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

:root {
    --bg: #f5f5f7;
    --text-main: #111827;
    --text-muted: #6b7280;
    --accent-ml: #facc15;
    --accent-nlp: #0ea5e9;
    --accent-rl: #22c55e;
    --accent-ai: #a855f7;
    --card-bg: #ffffff;
    --card-border: rgba(148, 163, 184, 0.4);
    --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
    --shadow-lg: 0 18px 45px rgba(15, 23, 42, 0.12);
    --accent-danger: #dc2626;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: radial-gradient(circle at top, #ffffff 0, var(--bg) 55%);
    color: var(--text-main);
    line-height: 1.6;
    padding: 32px 20px 40px;
}

.container {
    max-width: 960px;
    margin: 0 auto;
}

header {
    margin-bottom: 40px;
    text-align: center;
}

h1 {
    font-size: 2.4rem;
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.05rem;
}

.deadline-list {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

/* CARD */

.deadline-card {
    position: relative;
    background: var(--card-bg);
    padding: 22px 22px 20px 26px;
    border-radius: 14px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--card-border);
    transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
    overflow: hidden;
}

/* subtle colored strip using ::before instead of a chunky border-left */
.deadline-card::before {
    content: "";
    position: absolute;
    inset-y: 0;
    left: 0;
    width: 3px;
    background: #e5e7eb;
}

.deadline-card.ml::before {
    background: var(--accent-ml);
}

.deadline-card.nlp::before {
    background: var(--accent-nlp);
}

.deadline-card.rl::before {
    background: var(--accent-rl);
}

.deadline-card.ai::before {
    background: var(--accent-ai);
}

.deadline-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-3px);
    border-color: rgba(148, 163, 184, 0.7);
}

.deadline-card.past {
    opacity: 0.55;
}

/* HEADER */

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 14px;
    gap: 10px 16px;
    flex-wrap: wrap;
}

.conference-info {
    min-width: 0;
}

.conference-name {
    font-size: 1.3rem;
    font-weight: 650;
    color: var(--text-main);
    text-decoration: none;
    display: inline-block;
    margin-bottom: 4px;
    letter-spacing: -0.02em;
}

.conference-name:hover {
    color: var(--accent-nlp);
}

.conference-meta {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* COUNTDOWN PILL */

.countdown {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--accent-danger);
    white-space: nowrap;
    padding: 4px 10px;
    border-radius: 999px;
    background: #fee2e2;
    border: 1px solid #fecaca;
}

.countdown.past {
    color: #6b7280;
    background: #e5e7eb;
    border-color: #d1d5db;
}

/* DETAILS GRID */

.deadline-details {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 10px 16px;
    margin-bottom: 6px;
    font-size: 0.9rem;
    align-items: center;
}

.detail-row {
    display: contents;
}

.detail-icon {
    width: 16px;
    height: 16px;
    color: var(--text-muted);
}

.detail-value {
    color: var(--text-main);
}

.detail-value a {
    color: var(--accent-nlp);
    text-decoration: none;
}

.detail-value a:hover {
    text-decoration: underline;
}

/* SECTION TITLE */

.section-title {
    font-size: 1.4rem;
    font-weight: 650;
    margin: 40px 0 18px 0;
    color: var(--text-main);
}

/* RESPONSIVE */

@media (max-width: 600px) {
    body {
        padding: 20px 14px 30px;
    }

    h1 {
        font-size: 2rem;
    }

    .deadline-card {
        padding: 18px 18px 16px 22px;
        border-radius: 12px;
    }

    .card-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .countdown {
        align-self: flex-start;
    }

    .deadline-details {
        grid-template-columns: auto 1fr;
        gap: 8px 12px;
    }
}