid-template-columns: 1fr 1fr;
        gap: 1.5rem;
    }

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

footer {
    margin-top: 5rem;
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
    color: var(--secondary-color);
    text-align: center;
}

.hidden { display: none !important; }