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

:root {
    --bg: #fafafa;
    --fg: #333;
    --border: #ddd;
    --input-bg: #fff;
    --status-bg: transparent;
    --status-error-bg: rgba(244, 67, 54, 0.1);
    --status-error-color: #d32f2f;
    --status-success-bg: rgba(76, 175, 80, 0.08);
    --status-success-color: #2e7d32;
}

[data-theme="dark"] {
    --bg: #1a1a1a;
    --fg: #e0e0e0;
    --border: #333;
    --input-bg: #2a2a2a;
    --status-bg: transparent;
    --status-error-bg: rgba(239, 83, 80, 0.15);
    --status-error-color: #ef5350;
    --status-success-bg: rgba(102, 187, 106, 0.06);
    --status-success-color: #81c784;
}

body {
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    background: var(--bg);
    color: var(--fg);
    height: 100vh;
    overflow: auto; /* allow scrolling when card is smaller than viewport */
    transition: background 0.3s, color 0.3s;
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    background: transparent;
    border: none;
    opacity: 0.4;
    transition: opacity 0.2s;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
}

.theme-toggle:hover {
    opacity: 1;
}

.container {
    display: grid;
    grid-template-columns: 1.4fr 1fr; /* give more space to left (session) */
    gap: 18px;
    height: auto; /* allow container to size to content inside the centered card */
    padding-bottom: 40px;
}

/* Centered framed card that limits layout width */
.app-card {
    max-width: 770px; /* reduced ~30% to make UI smaller */
    width: calc(100% - 48px);
    margin: 24px auto;
    background: var(--input-bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    box-shadow: 0 6px 18px rgba(10,10,10,0.06);
    padding: 12px;
}

.panel-left, .panel-right {
    padding: 16px;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.panel-left {
    border-right: 1px solid var(--border);
}

/* Panel Header with Status Bar */
.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
    height: 20px;
}

.panel-header label {
    margin-bottom: 0;
    font-size: 12px;
    font-weight: 600;
    color: var(--fg);
    text-transform: uppercase;
}

/* Unified label style used for session, secret, payload */
.field-label {
    margin-bottom: 0;
    font-size: 12px;
    font-weight: 600;
    color: var(--fg);
    text-transform: uppercase;
    letter-spacing: 0.02em;
}

.status-bar {
    font-size: 11px;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    background: var(--status-bg);
    padding: 2px 6px;
    border-radius: 3px;
    min-height: 16px;
    transition: all 0.3s;
}

.status-bar.error {
    background: var(--status-error-bg);
    color: var(--status-error-color);
}

.status-bar.success {
    background: var(--status-success-bg);
    color: var(--status-success-color);
}

/* Make status bars slightly smaller and align text */
.panel-header .status-bar {
    font-size: 11px;
    padding: 2px 8px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Input Elements */
textarea, input {
    width: 100%;
    padding: 12px;
    border: none;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    font-size: 12px;
    background: var(--input-bg);
    color: var(--fg);
    resize: none;
    transition: all 0.3s;
}

textarea:focus, input:focus {
    outline: none;
    border-color: var(--fg);
}

.section {
    margin-bottom: 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

#secret-input {
    height: 60px;
    margin-bottom: 20px;
}

#payload-input {
    height: 300px;
}

/* Make secret and payload inputs visibly boxed */
#secret-input, #payload-input {
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--input-bg);
}

.section:last-child {
    margin-bottom: 0;
}

/* Session Wrapper */
.session-wrapper {
    position: relative;
    border: 1px solid var(--border);
    background: var(--input-bg);
    display: grid;
    height: auto;
    max-height: 62vh; /* responsive cap so it doesn't grow too tall */
    overflow: auto;
}

#session-input {
    grid-area: 1 / 1;
    width: 100%;
    height: auto;
    max-height: 58vh;
    padding: 12px;
    font-size: 12px;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    background: transparent;
    color: transparent;
    caret-color: var(--fg);
    border: none;
    outline: none;
    resize: none;
    line-height: 1.8;
    word-break: break-all;
    white-space: pre-wrap;
    overflow: auto;
    z-index: 1;
}

#session-highlight {
    grid-area: 1 / 1;
    width: 100%;
    height: 100%;
    padding: 12px;
    font-size: 12px;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    pointer-events: none;
    overflow: hidden;
    white-space: pre-wrap;
    word-break: break-all;
    line-height: 1.8;
    color: var(--fg);
}

.token-payload {
    background: rgba(33, 150, 243, 0.12);
}

.token-signature {
    background: rgba(255, 152, 0, 0.12);
}

/* Responsive: stack on small screens */
@media (max-width: 900px) {
    .container {
        grid-template-columns: 1fr;
        gap: 12px;
    }
    .app-card {
        width: calc(100% - 24px);
        margin: 18px auto;
        padding: 12px;
    }
    .session-wrapper {
        max-height: 48vh;
    }
}

/* 底部版权信息 */
.footer {
    position: fixed;
    bottom: 15px;
    left: 0;
    right: 0;
    text-align: center;
    font-size: 12px;
    color: var(--fg);
    opacity: 0.6;
    font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
    z-index: 10;
    background: var(--bg);
    padding: 8px 0;
    margin: 0 20px;
    border-radius: 4px;
}

.footer a {
    color: inherit;
    text-decoration: none;
}

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