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

body {
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    min-height: 100vh;
    color: #eee;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    position: relative;
    text-align: center;
    padding: 48px 0 28px;
}

header h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}

header p {
    color: #aaa;
    font-size: 1.1rem;
}

.lang-switch {
    position: absolute;
    top: 8px;
    right: 0;
    display: inline-flex;
    border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: 999px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.06);
}

.lang-switch button {
    background: transparent;
    border: none;
    color: #bbb;
    padding: 8px 16px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.lang-switch button:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.08);
}

.lang-switch button.active {
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    color: #fff;
}

.tabs {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 12px 24px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    cursor: pointer;
    border-radius: 8px;
    transition: all 0.3s ease;
    font-size: 1rem;
}

.tab-btn:hover {
    background: rgba(255, 255, 255, 0.2);
}

.tab-btn.active {
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    border-color: transparent;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 30px;
    margin-bottom: 20px;
    backdrop-filter: blur(10px);
}

.card h2 {
    color: #00d4ff;
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #aaa;
    font-size: 0.95rem;
}

input[type="text"],
textarea {
    width: 100%;
    padding: 12px 16px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    color: #fff;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input[type="text"]:focus,
textarea:focus {
    outline: none;
    border-color: #00d4ff;
}

textarea {
    min-height: 100px;
    resize: vertical;
}

.btn {
    padding: 12px 28px;
    background: linear-gradient(90deg, #00d4ff, #7b2cbf);
    border: none;
    border-radius: 8px;
    color: #fff;
    font-size: 1rem;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, opacity 0.2s;
}

.btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 212, 255, 0.3);
}

.btn:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 25px rgba(255, 255, 255, 0.1);
}

.result-box {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(0, 212, 255, 0.3);
    border-radius: 12px;
    padding: 20px;
    margin-top: 20px;
    font-family: "Courier New", monospace;
}

.result-box h3 {
    color: #00d4ff;
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.key-display {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 10px 20px;
    font-size: 0.9rem;
}

.key-label {
    color: #7b2cbf;
    font-weight: bold;
}

.key-value {
    color: #fff;
    word-break: break-all;
}

.signature-display {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.sig-component {
    background: rgba(255, 255, 255, 0.05);
    padding: 15px;
    border-radius: 8px;
}

.sig-label {
    color: #aaa;
    font-size: 0.85rem;
    margin-bottom: 5px;
}

.sig-value {
    color: #fff;
    word-break: break-all;
}

.status {
    padding: 15px 20px;
    border-radius: 8px;
    margin-top: 15px;
    font-weight: bold;
}

.status.success {
    background: rgba(0, 255, 100, 0.2);
    border: 1px solid rgba(0, 255, 100, 0.5);
    color: #00ff64;
}

.status.error {
    background: rgba(255, 0, 0, 0.2);
    border: 1px solid rgba(255, 0, 0, 0.5);
    color: #ff4444;
}

.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.hidden {
    display: none !important;
}

.info-text {
    color: #888;
    font-size: 0.9rem;
    margin-bottom: 20px;
    line-height: 1.5;
}

.banner {
    background: rgba(123, 44, 191, 0.18);
    border: 1px solid rgba(123, 44, 191, 0.4);
    border-radius: 12px;
    padding: 14px 18px;
    margin-bottom: 20px;
    color: #d7c4f5;
    line-height: 1.5;
    font-size: 0.95rem;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.comparison-table th,
.comparison-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.comparison-table th {
    color: #00d4ff;
    font-weight: bold;
}

.comparison-table td {
    color: #ccc;
}

.pem-display {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(123, 44, 191, 0.3);
    border-radius: 8px;
    padding: 15px;
    font-family: "Courier New", monospace;
    font-size: 0.8rem;
    word-break: break-all;
    white-space: pre-wrap;
    color: #aaa;
    max-height: 220px;
    overflow-y: auto;
}

.input-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.site-footer {
    text-align: center;
    color: #777;
    font-size: 0.85rem;
    padding: 24px 0 12px;
}

@media (max-width: 768px) {
    .grid-2,
    .signature-display,
    .input-group {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 1.8rem;
        padding-top: 28px;
    }

    .lang-switch {
        position: static;
        margin: 0 auto 16px;
        display: flex;
        width: fit-content;
    }
}