:root {
    --bg-dark: #0a0e17;
    --panel-bg: rgba(16, 22, 35, 0.9);
    --accent-it: #00d2ff;
    --accent-car: #ff3c00;
    --text-main: #e0e6ed;
    --text-muted: #8899a6;
    --shadow-it: 0 0 20px rgba(0, 210, 255, 0.3);
    --shadow-car: 0 0 20px rgba(255, 60, 0, 0.3);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Courier New', Courier, monospace;
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
    overflow-x: hidden;
    background-color: var(--bg-dark);
    background-image:
        url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="40" height="40" viewBox="0 0 40 40"><g fill-rule="evenodd"><g fill="%2300d2ff" fill-opacity="0.05"><path d="M0 0h40v40H0V0zm40 40h40v40H40V40z"/></g></g></svg>'),
        url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="80" height="80" viewBox="0 0 80 80"><g fill-rule="evenodd"><g fill="%23ff3c00" fill-opacity="0.05"><path d="M0 0h40v40H0V0zm40 40h40v40H40V40z"/></g></g></svg>');
    background-position: left top, right top;
    background-repeat: repeat-y, repeat-y;
    background-size: 50% auto, 50% auto;
    padding: 20px;
}

body::after {
    content: '';
    position: absolute;
    top: 0; left: 50%;
    width: 2px; height: 100%;
    background: linear-gradient(to bottom, var(--accent-it), var(--accent-car));
    z-index: 1;
    opacity: 0.3;
}

::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: rgba(0, 210, 255, 0.05); border-radius: 5px; }
::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--accent-it), var(--accent-car));
    border-radius: 5px;
    border: 2px solid var(--bg-dark);
}

.main-wrapper {
    width: 100%;
    max-width: 1100px;
    padding: 40px 20px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    position: relative;
    z-index: 10;
    align-self: center;
}

.converter-block {
    background: var(--panel-bg);
    border: 2px solid #222;
    border-radius: 20px;
    padding: 35px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.6);
    border-top: 4px solid var(--accent-it);
    border-bottom: 4px solid var(--accent-car);
    backdrop-filter: blur(10px);
}

.converter-block h3 {
    font-size: 1.6rem;
    margin-bottom: 25px;
    text-transform: uppercase;
    text-align: center;
    letter-spacing: 2px;
    background: linear-gradient(90deg, var(--accent-it), var(--accent-car));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.input-section {
    margin-bottom: 25px;
}

.converter-input {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid #444;
    padding: 20px;
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.8rem;
    border-radius: 12px;
    transition: var(--transition);
    resize: vertical;
}

.converter-input:focus {
    outline: none;
    border-color: var(--accent-it);
    box-shadow: var(--shadow-it);
}

.converter-input::placeholder {
    color: var(--text-muted);
}

.buttons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-bottom: 25px;
}

.converter-btn {
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid #444;
    color: var(--text-main);
    padding: 15px 20px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: 1px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.converter-btn i {
    font-size: 1.1rem;
}

.converter-btn:hover {
    transform: translateY(-2px);
    border-color: var(--accent-it);
    box-shadow: var(--shadow-it);
}

.converter-btn:active {
    transform: translateY(0);
}

.btn-upper:hover {
    background: rgba(0, 210, 255, 0.1);
    border-color: var(--accent-it);
}

.btn-lower:hover {
    background: rgba(255, 60, 0, 0.1);
    border-color: var(--accent-car);
}

.btn-title:hover {
    background: rgba(0, 255, 136, 0.1);
    border-color: #00ff88;
}

.btn-invert:hover {
    background: rgba(255, 204, 0, 0.1);
    border-color: #ffcc00;
}

.btn-sentence:hover {
    background: rgba(102, 126, 234, 0.1);
    border-color: #667eea;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 25px;
    margin-bottom: 12px;
    gap: 15px;
}

.result-header span {
    font-size: 1.1rem;
    color: var(--text-main);
    text-transform: uppercase;
    letter-spacing: 1px;
    border-left: 3px solid var(--accent-it);
    padding-left: 10px;
}

.clear-btn {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-muted);
    border: 1px solid #444;
    padding: 8px 20px;
    border-radius: 8px;
    font-size: 0.8rem;
    font-family: inherit;
    text-transform: uppercase;
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: 1px;
}

.clear-btn:hover {
    background: rgba(255, 60, 0, 0.1);
    color: #ff6b6b;
    border-color: var(--accent-car);
    box-shadow: 0 0 10px rgba(255, 60, 0, 0.2);
}

.result-box {
    background: rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    padding: 20px;
    font-family: 'Courier New', monospace;
    font-size: 1rem;
    line-height: 1.6;
    white-space: pre-wrap;
    color: #ccc;
    min-height: 100px;
    max-height: 400px;
    overflow-y: auto;
    border-left: 3px solid var(--accent-it);
    word-break: break-word;
}

.copy-btn {
    background: linear-gradient(135deg, var(--accent-it) 0%, var(--accent-car) 100%);
    color: white;
    border: none;
    padding: 10px 25px;
    border-radius: 8px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: 1px;
    margin-top: 15px;
}

.copy-btn:hover {
    transform: scale(1.03);
    box-shadow: var(--shadow-car);
}

.info-block {
    margin-top: 40px;
    background: rgba(10, 14, 23, 0.6);
    border: 1px dashed #333;
    border-radius: 14px;
    padding: 25px;
    transition: var(--transition);
}

.info-block h4 {
    font-size: 1.1rem;
    color: var(--accent-it);
    text-transform: uppercase;
    margin-bottom: 15px;
    letter-spacing: 1px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.info-block p {
    font-size: 0.95rem;
    line-height: 1.6;
    color: var(--text-muted);
    margin-bottom: 15px;
}

.info-features {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.info-features li {
    font-size: 0.9rem;
    color: var(--text-main);
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.info-features li::before {
    content: '»';
    color: var(--accent-car);
    font-weight: bold;
}

footer {
    text-align: center;
    margin-top: 20px;
    color: var(--text-muted);
    font-size: 0.85rem;
    align-self: center;
}

.back-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.back-link:hover {
    color: var(--accent-it);
}

@media (max-width: 600px) {
    .buttons-grid { grid-template-columns: 1fr; }
    .result-header { flex-direction: column; align-items: flex-start; }
    .clear-btn { width: 100%; padding: 12px; text-align: center; }
    .copy-btn { width: 100%; }
    body::after { display: none; }
}